Dental News December 2008

Volume XV, Number IV, 2008 EDITORIAL TEAM Alfred Naaman, Nada Naaman, Jihad Fakhoury, Dona Raad, Antoine Saadé, Lina Chamseddine, Tarek Kotob, Mohammed Rifai, Bilal Koleilat, Mohammad H. Al-Jammaz COORDINATOR Eliane Jkayem ART DEPARTMENT Krystel Kouyoumdjis SUBSCRIPTION Micheline Assaf, Nariman Nehmeh ADVERTISING Josiane Younes PHOTOGRAPHY Albert Saykali TRANSLATION Gisèle Wakim, Marielle Khoury DIRECTOR Tony Dib ISSN 1026-261X

CONTENTS CONTENTS CONTENTS CONTENTS

13

Ultraviolet-induced fluorescence: shedding new light on dental biofilms and dental caries Prof. Laurence J. Walsh and Dr. Fardad Shakibaie

22

Blending Reciprocation with the Creation of Larger Apical Diameters Dr. Richard E. Mounce

27

Micro-tensile bond strength of one-step adhesives to dentin Dr. Khalid M. Abdelaziz, Dr. Neveen M. Ayad

40

Beirut International Dental Meeting 2008

52 54

Biomet 3i symposium

64

16th Alexandria Dental Congress

74

Product Review

DENTAL NEWS – Sami Solh Ave., G. Younis Bldg.

POB: 116-5515 Beirut, Lebanon.

Tel: 961-3-30 30 48 Fax: 961-1-38 46 57 Email: info@dentalnews.com Website: www.dentalnews.com

INTERNATIONAL REVIEW BOARD Pr. M.A. Bassiouny BDS, DMD, MSc, Ph.D. Director International Program, Temple University, Philadelphia, USA. Pr. N.F. Bissada D.D.S., M.S.D Professor and Chairman, Department of Periodontics, Case Western Reserve University, USA. Pr. Jean-Louis Brouillet D.C.D, D.S.O. Chairman, Department of Restorative Dentistry, AixMarseille II, France.

Pierre Colon D.C.D., D.S.O. Maître de conférence des universités, Paris, France.

Dr. Jean-Claude Franquin, Directeur de l’Unité de Recherche ER116, Marseille, France.

Pr. Gilles Koubi D.C.D., D.S.O. Department of Restorative Dentistry, Aix-Marseille II, France.

Pr. Guido Goracci. University LA SAPIENZA, School of Medicine & Dentistry, Roma, Italia.

Dr. Olivier Hue, Faculté de chirurgie dentaire de Paris VII, rue Garancière, Paris, France.

Brian J. Millar BDS, FDSRCS, Ph.D. Guy’s, King’s, and St. Thomas’ College School of Medecine & Dentistry, London, UK. Pr. Dr. Klaus Ott, Director of the Clinics of Westfälischen Wilhelms-University, Münster, Germany.

Wilhelm-Joseph Pertot DEA, Maître de conférence, Aix-Marseille II, France.

Pr. James L. Gutmann, Professor and Director, Graduate Endodontics, Baylor College of Dentistry, Dallas, Texas, USA. Pr. Dr. Alfred Renk, Bayerische Julius-Maximilians-University, Würzburg, Germany.

Dr. Philippe Roche-Poggi DEA. Maître de conférence des universités, Aix-Marseille II, France.

Michel Sixou D.C.D., D.E.A. Department of Priodontology, Toulouse, France.

Pr. M. Sharawy B.D.S., Ph.D. Professor and Director, Department of Oral biology, Medical College of Georgia, Augusta, Georgia, USA.

DENTAL NEWS IS A QUARTERLY MAGAZINE DISTRIBUTED MAINLY IN THE MIDDLE EAST & NORTH AFRICA IN COLLABORATION WITH

3rd CAD/CAM & computerized Dentistry 2008

THE COUNCIL OF DENTAL SOCIETIES FOR THE GCC. Statements and opinions expressed in the articles and communications herein are those of the author(s) and not necessarily those of the Editor(s) or publisher. No part of this magazine may be reproduced in any form, either electronic or mechanical, without the express written permission of the publisher.

3

TEBODONT

®

Melaleuca alternifolia (tea tree oil) • antimicrobial • fungicidal • antiviral • antiseptic

• a herbal alternative in gum problems • no discoloration of the teeth • no change of the sense of taste Dr. Wild Dental research, CH-4132 Muttenz/Switzerland, www.wild-pharma.com Dr. Wild’s Mideast Regional Office: Actco, P.O. Box 40746, Larnaca 6306, Cyprus.

Tel.: (24) 623515 / 654252, Fax: (24) 623844. E-mail: joeissa@yahoo.com

Sensitive toothnecks, inflamed gums, prevention of caries • desensitizes • remineralizes • antiplaque • caries prophylaxis

intensive treatment

Bahrain: Awal Pharmacy, East Riffa, Bahrain. Egypt: Sesic, Alexandria. Jordan: Nairoukh Drugstore, Amman. Kuwait: Al-Maseela Pharmaceutical Co., Safat. Lebanon: A.M.G. Medical.Jdeideh-Azur Center Oman: Ibn Sina Pharmacy L.L.C., Muscat. Qatar: Ahmed Khalil Al Baker & Sons, Doha. Saudi Arabia: Depot Pharmaceutique du Moyen Orient, Jeddah. Sudan: Pharma Care Co, Khartoum. United Arab Emirates: Al Hayat Pharmaceuticals, Sharjah. Yemen: Al Rawdha Trading Group, Sana’a.

3M Unitek Symposium in Dubai: The future of intelligent orthodontics 3M Unitek, the world-leading manufacturer of orthodontic systems, sets the course for the future during a symposium in Dubai from the 6th to the 7th of March 2009. In an oriental setting, world-leading contributors will guide the participants through current orthodontic topics with lectures and hands-on workshops, presenting groundbreaking technologies that meet both cosmetic and medical requirements. Subsequently, the participants will have the opportunity to attend a two-day certification training for the lingual bracket system Incognito™. The symposium is complemented by an exclusive social programme, with optional excursion offering insights into the fabulous world of the Arabian Nights.

World-leading experts as contributors The symposium offers the participants a holistic overview over the current seminal topics in orthodontics. 3M Unitek e.g. managed to invite a top class panel of world-leading experts as contributors.

Renowned key-note speakers, like Dr. Bjorn Zachrisson and Dr. Sverker Toreskog provide an interdisciplinary overview of the replacement of incisors in the maxilla. Dr. Lars Christensen explains the differences between conventional orthodontics and the use of self-reg-

á````````````````````````````ë°üdG IQGRh á``````````````````jÉYQ â```````–

…Oƒ©°ùdG á«ë°üdG ájÉYôdG ¢Vô```©```e ádó«°üdGh ¿Éæ°SC’G áHÉÑWh ø`«`eCÉ`à`dGh Ö`£`∏d ô°û``Y ¢SOÉ°ùdG ‹hó``dG ió`à`æ`ª`dGh ¢Vô`©`ª`dG äGÈàıG äGõ«¡Œh ᫪∏©dG äGó©ŸGh

ulating brackets with the help of clinical studies. Dr. Anoop Sondhi addresses self-regulating brackets with regards to efficiency and productivity aspects in daily clinical business and will also give a lecture on the SmartClipTM system. On the next day, Dr. Jason Cope provides an overview over the placement of mini-screw implants and expert Dr. Dirk Wiechmann reports on the treatment success with the Incognito lingual bracket system. Workshops offer the participants to test the proper use of the SmartClip™ system.

An Incognito™ certification training directed by Dr. Wiechmann is offered on two additional days. The participation in this training is a prerequisite for the practical use of Incognito. In this system, the brackets and arches are manufactured individually and attached to the inner side of the teeth. Being completely invisible, it takes only a short familiarisation period until Incognito is no longer perceived by the patient. Thus, orthodontic treatment is also an option for patients, who have previously rejected this for cosmetic reasons.

For more information and registration forms, please visit www.3MUnitekdubai09.com.

Under the esteemed patronage of the Saudi Ministry of Health

Saudi Healthcare Saudi Arabia’s 16th International Exhibition & Symposium for Medical, Insurance, Dental, Pharmaceuticals, Scientific Equipment & Labware

And

…Oƒ©°ùdG äÉ«Ø°ûà°ùŸG ¢Vô```©```e äÉ«Ø°ûà°ù`ª∏d á«Ñ`£dG ô`«`Z äGõ`«¡éà`dGh äGOGóeE’Gh á«àëàdG á«æÑ∏d ¢SOÉ°ùdG ‹hódG çó◊G

™e øeGõàdÉH

Saudi Hospital Saudi Arabia’s 6th International Event for Non-Medical Hospital Infrastructure, Supplies and Furnishings

Held concurrently

á«fóÑdG ábÉ«∏dGh áëüdG ¢Vô©e á«fóÑdG ábÉ«∏dGh áë°üdÉH ájÉæ©dG äÉeóNh äGó©eh ¢Vhô©d ÊÉãdG ‹hódG çó◊G

`g 1430 ¤hC’G iOɪL 19 - 16 äÉ«dÉ©ØdGh äÉjóàæª∏d Ió`L õcôe ájOƒ©°ùdG á«Hô©dG áμ∏ªŸG - IóL

6

11 - 14 May 2009 Jeddah Centre for Forums & Events Owned by J.C.C.I

IóL á¶aÉëà á«YÉæ°üdG ájQÉéàdG áaô¨∏d ™HÉàdG

á```````≤£æŸG ‘ Rô``HC’G ‹hó``dG ≈``≤à∏ŸGh á```μ∏ªŸG iƒ``à°ùe ≈``∏Y »``°ù«FôdG çó``◊G -

Saudi Arabia’s 2nd International Event of Products, Equipment and Services for Health, Fitness & Wellness

SHASH

Jeddah, Kingdom of Saudi Arabia

SHASH - The Kingdom’s National Showcase and the Region’s International Forum

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

December 17 - 18, 2008 The 15th Oman Dental Conference, Grand Hyatt Muscat, Sultanate of Oman Email: odc2008@oman-dental.org Website: www.oman-dental.org March 10 - 12, 2009 AEEDC Dubai, Dubai International Convention & Exhibition Center Email: index@emirates.net.ae Website: http://aeedc.com

March 24 - 28, 2009 The IDS 2009, Cologne.

Website: http://www.ids-cologne.de April 20 – 22, 2009 20th Saudi Dental Society and 2nd National Guard International Conference. To be held at the King Fahad cultural center, Riyadh.

