Arthrosis of the hand was studied in 136 dentists 33-69 yr of age on a joint-by-joint basis. A random sample of 940 persons of similar age from the general population served as controls. The prevalence of arthrosis was significantly higher in male than female dentists. Male dentists tended to have a higher and female dentists a similar prevalence of arthrosis as compared to the respective controls. The proportion of arthrotic distal interphalangeal (DIP) joints of all arthrotic joints of the hands was in both male and female dentists greater than that in controls, especially below the age 50, suggesting that arthrosis of the DIP joints of fingers develops earlier in dentists than in controls. This might result from the extensive use of the precision grip in dentistry. Arthrosis of the DIP joint of the index finger was not associated with the pinch power between the thumb and index finger, indicating good preservation of manual function in spite of increasing degenerative changes in hand joints with advancing age.