Diagnosis of vertical root fractures in endodontically treated teeth based on clinical and radiograp

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Diagnosis of Vertical Root Fractures in Endodontically Treated Teeth Based on Clinical and Radiographic Indices: A Systematic Review Article in Journal of endodontics · September 2010 DOI: 10.1016/j.joen.2010.05.003 · Source: PubMed

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Clinical Research

Diagnosis of Vertical Root Fractures in Endodontically Treated Teeth Based on Clinical and Radiographic Indices: A Systematic Review Igor Tsesis, DMD,* Eyal Rosen, DMD,* Aviad Tamse, DMD,* Silvio Taschieri, MD, DDS,† and Anda Kfir, DMD* Abstract Introduction: The diagnosis of vertical root fracture (VRF) is at times complicated for lack of specific signs, symptoms, and/or radiographic features. The purpose of this study was to systematically search and evaluate the literature regarding the diagnostic accuracy of clinical signs and symptoms and radiographic indices for the diagnosis of VRF in endodontically treated teeth by means of a systematic review. Methods: An exhaustive literature search combined with strict inclusion and exclusion criteria was undertaken to identify clinical studies that assessed the diagnosis of VRF. Results: There is no substantial evidence regarding the accuracy of the clinical and radiographic indices for the diagnosis of VRF in endodontically treated teeth. Conclusions: Evidence-based data concerning the diagnostic accuracy and clinical effectiveness of clinical and radiographic dental evaluation for the diagnosis of VRF in endodontically treated teeth are lacking. The need for evidence-based research efforts to elucidate the currently unknown situation is of utmost significance.

(J Endod 2010;36:1455–1458)

Key Words Diagnosis, systematic review, vertical root fracture

V

ertical root fracture (VRF) in endodontically treated teeth is one of the most frustrating complications of root canal therapy, which results in the tooth or root extraction (1–4). The VRF is a longitudinally oriented fracture of the root that originates from its apical end and propagates coronally (5) and is defined as one of the crack types (5).

The incidence of vertically fractured teeth has not been described in the literature.

However, the prevalence was reported to range from 11%–20% of VRFs in extracted endodontically treated teeth (6, 7).

VRF is usually diagnosed years after all endodontic and prosthetic procedures have been completed (8). The final diagnosis of VRF is at times complicated for lack of specific signs, symptoms, and/or radiographic features and because several etiologic factors might be involved. Thus, the differential diagnosis from other pathologic entities might be difficult (3, 8–14).

Evidence-based dentistry is an approach to oral healthcare that integrates the best available clinical evidence to support a practitioner’s clinical expertise for each patient’s treatment needs and preferences (15–17). It is based on the process of systematically finding, apprising, and using research findings as the basis for clinical decision-making.

Systematic reviews constitute the basis for practicing evidence-based dentistry (15, 17, 18). The application of evidence-based dentistry in diagnosis should result in a reduction of errors in the clinical decision-making process (15–18). Thus, evidence-based review of the available literature regarding the clinical and radiographic features of endodontically treated vertically root fractured teeth is of utmost importance (2, 4).

The aim of this study was to systematically search and evaluate the literature regarding the diagnostic accuracy of clinical signs and symptoms and radiographic indices for the diagnosis of VRF in endodontically treated teeth by means of a systematic review.

Materials and Methods From the *Department of Endodontology, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel; and †IRCCS Istituto Ortopedico Galeazzi, Department of Odontology, University of Milan, Milan, Italy.

Address requests for reprints to Dr Igor Tsesis, Department of Endodontology, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel.

E-mail address: dr.tsesis@gmail.com.

0099-2399/$0 - see front matter Copyright ª 2010 American Association of Endodontists. doi:10.1016/j.joen.2010.05.003

Criteria for Considering Studies for This Review This systematic review included clinical studies that assessed the diagnosis of VRF consistent with the following definition: complete or incomplete fracture initiated from the root at any level (5). Case reports, reviews, in vitro studies, and studies of teeth with vital pulps were not included in the review.

The studies had to include patients with confirmed VRFs (target condition) in endodontically treated teeth. Studies with at least one of the following reference standards for VRF confirmation were included (reference standard defined as the best available method for establishing the presence or absence of the target condition (19)). The VRFs were confirmed during surgical flap procedure, the VRFs were confirmed after tooth extraction, or the VRFs were identified radiographically as clearly discernable separation of segments of fractured roots.

The studies had to include detailed data regarding the clinical signs and symptoms and the radiographic findings of the evaluated teeth. Table 1 summarizes the criteria for inclusion of studies in the systematic review.

Search Methods for Identification of Studies The following electronic databases were searched. MEDLINE database was searched by using Evidents web-based search engine (http://medinformatics.uthscsa.

