Seena Patel DMD, MPH
There is insufficient evidence to suggest the use of cognitive-behavioral therapy (CBT) over other interventions in the treatment of temporomandibular disorders (TMD).
In patients with temporomandibular disorders, is CBT more effective compared to other dental interventions in managing the pain and dysfunction?
Two reviewers independently conducted a comprehensive search of five electronic databases, one of which was Chinese, through April 2009 and also hand-searched Chinese professional journals and references. They also selected studies, extracted data, and discussed disagreements until resolved. They contacted the authors of the included studies to resolve any questions. The reviewers included randomized controlled trials (RCTs) or semi-RCTs that tested CBT against no intervention or another dental intervention on patients aged 18 or older who were clinically diagnosed with TMD. Two reviewers assessed risk using the Cochrane Risk of Bias tool and analyzed heterogeneity to determine the appropriateness of meta-analysis. The reviewers chose the primary outcomes as pain intensity, pain-related interference, jaw use limitations, and negative mood.
Out of 323 studies identified, five were included (three RCTs and two "semi-randomized controlled trials"). The duration of each study was different. A meta-analysis was not performed. The reviewers reported a few cases of statistically significant differences between groups. One study comparing the CBT group vs. the education only group showed a statistically significant difference for improved outcomes in the CBT group. The CBT vs. no treatment group showed no differences in outcomes. Overall, the authors report that there was no statistically significant difference showing that CBT was more effective.
There is insufficient evidence either for or against the use of CBT over other interventions for the treatment of TMD. However, weak evidence, based on the methodological quality and small number of included studies, suggests that CBT may be beneficial for the treatment of TMD to reduce pain and jaw limitation.
Source of Funding:
There was no source of funding reported.
Importance and Context:
TMD can reduce quality of life and be a source of chronic pain. These conditions can have psychological comorbidities, such as depression and anxiety, which can affect pain perception and quality of life. CBT is a minimally invasive approach to managing chronic pain, which targets the psychological aspects of the disorder. It focuses on changing negative thoughts regarding pain, relaxation, and other behavioral therapies. CBT strives to reduce maladaptive behaviors and increase positive, healthier behaviors in the management of chronic pain. Unfortunately, there is a lack of sufficient, high quality evidence investigating its efficacy on TMD.
Strengths and Weaknesses of the Systematic Review:
The strengths of the SR included a comprehensive literature search, adequate number of reviewers, inclusion of RCTs and semi-RCTs, clearly outlined inclusion and exclusion criteria, and that a quality assessment was conducted. Further, a risk of bias was also completed. There were a few limitations of the SR. The grey literature was not searched, and publication bias was not assessed. The decision to determine whether a meta-analysis could be done should have been decided prior to performing one. In the end, a meta-analysis was not actually done. Further, an exact question that the SR strove to answer was not clearly defined.
Strengths and Weaknesses of the Evidence:
While the SR included three RCTs for evaluation, the other two were only semi-RCTs. The duration of these studies varied considerably (eight weeks to twelve months), making it difficult to compare results among the studies. Further, a meta-analysis was not performed because of these differences in follow-up duration, the heterogeneity of the included studies, and the differences in comparison groups and follow-up times, some of which were short. Only one study clearly described allocation concealment in their design. Also, adequate blinding of participants, clinical examiners, and outcome evaluators were not outlined in all of the studies. Further, the studies all had a small number of participants (22-76), and the other interventions employed were not described in detail. This makes it difficult to adequately compare outcomes. The evidence is insufficient to recommend any definitive conclusions.
Implications for Dental Practice:
This SR reveals that there is insufficient evidence for or against the use of CBT in the management of TMD. Another systematic review published in 2011, consisting of few RCTs with high risk of bias, reported weak evidence for the use of psychosocial interventions in the treatment of chronic orofacial pain. A small RCT published in 2012 revealed positive results in patients receiving CBT and hypnosis compared to standard TMD treatment. Newer evidence may influence the true efficacy of CBT in the treatment of TMD, demonstrating a need for well-designed RCTs with larger sample sizes that follow the CONSORT guidelines and the Research Diagnostic Criteria for temporomandibular disorders. References: 1) Aggarwal VR, Lovell K, Peters S, Javidi H, Joughin A, Goldthorpe J. 2011. Psychosocial interventions for the management of chronic orofacial pain. Cochrane Database Syst Rev., 9(11). 2) Fernando M et al. 2012. Enhancing the efficacy of treatment for temporomandibular patients with muscular diagnosis through cognitive-behavioral intervention, including hypnosis: a randomized study. Oral Surg Oral Med Oral Pathol Oral Radiol, 113:81-89.