Methodological quality of a systematic review on physical therapy for temporomandibular disorders: influence of hand search and quality scales

The validity of a systematic review depends on completeness of identifying randomised clinical trials (RCTs) and the quality of the included RCTs. The aim of this study was to analyse the effects of hand search on the number of identified RCTs and of four quality lists on the outcome of quality assessment of RCTs evaluating the effect of physical therapy on temporomandibular disorders. In addition, we investigated the association between publication year and the methodological quality of these RCTs. Cochrane, Medline and Embase databases were searched electronically. The references of the included studies were checked for additional trials. Studies not electronically identified were labelled as “obtained by means of hand search”. The included RCTs (69) concerning physical therapy for temporomandibular disorders were assessed using four different quality lists: the Delphi list, the Jadad list, the Megens & Harris list and the Risk of Bias list. The association between the quality scores and the year of publication were calculated. After electronic database search, hand search resulted in an additional 17 RCTs (25%). The mean quality score of the RCTs, expressed as a percentage of the maximum score, was low to moderate and varied from 35.1% for the Delphi list to 54.3% for the Risk of Bias list. The agreement among the four quality assessment lists, calculated by the Interclass Correlation Coefficient, was 0.603 (95% CI, 0.389; 0.749). The Delphi list scored significantly lower than the other lists. The Risk of Bias list scored significantly higher than the Jadad list. A moderate association was found between year of publication and scores on the Delphi list (r = 0.50), the Jadad list (r = 0.33) and the Megens & Harris list (r = 0.43)

Physical Therapy and Temporomandibular Disorders

Summary Physical therapy (PT) is a well-recognized, efficient conservative method for the managementof pain and movement dysfunctions of musculoskeletal origin throughout the body. In alifetime, about 2/3 of the population presents jaw disorders (called temporomandibulardisorders, TMDs), as part of these musculoskeletal problems. Hence the objective of this PhDdissertation was to evaluate the effectiveness of PT for treating pain and movementdysfunctions in TMDs. Previous studies were reviewed using the Cochranesystematic reviewmethod.This review resulted in 28 randomized, controlled trials (RCTs) with a high variationin research methods, PT modalities and outcome variables. It showed that PT results in lesspain, a better mouth opening and improved jaw function over time. However, comparisonsbetween PT interventions and placebo interventions or with a control group without treatmentwere equivocal. Combinations of PT modalities seem to result in more decrease of pain andimpairment than single PT modalities but it was impossible to conclude which combinationwas more effective.A subsequent study analyzed the influence of study characteristics on the degree of pain enmobility improvement, both before to after the PT treatment, and between the different PTtreatments. Respectively, 70% and 63 % of the studies reported significant improvementbefore to after treatment for pain and mobility There is an increased chance on finding painimprovement after treatment if the follow-up is longer than 30 days, ifmore subjects areincluded in the study and if the subjects received real therapy (in contradiction to placebotreatment or no treatment). There is an increased chance on finding mobility improvementafter treatment if subjects received real therapy and if they received more treatments.Making a judgement about the effectiveness of PT by means of a systematic review alsodepends on the completeness of the included studies and the quality of these studies. Hence,we analyzed the effect of hand search on the number of identified studies and the effects offour different quality assessment tools. An electronic search strategy in the databases Pubmed,Embase and the Cochrane Central Register of Controlled Trials resulted in 52 studies. Themethod of hand searching resulted in an extra 17 (25%) studies. The estimated quality of thestudies was different according to the different assessment tools used.An additionalinvestigation of the association between publication year and the methodologcal quality of thestudies resulted in a better quality for the most recent studies if assessed with the Delphi list,the Megens & Harris list and the Risk of Bias list.An important overall finding however was that the methodological quality of the studiesappeared to be low. This shortcoming, inspired to conduct two long-termrandomisedcontrolled studies One study including patients suffering from masticatory muscle pain andanother study on patients with anterior disk displacement (closed lock)of thetemporomandibular joint (TMJ). By means of validated measurements of pain and mobilitywe analyzed the effect of PT. Patients willing to cooperate were randomly assigned to either aPT group or a control group. All patients were informed and instructed by one researcherabout normal jaw function. The information and instructions were repeated at all evaluationtimes (at 0, 3, 6, 12, 26 and 52 weeks). In addition to the informationand instructions, thepatients randomized to the PT group received nine PT sessions scheduledover six weeks. ThePT sessions started with repeating the information and instructions, followed by stretch andrelaxation techniques for the painful muscles. For the patients with locked jaw, rotationexercises and mobilization techniques were applied subsequent to the stretch and relaxationtreatments. All these techniques were demonstrated to the patient to beincluded in a homeexercise program. They were encouraged to do this home program for at least six weeks afterfinalising the PT sessions. In both studies, all pain variables decreased and all functionvariables increased significantly over time, both for the treatment andthe control group.However, since we did not find a difference between the treatment and the control groups, theeffect of PT has to be considered non-specific.status: publishe