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Clinical Research TABLE 1. Criteria for Inclusion of Studies in the Systematic Review 1. Clinical studies that assessed the diagnosis of VRF. 2. VRF definition corresponded with the description of complete or incomplete fracture initiated from the root at any level.

3. Only endodontically treated teeth were included.

4. VRF confirmation method was in accordance with the defined reference standards.

5. Detailed data were included regarding the clinical signs and symptoms and radiographic findings of the evaluated teeth.

VRF, vertical root fractures.

edu/EviDents/), by using the key words ‘‘vertical root fracture OR ‘‘longitudinal root fracture’’, and applying Entrez PubMed limits to ‘‘humans’’ and ‘‘English’’. MeSH received the following: (vertical[All Fields] AND (‘‘plant roots’’[MeSH Terms] OR (‘‘plant’’[All Fields] AND ‘‘roots’’[All Fields]) OR ‘‘plant roots’’[All Fields] OR ‘‘root’’[All Fields]) AND (‘‘fractures, bone’’[MeSH Terms] OR (‘‘fractures’’[All Fields] AND ‘‘bone’’[All Fields]) OR ‘‘bone fractures’’[All Fields] OR ‘‘fracture’’[All Fields])) OR (longitudinal[All Fields] AND (‘‘plant roots’’[MeSH Terms] OR (‘‘plant’’[All Fields] AND ‘‘roots’’[All Fields]) OR ‘‘plant roots’’[All Fields] OR ‘‘root’’[All Fields]) AND (‘‘fractures, bone’’[MeSH Terms] OR (‘‘fractures’’[All Fields] AND ‘‘bone’’[All Fields]) OR ‘‘bone fractures’’[All Fields] OR ‘‘fracture’’[All Fields])) NOT (‘‘animals’’[MeSH:noexp] NOT ‘‘humans’’[MeSH Terms]) AND (‘‘humans’’[MeSH Terms] AND English[lang]). Scopus search (www. scopus.com) was searched by using the key words ‘‘vertical root fracture’’ OR ‘‘longitudinal root fracture’’, by using these filters: articles, limited to dentistry, English language. Query received the following: TITLE-ABS-KEY(‘‘vertical root fracture’’ OR ‘‘longitudinal root fracture’’) AND (LIMIT-TO(DOCTYPE, ‘‘ar’’)) AND (LIMIT-TO(SUBJAREA, ‘‘DENT’’) OR LIMIT-TO(SUBJAREA, ‘‘MULT’’)) AND (LIMIT-TO(LANGUAGE, ‘‘English’’)). Embase database (http://www.embase.com) was searched by using the key words ‘‘vertical root fracture’’ OR ‘‘longitudinal root fracture’’, with these limits: humans, English, article, Embase only.

MeSH received the following: (’vertical root fracture’ OR ’longitudinal root fracture’) AND [article]/lim AND [humans]/lim AND [english]/ lim AND [embase]/lim.

Related articles, literature reviews that appeared in the MEDLINE search engine, and textbook chapters were evaluated, and their reference lists were manually checked.

Data Collection and Analysis Selection of Studies. The articles were initially evaluated for relevance, on the basis of their titles and abstracts, by 3 observers independently (I.T., A.T., E.R.). Possibly relevant studies were submitted to a full text evaluation. The full texts of the studies were obtained and reviewed for suitability. Cases of disagreement were discussed together until agreement was achieved. Eventually, the identified suitable articles were subjected to data extraction, assessment of the methodological quality, and data analysis.

Data Extraction. Data were to be extracted by 3 observers independently. Cases of disagreement were to be subject to joint evaluation by the observers until an agreement was achieved.

For each study the following methodological parameters were to be recorded: authors and date of publication; study’s purpose; sample size; demographic details of the subjects including criteria for inclusion; study design; reference standard type; evaluation methods including the presence of multiple evaluators, calibration of evaluators, randomization, and evaluators’ blinding; homogeneity of the subjects; statistical analysis type and quality; and funding source.

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The following index tests, defined as tests performed to reduce the uncertainty about the presence of the target condition (19, 20), were to be recorded: tenderness to percussion and/or palpation, presence of a sinus tract, pain, swelling, presence of periradicular radiolucency, presence of an osseous defect/periodontal pocket, gender and age of the patient, tooth type, coronal restoration type, and presence of post.

Methodological Quality Assessment and Data Synthesis and Analysis. On the basis of the study methodological parameters, an assessment of the methodological quality of the included studies was planned to be undertaken following the recommendations of the guest editorial on evidence-based dentistry published by the Journal of Endodontics in 2009 (15) and the recommendations of ‘‘The Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy’’ (20).