Email: info@sdsam.org Website: http://www.sdsam.org

ADVERTISING INDEX 3M ESPE 7 - ACTEON 9 - A-DEC 73 - AMANN GIRRBACH 55 - BELMONT 67 - BEYOND 51 - BIEN AIR 69 - BIOMET 3i 53 - BLUE X 8 - CASTELLINI 26 - CAVEX 75 COLTENE WHALEDENT 49 - DISCUS DENTAL 30 - DURR 16 - EMOFORM 4, 5 - GC 10 - GSK C1, 79 - HU - FRIEDY 19 - INIBSA 43 - INTENSIV 25 - INVISALIGN 78 - IVOCLAR VIVADENT C4, 1 - KAVO C3 - KAVO - GENDEX 57 - KERR 20, 59 - KETTENBACH 35 - KOMET 31 - LEONE 38 - MECTRON 45 - METASYS 71 - MICRO MEGA 42 MOCOM 56 - MORITA 29 - NSK 80 - S DENTI 21 - SHOFU 33 - SIRONA 15 - SOREDEX 39 - SVENSKA 63 - SYBRON ENDO 23 - VITA 47 - VOCO 28 - W&H 61 ZHERMACK 2 - ZIMMER 77

www.dentalnews.com www.dentalnews.com T e l : 9 6 1 - 3 - 3 0 3 0 4 8 F a x : 9 6 1 - 1 - 3 8 4 6 5 7 Email: info@dentalnews.com

GET YOUR ISSUE ONLINE DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Volume XV, Number IV, 2008 11 11

Distinguish yourself

Blended learning: An ideal combination for general dental practice ing's College London Dental Institute is the largest Dental Institute in Europe with its wide range of teaching programmes. Most popular of the postgraduate programmes are the blended learning degrees. Blended learning is described as 'a learning solution that incorporates a mix of online and face-to-face elements'. Busy practitioners can choose their time and place to study the academic components of the courses online and focus on the face-to-face intensive courses for the hands-on learning experience.

These residential components are available annually in the UK and India.

K

The MSc Advanced General Dental Practice (AGDP) is aimed at dental practitioners who wish to develop their clinical skills and expand on BDS level knowledge. It covers a range of topics from clinical skills to practice management to enable dentists to run a successful and rewarding dental practice.

The MClinDent in Fixed and Removable Prosthodontics (FRP) is our most popular programme and covers more advanced skills. It is recognised worldwide as an additional postgraduate degree. It begins alongside the AGDP programme but goes on to train dentists in managing advanced clinical problems such as severe tooth wear, TMJ dysfunction, aesthetic challenges, endodontics and implant restoration.

Similar programmes are currently available in Dental Public Health (DPH) and Dental and Maxillofacial Radiology (DMFR). In the coming year we are launching MSc's in Aesthetic Dentistry, Removable Prosthetics, Maxillofacial Prostheses and Dental Implantology.

The mode of delivery for all our blended programmes, has been designed to enable dentists from all around the world to remain in dental practice while training, allowing them to maintain clinical contact and establish a dental practice using skills learnt on the programme. The residential courses of approximately 9 days duration, held at one of our training centres, will provide the supporting faceto-face tuition in clinical skills. The training centres are in London and India, both providing the same programme taught by King's staff and

lead to the same King's MSc degree. Examinations are held in the student's home country with one written paper per module.

The success of the programmes comes from the balance between interactive online content, which includes ready access to the King's College London e-library, and the intensive annual 9 day block faceto-face teaching courses which provide the hands-on elements essential to a dental programme. Master's courses also include one-to-one tutoring for the final year of study.

The MSc programme runs over 3 years (4 years for MClinDent FRP) through part-time training. For any dentist not wishing to sign up for the full MSc (180 European credits) or MClinDent (360 European credits) then it is possible to attend for a shorter course leading to a Certificate (60 credits) or Diploma (120 credits).

The closing date for applications was 31 August 2008 for entry in January 2009; however late applications are being considered while places remain on the January 2009 UK intake and the February 2009 intake on the India residential programme. Applications can be made for 2010.

All courses are quality assured, independently verified and are taught by experts from the King's College London Dental Institute and other centres of excellence around the UK. Scholarships are available and further information about the course is available on our website (below), from where an application form can also be downloaded.

For further information please see: www.kcl.ac.uk/distancedentistry or email distancedentistry@kcl.ac.uk

Dr Brian Millar BDS, FDSRCS, PhD Director of Distance Learning, Senior Lecturer in Primary Dental Care, Consultant in Restorative Dentistry.

Specialist in Prosthodontics

Ultraviolet-induced fluorescence: shedding new light on dental biofilms and dental caries <By Prof. Dr. Laurence J. Walsh* and Fardad Shakibaie** he ultraviolet (UV) spectrum is traditionally divided into three UV bands: UVA (315-400 nm, also termed black light, long wave or near UV), UVB (280-315 nm, also termed middle UV - responsible for the sunburn response), and UVC (200-280 nm, also termed short wave UV)1. Having the lowest photon energy of the three ultraviolet wavebands, UVA has little effect on microbial pathogens and virtually no effect on human tissue with short-term exposures.

T

UVA is the important band in terms of diagnostic applications in dentistry.

The ability of UVA to make biological materials fluoresce is well known in medicine and dentistry as well as in industry. For example, UVA sources have application for identifying materials such as dyes, inks, minerals, chemical and various biological materials (such as blood, when used in forensic science). Light in the visible violet and UVA wave bands can also initiate chemical reactions which contribute to the photopolymerization of some dental composite materials, as well as adhesives, coatings, and resins used in fields other than dentistry.

A primer on fluorescence The process of fluorescence is of particular interest for diagnostic applications in dentistry as well as for other areas of health care.

Upon absorbing UVA light, certain molecules (fluorophores) become electronically excited to high energy levels, and then decay to lower energy levels by emitting radiation (emission or luminescence).

Fluorescence occurs if the transition is between states of the same electron spin and phosphorescence if the transition occurs between states of different spin. At low concentrations, the emission intensity is linearly proportional to the concentration of the molecule present in the target tissue. Because of this feature, molecular fluorescence is very useful for quantification.

Luminescence is a general term used to describe the emission of radiation, which incorporates both fluorescence (short lived) and phosphorescence (long lived), as well as other phenomena such as bioluminescence.

Many naturally occurring substances fluoresce, including minerals, fungi, bacteria, keratin, collagens and other components of body tissue; this is termed primary fluorescence or autofluorescence.

Molecular fluorescence emissions persists only as long as the stimulating radiation is continued, unlike the process of phosphorescence, which persists as an afterglow after the incoming exciting light has been turned off. If light emission occurs within one millionth of a second of light exposure, the luminescence is fluorescence, whereas if light emission takes longer than this, the luminescence is phosphorescence.

In molecular fluorescence, the colour of the emitted light has a longer wavelength than the colour of the exciting light. For example, when a molecule absorbs UVA light, the emissions are often in the visible spectrum. This relationship is known as Stokes' law, named after

Figure 1: UVA light induces PP9 red fluorescence which can then be imaged for diagnostic purposes *Technology editor of Australasian Dental Practice magazine.

He is also a noted commentator on and user of new technologies and is the Head of The University of Queensland School of Dentistry. **Dr Shakibaie is a PhD student in the UQ School of Dentistry working in the field of biophotonics. A dental graduate of the University of Queensland, he completed his MPhil in 2006 working on laser-induced fluorescence for diagnostic applications DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

ULTRAVIOLET-INDUCED FLUORESCENCE

13

Sir George Stokes, who published the first significant paper on fluorescence in 1852.

Fluorophores are excited by a range of wavelengths, and also emit over a broad range. Thus, for any fluorophore there will be some overlap between its absorption (excitation) spectrum and its emission spectrum. The difference between the absorption maximum and the emission maximum is known as the Stokes' shift.

Light sources used for fluorescence must produce light within the absorption region of the fluorophore of interest, at sufficient intensity.

Until recently, the types of UVA light sources used included nitrogen lasers, helium cadmium lasers, high pressure mercury lamps, high pressure xenon lamps, and metal-halide arc lamps. These light sources are large, expensive, and have limited lifespans. With advances in LED technology, UVA emitting LEDs have now been developed.

Common UVA wavelengths in commercially available LEDs are: 375, 385, 395 and 405 nm. UVA LEDs are small, long lasting and very reliable, by comparison with other light sources. Examples of dual wavelength dental curing lights with visible blue LEDs and UVA LEDs are the Ultradent UltraLume 5™ and the GC GLight ™. UVA LEDs have also been incorporated into dental imaging systems and examples of this include the Durr Vistaproof™ and the Morita Penscope™. The LEDs used in such devices are spectrally broad and also produce some faint light in the visible violet range (400-440 nm).

Figure 2. Demonstration of calculus because of its PP9 fluorescence

To observe fluorescence, optical filters are used which pass the fluorescence wavelengths but not the excitation wavelengths. These filters can range from coloured glass or polymers (such as coloured spectacles) through to the more expensive interference filters made by depositing layer upon layer of dielectric materials onto a glass surface, each of which has different refractive indices. Constructive and destructive interference occurs with different wavelengths of light, causing some to be transmitted through and others reflected back (rejected). For instruments which measure fluorescence, interference filters are typically used.

Plaque and calculus detection UVA light emits visible red fluorescence from deposits of mature dental plaque on the surface of teeth, restorations, or dental appliances.

This has been studied since the seminal work of Bommer and Benedict in the mid-1920's, who first reported the characteristic red fluorescence from dental plaque and dental calculus respectively, when using UVA light sources. The fluorescence arises because of the presence of porphyrin compound, particularly protoporphyrin-IX (PP9), in bacteria. PP9 and similar porphyrin molecules are derivatives of haemoglobin and are involved in the biosynthetic pathway for heme. Because PP9 is found in high amounts in Gram negative oral bacteria, and the levels of Gram negative bacteria increase as the dental plaque biofilm becomes more mature, red fluorescence is associated with mature dental plaque on teeth as well as on appliances such as dentures. Laboratory studies have shown that Actinomyces odontolyticus (found in dentine carious lesions), Bacteroides intermedius, Corynebacterium spp. and Candida albicans all emit at 620-635 nm and 700 nm when excited by 407 nm UVA light, while the Gram positive Streptococcus mutans, Enterococcus faecalis and various lactobacilli are weaker or negative for porphyrin fluorescence in the red spectral region.

Thus, the maturity of dental plaque, rather than the presence of cariogenic streptococci, is the basis for the red fluorescence which occurs with UVA light. The emission of the red light from dental plaque corresponds with known emission peaks of UVA-excited PP9 (Figure 1). As well, the rapid decay of fluorescence once the incoming UVA light is ceased confirms that the process is PP9 fluorescence rather than phosphorescence. PP9 is also excited by visible red light (655 nm) giving near-infrared emissions. This continued on page 17

Figure 3. Visible spectrum (400-700 nm) showing the short wavelengths on the left and long wavelengths on the right.

A wavelength of 405 nm is useful for exciting PP9 fluorescence.

