Hypertrophy of the masseter muscle is relatively uncommon. Legg described this condition in 1880, about 130 cases have been reported since then.
The authors have recently experienced three cases of masseter hypertrophy. Case 1 was 17-year-old man whose chief complaint was bulging at the right angle of the mandible during forceful occlusion. Case 2 was a 44-year-old man with large swelling of the left cheek. Case 3 was a 20-year-old man with swelling at the left angle of the mandible.
CT proved effective in diagnosis
All three cases presented with asymmetry of the face and were treated surgically. Asymmetry of the face was objectively evaluated both pre-and post-operatively by CT imaging and P-A cephalometric radiography. Results of surgical correction were satisfactory.