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Ankylosis of the temporomandibular joint (TMJ) is a severe disorder which leads to jaw function impairment and restricted mouth opening. The surgical approach to TMJ ankylosis can be performed according to different techniques. The present paper is a report of a bilateral post-traumatic case of TMJ ankylosis. The patient suffered bilateral condylar fractures as a consequence of a road accident and showed a limited mouth opening (22 mm) along with dental occlusion abnormalities. Conservative treatments were uneffective to improve jaw impairment, so a computerized tomography was requested for surgical treatment planning. Both temporomandibular joints showed severe ankylosis with a bone fragment located medially to the condyle. An arthroplasty with the interposition of a combined flap (temporalis muscle, fascia, periosteum) was performed. The post-treatment course was uneventful, and the patient has undergone physiatric rehabilitation immediately after the intervention. At the 5-years follow-up mouth opening was 46 mm. TMJ arthroplasty with the interposition of autogenous material is an effective technique to restore jaw function and to prevent recurrencies in cases of ankylosis.

The osteomuscular structure of the cranium presents peculiar anatomic characteristics that aim to preserve the noble organs that are housed inside or are adjacent to them. This is also true of the condylar region which protects the cranial cavity from forces transmitted to the glenoid cavity by the condyle in traumatism to the facial region and above all the genial symphysis. These factors act as "force breakers" to prevent the condyle penetrating the middle cranial fossa. Of these the most important is the presence of a line of minor resistance at the level of the condyle neck which is often the site of a protective fracture. However, the dislocation of the condyle in the middle cranial fossa is an occurrence that is reported in the literature, albeit very rarely; the fracture of the glenoid fossa with an intact mandibular condyle and without evident dislocation of the latter is even more rare. The paper reports the case of a 22-year-old male patient who was injured in the submental area leading to loss of conscience. CT revealed that the left mandibular condyle was intact whereas there was a comminuted fracture of the roof of the glenoid fossa and two fractures at the mandibular level. The patient also presented left otoliquorrhea. The glenoid fracture was not complete and therefore the mandibular condyle did not show evident dislocation nor was it necessary to resort to surgical or non-surgical treatment. After the reduction and restraint of the two mandibular fractures, occlusion was correct and the position of the left condyle was appropriate following X-ray control, even if the glenoid cavity was partially fractured. Otoliquorrhea resolved spontaneously after about three days and did not require any treatment. The case described here, which was recontrolled after some time, presented excellent functional results demonstrating that conservative treatment of the glenoid cavity fracture was the correct therapeutic choice.

The paper reports a study of the relationship between the upper head of the pterygoid muscle and the temporomandibular joint disc. Using optical microscopy, TMJ serial sections of 10 human embryos and fetuses aged from 6 to 22 weeks were examined. From the observation of serial sections, it appears that from the start of histogenesis the lateral pterygoid muscle is in contact with the condylar blastema and later with the disc and the condyle. A fibrous attachment was detected between the muscle tendon and the meniscus, and oxytalan and elastic fibres were observed near this attachment.

Clinical and radiographic examinations of the temporo-mandibular joint are difficult to perform. Alternative diagnostic methods, for example, double contrast arthrotomography, computerized tomography, magnetic resonance imaging, and arthroscopy raise hopes for improved diagnostic accuracy. The purpose of this paper is to review and evaluate the potentials and limitations of this new technique.

On the base of some papers previously published on the anatomy and physiology of the Tmj the Authors have studied the intracapsular dynamics of the cranio mandibular articulation. The intracapsular movements are guided by some biomechanical restrictions that have been cautiously studied and analized. The biological advantages of the presence of the meniscus between the two articular surfaces is clearly stated. The role of the lateral capsular ligament in stabilizing the disk over the condyle head is clearly demonstrated on the base of previous studies both on the microscopic and macroscopic anatomy of the ligament and the capsule. According to the Authors the disk is stabilized over the condyle head by the lateral capsular ligament, the temporomandibular ligament and by the histological structure of the meniscus that permits its compression and distorsion during the mandibular movements. The disk distorsion increases the anatomical correspondence between the intracapsular structures.

The paper analyses the post-traumatic pathology of the T.M. joint in patients in a dynamic growth phase with reference to prognostic and therapeutic factors. After a critical review of the literature, the lack of a common viewpoint and the importance of personal experience are underlined.