14

ULTRAVIOLET-INDUCED FLUORESCENCE

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

longer wavelength is used in the KaVo DIAGNOdent™ system, which measures fluorescence quantitatively.

In the mid-1920's, Bommer detected an orange and red fluorescence of dental plaque in patients using a UVA light source (Wood's lamp).

Today, this process is fully understood at the molecular level. In short, when dental plaque or calculus is present, there is an increase in the absorption in the UVA spectral region at 350-420 nm, with the appearance of a fluorescence signal in the visible red spectral region at 590-650 nm2-3. Using a polarizing element (to reduce reflection and scatter) and a long pass orange-red filter, these emissions can be seen with the naked eye, and can also be recorded with CCD or CMOS sensors in imaging systems.

Following professional prophylaxis, residual deposits of plaque and calculus appear as red fluorescing areas4. As well as the obvious diagnostic benefits to clinical operators, UVA-induced fluorescence can be used to educate patients and to assist in oral hygiene instruction, since it is not necessary to use disclosing dyes (Figures 2 and 3).

If one wishes to use a dye, UVA is a powerful inducer of bright yellow fluorescence in sodium fluorescein or fluorescein diacetate5-7.

These dyes can be applied topically in the mouth or to dental appliances

Figure 5. Clinical examples of the software in use. Top left, carious molar; Top right; the same area with superimposed fluorescence scores. Note the intensely stained area on the right hand side. Lower left, UVA induced green fluorescence of normal tooth structure, with red PP9 fluorescence from fissures either intra- or extra-orally, and following rinsing the location of the retained dye, can be used to assist in oral hygiene education5-8. UVA can excite other dyes such as the red-maroon compounds rhodamine B and rhodamine 1239-10, giving visible yellow emissions.

Mineral loss and dysmineralization Prior to the first World War, Stubel in 1911 investigated the fluorescent characteristics of various biological tissues when irradiated by ultraviolet light and found that teeth brilliantly fluoresce an intense blue-green colour. Later work showed that the organic (protein) components of tooth structure were responsible for this, rather than the mineral components, with the amino acid tryptophan attracting attention as a natural fluorophore of sound dentine.

With excitation at 375 nm, emission peaks for human enamel occur at 460 (blue) and 560 nm (green). Because of this, areas of mineral loss are readily apparent because of their reduced positive signal.

Thus, under ultraviolet light, enamel with white spot lesions is darker compared to the adjacent luminescent sound enamel. The same method will identify dysmineralization defects which occur during tooth formation, as well as dental fluorosis, which can have a texture and colour similar to those of initial caries lesions but another shape and location11.

Dental caries Figure 4. Dürr Vistaproof system, showing camera (centre), and software (lower right).

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

In white spot lesions, PP9 is trapped in small surface porosities and can be detected because of its fluorescence properties. A recent large ULTRAVIOLET-INDUCED FLUORESCENCE

17

TABLE 1. UVA excitation and emission interactions Sound tooth structure

Excitation 337 nm 375 nm

Bacteria (mature plaque, dental caries)

Supra and subgingival calculus

320-380 nm 407 nm 360-580 nm 655 nm 420 nm

Protoporphyrin IX

407 nm

Sodium fluorescein

400-465 nm

scale clinical trial of this using the DIAGNOdent (which has a detection limit of 1 picomole12, showed detectable fluorescence in buccal white spot lesions on deciduous teeth13. Similarly, once the overlying plaque is removed, dyes applied to the tooth surface will be retained in areas of porous enamel affected by early caries, assisting the identification of these areas by fluorescence, e.g. using sodium fluorescein.

UVA-induced fluorescence can detect more demineralized pre-cavitated enamel areas (white spot lesions) than a conventional visual examination14-16. A significant decrease in the intensity of the fluorescence signal occurs in both demineralized teeth and in teeth with dentine carious lesions17-19. For wavelengths from 400 to 420 nm, carious lesions with cavitations in dentine containing bacteria showed emissions at 600700 nm typical for porphyrin compounds19-20.

Clinical applications The Durr Vistaproof system uses six LEDs emitting at 405 nm and is the ideal wavelength in the UVA waveband for revealing PP9 fluorescence. The image sensor is a 6mm CCD, and the camera optics are shrouded to excluded ambient light when examining a tooth, thus increasing the signal to noise ratio. The shroud also acts as a spacer, giving a constant distance (Figure 4). Captured images from the camera unit are ported back to a computer via a USB 2.0 interface for analysis (Figure 5). The camera is powered from its own source, not

18

ULTRAVIOLET-INDUCED FLUORESCENCE

Emission 430-450 nm 480-500 nm 460 nm 560 nm 590-650 nm 635 nm 600-700 nm 720-800 nm 595 nm 635 nm 650 nm 695 nm 590 nm 620 nm 635 nm 520-530 nm

Colour of emission Light blue Aqua blue Light blue Light green Red Red Red (Infrared) Red Red Red Deep Red Red Red Red Green

via the USB interface, thereby making it suitable for use with laptop computers as well as desktops. The DBSWIN analysis software highlights the intensity of the red signal from PP9, providing a numerical score that can assist treatment decisions, in much the same way as has been done with QLF (Inspektor™) and DIAGNOdent. Toggling between view and analysis modes, and freezing images is a simple task using a footswitch.

TABLE 2. Some dental applications of UVA light

• Detect mineral loss (white spot caries, dental erosion); • Detect dysmineralization (developmental lesions, fluorosis); • Detect carious lesions which involve the DEJ or dentine; • Check caries removal during excavation; • Demonstrate plaque and calculus during patient education; • Visualize plaque and calculus remaining after debridement; and • Reveal bound or trapped marker dyes (porosity/leakage).

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

TM

Goodbye, messy powder and cleanup.

• No hand mixing. Eliminates mess and cleanup. Saves time and material.

• Delivery options. Cartridge or Volume™ automix dispensing.

• Quick set times from start of mix. Cartridge –Work time: 1 minute.

Removal time: 2 minutes 30 seconds. Volume –Work time: 1 minute 15 seconds. Removal time: 2 minutes 45 seconds.

• Fewer impressions needed. A single impression can yield multiple stone pours.

• Impressions remain stable. You can pour immediately or when it’s convenient. Impressions retain dimensional stability for months.

Take 1®

Easy. Precise. Versatile. Hydrophilic.

The closer you look, the better we look.

• Multiple choice. 5 viscosities, 3 set times and 3 delivery methods, including unique Unidose® syringe for wash.

• Proprietary blend of 5 vinyls. Combines with Kerr’s advanced ultra-fine particle filler to provide tensile strength and stretch to flex around undercuts.

• Marginal integrity.

Optimal elongation and tear strength properties deliver enhanced marginal integrity.

• Patented hydrophilic additive. Provides excellent surface energy, resulting in unsurpassed reproduction accuracy even in the presence of moderate blood and saliva.

• Contact angle. Low contact angle releases the surface tension of intraoral fluid, causing it to be dispersed.

KerrHawe SA P.O. Box 268 6934 Bioggio Switzerland Freephone: 00800 41 05 05 05 Fax: ++41 91 610 05 14 www.KerrHawe.com

Your practice is our inspiration.™

REFERENCES 1. Murphy GF, Walsh LJ, Kaidbey K, Lavker RM. Mechanism(s) of dermal endothelial activation elicited by specific regions of the electromagnetic spectrum. Clin Res. 1991; 39:195.

2. Borisova E, Uzunov T, Avramov L. Laser-induced autofluorescence study of caries model in vitro. Lasers Med Sci. 2006;21(1):34-41.

3. Kühnisch J, Heinrich-Weltzien R, Tranæus S, Angmar-Månsson B, Stößer L. Confounding factors in clinical studies using QLF. Int Poster J Dent Oral Med. 2003, 5(2): 177.

4. Coulthwaite L, Pretty IA, Smith PW, Higham SM, Verran J. The microbiological origin of fluorescence observed in plaque on dentures during QLF analysis.

Caries Res. 2006;40(2):112-6.

5. Lang NP, Ostergaard E, Loe H. A fluorescent plaque disclosing agent. J Periodontal Res. 1972;7(1):59-67.

6. Gillings BR. Recent developments in dental plaque disclosants. Aust Dent J. 1977; 22(4):260-6.

7. Gelskey S, Brecx M, Netuschil L, MacDonald L, Brownstone E, Stoddart M. Vital fluorescence: a new measure of periodontal treatment effect. J Can Dent Assoc. 1993; 59(7):615-8.

8. Sagel PA, Lapujade PG, Miller JM, Sunberg RJ. Objective quantification of plaque using digital image analysis. Monogr Oral Sci. 2000;17:130-43.

9. Hart SJ, JiJi RD. Light emitting diode excitation emission matrix fluorescence spectroscopy. Analyst. 2002; 127(12):1693-9.

10. Kuo JS, Kuyper CL, Allen PB, Fiorini GS, Chiu DT. High-power blue/UV lightemitting diodes as excitation sources for sensitive detection. Electrophoresis.

2004; 25(21-22):3796-804.

11. Angmar-Mansson B, de Josselin de Jong E, Sundstrom F, ten Bosch JJ. Strategies for improving the assessment of dental fluorosis: focus on optical techniques. Adv Dent Res. 1994;8(1):75-9.

12. Hibst R, Paulus R, Lussi A. Detection of occlusal caries by laser fluorescence: Basic and clinical investigations. Med Laser Appl. 2001; 16(3):205-13.

13. Walsh LJ, Groeneveld G, Hoppe V, Keles F, van Uum W, Clifford H. Longitudinal assessment of changes in enamel mineral in vivo using laser fluorescence. Aust Dent J. 2006; 51(4): S26.

14. Hafstrom-Bjorkman U, Sundstrom F, ten Bosch JJ. Fluorescence in dissolved fractions of human enamel. Acta Odontol Scand. 1991;49(3):133-8.

15. Angmar-Mansson B, al-Khateeb S, Tranaeus S. Monitoring the caries process. Optical methods for clinical diagnosis and quantification of enamel caries. Eur J Oral Sci. 1996;104 (4 ( Pt 2)):480-5.

16. Stookey GK. Quantitative light fluorescence: a technology for early monitoring of the caries process. Dent Clin North Am. 2005 Oct;49(4):753-70.

17. Sundstrom F, Fredriksson K, Montan S, Hafstrom- Bjorkman U, Strom J. Laser-induced fluorescence from sound and carious tooth substance: spectroscopic studies. Swed Dent J. 1985;9(2):71-80.

18. Borisova EG, Uzunov TT, Avramov LA. Early differentiation between caries and tooth demineralization using laser-induced autofluorescence spectroscopy.

Lasers Surg Med. 2004;34(3):249-53.

