TYPE-II AND TYPE-III COLLAGEN IN MANDIBULAR CONDYLAR CARTILAGE OF PATIENTS WITH TEMPOROMANDIBULAR-JOINT PATHOLOGY

Purpose: This study was undertaken to examine the presence of type II and type III collagen in the cartilage of the mandibular condyle in di fferent types of temporomandibular joint (TMJ) pathology, including rh eumatoid arthritis (RA), to assess to what degree the newly formed tis sue is cartilaginous. Patients and Methods: Tissue samples from 46 TMJ surgery patients (37 women and 9 men; mean age, 37 years; range, 14 t o 76 years) were investigated, The samples were obtained at surgery mo stly from anteriorly situated osteophytes or the anterosuperior uneven articular surface of the condyle, Tissue sections were stained with h ematoxylin-eosin, toluidine blue, and Gomori's reticular stain. Type I I and type III collagens were demonstrated by immunohistochemical stai ning. Results: The amount of type II collagen was variable in the mand ibular condylar cartilage. Type III collagen was found in the new oste oid tissue as well as the new chondroid tissue that was synthesized in the most reactive situations.Conclusions: Type II collagen synthesis occurred mainly in condylar hypertrophy and the intermediate stage of internal derangement of the TMJ, Type III collagen, which is found in fibrous repair tissue, was also found in sites of repair of mandibular condylar cartilage, including RA and osteomyelitis.