Orthognathic treatment and temporomandibular disorders - part 2

Medline, bibliographies and reference lists of identified publications and reviews, and personal communications with experts and specialists.

Randomised controlled trials (RCT), cohort studies and case-control studies were included if participants (of age 14 years or over) received orthognathic treatment. Studies were excluded if participants had either craniofacial syndromes or cleft lip or palate; a history of facial fractures from trauma; were undergoing orthognathic surgery purely to correct TMD; or orthognathic treatment and concomitant joint disc surgery; or, finally, if they were animal studies.

Data extraction was conducted independently by two reviewers, with discrepancies discussed until agreement was reached. A quality-assessment scale was constructed specifically for this study with sections for selection, performance, measurement and outcome, and attrition. A narrative synthesis is presented as meta-analysis was not either feasible or appropriate. Meta-analyses were carried out on the 12 studies that used the Helkimo index to classify TMD in patients at presurgery and post surgery.

Pain decreased after surgery for both self-reported symptoms and clinically diagnosed pain on palpation. However, postsurgical results were more varied for joint sounds. The percentage of patients with clicking had a tendency to decrease post surgery, but improvements in crepitus were questionable. The results from all meta-analyses in this review were subject to considerable statistical heterogeneity, and it was not possible to draw strong inferences relating to the percentage of orthognathic surgery patients with TMD with any degree of certainty.

Although orthognathic surgery should not be advocated solely for treating TMD, patients having orthognathic treatment for correction of their dentofacial deformities and who are also suffering from TMD appear more likely to see improvement in their signs and symptoms than deterioration.