1 3 2
TABLE OF CONTENTS
WHAT TO LOOK FOR
The global diagnosis of tooth wear 1
HOW TO DO
HOW TO START
Functional and esthetic stabilitation of the patient 175
The initial consultation efficient and persuasive
119
XVI
4 5
TABLE OF CONTENTS
HOW TO PLAN 359
A DIGITAL 3STEP
The completion of the full-mouth rehabilitation
WHAT NEXT
421
XVII
TABLE OF CONTENTS
TABLE OF CONTENTS Who I am V Foreword by Mirela Feraru VI Foreword by Ignazio Loi VII Introduction X If you wonder why… XIV In this book... XV
CHAPTER 1
WHAT TO LOOK FOR The global diagnosis of tooth wear
1
DENTAL EROSION
17
The patients’ perspective The dentist’s perspective
20 21
Etiology of dental erosion Anterior teeth under the erosive attack Posterior teeth under the erosive attack
18
22 26 30
ANTERIOR CLINICAL EROSIVE (ACE) CLASSIFICATION 35 Ace Class I Ace Class II Ace Class III Ace Class IV Ace Class V Ace Class VI Anterior Upgrade
XVIII
Risk of functional conflicts Evolution of anterior conflicts
Explosive signs Implosive signs Initial signs of a dangerous evolution
93 96
98 99 100
The Gtest 102
DENTAL WEAR AND AGEING 3 Erosion 6 Functional wear 6 Dental ageing 8 Physiologic mechanism involved in dental ageing 10 Modern humans: the hypostimulation 16 Signs of dental erosion
CHEWING PATTERNS AND Gtest 87 Horizontal chewing pattern 90 Vertical chewing pattern 92
38 40 42 46 48 50 52
ANTERIOR FUNCTIONAL CONFLICTS (AFC) Dental signs of AFC Displacement Wear Damage location of AFC
53 62 63 64 70
NOBRUX CLASSIFICATION Static conflicts 1. Skeletal discrepancy 2. Dental discrepancy 3. Loss of posterior support 4. Ageing Dynamic conflicts 1. The third object 2. Sitting on the wall 3. Horizontal chewing 4. Idiopathic bruxism
71 74 76 76 77 78 80 82 83 85 86
Anterior Garage: analysis of the cycle out 103 TOOTH WEAR THERAPY YES OR NO?
107
Thick and flat patients Thin and rough patients
110 113
Therapy of erosion Therapy of dysfunctional wear
108 110
119
OBSERVING 121 3STEP Awareness
122
Which is the perfect 3STEP initial consultation? Length of the first consultation
125 125
Quick mock-up
126
LEVEL 1 The esthetic evaluation
LEVEL 2 The reconstructive needs LEVEL 3+ The functional analysis
126 128 130
Planas test 130 Gtest 131 Masticatory muscle activation 132 Pinky test 132 Neck test 132
Initial records for the laboratory
134
Impressions 135 Face bow 135 Bite registration 135 How to articulate the mandible? 136 Posterior wax record 140 CAPTURING 143 Face and Smile 144 Frontal Smile 146
The 3 Superior Lines
Extra photos
Soft tissue potential lesions Lingual aspect of the anterior teeth Gingival focus Parafunctional habits Condition of the occlusal guards
148
3/4 Smile with open mouth 152 Profile 155 Maxi Stretch 156 Frontal MIP 157 Open 158 Mandible 159 Under the Bite 160 2 Planas 161 Protrusive 162
170
171 172 172 173 173
CHAPTER 3
HOW TO DO Functional and esthetic stabilization of the patient
175
THE 3STEP TECHNIQUE
177
Lab STEP 1 Analysis of the initial models Position control The Anterior Stop The Posterior Stop External wax up Clin STEP 1 The mock-up visit External wax up control Mock-up key control Teeth control What to evaluate when the mock-up is in the mouth 1. Maxiline, central axes, and Cross 2. Esthetic Lines 3. Vestibular harmony 4. Tooth colour 5. Location of the margins 6. Type of final restorations 7. Mandiline Anterior JIG and bite registration To remove or not remove the mock-up? Transfer information to the laboratory STEP 2 - The posterior support
184 185 186 188 198 200 206 210 212 213
3STEP WORKFLOW STEP 1 - The esthetic analysis
CHAPTER 2
HOW TO START The initial consultation – persuasive and efficient
4 Posterior 164 Premaxilla 166 Maxi O 168 Mandi O 169
Lab STEP 2
180 183