The diagnostic accuracy was planned to be calculated by comparing the results of the index tests with the outcomes of the reference standards (16, 19, 21).

Results The search in MEDLINE database by using Evidents web-based search engine covered all articles published in dental journals in English from 1971–January 2010 and resulted in 197 articles, of which 19 were eligible for inclusion (3, 10, 14, 22–37) on the basis of their titles and abstracts. The other 178 articles were rejected; 62 were found to be irrelevant to the topic of the present study, 14 were review articles, 52 were case reports, and 50 were ex vivo studies.

The search with Scopus database resulted in 117 articles, of which 5 articles (1, 6, 8, 38, 39) were not identified in the MEDLINE database search and were found to be eligible for inclusion on the basis of their titles and abstracts.

The search with Embase database yielded no additional articles.

The manual search in the related articles and the reference lists of literature reviews and textbook chapters resulted in 3 additional articles that were not previously identified in the electronic search and that were eligible for inclusion on the basis of their titles and abstracts (40–42).

Full Text Evaluation The combined search through the electronic databases and the manual search resulted in a total of 27 studies (1, 3, 6, 8, 10, 14, 22–42), which were subjected to a suitability test in accordance with the criteria for considering studies for this review (Table 1). Six articles were found to be case reports, reviews, in vitro studies, or were found irrelevant to the topic of the present study. One article was not compatible with the VRF definition. In 5 articles non-endodontically treated teeth were included (and data could not be separated from endodontically treated teeth). In 7 articles the VRF was not confirmed according to the reference standards, and 14 articles provided no detailed data on clinical signs and symptoms and radiographic findings of the evaluated teeth. Eventually, none of the articles submitted to full text evaluation fulfilled the inclusion criteria (Table 2).

As a result, data extraction, methodological quality assessment, and data analysis could not be carried out. Thus, it was not possible to find substantial evidence regarding the diagnostic accuracy of the index tests for the diagnosis of VRF in endodontically treated teeth.

Discussion Numerous studies dealing with the diagnosis of VRF and the clinical and radiographic characteristics of the vertically root fractured teeth have been published (2, 3, 7–11, 14, 28, 29, 31, 34, 35, 39, 42–44). However, their study design, VRF definition, VRF confirmation methods, and evaluated clinical and radiographic data have been extremely variable, which resulted in publication of

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Clinical Research TABLE 2. Excluded Studies and the Reasons for Exclusion Study

Reason for exclusion*

Takeuchi et al, 2009 (33) Zadik et al, 2008 (37) Miyamoto et al, 2007 (30) Cohen et al, 2006 (25) Chambrone et al, 2006 (22) Tamse et al, 2006 (34) Cornelini R et al 2005 (26) Fox et al, 2004 (27) Llena-Puy et al, 2001 (28) Lustig et al, 2000 (29) Tamse et al, 1999 (3) Tamse et al, 1999 (14) Chan et al, 1999 (24) Youssefzadeh et al, 1999 (36) Chan et al, 1998 (23) Nicopoulou-Karayianni et al, 1997 (32) Testori et al, 1993 (35) Morfis et al, 1990 (31) Meister et al, 1980 (10) Kawamura-Hagiya et al, 2008 (38) Fuss et al, 2001 (8) Fuss et al, 1999 (6) Walton et al, 1984 (1) Pitts et al, 1983 (39) Rud et al 1970, (40) Abou-Rass M et al, 1983 (41) Gher et al, 1987 (42)

3, 4 4 1 3 1 5 1 1 4 5 5 5 3, 4, 5 5 1 3, 4 4 4 5 5 5 5 5 1 2, 5 3, 5 5

*Based on incompatibleness to the inclusion criteria of the systematic review (Table 1): (1) case reports, reviews, in vitro studies, and studies irrelevant to the topic of the current study; (2) incompatible with the VRF definition; (3) non-endodontically treated teeth are included; (4) lack of VRF confirmation according to the reference standards; (5) no detailed data regarding the clinical signs and symptoms and radiographic findings of the evaluated teeth.

inconsistent and confusing results (2, 4, 5, 9, 10, 25, 40). The aim of the present study was to systematically search and evaluate the available literature concerning the diagnostic accuracy of clinical and radiographic indices for the diagnosis of VRF in endodontically treated teeth by the means of a systematic review.

Systematic reviews use a systematic approach and explicit methodology to review and synthesize research evidence, aimed to minimize bias, and explicitly address the issues of the completeness of the identified evidence, assess the quality of the included studies and the studies’ combinability (15–18, 21, 45, 46). This systematic process requires a comprehensive literature search to identify as much of the relevant literature as possible (17, 18, 21, 47). It is recommended that a combined search of several electronic databases, together with other methods to retrieve studies (such as hand-searching of reference lists of relevant articles and book chapters), will be conducted (16–18, 21, 45, 47). In the present study a combined comprehensive literature search of several electronic databases and hand-search of related articles, literature reviews, and textbook chapters was conducted. On the basis of the study titles and abstracts, 27 possibly relevant articles were identified. To overcome heterogeneity of information, strict inclusion and exclusion criteria were applied to the identified studies.

