occlusal adjustments in TMD concluded the following: These conclusions were based largely on the fact that, despite many different scientific studies investigating this measure as a therapy, overall no statistically significant differences can be demonstrated between treatment with occlusal adjustment and treatment with placebo. The reviewers also stated that there are ethical implications if occlusal adjustment was found to be ineffective in preventing TMD. Orthodontic treatment, as described earlier, is sometimes listed as a possible predisposing factor in the development of TMD. On the other hand, orthodontic treatment is also often carried out in the belief that it may treat or prevent TMD. Another systematic review investigating the relationship between orthodontics and TMD concluded the following: A common scenario where a newly placed dental restoration (e.g. a crown or a filling) is incorrectly contoured, and creates a premature contact in the bite. This may localize all the force of the bite onto one tooth, and cause inflammation of the periodontal ligament and reversible increase in tooth mobility. The tooth may become tender to bite on. Here, the "occlusal adjustment" has already taken place inadvertently, and the adjustment aims to return to the pre-existing occlusion. This should be distinguished from attempts to deliberately reorganize the native occlusion. Surgery Attempts in the last decade to develop surgical treatments based on MRI and CAT scans now receive less attention. These techniques are reserved for the most difficult cases where other therapeutic modalities have failed. The American Society of Maxillofacial Surgeons recommends a conservative/non-surgical approach first. Only 20% of patients need to proceed to surgery. Examples of surgical procedures that are used in TMD, some more commonly than others, include arthrocentesis arthroscopy, meniscectomy, disc repositioning, condylotomy or joint replacement. Invasive surgical procedures in TMD may cause symptoms to worsen. Meniscectomy, also termed discectomy refers to surgical removal of the articular disc. This is rarely carried out in TMD, it may have some benefits for pain, but dysfunction may persist and overall it leads to degeneration or remodeling of the TMJ. Alternative medicine Acupuncture Acupuncture is sometimes used for TMD. There is limited evidence that acupuncture is an effective symptomatic treatment for TMD. A short-term reduction in muscular pain of muscular origin can usually be observed after acupuncture in TMD, and this is more than is seen with placebo. There are no reported adverse events of acupuncture when used for TMD, and some suggest that