216 216 217 218 218 219 219 220 222 225 226 229
230
Why do not include the second molars in the Posterior wax up? 231 How to distribute the posterior spaces? 232 1. Frontal alignment 234 2. Mandibular shape 235
The 3 Inferior Lines
3. Posterior Garages The External Garages Too closed Too open The Internal Garages Too close Too open The 4 Garage Mistakes
236
242 243 244 245 247 248 249 250
Clin STEP 2 The White Bite 256 Which type of White Bite? 260 1. Thickness of the final restorations 262 2. Final dental material choice 262 3. Budget 263 4. Length of the appointment 263 5. Underlying substratum 264 Provisional White Bite 266 Final White Bite 269 Direct White Bite 270 1. Posterior wax up 272 2. Transparent key fabrication 276 3. Clinical handling of the transparent keys 278 How to do occlusal adjustments with the White Bite? 284 Restore or not the anterior open bite? 288 1. Phonetic impairment 289 2. Extremely worn-down dentition in explosive patients 289
CONTROL VISIT
THE FOLLOW-UP 291 1. Occlusal adjustments 293 Centering the mandible 294 Distribution of the posterior contacts 295 Freedom 296 Chewing 297 2. Shade selection 297 3. Restoration of the mandibular anterior teeth 298 4. Preparation of the maxillary anterior teeth 300 5. Maxillary final impression 304 6. Mandibular alginate impression 305 7. Anterior bite record 305 8. Face bow 305 STEP 3 The Anterior Adhesive Additive Restorations (A3Rs) 307 Objectives and associated A3Rs 310 F and A objectives: the facial esthetic 312 Intact facial surfaces 313 Damaged facial surfaces 316 B point: the increase of VDO and Anterior Contact 317 C objective: the palatal damage 318 LAB STEP 3 Fabrication of the A3Rs 1. Incisal hook 2. Vestibular overlap: the additive chamfer 3. A point: the esthetic length
328 332 333
and the incisal embrasures 4. A edge: the incisal edge to incise 5. AB area: out of the way and the canine spaces 6. B point: the contact point 7. MD interproximal contacts: the marginal crests 8. BC area: the MD bevelled crests and the pistorius style 9. C point: the cervical palatal limits 10. Palatal surface: the useless anatomy and texture Clin STEP 3 - Bonding A3Rs
1. Esthetic try-in 2. Stability control 3. Interproximal and cervical fitting 4. Bonding procedures A3R procedures Tooth Procedures 5. Occlusal adjustements Clinical case
CHAPTER 4
HOW TO PLAN A DIGITAL 3STEP
335 336 337 338 339 340 342 343 346
348 352 353 357 357 358 361 364
Internal Mandible Posterior
407 407 408
A3Rs project Sagittal cut Frontal Under the Bite
412 412 413 413
Direct white bite
CHAPTER 5
WHAT NEXT The completion of the full-mouth rehabilitation 415 AFTER THE PROVISIONAL 3STEP Final 3STEP requirements Provisional 3STEP characteristics Anterior Upgrade
Anterior Upgrade planned from the beginning Anterior Upgrade in case of esthetic failure of the A3Rs
Posterior Upgrade
367
THE 3STEP CONTROL ON THE DIGITAL WORKFLOW 369 Digital - Love and hate 370 Initial study and position control 373 Face and Smile 377 Lateral face 378 Frontal 379 Under the Bite 380 External 381 Mandible 382 4 Posterior 383 Anterior Stop and the Increase of VDO 384 Sagittal cut 385 Palatal view 386 Internal 388 External wax up before printing the models 390 Face and Smile 392 Frontal 393 Under the Bite 395 External 396 Mandible 397 Maxi Control 398 Posterior wax up and the type of White Bite 400 4 Garage mistakes 403 Frontal 405 Under the Bite 405 External 406
409
Presence of caries Need to replace existing failing restorations Final posterior support in ceramic Direct posterior upgrade
Sequence of the Upgrades
Anterior to Posterior Posterior to Anterior Bite, yes or not? Clinical cases
417 418 419
420
422 423
426
428 430 433 434
438
438 438 440 442