19. Subhash N, Thomas SS, Mallia RJ, Jose M. Tooth caries detection by curve fitting of laser-induced fluorescence emission: a comparative evaluation with reflectance spectroscopy Lasers Surg Med. 2005;37(4):320-8.

20. Buchalla W. Comparative fluorescence spectroscopy shows differences in non-cavitated enamel lesions. Caries Res. 2005;39(2):150-6.

Blending Reciprocation with the Creation of Larger Apical Diameters <By Richard E. Mounce*

M

any rotary nickel titanium (RNT) systems can be rotated at higher rpms than the manufacturers recommended speed.

For example, I rotate the Twisted File* (TF) at 900 rpm, the manufacturers recommended rpm is 500. I rotate TF at this rpm with the torque control off. This said, using auto reverse and torque control is a matter of personal preference. The use of higher rpms with any RNT file allows a very light touch and removal of dentin along a narrow band of several mm within the canal (4-6 mm) and to do so in a single insertion of 2-3 seconds followed by withdrawal. Such a motion of insertion is highly efficient and resists the probabilities of file fracture, especially if the insertion is gentle and passive and done to the point of resistance without undue pressure. Higher rpms provide less torsional stress onto the RNT, has less risk of taper lock and give greater tactile control to the clinician.

A glide path should precede the use of all RNT files, including TF. A glide path can be made simply, efficiently and very predictably using the M4 Safety handpiece attachment.* The M4 is a reciprocating handpiece attachment which can take a small hand K file, (#6, 8 or 10 hand K file) and provide a minimal initial enlargement to make way for RNT files. With reciprocation, a small canal, such as can barely accept a #6 or 8 hand K file, can be enlarged in approximately 2 minutes to create a glide path (i.e. a #15 hand K file). Clinically, using the M4, once the small hand file, a #6, 8, 10 is placed to the minor constriction of the apical foramen (MC) (after patency is achieved in the canal), the M4 can be attached onto the hand file, under the rubber dam, and the initial size of hand K file that will negotiate the canal can be enlarged to the next larger hand K file size. For example, a #6 hand K file can be reciprocated to the size of a #8, a #8 can be reciprocated with the M4 to the size of a #10, etc.

The M4 reciprocates a hand K file using a 30-degree clockwise and 30 degree counterclockwise motion mimicking the motion of hand file negotiation and watch winding that is used in the manual creation of this initial enlargement. The use of reciprocation, in the manner described, saves time, minimizes hand fatigue as well as creates a reproducible path for the subsequent RNT files to traverse. The M4 is coupled to an E type attachment on an electric endodontic motor and is utilized with an 18:1 setting at 900 rpm. The vertical amplitude of M4 movement is 1-3 mm and bursts of reciprocation last approximately 15-30 seconds. As the hand K file reciprocates, the file will become less bound in the canal and vertical movement will become freer as enlargement progresses.

While some clinicians advocate the use of reciprocation for the entire preparation and do not advocate the use of RNT, the global standard for canal preparation is RNT and TF is recommended here for its attributes, which include: 1) the creation of larger tapers to the apex. Routinely, a .08 taper can be taken to the apex of moderate to severe curvature.

2) fewer insertions are needed to insert TF to the apex.

3) significant flexibility and fracture resistance relative to RNT files that are manufactured by grinding. TF is manufactured by twisting nickel titanium that has been placed into the R phase of crystalline phase configuration, an intermediate phase between austenite and martensite.

4) the ability to prepare approximately 1/3 of the roots encountered with one single file, 1/3 of the roots encountered with two files and the remainder of the roots with three TF instruments.

TF insertion should be gentle, passive and generally to resistance and removed, when in doubt, TF should not be forced further apically in

*DDS. Private endodontic practitioner, Vancouver, WA, USA.

22

BLENDING RECIPROCATION WITH THE CREATION OF LARGER APICAL DIAMETERS

Correspondence address: Lineker@comcast.net Vancouver, WA, USA

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

the canal. Generally, the next smaller TF taper should be used if any given TF does not want to move apically without undue pressure. TF, like most RNT files, is not used with a pecking motion. Once preparation of the canal has been completed to a final taper often a .08 taper or larger with TF, the master apical diameter can be determined and prepared.

Dr. Mounce offers intensive customized endodontic single day training programs in his office for groups of 1-2 doctors. For information, contact Dennis at 360-891-9111 or write: RichardMounce@MounceEndo.com Dr. Mounce lectures globally and is widely published. He is in private practice in Endodontics in Vancouver, WA, USA.

The final master apical diameter that should be created is a matter of great debate globally. There are numerous empirical concepts that have traditionally guided a decision as to what the final prepared diameter might be. These concepts have included using the first file that binds at the apex (usually determined empirically based on an x-ray).

This first binding file is used as a guide from whom the final master apical diameter is determined, this being three sizes larger than the aforementioned first file.

Using hand files to create an enhanced master apical diameter is now antiquated in a clinical spectrum that includes RNT files for canal preparation and the modern use of electronic apex locators. It is highly predictable to determine the exact position of the MC and to approximate the initial diameter of the MC using a technique such as gauging.

Figure 1: The M4 Safety Handpiece

Irrespective of the RNT files used, the endodontic literature shows that the creation of larger apical diameters is superior to smaller apical diameters in creating canal cleanliness. While there are many techniques for creation of enhanced apical diameters, a typical method is to gauge the apical foramen to get an initial diameter of the MC and then enhance the MC to a larger size. Gauging gives the clinician some rough approximation of the initial diameter of the MC and as such informs the clinician what the final prepared diameter might be.

For example, if a #25 hand file does not advance past the MC, this is a rough measure of the diameter of the canal and the canal can be enlarged to a #40 or perhaps larger diameter. Using a system like TF, if the basic preparation created is a .06 25, and the canal gauges to a #25, a smaller taper such as a .04 K3* or .02 K3* can be placed into the larger taper, cutting will only occur on the end of the instrument and prepare the larger apical diameter. In this example, the sequence of instrumentation is a .04 25, 30, 35, 40, etc to the desired apical diameter. Once the canal preparation has been optimized, the clinicians chosen method can obturate the canal.

Figure 2: The Twisted File (SybronEndo, Orange, CA, USA)

A clinically relevant discussion of the use of reciprocation and the creation of larger apical diameters has been presented. Emphasis has been placed on achieving patency, the value of mechanically creating the glide path using reciprocation and the value of preparing larger apical diameters. Figure 1-4.

I welcome your questions and feedback. *SybronEndo, Orange, CA, USA Dr, Mounce does not have a financial interest in any of the products discussed in this article.

24

Figure 3-4: Clinical cases using the concepts discussed in this article

BLENDING RECIPROCATION WITH THE CREATION OF LARGER APICAL DIAMETERS

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Micro-tensile bond strength of one-step adhesives to dentin <By Khalid M. Abdelaziz Ph.D*, Neveen M. Ayad Ph.D**

ABSTRACT

INTRODUCTION

Purpose: To evaluate the micro-tensile bond strength of 2 one-step adhesive systems and a 1 two-step etch-and-rinse to dentin before and after thermal cycling.

Materials and Methods: Occlusal surfaces of 30 extracted human molars were prepared using diamond tips to expose flat dentin surfaces. Two one-step, G-Bond (GB) and Adper Prompt L-Pop (APL), and 1 two-step, Excite (Ex), adhesive systems were applied to bond composite to the prepared dentin surfaces. The prepared specimens were sectioned for micro-tensile bond strength testing (µTBS). The de-bonding patterns of the fractured specimens were also analyzed.

Results: The one-way ANOVA test indicated presence of differences between the bond strength of different adhesives to dentin before and after thermal cycling (ANOVA, p < 0.001). There was no statistical difference between the 2 one-step adhesives (Tukey's comparison, P > 0.05) before or after thermal cycling. This difference was not statistically significant (Tukey's comparison, P > 0.05) when the bond strength of unthermal-cycled G-bond was compared with the control (Excite) or the thermal-cycled G-bond was compared with the thermal-cycled (Excite). The admix (adhesive/cohesive) de-bonding was the dominant pattern of specimens' failure.

Conclusion: The one-step adhesive APL does not perform worse regarding µTBS, (16.3 ± 2.7) than the newer one GB (18.4 ± 4.9). The µTBS of GB is also comparable to that of the control, Ex two-step adhesive (20.9 ± 2.4). Thermal cycling has no statistically significant deteriorating effect on the performed bond of different adhesives under investigation, APL-Th (13.1 ± 1.2), GB-Th (14.7 ± 2.4), Ex-Th (18.4 ± 1.7).

Restoring teeth with minimal sacrifice of sound tooth structure currently forms the basis of restorative dentistry. Essential in achieving this goal is the adhesive that provides strong and durable bond to the remaining sound tooth tissues especially when shrinking materials such as resin composites are planned to be used.1, 2 The early successful adhesive systems have typically accomplished resin-dentin bonding in three steps respectively are the etching, priming, and application of bonding resin.3 Using these systems, the quality of the created bond is greatly influenced by the duration of the etching process, and by the amount of dentin surface humidity following rinsing of the etching acid and prior to resin infiltration. 4 Therefore, most of the recent researches and developments in dentin adhesion are directed to simplify the bonding procedures and to eliminate all possible technical sensitivities by reducing the number of bonding steps. These developments have been started when the primer and bonding resins were combined together in one bottle.

The self-etching primers were then released with the ability to etch and prime the dentin in one step.4, 5 The self-etching approach seemed promising as it reduces the chairside time, and eliminates the critical and difficult standardization of the bonding steps.6 The one-step self-etch adhesives were subsequently introduced simplifying the conditioning, priming, and bonding procedures just in a single step. However, the early types of these adhesive systems seemed to achieve lower bond strength values in comparison to the two-step systems.7, 8 Newer types of the one-step self-etching adhesive systems have recently been introduced to the market claiming to have higher bond strength via formation of an

* Lecturer of Dental Biomaterials, Suez Canal University, Faculty of Dentistry, Ismailia, Egypt. Consultant in Conservative Dentistry and Dental Materials, Gizan, Dental Center, Gizan, KSA **Lecturer of Dental Biomaterials, Faculty of Dentistry, Mansoura University, Egypt DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

MICRO-TENSILE BOND STRENGTH OF ONE-STEP ADHESIVES TO DENTIN

27

unusual very thin interaction layer.9, 10 A conflict was raised regarding the success of these new one-step self-etching (all-in-one) adhesives as it depends on the specific composition of each product. Therefore, it was suggested that these new adhesives are in need for more screening before recommending them for clinical use.11 The micro tensile test is increasingly used to evaluate the strength of such tooth-adhesive bond12, 13, 14, 15 This test provides a purely tensile load on a very small cross-section of the bonding interface regardless the specimens' design.16 Over such a limited surface, stress distribution is expected to be uniform, thus enabling the test measurements to truly express the interfacial bond strength.13, 14, 15 In addition, the micro tensile method has allowed the mapping of bond strength in different regions or at different depths of dental tissues.17, 18 To stand on the efficiency of the new all-in-one adhesives bonding to dentin, this in vitro study aimed to evaluate the micro-tensile bond strength (µTBS) of 2 one-step self-etching adhesive systems to dentin before and after thermal cycling. The bond strength of a 1 two-step adhesive system was also considered to act as control. A microscopic analysis of the fractured surfaces was also carried out to detect the exact mode(s) of bond failure.

