Recurrent mandibular dislocation is a rare condition that can have a negative impact on quality of life. Different surgical techniques are employed in the treatment of this condition, and the demand for maximum healthcare quality has contributed to the implementation of evidence-based clinical practice. The objective of this study was to determine the level of scientific evidence in articles reporting open surgical treatment for recurrent mandibular dislocation. A comprehensive search strategy was conducted to locate relevant articles in the PubMed and Web of Science databases on open surgical treatment for recurrent mandibular dislocation published between January 1974 and August 2014. These were classified into one of the five established levels/sublevels of evidence: the level of evidence was determined based on the classification proposed by the Oxford Centre for Evidence-Based Medicine. One hundred and fourteen articles were identified, 91 of which were excluded based on the eligibility criteria. Thus, 23 articles were selected for inclusion in the review. All of the selected articles were rated as level 4 (low quality) regarding the level of evidence. The present review revealed that articles on open surgical treatment for recurrent mandibular dislocation exhibit a low level of scientific evidence. Thus, further studies on this topic with greater methodological rigour are needed.
Diverse methods have been employed for the prevention and treatment of mandibular dislocation. In recent decades, a number of cases of this condition have been described, offering a wide variety of treatment options from non-surgical conservative approaches to invasive surgical procedures. However, divergent opinions remain regarding the most effective method.
Some surgical techniques have fallen into disuse, whereas others continue to be employed widely, even after more than 50 years since their advent. Eminectomy, an increase in the articular eminence with the use of grafts, the Dautrey procedure, and the placement of implants, such as miniplates, are well-known methods.
The decision regarding the most effective treatment should be based on scientific evidence. Evidence-based medicine is the conscious, explicit, judicious use of the best current evidence in decision-making with regard to care for the individual patient and involves combining clinical experience with the best available external clinical evidence available through systematic research, while also considering the patient’s preferences. This approach can reduce risks and offer the best treatment option based on the individual circumstances of each patient.
Studies that provide external evidence for application in clinical practice can be grouped according to their respective designs. When well-designed, executed, and reported, the systematic review and randomized controlled trial (RCT) offer the best evidence for most clinical issues. Other designs with a lower level of evidence include cohort studies, case–control studies, case series, case reports, basic and laboratory research, expert opinions, and non-systematic reviews. The Oxford Centre of Evidence-based Medicine (CEBM) levels of evidence represent one method used to assess the quality of individual studies.
As the level of scientific evidence on open surgical treatment for recurrent mandibular dislocation has not been evaluated previously, the aim of the present review was to apply the CEBM system to determine the level of evidence available in the literature considering the clinical aspects involved in recurrent mandibular dislocation. The aim of this study was to benchmark the best studies reported to date in this area. It was not intended to perform a meta-analysis of the reported outcomes from the selected studies unless they were studies providing a high level of evidence.
Materials and methods
The following question guided this study: What form of treatment for primary recurrent dislocation results in the lowest rate of recurrence?
A search strategy was developed to identify articles that made reference to open surgical treatment for recurrent mandibular dislocation ( Table 1 ). Searches were performed in the PubMed and Web of Science databases for articles published between January 1, 1974 and August 31, 2014. An additional manual search was performed in both databases. The lists of references from the two databases were exported into Mendeley Desktop version 1.12.4 computer program (Mendeley Ltd, London, UK) to identify any duplicate articles.