FOLLOW THE FINGER 448 EVOLUTION 456
THE CARDS
Clinical, Laboratory, Digital
459
Initial Consultation 460 Initial Lab 462 Anterior Stop 463 External wax up 464 External mock-up 465 Posterior wax up 466 Control visit 467 A3Rs 468 Initial Lab 469 Anterior Stop 470 External wax up 471 Posterior wax up 472 A3Rs 474 3STEP CODE 475
You can access the videos via QR code or by registering on the site https://3step-additiveprosthodontics.edrapublishing.com/ XIX
STEP 1 THE ESTHETIC ANALYSIS
STEP 1 THE ESTHETIC ANALYSIS
In the last decade, Dentistry has shifted the attention towards Esthetic greatly. Computer software have been developed to visualize the new smile already during the first consultation, and thanks to these marketing tools more costumers are ready to accept esthetic improvements at the level of their teeth. There are no doubts about the psychological contributions of these interventions to the patient’s quality of life. However, questions arise when the treatments not only require the removal of healthy tooth structure (Subtractive, invasive Dentistry), but also impair the function of the patients. In general, it could be stated that all the esthetic interventions which lengthened and thickened the incisal edges may potentially create functional conflicts, especially if they are not associated to an increase of VDO to guarantee the presence of a functional space. Basing the smile re-looking only on standard esthetic rules, which will not consider each patient unique, can be also very risky for the longevity of the planned esthetic restorations. To correctly plan a new smile, energy should be invested in studying the specific situation (stop and think). Consequently, instead of spending time during the first consultation, proposing esthetic shape of the teeth which are not functionally suitable for the patients, the 3STEP technique prefers to postpone the information on the esthetic outcome of the treatment after the initial data are elaborated (analysis of the articulated models). At the conclusion of the initial consultation, where the attention must be focused mostly on the diagnosis of the problem (e.g. incisal edge wear) the patient is informed that if he/she can know more about the most appropriate dental treatment, an esthetic mock-up visit can be scheduled. This will give the time for the lab tech and clinician to analyze which esthetic rehabilitation that patient can afford. 183
3 | HOW TO DO: FUNCTIONAL AND ESTHETIC STABILITATION OF THE PATIENT
With a good impression, a good wax up, a good mock-up key and a correct placement in the mouth, the excess will be minimal and they can be gently removed with a scalpel.
If the surface of the mock-up appears artificial due to the monochromatic colour and the blocked contact points, external colourants, such as violet, mixed with adhesive bond can be used to create a more natural look 17 . If major modifications of the mock-up are required, first photos of it must be taken, to give an opportunity for the lab tech to see his/her work in the mouth, before it is changed.
MINIMAL
While injecting the material in the key, attention should be placed to keep the tip of the gun in the deepest part of the key (incisal edges location) to avoid the presence of air bubbles. Little defects can be repaired with flowable composite. Major ones will represent a waste of clinical time with a questionable esthetic outcome, since the reconstruction of the incisal edges by hand requires good skills and time 16 .
MAJOR
16
Minimal additive repairs can be done using flowable composite. Major defects should be avoided by correctly positioning the tip of the gun at the bottom of the incisal edges while injecting the material in the key.