MATERIALS AND METHODS Thirty caries-free freshly-extracted human molars were selected for this study. The collected teeth were cleaned (Pro-sonic 300 MTH, Sultan Chemists Inc, Englewood, NJ) and stored in de-ionized water that contained antibacterial agent (0.2% sodium azide) for a maximum of one month before trimming their occlusal anatomy (LabMaster, Ray Foster Dental Equipment, Huntington Beach, CA) to prepare flat dentin surfaces. The flattened surfaces were then finished using long cylindrical diamond tips (F31273, EDENTA GmbH, Lustenau) mounted to high speed handpiece. Immediately after finishing and before performing the bonding procedure, the flat dentin TABLE 1. Materials used in this study Material Description I. Adhesive systems: G-Bond (GB) 1-step, Self-etch adhesive Adper Prompt L-Pop (APL)

1-step, Self-etch adhesive

Excite(Ex)

2- step, etch and rinse adhesive

II. Restorative material: Tetric Ceram Light-curing, fine-particle hybrid resin composite

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

surfaces were subjected to thorough cleaning using air-water spray.

The prepared teeth were dried with air then equally divided into 3 main groups (n=10 for each adhesive system). The description and manufacturers of the materials used are shown in Table 1 For the control group; one 2-step single component adhesive system Excite was used to retain the Tetric Ceram composite to dentin. The flat surfaces of the prepared teeth were etched using 37% phosphoric acid (Vivadent, Schaan, Liechtenstein) for 15 s, washed under copious air-water spray and gently dried using cotton pellets. Two successive coats of the single component resin adhesive were then applied to the moist dentin surfaces using a brush for 10 s and cured by the aid of Hawe-Neos halogen light-curing device (Gentilino, Switzerland) providing intensity of 600 mW/ cm2 for another 20 s after air drying of the excess material. Two one-step, self-etch (GBond); and (Adper Prompt L-Pop) adhesive systems were used in the other 2 groups. The self-etch bonding resins were applied to the prepared dentin surfaces and left for 10s before air thinning. Curing of both self-etching adhesives was performed using the same light-curing device for 10s.

The composite material was then incrementally built up to be 2 mm above the flat occlusal surfaces. Each increment was light-cured for 40 s and a rubber mold 8 mm in diameter and 2 mm high, situated over the flat occlusal plane of each prepared tooth, aided in both building and contouring the composite restoration. The restored teeth were incubated in water at 37±1oC for 24 h and half of them (5 teeth from each group) were also subjected to thermo-cycling (Th) (Willytec Thermocycler 10714, Munich, Germany) at 5oC, 37oC and 55oC for 5000 cycles with 30-s dwell time resulting in 6 groups.19, 20

Micro-tensile bond strength testing Roots of the restored teeth were implanted in plastic rings, 1.5 cm in diameter, by means of self-cured acrylic resin (Duracrol, Spofa-Dental,

Composition

Manufacturer

Phosphoric acid ester monomer, UDMA, 4MET, TEGMA, acetone, water, initiators Compartment 1 : Methacrylated phosphoric acid esters, photoinitiator, stabilizers Compartment 2 : Water, HEMA, polyalkenoic acid, stabilizers HEMA, DMA, phosphoric acid acrylate , highly dispersed silicone dioxide, initiators and stabilizers in alcohol solution

GC America, St. Alsip, IL, USA

BisGMA, UDMA, TEGDMA, ytterbium trifluoride, barium glass , pigments and initiators

Ivoclar Vivadent

3M/ESPE Dental Products, St. Paul, MN, USA

Ivoclar Vivadent, Schaan, Liechtenstein

MICRO-TENSILE BOND STRENGTH OF ONE-STEP ADHESIVES TO DENTIN

31

Prague, Czech Republic). These rings kept the teeth properly oriented at the time of sectioning. The composite build-ups and the underlying dentin were sectioned in both buccolingual and mesiodistal directions. The sectioning process was carried out the same way as that of El-Kholaney et al., 21 using diamond disks (Edenta Gmbh, Lustenau, Austria) in straight handpiece fixed to a specially-designed benchmounted orienting apparatus, under air-water spray cooling. The cutting process resulted in sticks of nearly 1 mm2 cross-sectional area. The sticks were then separated from the dentin base and carefully observed to select 10 sticks from each group of samples. The selected sticks were again incubated for 24 h before conducting the bond strength testing. The exact dimensions of each stick were measured using a digital caliper (Model CD-S6 CP, Mitutoyo Corp., Japan) before they were affixed with Zapit-brand cyanoacrylate adhesive (Dental Ventures of America, Ventura, USA) to the specially designed jigs of the universal testing machine (Type 500, Lloyd instrument, England). Sticks were stressed to failure under tension at a crosshead speed of 2mm/min. The micro-tensile bond strength for each sample was calculated in MPa by dividing the maximum force at fracture in Newton by the sample's cross-sectional area in mm2.

Assessing the mode of specimens' fracture The 2 parts of the tested sticks were evaluated for the mode of bond failure using a stereoscope microscope (Olympus Zoom Stereomicroscope, Sz 40-45 TR, Japan) at 30◊ original magnification.

The evaluation process took place by every author included in this study. Their results were compared and the detected differences were discussed before nominating one author to reexamine the sticks for the second time considering his results as final. The detected modes of failure were classified as adhesive when the fracture site was entirely within the adhesive/ dentine or adhesive/ composite interface; cohesive, when the fracture occurred exclusively within the resin composite or dentin; or mixed when the fracture site continued from the adhesive into either the resin composite or dentin. Some fractured samples (n=5) were randomly selected for further scanning electron microscopic observation (SEMx1000) at 30 KV (JEOL, JSM, 5600LV, Tokyo, Japan).

Statistical analysis Bond strength data of the thermal-cycled and un-thermal-cycled samples of all groups were subjected to statistical analysis using SPSS statistical package version 10 one-way ANOVA (P= 0.05) to detect any differences existing between the adhesive systems under both conditions. The Tukey's comparisons (P= 0.05) were then used to show the significance of those differences detected between all groups.

RESULTS Means and standard deviations of the recorded micro-tensile bond strengths are shown in table 2. The one-way ANOVA (Table 2) indicated presence of significant differences (p < 0.001) between the bond strength values of different adhesives to dentin before and

32

MICRO-TENSILE BOND STRENGTH OF ONE-STEP ADHESIVES TO DENTIN

TABLE 2. Microtensile bond strength in MPa of different adhesives Groups Ex APL GB Ex-Th APL-Th GB-Th Bond strength 20.9 16.3 18.4 18.4 13.1 14.7 values ± SD ± 2.4 ± 2.7 ± 4.9 ± 1.7 ± 1.2 ± 2.4 Excite (Ex), Adper L-Pop ( APL), G-Bond (GB) and Thermocycling (Th)

after thermal cycling. No statistical difference was detected between the 2 one-step adhesives (Tukey's comparisons, P > 0.05) under the same testing conditions (Table 3), APL (16.3 ± 2.7 MPa), APL-Th (13.1 ± 1.2 MPa), GB (18.4 ± 4.9) and GB-Th (14.7 ± 2.4). This difference was not statistically significant (Tukey's comparison, P > 0.05) when the bond strength of unthermal-cycled G-bond was compared with the control Excite (20.9 ± 2.4) or the thermal-cycled G-bond was compared with the thermal-cycled Excite (18.4 ± 1.7). Both adhesive and admix (adhesive/cohesive) types of bond failure were evident as revealed by the stereomicroscope, (Figure 1). However, SEM images (Figures 2a-c) indicated that the majority of bond failures belong to the admix pattern.

DISCUSSION Adhesion to tooth structure usually provides a great opportunity for more conservative restorations.2 However, the successful adhesive should fulfill the minimal acceptable level of bond strength that helps to resist both polymerization and thermal stresses at the bonding interface.22 Recently, a great concern about technique sensitivity and time consuming of adhesives has been developed and this has initiated the development of newer generations with reduced application steps.23 Accordingly, this in vitro study is concerned with the evaluation of micro-tensile bond strength of two one-step adhesive systems, APL and GB, in comparison to a one two-step type, Ex. The micro-tensile bond strength test was selected for that purpose because of its expected accuracy in comparison to other bond strength tests.12, 13 The recorded data revealed that the µTBS value of GB adhesive was comparable to that of the Ex (Control) and to that of APL, whereas the µTBS value of APL adhesive was lower than that of Ex (Tables 2, 3). These findings coincide with the results of many studies 2, 7, 24, 25 and may be explained as follows; the higher bonding efficiency of Ex is almost dependent on the formation of hybrid layer, in addition to the direct penetration of both dentin micro-irregularities and the opened dentinal tubules.26 Presence of alcohol in the Ex formulation also TABLE 3. Tukey's comparisons between different groups Groups Ex APL GB Ex-Th APL-Th GB-Th

Ex 0

APL GB 0.04493* 0.5731 0 0.7234 0

Ex-Th 0.5489 0.7456 1 0

APL-Th 0.00022* 0.2805 0.01245* 0.01376* 0

GB-Th 0.00255* 0.8783 0.1495 0.1611 0.8932 0

* Significantly different groups

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

CONCLUSION Within the limitation of this study, the one-step adhesive APL does not perform consistently worse regarding µTBS (16.3 ± 2.7) than the newer one GB (18.4 ± 4.9). The µTBS of GB is also comparable to that of the control, Ex two-step adhesive (20.9 ± 2.4). Thermal cycling has no statistically significant deteriorating effect on the performed bond of different adhesives under investigation, APL-Th (13.1 ± 1.2), GB-Th (14.7 ± 2.4), Ex-Th (18.4 ± 1.7).

Fig.1 Percentage of bond failure helps the infiltration of adhesive resin into the collapsed collagen network and accordingly improves the adhesive's bond strength.3 Combining both the etching and bonding procedures in one step can deteriorate the bond as recorded in previous studies7, 24 Those studies related the reduction in bond strength to the presence of etching material and outcomes within the formed dentin/adhesive interaction layer. However, with using GB, functional monomers contained in the bonding material react with hydroxyapatite to form insoluble calcium, forming a thin transitional zone that may be responsible for improving its bond strength.9, 27, 28, 29 Subjecting some specimens to thermal cycling before performing such bond strength testing has been recommended in many in vitro studies.7, 19, 30 Application of heat and cold alternatively usually gives a crude indication about the efficiency and longevity of such bonds in service. Similar to other studies,7, 19, 31 a reduction in bond strength values of the tested adhesive systems was found after thermal cycling, but the difference in this study was not statistically significant (Tukey's comparison, P > 0.05) probably because of the relatively short-term application of thermal cycling. The reduction in µTBS values could be related to the fatigue of the already existing bond. Bond fatigue may be developed as a result of thermal stresses that developed at the bonding interfaces because of the differences in coefficient of thermal expansion of materials sharing those interfaces.

