Diagnosis and reconstruction of the human temporomandibular joint after trauma or internal derangement.

This study reviewed the standardized records of 1100 patients with the symptoms of temporomandibular joint syndrome. Of these patients, only 4.5 percent required surgical intervention. The remaining patients were found to have masticatory muscle spasm and were treated by conservative dental methods. Over half the surgical patients had significant macrotrauma to the jaws in their past history. In addition, electromyographic measurement of the masseteric silent period duration in these patients did not reveal muscle spasm. These factors further serve to differentiate the surgical patient from the patient with myofascial pain dysfunction. The patients selected for surgery demonstrated moderate to severe joint disease and required arthroplasty with partial meniscectomy. A surgical technique is presented demonstrating the reconstruction of the meniscus with silicone implant. This same surgical technique is studied in 10 monkeys, and their joints are examined histologically. The results of surgery reveal that 87 percent of the patients reported improvement 1 year after surgery. In all patients complaining of temporomandibular joint clicking or crepitus, surgery produced complete alleviation of these symptoms. The results of surgery were also associated with a 62 percent increase of jaw opening. Histologic evaluation of the human meniscal resections revealed that in addition to an anatomic displacement of the meniscus, there are also significant cellular changes. These changes consisted of calcification, a decrease in cellularity, hyperemia, and a decrease in elastin content.