214
THE 3STEP TECHNIQUE
INITIAL STATUS 17
NOT COLOURED
COLOURED
The shade of the mock-up should be decided with the patient. It is better to select a brighter colour, which could be darken with colorants in case patient is not happy with brighter teeth, like in this patient.
A mock-up is an excellent tool to explain patients shape, color and thickness of the future restorations. Partially remove it while the patient observes the procedure with a hand mirror allows to explain thickness and length added.
215
STEP 2 THE POSTERIOR SUPPORT
The step 2 is the heart of the 3STEP technique. It consists in the progression of the wax up to the posterior teeth, after an increase of VDO has been set for each patient. The laboratory project is then transferred in the mouth, by means of additive restorations called the White Bite. The increase of VDO is what has made the 3STEP the most controversial therapy back in 2006 when for the first time the clinical outcome of the first 4 patients treated following its protocol were presented in a conference to the dental community. Until then, there was not a protocol for full-mouth rehabilitations which was always implementing an increase of VDO. On the contrary several Author were warning about the risks of this approach. After more than 15 years and hundreds of patients treated with an increase of VDO, the White Bite at the increased VDO can be considered an excellent alternative to healthy tooth structure removal (Subtractive Dentistry). These some of the advantages of planning a full-mouth rehabilitation at an increased VDO: • Additive restorations are potentially reversible • Not invasive rehabilitation is more accepted by patients • It can compensate loss of posterior support and VDO • It can allow for “human testing” in modifying the mandible’s position in dysfunctional patients. 229
©Quintessence Publishing
WHICH TYPE OF WHITE BITE?
For each patient, the clinician and lab tech must determine which types of White Bite should be more appropriate. A White Bite can be provisional or final. When the White Bite is meant to be final, the clinician must be sure that there are not failing restorations or caries left under it and that the interproximal contacts points are correct. In case of provisional White Bite, it is meant to be replaced by the final restorations after the completion of the 3STEP and the functional test-drive. In this case the substratum is less important as well as the quality of the interproximal contact points, since it is an additive interim. The replacement of the White Bite is called the Posterior Upgrade.
260
Based on the type of reconstruction, a White Bite can be direct or indirect. A direct White Bite consists of composite restorations done directly in the mouth by means of transparent keys. If the restorations are fabricated outside the mouth and after bonded, the White Bite is called Indirect. In the initial cases treated following the 3STEP protocol, the dentitions were so compromised that the White Bites were always meant to be provisional, and replaced with the final restorations. Consequently, the non-opened interproximal contact points were not a real problem, and the fast fabrication was a clinical advantage to start the occlusal adjustments without investing too much time in the reconstruction of so many posterior teeth.
©Quintessence Publishing
Nowadays, the interception of patients at an early stage of dental wear, and the request to lower the budget for full-mouth rehabilitation (eliminating the Posterior Upgrades), is forcing clinicians to find alternative approaches. In this optic, the direct technique to fabricate the White Bite explained in this chapter, has been improved to promote, whenever possible, a self-opening interproximal contact. In case of healthy substratum, and less budget restrictions the White Bite can be composed by final restorations, prepared in the laboratory and bonded individually, (indirect White Bite). For each patient, the clinician should take the time to analyse the different parameters and select the most appropriate White Bite.
There could be 4 major types of White Bites: 1. DIRECT PROVISIONAL 2. INDIRECT PROVISIONAL 3. DIRECT FINAL 4. INDIRECT FINAL There are 5 points to consider when selecting the type of White Bite: 1. THICKNESS OF THE FINAL RESTORATIONS 2. FINAL DENTAL MATERIAL CHOICE 3. BUDGET 4. LENGTH OF THE APPOINTMENT 5. UNDERLYING SUBSTRATUM
261
3 | HOW TO DO: FUNCTIONAL AND ESTHETIC STABILITATION OF THE PATIENT
HOW TO DO OCCLUSAL ADJUSTMENTS WITH THE WHITE BITE?