32However, the little effect of both thermocycling and water immersion on the bond strength values of GB could be attributed to the minimal thickness of the adhesive junction.2, 5, 20 The adhesive and admix (adhesive/cohesive) modes of bond failure were revealed in the results of this study (Figure 1), which coincide with other studies.4, 33, 34, 35 The suggestion is that the presence of both etching material and products of the etching process within the adhesive layer weaken mechanical properties of such resin. These remnants own different elastic moduli and coefficients of thermal expansion than those of dentin and composite material. These differences could initiate microcracks within the adhesive layer at the time of specimens' cutting and testing. Therefore fracture of the adhesive body could be expected more frequently with the self-etching adhesives in comparison to the 2 step adhesives those always free of etching remnants.7

34

MICRO-TENSILE BOND STRENGTH OF ONE-STEP ADHESIVES TO DENTIN

Fig. 2 SEM Photographs (x 1000) of specimens after µTBS testing demonstrating a mixed failure mode (adhesive/cohesive). (a) GBbonded specimen. (b) APL-bonded specimen showing cracks in the adhesive layer (pointer) as well as voids at the interface (arrows). (c) Ex-bonded specimen. Hybrid layer (H) Adhesive layer (A)

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

REFERENCES 1. Nikolaenko SA, Lohbauer U, Roggendorf M, Petschelt A, Dasch W, Frankenberger R (2004): Influence of c-factor and layering technique on microtensile bond strength to dentin. Dent Mater., 20:579-585.

2. Shirai K, De Munck J, Yoshida Y, Inoue S, Lambrechts P, Suzuki K, Shintani H, Van Meerbeek B (2005): Effect of cavity configuration and aging on the bonding effectiveness of six adhesives to dentin. Dent Mater., 21:110-124.

3. Van Meerbeek B, De Munck J, Yoshida Y, Inoue S, Vargas M, Vijay P, Van Landuyt K, Lambrechts P, Vanherle G (2003): Buonocore memorial lecture. Adhesion to enamel and dentin: current status and future challenges. Oper Dent., 28:215-235.

4. El Zohairy AA, De Gee A J, Mohsen MM, Feilzer AJ (2005): Effect of conditioning time of self-etching primers on dentin bond strength of three adhesive resin cements. Dent Mater., 21:83-93.

5. Armstrong SR, Vargas MA, Fang Q, Laffoon JE (2003): Microtensile bond strength of a total-etch 3-step, total-etch 2-step, self-etch 2-step, and a self-etch 1-step dentinbonding system through 15-month water storage. J Adhes Dent., 5:47-56.

6. Van Landuyt KL, Kanumilli P, De Munck J, Peumans M, Lambrechts P, Van Meerbeek B (2006): Bond strength of a mild self-etch adhesive with and without prior acid etching. J Dent., 34:77-85.

7. Frankenberger R, Tay RF (2005): Self-etch versus etch-and-rinse adhesives: effect of thermo-mechanical fatigue loading on marginal quality of bonded resin composite restorations.

Dent Mater., 21:397-412.

8. Ozok AR, Wu MK, De Gee AJ, Wesselink PR (2004): Effect of dentin perfusion on the sealing ability and microtensile bond strengths of a total-etch versus an all-in-one adhesive. Dent Mater., 20: 479-486.

9. Product pamphlet, GC G-Bond, Advanced Seventh Generation Bonding, GC America Inc., USA 10. Sidhu, S K, Omata Y, Tanaka T, Koshiro K, Spreafico D, Semeraro S, Mezzanzanica D, Sano H (2007): Bonding characteristics of newly developed all-in-one adhesives. J Biomed Mater Res B Appl Biomater., 80: 297-303.

11. Perdigao, J., Gomes G, Gondo R, Fundingsland JW (2006): In vitro bonding performance of all-in-one adhesives. Part I--microtensile bond strengths. J Adhes Dent., 8: 367-373.

12. Pashley DH, Carvalho RM, Sano H, Nakajima M, Yoshiyama M, Shono Y, Fernands CA, Tay FR (1999): The microtensile bond test: a review. J Adhes Dent., 1:299-309.

13. Sano H, Shono T, Sonoda H, Pashley DH (1994): Relationship between surface area for adhesion and tensile bond strength-evaluation of a microtensile test. Dent Mater., 10:236240.

14. Purk JH, Healy M, Dusevich V, Glaros A, Eick JD (2006): In vitro microtensile bond strength of four adhesives testedat the gingival and pulpal walls of Class II restorations. J Am Dent Asso., 137:1414-1418.

15. Sano H (2006): Microtensile testing, nanoleakage, and biodegradation of resin-dentin bonds. J Dent Res., 85:11-15.

16. Betamar, N., G. Cardew, Van Noort R (2007): Influence of specimen designs on the microtensile bond strength to dentin. J Adhes Dent., 9: 159-168.

17. Yoshiyama M, Carvalho RM, Sano H, Horner JA, Brewer PD, Pashley DH (1996): Regional bond strength of resin to human root dentin. J Dent Res., 74:435-442.

18. Yoshiyama M, Sano H, Ebisu S, Tagami J, Ciucchi B, Carvalho RM, Johnson MH, Pashley DH (1996): Regional bond strength of bonding agents to cervical sclerotic root dentin. J Dent Res., 75:1404-1413.

19. Nikaido T, Kunzelmann KH, Chen H, Ogata M, Harada N, Yamaguchi S, Cox CF, Hickel R, Tagami J (2002): Evaluation of thermal cycling and mechanical loading on bond strength of a self-etching primer system to dentin. Dent Mater., 18:269-275.

20. Price RB, Derant T, Andreou P, Murphy D (2003): The effect of two configuration factors, time, and thermal cycling on resin to dentin bond strengths. J Biomaterials., 24:10131021.

21. El-Kholany NR, Abdelaziz KM, Zaghloul NM, Aboulenien N (2005): Bonding of singlecomponent adhesive to dentin following chemomechanical caries removal. J Adhes Dent., 7:281-287.

22. Feilzer AJ, De Gee AJ, Davidson CL (1987): Setting stress in composite resin in relation to configuration of the restoration. J Dent Res., 66:1636-1639.

23. Koh SH, Powers JM, Bebermyer RD, Li D (2001): Tensile bond strengths of fourth-and fifth-generation dentin adhesives with packable resin composite. J Esthet Restor Dent., 13:379-386.

24. De Munck J, Van Meerbeek B, Yoshida Y, Inoue S, Vargas M , Suzuki K, Lambrechts P, Vanherle G (2003): Four-year water degradation of total-etch adhesives bonded to dentin.

J Dent Res., 82:136-140.

25. Hannig M, Bock H, Bott B, Hoth-Hannig W (2002): Inter-crystallite nanoretention of selfetching adhesives at enamel imaged by transmission electron microscopy. Eur J Oral Sci., 110:464-470.

26. Van Meerbeek B, Inokoshi S, Braem M, Lambrechts P, Vanherle G (1992): Morphological aspects of the resin-dentin interdiffusion zone with different dentin adhesive systems. J Dent Res., 72:1530-1540.

27. Hiraishia N, Breschi L, Prati C, Ferrari M, Tagami, King NM (2007): Technique sensitivity associated with air-drying of HEMA-free, single-bottle, one-step self-etch adhesives. J Dent Mater., 23:498-505.

28. Spencer P, Wang Y (2002): Adhesive phase separation at the dentin interface under wet bonding conditions. J Biomed Mater Res., 62: 447-456.

29. Tay FR, King NM, Chan KM, Pashley DH (2002): How can nanoleakage occur in selfetching adhesive systems that demineralize and infiltrate simultaneously? J Adhes Dent., 2: 255-269.

30. Lee SY, Chiang HC, Lin CT, Huang HM, Dong DR (2000): Finite element analysis of thermo-debonding mechanism in dental composites. J Biomaterials., 21:1315-1326.

31. Mitsui FH, Peris AR, Cavalcanti AN, Marchi GM, Pimenta LA (2006): Influence of thermal and mechanical load cycling on microtensile bond strengths of total and self-etching adhesive systems. Oper Dent., 31:240-247.

32. Craig RG, Powers JM (2002): Restorative Dental Materials. 11th ed. Mosby, Inc., 53-54.

33. Carvalho RM, Pegoraro TA, Tay FR, Pegoraro LF, Silva NRFA, Pashley DH (2004): Adhesive permeability affects coupling of resin cements that utilize self-etching primers to dentin. J Dent., 32:55-65.

34. Cho BH, Dickens SH (2004): Effect of the acetone content of single solution dentin bonding agents on the adhesive layer thickness and the microtensile bond strength. Dent Mater., 20:107-115.

35. Jacques P, Hebling J (2005): Effect of dentin conditioners on the microtensile bond strength of a conventional and a self-etching primer adhesive system. Dent Mater., 21:103-109.

The XIIth International Symposium on Dentofacial Development and Function Cairo, October 16-18, 2008

The XIIth International Symposium on Dentofacial Development and Function was held in the historic hotel “Cairo Marriott Hotel” in Cairo in October 16-18, 2008. Abbas Zaher, professor of orthodontics at the University of Alexandria, Egypt and Vice-President of the WFO presided the meeting.

The scientific program, orchestrated by Prof. Yehia Mostafa, Head of the Department of Orthodontics at Cairo University and successfully coordinated by Prof.

Khaled Attiya from the same department, managed to attract an honorable slate of 21 invited speakers from the seven continents of the world, and thus tackling the most important topics discussed in the field of Orthodontics and Dentofacial orthopedics.

The symposium was preceded by a continuing education course and followed by two, covering most up-todate clinical arenas: Prof. Bjorn Zachrisson from Norway had a heavily attended pre-symposium course on finishing, adult orthodontics and multidisciplinary treatment. Following the symposium, Prof. Robert Vanarsdall, head of department of orthodontics in Pennsylvania University, presented the state-of-the art in orthodontic and periodontic conjunctive treatment modalities. This course attracted the participation of many periodontists and steered up most fruitful discussions. At the same time, Dr. Vitorrio Cacciafesta from Italy taught a large group of 50 orthodontists how to practice the lingual technique with 2D lingual bracket system in a theoretical and practical course.

This esteemed group of world renowned lecturers, together with another 31 speakers whose oral presentation were accepted, attracted more than 400 participants from 34 countries from all over the world.