|PubMed||(“mandibular dislocation” OR “recurrent mandibular dislocation” OR “recurrent temporomandibular joint dislocation” OR “recurrent TMJ dislocation” OR “temporomandibular joint dislocation” OR “TMJ dislocation” OR “chronic mandibular dislocation” OR “chronic temporomandibular joint dislocation” OR “chronic TMJ dislocation” OR “chronic joint dislocation” OR “mandibular luxation” OR “temporomandibular joint luxation” OR “TMJ luxation”) AND (“open eminectomy” OR “TMJ eminoplasty” OR “augmentation of the articular eminence” OR “miniplate eminoplasty” OR “Dautrey’s procedure” OR “LeClerc procedure” OR “glenotemporal osteotomy” OR “capsular plication” OR capsulorrhaphy OR “bone plates”[MeSH] OR “dislocations/surgery”[MeSH] OR “Joint Instability/surgery”[MeSH] OR “Temporomandibular Joint Disorders/surgery*”[MeSH] OR “Oral Surgical Procedures*”[MeSH] OR “Osteotomy/methods”[MeSH] OR “Surgery, Oral/methods”[MeSH] OR “Surgical Procedures, Operative/methods”[MeSH] OR “Joint Capsule/surgery”[MeSH]) AND (“pain”[MeSH] OR “myalgia”[MeSH] OR “arthralgia”[MeSH] OR “range of motion, articular”[MeSH] OR “mouth opening” OR “interincisal distance” OR “mandibular movement” OR “protrusive movement” OR “chewing difficulty” OR recurrence[MeSH] OR relapse OR recidive OR “Treatment Failure”[MeSH] OR “Treatment Outcome”[MeSH] OR “facial paralysis”[MeSH])|
|Web of Science||(“mandibular dislocation” OR “recurrent mandibular dislocation” OR “recurrent temporomandibular joint dislocation” OR “recurrent TMJ dislocation” OR “temporomandibular joint dislocation” OR “TMJ dislocation” OR “chronic mandibular dislocation” OR “chronic temporomandibular joint dislocation” OR “chronic TMJ dislocation” OR “chronic joint dislocation” OR “mandibular luxation” OR “temporomandibular joint luxation” OR “TMJ luxation”) AND (“open eminectomy” OR “TMJ eminoplasty” OR “augmentation of the articular eminence” OR “miniplate eminoplasty” OR “Dautrey’s procedure” OR “LeClerc procedure” OR “glenotemporal osteotomy” OR “capsular plication” OR capsulorrhaphy OR “bone plates” OR “dislocations/surgery” OR “Joint Instability/surgery” OR “Temporomandibular Joint Disorders/surgery*” OR “Oral Surgical Procedures*” OR “Osteotomy/methods” OR “Surgery, Oral/methods” OR “Surgical Procedures, Operative/methods” OR “Joint Capsule/surgery”) AND (pain OR myalgia OR arthralgia OR “range of motion, articular” OR “mouth opening” OR “interincisal distance” OR “mandibular movement” OR “protrusive movement” OR “chewing difficulty” OR recurrence OR relapse OR recidive OR “Treatment Failure” OR “Treatment Outcome” OR “facial paralysis”)|
For the sample selection, two independent reviewers who had undergone a training and calibration exercise and who had experience with the topic read the titles and abstracts to determine whether the articles met the inclusion criteria for the analysis of the level of scientific evidence. Potentially relevant studies were retrieved and submitted to full-text analysis to determine whether the papers actually met the inclusion criteria. Disagreements between the reviewers were resolved by consensus. If necessary, a third reviewer was consulted. Letters to the editor and articles that did not address open surgical treatment for recurrent mandibular dislocation were excluded. Table 2 displays the eligibility criteria based on the intent of the present review and the filters employed.
|Articles on open surgical treatment for recurrent mandibular dislocation|
|Publication between January 1, 1974 and August 31, 2014|
|Full texts available electronically|
|Article could be categorized into one of the five established levels/sublevels of scientific evidence|
|Articles found not to address the topic under study after full-text analysis|
|Letters to the Editor/Editorial|
|Article published in any language other than English|
The articles selected in the first phase of the study were classified with regard to the level of scientific evidence based on the classification system proposed by the CEBM in 2009 ( Table 3 ), which is often employed for this purpose. The classification is based on the study design, but the quality of the study and the outcomes are also considered. The classification of a given study is generally based on a reading of the title and abstract. However, when the data extracted from these two sections is not sufficient, a reading of the full text is performed to determine the classification . A total of 10 sublevels of evidence determine one of four levels of recommendation. However, treatment costs as well as possible risks and benefits to the patient must be considered to establish a reliable level of recommendation. As valid data are scarce or even non-existent, recommendation levels were not included in the present review.