1 284
To facilitate the task, especially for clinicians not familiar with full-mouth occlusal adjustments, the 3STEP establishes the posterior support without the anterior contacts. The clinician will start even with the reconstruction of a reduced number of posterior teeth, 2nd molars excluded so that a reduced number of occlusal contacts is necessary. There are 4 levels of occlusal adjustments which should be performed in a specific progressive order, from the easiest to the most difficult, from static to dynamic adjustments: 1. CENTERING THE MANDIBLE 2. DISTRIBUTE THE POSTERIOR CONTACTS 3. FREEDOM 4. CHEWING
It will depend on the clinician how thorough these adjustments will be done during the clin step 2. The initial goal after the reconstruction of the posterior occlusal surfaces is to have the elevator muscles equally contracted, while they guide the mandible to a centered position without any deflective tooth contacts. Since the anterior contacts are missing, clinicians should pay attention mostly to the lateral deflective contacts (left or right posterior deflection). The absence of the 2 molars also reduce the possibility of posterior deflective contacts. First objective after the deliver of the White Bite is to eliminate deflective contacts, this is called centering the mandible. The patient is asked to close the jaw gently to identify possible deflective contacts and remove them, before the mandible slides.
CENTERING THE MANDIBLE
DISTRIBUITE THE POSTERIOR CONTACTS
2
STEP 2 - THE POSTERIOR SUPPORT
A fast posterior deprogramming method can be used, the COTTON SIT. Two cotton rolls are placed on the White Bite while the patient opens and closes very fast, tapping on the cotton rolls. While he/she is doing this, the focus will be on the alignment of the mandible disturbed or not by the rolling of the rolls back and forward on the posterior support. If the mandible maintains the same pattern of opening/closing, the cotton rolls are removed and the first contact on the White Bite identified. If the patient feels contact only on one side, and to achieve bilateral contacts he/she has to slide, it is then important firstly to verify the frontal alignment of the mandible in the project (e.g. the final mandibular mounting in the articulator). Then, the goal is to eliminate any lateral deviations. Until there are deflective contacts and the mandible slides, laterally only one articulator paper should be placed in the mouth to mark the first contacts before the deviation. Contacts obtained contralateral-
ly after the mandible slides, should be ignored. Alternating the Cotton Sit to the unilateral very thick (100 micron) articulator paper, the VDO is reduced on the side of the initial contacts until contact points also appear on the other side of the mouth and the mandible stops sliding. A mandible is centered when there are no deflective contacts (no slide while closing in MIP). The next level in the static occlusal adjustments deals with the distribution of the posterior contacts. Clinician must obtain one contact point of equal intensity for each posterior tooth involved in the White Bite. This will provide a sense of stability even though the number of teeth in contact is reduced compared to MIP (no anymore contacts on the anterior teeth and on the second molars). To achieve the distribution of the contacts, two heavy thickness articulator papers are placed at the same time on both sides and the patient is invited to bite on them very fast without thinking. The Cotton Sit can still be used to depro-
FREEDOM
CHEWING
3
4 V48 Gtest BEFORE THE WHITE BITE V49 Gtest AFTER THE 3STEP
285
CONTROL VISIT THE FOLLOW-UP