Alongside the symposium, the presidents of the previous meetings, who attended the symposium, held a meeting to organize the coming event. Prof. Samir Bishara from USA, Prof. Athanasios E. Athanasiou from Greece, Prof. Hans Sergl from Germany, Prof. Kurt Faltin from Brazil, Prof. Nejat Erverdi from Turkey and Prof. Giuseppe Siciliani from Italy and Prof. Abbas Zaher, the president of this Symposium. The Board decided to elect Prof. Siciliani President of the XIIIth International Symposium to be held in Verona, Italy on October 8 - 10, 2010.

Foreign Delegates in front of the Cairo Symposium poster.

Dr. Shaikh from Pakistan presenting her lecture

Dr. Zachrisson engaged in discussion following his course

36

THE XIITH INTERNATIONAL SYMPOSIUM ON DENTOFACIAL DEVELOPMENT

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Dr. Abbas Zaher, Symposium President addressing the guests at the welcome reception

Meeting of the higher council of the Arab Orthodontic Society

Drs. Aboul Azm, Bishara and George chairing the scientific session

Speakers of the first session; Dr. White, USA, Turpin, Editor of AJODFO, Dr. Feteih, KSA and Dr. Bishara, USA

(left to right) Dr. Shaikh from Pakistan, Dr. Bishara, USA, Dr. Khan from Pakistan and Dr. Attia from the Organizing Committee.

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Picture from the trade exhibition

THE XIITH INTERNATIONAL SYMPOSIUM ON DENTOFACIAL DEVELOPMENT

37

TM

IMPLANT SYSTEM

simply efficiency THE IMPLANT

WITHOUT CONNECTING SCREW

EXACONE™ CONNECTION

OUR PROJECT PERFECT BACTERIA-PROOF SEALING

The EXACONE™ connection, thanks to the Morse cone self-locking properties and the maximum resistance to torsion provided by the internal hex, ensures:

investments, research, clinical experience, technology

OUR TARGET is to furnish to the clinician an implant without unscrewing problems and risks of breaking

• total stability, absence of gaps and micro movements

• accuracy of transfer between the dentist's office and the lab • safety, simple, effective junction of fixture and abutment.

LEONE S.p.a - Orthodontics and Implantology Via P. a Quaracchi, 50 - 50019 Sesto Fiorentino (Firenze) Italy Phone +39.055.30.44.620 Fax +39.055.30.44.05 e-mail: info@leone.it - www.leone.it

OUR ACHIEVEMENT Leone dental implants look like natural teeth and are made up of only two parts: fixture and abutment

PP07/2-IN

• high resistance to occlusal loads

PRESIDENT'S STATEMENT

SCIENTIFIC CHAIRPERSON'S STATEMENT

Prof. Antoine Karam President of the Lebanese Dental Association

Prof. Antoine Berberi Chairperson Scientific Committee

Dear Colleagues, It is my pleasure and honor to welcome all of you to our panarab and international convention that is taking place in the country of love, traditions, and knowledge.

We expect all of you to exchange ideas, expertise, and friendship and this is our only real message that we would like to convey to our speakers and participants.

On behalf of our committees and lebanese dentists, we again welcome you and invite you to enjoy the meeting and beauty of our country.

Dear Colleagues, On behalf of BIDM 2008 Scientific Committee, I have the pleasure to introduce the scientific program.

“The Evidence in Clinical Dentistry” is a concept that we have prepared for our 18th Scientific Meeting, taking place at Dbayeh Congress Palace, in Beirut's Northern suburb.

This program ensures three exciting days with renowned speakers addressing recent evidence-based advances on highly relevant topics in dentistry.

Response of the speakers has exceeded our highest expectations. We are proud that our program comprises more than 70 lectures, 5 live transmissions, 16 workshops, and 13 posters, with the participation of 28 invited speakers from 17 countries.

We are convinced that it will be a great opportunity for you to listen, share experiences, and have a pleasant time with colleagues from all over the world. It is an honor for us, indeed, to have you as one of our distinguished participants.

I wish to welcome all of you to “The Evidence in Clinical Dentistry” convention, and remember that this is about interaction, so please take the opportunity to share evidence-based clinical news with our Lebanese lecturers and foreign invited speakers.

Prof. Antoine Karam President, LDA/BIDM 2008

Prof. Antoine Berbéri, Chairperson, Scientific Committee, LDA/BIDM 2008

The Audience during the opening ceremony

40

BIDM 2008

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Foreign Delegates in front of the conference center in Dbayeh

Dr. Mohammed Ben Hafeed (middle) chairman of Yemen's Dentists Syndicate

LDA president prof. Karam giving the Trophy to the Minister of Health Dr. Khalifeh DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Dr. Nadim Baba receiving the trophy for his lecture about CAD/CAM BIDM - 2008

41

The President of the LDA offering trophies to:

44

Dr. Philippe Khayat for his lecture about Implant Dentistry

Dr. Hassan El Halawany representing the Saudi Dental Society

Prof. Raymond George President of the American Association of Orthodontists

Dr. Samir El Kodah, from the Jordanian Dental Association

Prof. Mohammad Nabil Mawsouf for discussing Ozone in Dentistry

Dr. Ali Jamal, Kuwait Dental Association

Dr. Mourad Abdel Salam, President of the Egyptian Dental Association

Dr. Sultan El Harithy, President of the Oman Dental Society

BIDM - 2008

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Dr. Adel Ben Smedah, Representative of Tunisia

Dr. Rajaa Kazem, President of the Bahrain Dental Society

Dr. Mounir Amro from Jordan

The board members of the Lebanese Dental Association cutting the celebratory cake

46

BIDM - 2008

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

®

VITA Easyshade Compact – The exact shade in the blink of an eye. of

dig

ita The l t ne oo w th sh gen ad era e d tio ete n rm ina

tio

3384 E

n

It's digital, cable-free, lightweight and mobile – there are a good

designed for all shades of the VITA SYSTEM 3D-MASTER and the

many reasons for choosing the VITA Easyshade Compact. And

VITAPAN classical A1-D4 shades. This high-tech instrument

every one of these is in itself a winner. With the new generation

impresses with a great accuracy of measurement using state-of-

of digital shade measurement you determine and check the tooth

the-art spectrophotometric measurement technology. See for

shade in a matter of seconds. The VITA Easyshade Compact is

yourself. Find out more at www.vita-zahnfabrik.com.

EXHIBITION FLOOR

48

BIDM - 2008

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

EXHIBITION FLOOR 50

BIDM 2008

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

October 22nd & 23rd 2008 - Monroe Hotel, Beirut

3i Mena (Member of G.Tamer Holding) has organized it 2nd Regional Symposium on October 22nd & 23rd 2008 at the Monroe Hotel, Beirut.

200 dentists from Lebanon & the Region (Saudi Arabia, Emirates, Egypt, Iran, Jordan, Syria & Kuwait) attended the event in the presence of the EMEA Distributors Director Mrs. Michelle Duval.

The attendance has shown a huge interest to the lectures of Dr. Ronald Schimming from Switzerland who talked about the Bone Atrophy in The Edentulous Maxilla, & Dr. Steward Jacobs from The United Kingdom Who talked about the Provisionalisation & Restorative options for Dental Implants, as well as the Lebanese speakers Dr. Georges Hage & Dr. Gerard Tabourian, who talked about different subjects in Bone Regeneration, Esthetic & Prosthetics.

Biomet 3i presented a collection of its novelties, mainly its top implant the Nanotite Tapered Prevail which is a unique system, and its Navigator kits, a region's premiere in the CAD/CAM technology for dental implants.

Biomet 3i team cutting the cake after successfully organizing the conference.

Trophy distribution from G.Tamer Holding to the foreign lecturers

52

BIOMET 3I 2008

Dr. Ronald Schimming and Dr. Steward Jacobs DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

RD #!$ #!- #/-054%2):%$ $%.4)3429 ).4%2.!4)/.!, #/.&%2%.#% /CTOBER #2/7.% 0,!:! (/4%, $5"!)

5!% 4 % ! - 7 / 2 +

& / 2

% 8 # % , , % . 4

$ % . 4 ) 3 4 2 9

(left to right) Dr. Ali Bin Shakar, Director General of MOH, Dr. Ali Al Numairy, the Head of Emirates Medical Association Dr. Aisha Sultan Al Suwaidi the President of the conference and Dr. Jasim Humaid

The 3rd CAD/CAM & Computerized Dentistry International Conference, 2008 proved for the third time that this is an assembly for excellent network. Place where dental professionals - dentists, dental technicians, dental assistants and dental industry can work together, exchange knowledge and ideas and update with the newest technology in dentistry.

Each year CAD/CAM & Computerized Dentistry International Conference gets bigger, and includes participation from more countries. This year the conference attracted more than 450 participants and visitors from 21 countries.

Dr. Aisha Sultan Al Suwaidi, head of Dental Society in Emirates Medical Association and the President of the conference, welcomed the colleagues and motivated them to keep their knowledge continuously updated and improve their skills to insure that they are providing the best care for their patient. Dr. Munir Silwadi, Conference Chairman said: “In its third year, our International CAD/CAM & Computerized Dentistry Conference is setting the standard for highly specialized conferences of our dental profession. With the outstanding success we enjoyed in the previous years our conference is emerging to be the biggest CAD/CAM specialized event in the whole of the Middle East and probably beyond.“ The plenary presentations with internationally-renowned speakers from Germany, South Africa, France, Lichtenstein, Lebanon, and UAE focused on the topics in CAD/CAM in Aesthetic and Prosthetic Dentistry; Computerized Implantology; Computerized Scanning and Imaging; CAD/CAM Dental Laboratories; CAD/CAM Materials; Computerized Management and Planning and Computerized Orthodontics.

Workshops with Ivoclar Vivadent and Nobel Biocare were packed full and covered current topics and trends in the areas.

SIRONA, the Gold sponsor of the conference surprised the delegates with Live-demonstration in the special designed area.

54

3rd CAD/CAM & COMPUTERIZED DENTISTRY INTERNATIONAL CONFERENCE

Dr. Nadim Abou Jaoudeh talking about esthetics in Dentistry

Picture from the audience DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

creartcom.it

The delegates had the opportunity to network with the industry, to see the latest technologies and equipments from: Sirona, KaVo, Nobel Biocare, 3M ESPE, Ivoclar Vivadent, VITA etc.

we have a passion for sterilization Millennium: the safest, complete and most rapid B type sterilizer.

Ideal point of reference in terms of safety, performance and flexibility

via delle azalee, 1 20090 buccinasco (mi) ph. (+39) 0245701505 r.a. - fax (+39) 0248840514 mocomcom@mocom.it - www.mocom.it

NX3.

Nexus Third Generation.

Perfection in permanent cements.