Furthermore, it is crucial that the studies that are compatible with the inclusion criteria of the systematic review will be also subjected to methodological quality assessment to determine the strength of evidence (15). In the present study no article was in compliance with the criteria for entering the systematic review; thus methodological quality assessment was not carried out.

The ability to assess the diagnostic accuracy and clinical usefulness of clinical and radiographic parameters for the diagnosis of a target

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condition depends on the availability of a valid reference standard.

The appropriate reference standard should be carefully chosen and has to be based on a technique different from that of the tests being evaluated (16). The right selection of a reference standard is of paramount significance. In the present review, 3 types of reference standards were selected as acceptable for confirmation of the VRF (the target condition): confirmation during surgical flap procedure, confirmation after tooth extraction, and radiographic identification being a clearly discernable separation of segments of fractured root.

In the current systematic review only endodontically treated teeth were included, because it is expected that in vital teeth the signs and symptoms would be different and reflect pulp inflammation without periradicular changes (5, 24, 48, 49).

While considering the usefulness of a diagnostic evaluation, the relative value of possible health states resulting from the diagnosis and subsequent therapy should be taken into consideration (16).

When VRF diagnosis is made, a quick decision to extract the tooth or root is necessary. The reason is that the inflammation in the supporting tissues would otherwise lead to periodontal breakdown followed by the development of a deep osseous defect (1) and resorption of the bone facing the root fracture. Immediate treatment might prevent this unnecessary bone loss that might lead to complicated restoration of the area of extraction, if an implant should be considered the treatment of choice (2).

A diagnostic process is based on the combination of the patient’s subjective complaints and objective clinical and radiographic evaluation (50). The clinician is supposed to correlate the subjective and objective findings and formulate a diagnosis (50). In the case of VRF diagnosis, there is no known single pathognomonic sign, symptom, or radiographic feature to make the diagnosis easy and definitive (29). In 2006 in their article on demographic analysis of VRFs, Cohen et al (25) stated that one of the main reasons for the difficult diagnosis of VRF is the fact that the final diagnosis is based on constellation of several signs and symptoms rather than a single pathognomonic one. Therefore, the present review mandated the inclusion of detailed data regarding both clinical and radiographic evaluations (index tests) of the diagnosed teeth.

The most common signs and symptoms of VRF described in the literature are deep osseous defects especially on the buccal aspect of the susceptible teeth and roots, and highly located sinus tract (3, 10, 35). The deep osseous defect (deep probing), especially on the buccal aspect of the more susceptible teeth and roots (maxillary and mandibular premolars and mesial roots of the mandibular molars), were found in retrospective case series publications in high percentages and with statistical significance: Meister et al (10), 93%; Tamse (13), 64%; Testori et al (35), 78%; and Tamse et al (3), 67%. The sinus tract in the gingiva, especially when it is coronally located closer to the gingival margin (as opposed to the sinus tract in failing endodontic cases), is also a typical sign for the diagnosis of VRF. This type of sinus tract was found by Tamse et al (3) in 35% and by Testori et al (35) in 42% of the VRF teeth.

The most frequent radiographic features of VRF are the ‘‘halo’’ appearance, which is a combined periapical and perilateral radiolucency in one or both sides of the root, lateral periodontal radiolucency along the side of the root, or angular radiolucency from the crestal bone terminating along the root side (14, 32, 35). In mandibular molars, radiolucency in the furcation area can often be observed, coupled with the types of radiolucencies described above (34).

In the present systematic review no articles passed the inclusion criteria. That means that unfortunately, evidence-based data concerning the diagnostic accuracy and clinical effectiveness of the daily used clinical and radiographic dental evaluation for the diagnosis of VRF in

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Conclusions The evidence-based data regarding the diagnostic accuracy and usefulness of the commonly used clinical and radiographic evaluation methods for the diagnosis of VRF in endodontically treated teeth are lacking. That makes the determination of a fractured root often not distinctly objective and more of a prediction rather than a definitive diagnosis, as previously stated (25). In case a VRF is suspected, the clinician should be aware of the current conflict between the significant clinical importance of a quick and correct diagnosis and the lack of evidence-based data supporting the usefulness of common clinical and radiographic evaluation methods. Future evidence-based research regarding the diagnosis of VRF is needed and might possibly shed light on this clinical challenge.

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