The Control visit is the visit where the clinician meets the patient again after delivering of the White Bite. While the mock-up visit can be scheduled independently from the rest of the therapy, the White Bite, the Control visit and the bonding of the anterior restorations must be planned together. Following an ideal 3STEP schedule, the Control visit is planned after 1 week from the White Bite, and the delivery of the Anterior Adhesive Additive Restorations (A3Rs) generally takes another week to allow the lab tech to fabricate the restorations and the patient to keep adapting to the modified occlusion. The first week time before the Control visit is necessary to test the new posterior support so that the patient can better distinguish between a normal functional adaptation problems (that in one week improve by themselves) and not correct occlusion problems (which persist and/ or become worse). If the Control visit is scheduled too early after the delivery of the White Bite, patients may demand excessive modifications because of insufficient time of integration. On the other hand, waiting too long, and leaving the patient with an anterior open bite, is not recommended, especially in case of vertical wear and the tendency of the patient to be Implosive and a clencher. For the elevated risk of anterior teeth supraeruption and loss of the planned anterior restorative space, the anterior contact points must be restored in a short time (max 2 weeks). There are a few exceptions, such as in case of intact anterior teeth, where the clinician may plan to wait on purpose to see if the anterior open bite resolves by itself. 291
STEP 3
THE ANTERIOR ADHESIVE ADDITIVE RESTORATIONS (A3Rs)
After the delivering of the White Bite, an anterior open bite is created, providing the space to restore the anterior maxillary teeth in an additive manner, as an alternative to crowns. There are 3 types of Anterior Adhesive Additive Restorations (A3Rs) delivered during the 3STEP: PALATAL VENEER: a (CAD/CAM monolithic) composite restoration, which mostly addresses the palatal damage and the worn-down incisal edges. The facial limit of this veneer is positioned on the vestibular surface with an overlap (additive chamfer), which could be blended by adding a direct composite or by just polishing the step. TACO: a (CAD/CAM monolithic) composite restoration, which reconstructs the palatal and the vestibular surfaces at the same time. It has a V shape because the interproximal contact points of the teeth are left intact. STEP VENEER: this restoration is a modified facial veneer which presents a step at the level of its palatal margin. During the bonding procedure, the step will guide the delivery of an additional direct composite restoration, to obtain a thicker palatal aspect. This restoration can be fabricated both in ceramic or in CAD/CAM composite. 307
3 | HOW TO DO: FUNCTIONAL AND ESTHETIC STABILITATION OF THE PATIENT
Already with the External wax up, and the Anterior Stop, clinicians had the opportunity to evaluate the shape of the final A3Rs at the level of the two central incisors. During the step 3, after the delivering of the White Bite, the shape of the A3Rs of all the 6 maxillary anterior teeth should be finalized. As for the Anterior Stop, the lab tech should start waxing up only the 2 central incisors, to reconstruct the Anterior Garage following the esthetic guidelines validated with the mock-up visit. Ideally the proposed shape for the 2 central incisors points should
TACO
F
F LOCATION • Incisal • Middle
be adapted to the new models and validated by the clinician, before completing the wax up of the other anterior teeth. Differently from the Anterior Stop, this time however, the VDO is set by the presence of the White Bite. If major discrepancies in the VDO are detected the lab tech should still fabricate the palatal shape based on the validated Anterior Stop. The White Bite can be clinically modified accordingly (subtractive modifications in case of excessive VDO increase, or additive modifications in case of not enough increase).
C
• Cervical
MINI TACO
THICKNESS • Change color
• Structural damage • Pistorius extension
• Good initial color
FACIAL INCLINATION
PALATAL VENEER
DIASTEMA CLOSURE?
B TO CLOSE ANTERIOR GARAGE B to be bulked?
TO OPEN ANTERIOR GARAGE 308
A
A to be flared?
