Temporomandibular arthropathies: A retrospective study with histopathological characteristics.

BACKGROUND: To investigate the incidence of temporomandibular arthropathies diagnosed in a university center and to describe their histopathological characteristics. MATERIAL AND METHODS: Temporomandibular arthropathy cases with corresponding slides were selected from an oral and maxillofacial surgical pathology service. Cases of exclusively articular disc disease were not included. RESULTS: The mean age was 31.3 years with a predominance of females (69.7%). Of these diagnoses, 53.6% were unilateral condylar hyperplasia, 17.8% were bony ankylosis, 14.3% were degenerative joint disease, 10.7% were osteochondroma, and 3.6% were synovial chondromatosis. Condylar hyperplasia presented as thick fibrocartilage and cartilage nests in the cancellous bone. Bony ankylosis exhibited lamellar bone and nests of chondrocytes. Degenerative joint disease presented as an irregular layer of fibrocartilage with areas of clustered chondrocytes and calcified cartilage. Osteochondroma of the condyle exhibited hyaline cartilage and areas of new bone formation. Synovial chondromatosis presented as immature cartilaginous tissue and randomly arranged chondrocytes. CONCLUSIONS: The pathological alterations verified in these arthropathies involved diseases that were predominantly proliferative, i.e., unilateral condylar hyperplasia, osteochondroma and synovial chondromatosis of the tumor or pseudotumor type and bony ankylosis associated with callus formation of the reparative type, and less frequent degenerative changes for which the disease is so named.

Fixation of mandibular fractures with plates or miniplates: prospective study.

AIM: The choice of a more adequate internal fixation system in the treatment of mandibular fractures still originates controversy in the literature. The purpose of this study was to evaluate the effectiveness of internal fixation systems in the fixation of mandibular fractures, comparing indications and postoperative results between 2.4-mm plates and 2.0-mm miniplates. METHODS: A total of 42 consecutive patients with 71 mandibular fractures that had undergone either 2.4-mm plates (N.=20) or 2.0-mm miniplates (N.=22) were prospectively analyzed. Patients had a minimum follow-up of 6 months. Statistical analyses were made in the comparison between systems. RESULTS: There was no significant difference in the choice of systems as to age and characteristics of the fractures, but in patients with systemic diseases or chronic substance abuse, as well as in exposed fractures, with more frequency of 2.4-mm plates. 2.0-mm miniplates presented better recovery of jaw opening in the postoperative period. Temporary facial nerve deficit was observed exclusively in the case of extraoral approach. Both systems presented low rate of complications which required reoperation, however 2.0-mm miniplates presented better efficacy when compared to 2.4-mm plates. CONCLUSION: In conclusion, 2.0-mm miniplates should be always used when possible in the fixation of mandibular fractures, respecting their contraindications.

Changes in hemoglobin and hematocrit levels following orthognathic surgery of the mandible.

Red blood cell mass has been shown to recover rapidly with great decreases, as occurs in orthognathic surgery. However, blood loss during bilateral sagittal split osteotomy is considered minimal. The purpose of this study was to verify changes in hemoglobin (Hb) and hematocrit (Ht) levels following orthognathic surgery of the mandible. Data from 12 patients with a mean age of 27.5 years, from both genders, that were submitted to bilateral sagittal split osteotomy in the prognathism reduction were evaluated. No patient received blood transfusion during the procedure nor postoperatively. Procedures were performed by the same surgeon, with the use of reciprocating and sagittal saws. Levels of Hb and Ht were obtained in preoperative, one day postsurgery, and one, three and six weeks postoperatively. Statistical analyses were used to verify the difference in each group, and between periods. Patients lost a mean decrease in Hb of 2.0 g/dl, and in Ht of 5.2%. There was significant difference as to the levels of Hb (p=0.002) and Ht (p=0.010). These levels presented significant changes from immediate postoperative to six weeks for Hb, and to three weeks for Ht. It was concluded that a slow recovery of hemoglobin and hematocrit levels occurred following orthognathic surgery of the mandible.

Mineralization of stylohyoid ligament complex in patients with temporomandibular disorders and asymptomatic individuals: a comparative study.

The incidence of mineralization of the stylohyoid ligament complex, according to radiographic findings, was analysed in a group of patients with temporomandibular disorders (TMD), and compared with that of a control group of asymptomatic individuals (AI). Both groups were similar considering the prevalence of the female gender as well as the distribution of cases according to age. 'Elongated' was the most frequent radiographic appearance in both groups; 'partially mineralized' was the most frequent radiographic pattern in the TMD group; and the lower ramus was the most frequent location of mineralization in both groups. When comparing between groups and according to each class, there was only one significant difference in radiographic appearance, 'pseudoarticulated' being more frequent in the TMD group. We can conclude that the occurrence and characteristics of mineralization of stylohyoid ligament complex were similar in TMD patients and AIs.

Verification of the symmetry of the mandibular ramus in patients with temporomandibular disorders and asymptomatic individuals: a comparative study.

Some studies have reported that mandibular ramus asymmetries are more pronounced in patients with temporomandibular disorders. The symmetry of the mandibular ramus was verified in a group of patients with temporomandibular disorders and compared with that of a control group of asymptomatic individuals. Heights of the mandibular ramus and of the condyle and gonial angles were measured from panoramic radiographs. In the comparison of numerical values between dysfunction and asymptomatic groups there was no significant difference; when comparing sides within each group, there was a significant difference in gonial angle in the asymptomatic group. Using the formula: (R-L)/(R+L) x 100%, in the comparison between groups, there was a significant difference as to condylar height. With a subdivision in each group, having the value of 3% to calculated symmetry as a reference, there was no significant difference between groups. Comparing gender or age intervals in both groups, there was no significant difference. It was concluded that there was significant difference in calculated symmetry only as to condylar height between disorder patients and asymptomatic individuals.