• Simplified delivery. Dual-cure automix syringe eliminates hand mixing.

• Light-cure applications. Cement for veneers and indications requiring unlimited work time.

• Bonds to all substrates. Excellent adhesion to dentin, enamel, CAD/CAM blocks, ceramic, porcelain, resin and metal.

• Self-etch or total-etch. Bonding protocol compatibility. No dual-cure activator required.

OptiBond® All•In•One

One component does it all.

Self-Etch Adhesive System • Simple, one-step process. Etching, priming and bonding are captured in one material. No mixing.

• Exceptional bond strength. Unique nanoetching provides the highest bond strength to both dentine and enamel for seventhgeneration, self-etch adhesives.

• Direct/indirect use. Excellent adhesion to enamel, dentine, porcelain and ceramics – even indirect metal-based restorations when used with Maxcem™ resin cement.

OptiClean™

Innovation for optimal dental care.

Easy and efficient handling: • Faster, easier and complete removal of temporary cement.

• Excellent access thanks to its specific design.

• Clear view of the working surface since no paste or pumice slurry is required.

More gentle than common procedures: • Low risk of abrasion on the preparation and adjacent teeth.

• Gentle to the soft tissue.

• Highly hygienic because it’s single use only.

TempBond

Strong, reliable short-term attachment.

Provisional Cement • Multiple formulations. Original, NE and Clear for all of your provisional needs.

• Delivery choices. Unidose®, tubes and new automix syringe offer flexibility in delivery options.

• Flows and mixes easily. Delivers optimal consistency for solid, complete seating of restorations.

• High bond strength. Heightens patient confidence. Prevents leakage and sensitivity to cold and heat.

KerrHawe SA P.O. Box 268 6934 Bioggio Switzerland Freephone: 00800 41 05 05 05 Fax: ++41 91 610 05 14 www.KerrHawe.com

Your practice is our inspiration.™

Germ free. Fast. Effective.

With the power of free flowing ozone, disinfection becomes fast, easy and more effective than ever. You’ll become your patients’ hero: use Prozone, the new ozone generator from W & H, for disinfection of root canals and periodontal pockets, as well as during cavity preparation and surgical procedures. That’s how you’ll cut the risk of infection. Prozone-power that makes all the difference! wh.com

Ozone power for your patients

Dear Guests

Dear Guests

It gives me great pleasure to welcome you on the 16th Alexandria International Dental Congress. We are proud to see our congress becoming one of the biggest scientific dental events in the Middle East.

This great event was prepared and organized by dedicated staff members, graduates and undergraduates students of the faculty of dentistry, Alexandria University, To whom I express my gratitude and appreciation.

Finally, I would like to welcome you all in Alexandria and wish you a successful congress and pleasant stay.

It is such a great pleasure to welcome you to Alexandria, the city of Alexander the Great.

Alexandria is considered the chief port and the second largest city in Egypt. The organizing committee will take every effort to make the 16th Alexandria International Dental Congress a success.

The problems throughout all the branches of dentistry continue to challenge all of us. The need for multidisciplinary approaches is obvious and difficult to achieve in many occasions. It is our hope that this meeting will intrigue us to share more information as well as to stimulate us in the areas of research and education.

,

Prof. Ahmed Abdella Dean of Faculty of Dentistry, Alexandria University President of AIDC 2008

64

16TH AIDC

,

Prof. Walid El-Kenany Head of Orthodontic Department Faculty of Dentistry, Alexandria University General Secretary of AIDC 2008 DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Prof. Ali Sharaf, Head of the Scientific Committee The opening ceremony

Dr. William Lobel receiving a trophy for his lecture on definitive impression making

Prof. Samir Bechara receiving a trophy from Prof.El Kenany

Pictures from the audience

Dr. Joseph Massad speaking on immediate mandibular implant overdenture DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

Prof. Abdel Salam El Askary talking on flapless implants surgery 16TH AIDC

65

GET YOUR ISSUE ONLINE

www.dentalnews.com

Dr. Mahn receiving a trophy for his lecture on dental composites

Dr. Silber lecturing on Lumineers

Dr. Abdel Rahman Tawfik after his lecture on TMJ Dysfunction Dr. Imad El Hage receiving a trophy after lecturing on Veneers

68

Prof. Thomas Van Dyke discussing inflammation in periodontics

Prof. Sherine EL Attar lecturing on Implantology

Prof. Ahmed Abdella, Prof. Walid El Kenany, Prof. Mary Mehanna

Picture From the closing ceremony dinner

16TH AIDC

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

EXHIBITION FLOOR

70

AIDC 2008

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

72

16TH AIDC

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

PRODUCT REVIEW PRODUCT REVIEW PRODUCT REVIEW

Cavex ColorChange “the best alginate available Cavex produce alginate impression materials for more than 55 years.

As a result all our alginates have been developed to perfection.

Cavex ColorChange This modern dust free alginate has a functional colour indication system and a smooth homogenous consistency. Cavex ColorChange is highly elastic and extremely tear resistant, always resulting in perfect impressions even around strong undercuts. Also this alginate has a 5 day dimensional stability and the impression can always be poured out at least twice.

Dental Advisor rates “excellent” Cavex ColorChange has awarded the highest rating “excellent” by Dental Advisor with an impressing 96% percent score. 71% of the consultants (26 in total) would switch to ColorChange and 76% of the consultants would recommend ColorChange to their colleagues.

For more information www.cavexcentennial.com

Sales of FRC Postec Plus hit the one-million mark Ivoclar Vivadent has sold the root canal post FRC Postec Plus worldwide over a million times. The post, a further development of FRC Postec, is particularly popular on the European and Asian market.

Ivoclar Vivadent's root canal post FRC Postec Plus reached the one-million mark. Overall, one million endodontic posts were sold in a total of 90 countries. In the eyes of the company, this is a milestone.

«Developing FRC Postec Plus from FRC Postec has paid off,» said Thomas Ruhm, Product Manager Endodontics. «The lifelike translucency of the root canal post together with its outstanding radiopacity attracts the interest of customers particularly in Europe and Asia.»

FRC Postec Plus is a highly aesthetic and highly radiopaque root canal post made of glass-fibre reinforced composite. It was developed for the chairside reconstruction of endodontically treated teeth that show extensive coronal damage.

E-Mail: info@ivoclarvivadent.com www.ivoclarvivadent.com

74

PRODUCT REVIEW

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

PRODUCT REVIEW PRODUCT REVIEW PRODUCT REVIEW

Zimmer Dental Launches CopiOs® Pericardium Membrane Zimmer Dental Inc., a leading provider of dental oral rehabilitation products and a subsidiary of Zimmer Holdings, Inc., is pleased to announce the availability of the CopiOs Pericardium Membrane (formerly branded as the Tutodent® Pericardium Membrane) in Europe and Asia. Sourced from bovine pericardial tissue, CopiOs Pericardium Membrane provides the characteristics of natural tissue, coupled with the ease-of-manipulation, conformability, and strength required to meet high clinical expectations and facilitate successful surgical outcomes.

The CopiOs Pericardium Membrane offers tissue compatibility, and is ideal for Guided Bone Regeneration procedures such as block graft coverage and large ridge augmentation where a malleable, drapeable, and durable barrier is desired. Quality is preserved with the unique Tutoplast® process, which thoroughly removes unwanted impurities while maintaining natural tissue qualities and biomechanical stability.

CopiOs Pericardium Membrane is designed to work seamlessly with Zimmer Dental's Puros® family of bone grafting products. As a member of Zimmer Dental's broad portfolio of complementary regenerative membranes, CopiOs Pericardium Membrane is ideal when con-

formability is needed, whereas BioMend® and BioMend Extend™ Membranes are excellent choices in procedures requiring space maintenance.

Under the brand name Tutodent, more than 50,000 of these bovine pericardial membranes have been implanted in patients throughout Europe and Asia since 2000. Zimmer Dental is proud to carry on this tradition with the CopiOs Pericardium Membrane. for more information www.zimmerdental.com

VITA Easyshade® Compact The new generation in digital shade-taking Since its introduction five years ago, the optoelectronic shade measuring unit VITA Easyshade® has convinced dentists and dental technicians through its simple handling and high degree of accuracy in the objective shade determination of natural teeth and dental restorations.

With the arrival of the VITA Easyshade® Compact on the market, the second generation of the measuring device shall now further facilitate the work of dentists and dental technicians in future. At the fairs all over the world, you can now see and test for yourself the VITA Easyshade® Compact.

For the VITA Easyshade® Compact, the established, lightweight and handy form of the previous model was retained. PMT he advanced spectrophotometric technology ensures that unmistakable and accurate results of the determination of natural tooth shades and the shade checking of dental restorations will be displayed within seconds. Other key improvements include its cordless design, which enables the user to move freely, and the modern LED light source. In addition to this, the VITA Easyshade® Compact has sufficient storage capacity for 25 measurements, which also remain stored when the unit is switched off.

76

PRODUCT REVIEW

E-Mail: info@vita-zahnfabrik.com www.vita-zahnfabrik.com

DENTAL NEWS, VOLUME XV, NUMBER IV, 2008

PRODUCT REVIEW PRODUCT REVIEW PRODUCT REVIEW Sensodyne launches world’s first toothpaste to combat threat of acid erosion to children’s teeth Sensodyne from GlaxoSmithKline (GSK) has launched into the Middle East the world's first toothpaste specifically designed to tackle the problem of children's acid erosion.

The PRONAMEL for Children is low in abrasivity and pH neutral to help reduce enamel wear during the process of tooth brushing.

Moreover, the optimised fluoride formulation helps re-harden children's enamel and the mild mint taste is developed to keep them feeling refreshed.

Acid erosion is caused by a combination of factors including the increased acidity in the modern healthy diet and abrasive tooth brushing. In an effort to maintain a healthy diet for their children, mothers encourage their children to consume more nutritious foods and drinks. Acid found in many of these healthy fruits and fruit juices can cause the softening of the teeth's enamel surface making the enamel prone to wear. Almost everybody with natural teeth may develop some signs of acid erosion, which can affect all age groups.

The effects, which can visibly affect the tooth's appearance, cannot be reversed, but can be reduced.

“GSK formulated the Sensodyne PRONAMEL for Children toothpaste

to help protect children's teeth against acid erosion. Using Sensodyne PRONAMEL for Children allows children to enjoy a healthy and a varied diet while still protecting their teeth from the effects of acid erosion. The toothpaste has a high fluoride uptake to harden the enamel surface, helping it to resist further acid attack, in addition to all the benefits of a regular toothpaste - fluoride to fight cavities, freshens breath and cleans teeth,” said Wally.

The launch of PRONAMEL for Children is being supported by a consumer marketing campaign to make the public at large aware of this issue, and consumers are being encouraged to regulate their children's visits to their dentist with any concerns. www.golinharris.com