STEP 3 THE ANTERIOR ADHESIVE ADDITIVE RESTORATIONS (A3Rs)
ACHIEVE OR NOT THE A3Rs OBJECTIVES
OBJECTIVES
To stop before 1/3 middle 1/3 incisal
OBJECTIVES
To length the initial incisal edge
To keep the existing length of the clinical crown
OBJECTIVES
To achieve anterior contact point after the increase of VDO
To leave an anterior open bite
OBJECTIVES
F A B C
To restore the facial aspect up to the cervical margins
To restore the palatal aspect to the cervical margins
To stop before 1/3 middle 1/3 incisal
309
3 | HOW TO DO: FUNCTIONAL AND ESTHETIC STABILITATION OF THE PATIENT
As already mentioned, patients treated with the 3STEP technique most often require modification of the incisal edges to functionally integrate the restorations in time. The reconstruction of the A point will make the Anterior Garage door longer and thicker, and the clinician must be very careful not to generate anterior conflicts. In case the patient is a Horizontal chewer with an Explosive evolution (see Chapter 1, page 96), the risk of developing anterior conflicts is very high, since their muscular nature will promote an edge-to-edge position with ageing. To contrast their natural tooth ageing, multiple increases of VDO during the patient life should be planned (VDO Upgrades) to go against their muscular nature and keep open the Anterior Garage. For this group of patients, the choice of the dental material is very critical, and the literature is not conclusive on this specific topic. The final choice is left to each clinician’s decision. This could be defined the choice of the weak link. Is it better to place the weak link at the level of the restored incisal edges, using a weaker material such as
composite to save the antagonistic teeth, or is it preferable to restore the incisal edges with stronger material, such as ceramic which will not be then the weak link in case anterior conflicts development? The new weak link could be the periodontal tissues (occlusal trauma) or the antagonist incisal edges (see Chapter 1, page 56). In the Author’s opinion, if a strict functional monitoring to detect the anterior conflicts, associated with the VDO Upgrades are not possible, it is wiser to use CAD/CAM monolithic composites, since they represent more adaptable material, self-adjustable by the patient and by the clinician during the follow ups. In the Author’s experience ceramic Palatal veneers are not a good choice for the more difficult capacity to blend the facial surfaces with a vestibular overlap. In addition, especially in an erosive environment, ceramic can be very aggressive toward the antagonistic teeth 51 . The ceramic may be proposed for the Step veneers and for the Double veneers, but for each patient, a careful evaluation of the pros e cons of the dental material choice should be carried out.
51
Ceramic Palatal veneers are not recommended for their aggressive nature toward the antagonistic teeth especially in an erosive environment. CAD/CAM monolithic composites would have been the better choice. In this patient, in fact the ceramic Palatal veneers aged perfectly but the antagonistic tooth presents an accelerated wear. 322
STEP 3 THE ANTERIOR ADHESIVE ADDITIVE RESTORATIONS (A3Rs)
52
CAD/CAM composite monolithic Tacos. These A3Rs were very difficult to be made due to the very limited thickness and difficult to bond for the blending of the interproximal margins. An easier, but less esthetic choice, could have been Palatal veneers.
Finally, the decision on the more appropriate A3Rs should be based also on the clinician’s bonding skills. Tacos are the most difficult restorations to be delivered correctly, since the clinician must take care of a very long margin, starting for the palatal location that is always difficult with high risk of moist contamination and poor visual access. Tacos represent an additional complexity to blend the mesial and distal interproximal surfaces, which present closed contact points 52 . The Step veneers are easier compared to the
Palatal veneers and the Tacos, but they may require a little more attention, since once bonded, the clinician must smooth their palatal step with the palatal unrestored surface, with a direct composite restoration. In the end, the lab support is essential, as in every indirect restoration, and lab tech are not trained to fabricate A3Rs as they are for crowns and facial veneers. In the following section, laboratory parameters will be described helping clinicians and lab techs to improve the quality of the fabrication of the A3Rs.
323
3 | HOW TO DO: FUNCTIONAL AND ESTHETIC STABILIZATION OF THE PATIENT
CLINICAL CASE 67-year-old male Explosive patient affected by severe erosive wear (ACE Class VI). • Indirect final White Bite with CAD/CAM monolithic composite onlays and provisional restorations on the implants. • Direct composite build up on the anterior teeth without post and core and no tooth preparation. • CAD/CAM monolithic composite Tacos (maxilla) and Facial veneers (mandible). • CAD/CAM monolithic composite Maryland bridge cantilevered from left canine.
364
STEP 3 THE ADDITIVE ANTERIOR ADHESIVE RESTORATIONS (A3Rs)
STEP 1
STEP 2
STEP 3
EXTERNAL MOCK-UP
WHITE BITE
A3Rs
ANTERIOR DEPROGRAMMING
FINAL INDIRECT
TACOS + MARYLAND BRIDGE 365
