Eagle Syndrome: Case Report

2 Eagle’s Sindrome: Case report. Summary The incidence of calcification of the stylohyoid ligament is high (84.4%) in patients with dental pathology. The link between osteoarthritis of the temporomandibular joint (TMJ) and Eagle Syndrome has been recognised however the pathogenetic link is not clear. In the case reported the calcification of the styloid process with osteoarthritis (OA) of the temporomandibular joint (TMJ) was associated with the inversion of the occlusal plane (OP). The correction of the OP was enough to resolve the patient's symptom of dysphagia. This leads us to believe that there is a common biomechanical basis for the lengthening of the styloid process and the osteoarthritis of the TMJ. The main factors involved in the pathogenesis of the OA of the TMJ are the change of the chemical composition of the synovial fluid and the alteration of its distribution within the joint. This is associated with the loss of coordination between the condyle and the disc which is due to the excessive stress on the joint such as that which occurs when the support in the posterior occlusal plane is lost. The relationship between the OA of the TMJ and the lengthening of the styloid process is clear but the pathogenetic link is not. In this study the distal inclination of the OP seems to be the factor responsible for the anatomical changes which are the cause of the patient's symptoms. Case Report A 60 year old woman presented with TMJ pain, vertigo, dysphagia and three months prior to the consultation she experienced an episode of locked jaw lasting one week, which resolved spontaneously. She started to suffer from loosening of her lower incisors. The clinical examination revealed restriction of movement on the horizontal plane (fig.1). The panoramic view showed advanced periodontal pathology with considerable reabsorption of the alveolar bone of the lower incisors (fig2). There was bilateral elongation of the styloid process (fig.3-fig.4-fig.5-fig.6) and advanced osteoarthiris of the TMJ (fig.7-fig.8). The cephalometric exam showed that the angle between the incisors was 1600. The angle between the Frankfurt plane and the occlusal plane measured - 50. The angle between the plane (hinge axis and orbital point) and the occlusal plane measured - 30 (+ 12.8). There was evidence of OA of the cervical spine (fig.9-fig.10). The examination of the movement of hinge axis of the mandible was carried out with electronic condylography according to the gamma program. The tracing showed an alteration of the quantity, quality, characteristics and symmetry of the movements of the mandible (see file). The study of the cast models of the mouth mounted on the articulator (SL Girrbach) revealed that the occlusal plane was inverted (fig.11-fig.12). Therefore it was decided to correct this by applying acrylic resin on the teeth of the lower prosthesis and by reducing the height of the upper crowns in order to maintain the same vertical dimensions. The corrections made on the articulator were transferred to the mouth of the patient by means of thermo plastic disc mould. The contact between the central incisors was reduced (fig.13-fig.14-fig.15-fig.16-fig.17-fig.18-fig.19). The patient was reviewed four months later. She did not show any signs of dysphagia, TMJ pain or restriction of the opening of the mouth (fig.20-fig.21). The symptoms of vertigo had diminished. The condylography showed improvement in the movement of protrusion with regard to quality, quantity and symmetry.