A multicentre study to diagnostic accuracy of temporomandibular pain tests

Objectives: To study the diagnostic accuracy of the clinical examination of the Research Diagnostic Criteria (RDC) and of the dynamic and static pain tests for the recognition of temporomandibular disorder (TMD) pain. Methods: A blind examination, including all clinical tests needed for a RDC diagnosis of TMD pain, and the dynamic and static pain tests, was performed in 125 chronic TMD pain patients, 88 chronic dental pain patients, and 121 pain-free subjects. Allocation was based upon the results of an oral history and a dental examination. As indicators for diagnostic accuracy, sensitivity and specificity of the RDC examination and of the dynamic and static pain tests were compared to recommended levels of .70 and .90, respectively. Results: For the RDC examination, high sensitivity (.88), but lower specificity (.45-.71) was found. The specificity did not reach its recommended level. For the dynamic and static pain tests, specificity (.84-.91) and sensitivity (.65) did not differ from the recommended levels. Comparing the outcomes of the two examinations showed that the positive likelihood ratios of the dynamic and static pain tests were higher (p<.001), while the negative likelihood ratios of the RDC examination were lower (p<.01). Conclusion: For the confirmation of a suspected TMD origin of orofacial pain, it is better to rely on the dynamic and static pain tests. To rule out a TMD origin, more value should be attached to the RDC examination (no funding sources)

Accuracy of RDC/TMD examination and dynamic/static tests

Objectives: To study the diagnostic accuracy of the clinical examination of the Research Diagnostic Criteria (RDC) and of the dynamic and static pain tests for the recognition of temporomandibular disorder (TMD) pain and to improve the RDC accuracy by 1) changing the myofascial pain cutoff of 3 painful muscle palpation sites, or 2)omitting unreliable palpation sites. Methods: In 4 European dental faculties, a blind examination was performed in 125 chronic TMD pain patients, 88 chronic dental pain patients, and 121 pain-free subjects. Allocation was based upon the results of an oral history and a dental examination. Results: Sensitivity and specificity of the RDC were .88 and 45-.71, respectively. Increasing the myofascial pain cutoff better met the recommended levels for specificity and sensitivity of .70 and .90, respectively. When unreliable muscle palpation sites (i.e., the intraoral and submandibular sites) were omitted, the accuracy of the RDC/TMD examination did not change. For the dynamic and static pain tests, sensitivity (.65) and specificity (.84-.91) did not differ significantly from the recommended levels. Conclusion: A suspected TMD origin of orofacial pain is best confirmed by pain on the dynamic or static tests, while it is better denied by a negative outcome of the RDC examination. The intraoral and submandibular palpation sites of the RDC examination do not contribute to its diagnostic accuracy and can better be omitted, while the cutoff for a myofascial pain diagnosis should be increased