|Level of evidence||Meaning|
|1a||Systematic reviews (with homogeneity) of RCTs|
|1b||Individual RCTs (with narrow confidence intervals)|
|1c||‘All or nothing’|
|2a||Systematic reviews (with homogeneity) of cohort studies|
|2b||Individual cohort studies (including RCTs of low quality)|
|2c||‘Outcome’ studies, ecological studies|
|3a||Systematic reviews (with homogeneity) of case–control studies|
|3b||Individual case–control studies|
|4||Case series (as well as cohort and case–control studies of low quality)|
|5||Expert opinions with no explicit critical considerations or based on physiology or based on studies of low quality|
Studies in which the patients exhibited similar characteristics and were submitted to the same treatment were classified as homogeneous. Studies involving patients with different characteristics (e.g., comorbidities that favour dislocation) or submitted to different treatments (e.g., combination of procedures) were classified as heterogeneous.
Results of the database searches
The majority of the articles were found in the PubMed database and had an observational methodological design involving a non-probabilistic sample. Fig. 1 summarizes the results of the searches in the PubMed and Web of Science databases. One hundred and twelve references were found using the search strategy developed for the present review and an additional two references were located through the manual search. After the reading of titles and abstracts by the two independent reviewers, 84 articles did not meet the eligibility criteria or were missing the abstract and were therefore excluded, leaving 30 potentially relevant articles. The complete text of 29 references was obtained and submitted to detailed analysis. One of the references was not available electronically. Among the 30 references of interest, seven were excluded based on the reasons listed in Table 4 . Thus, 23 studies were selected for review ; two of these articles had been located through the manual search.
|Authors||Reason for exclusion|
|Vasconcelos and Porto, 2009||Previously published data|
|Cascone et al., 2008||Technical note|
|Wolford et al., 2001||Case report|
|Puelacher and Waldhart, 1993||Case report|
|Karabouta, 1990||Case report|
|Helman et al., 1984||Case report|
|Courtemanche and Son-Hing, 1979||Not available|
Level of scientific evidence of studies selected
All articles that met the eligibility criteria of the present review reported case series. The allocation of study design type, followed by the evaluation of the quality of the studies, resulted in all studies being assigned a level of evidence of 4. Table 5 shows the allocation of the studies in terms of the level of evidence.
|Author, year||Level of evidence||Description|
|Type of sample: homogeneous, heterogeneous, or comparative||Type of study: prospective, retrospective, or uncertain|
|Sahoo and Bhardwaj, 2013||4||Case series, homogeneous||Retrospective|
|Kummoona, 2010||4||Case series, heterogeneous||Uncertain|
|Vasconcelos et al., 2009||4||Case series, homogeneous||Retrospective|
|Guven, 2009||4||Case series, comparative||Uncertain|
|Guven, 2008||4||Case series, homogeneous||Uncertain|
|Medra and Mahrous, 2008||4||Case series, heterogeneous||Prospective|
|Cardoso et al., 2005||4||Case series, comparative||Uncertain|
|Kuttenberger and Hardt, 2003||4||Case series, homogeneous||Retrospective|
|Shibata et al., 2002||4||Case series, heterogeneous||Retrospective|
|Kobayashi et al., 2000||4||Case series, homogeneous||Uncertain|
|Holmlund et al., 1999||4||Case series, heterogeneous||Retrospective|
|Undt et al., 1997||4||Case series, homogeneous||Uncertain|
|Undt et al., 1997||4||Case series, homogeneous||Uncertain|
|Costas López et al., 1996||4||Case series, homogeneous||Retrospective|
|Srivastava et al., 1994||4||Case series, homogeneous||Retrospective|
|Sensŏz et al., 1992||4||Case series, heterogeneous||Retrospective|
|Iizuka et al., 1988||4||Case series, homogeneous||Uncertain|
|Gay-Escoda, 1987||4||Case series, heterogeneous||Uncertain|
|Pogrel, 1987||4||Case series, homogeneous||Retrospective|
|Oatis and Baker, 1984||4||Case series, heterogeneous||Uncertain|
|Lovely and Copeland, 1981||4||Case series, heterogeneous||Uncertain|
|Navarro et al., 2013||4||Case series, homogeneous||Uncertain|
|Martín et al., 2009||4||Case series, heterogeneous||Uncertain|