Condylar surface forms in edentulous patients: examination findings.

The incidence of abnormal condylar surface forms was assessed by zonograms on edentulous patients who visited this department with various chief complaints other than temporomandibular disorder. The relation between these abnormal condylar surface forms and the conditions involved in the manifestation of the abnormalities was studied. Abnormal condylar surface forms were observed in 71% of the subjects. Bilateral abnormalities were found in 66% of these subjects: These abnormalities were classified into four types: erosion, flattening, osteophyte, and concavity. Those with erosion showed the highest incidence at 60.6%. The incidence of abnormal condylar surface forms was significantly higher in patients over 70 years old and/or in unstable denture wearers.