Mitchell D L, West J D
Am J Orthod. 1975 Oct;68(4):404-11. doi: 10.1016/0002-9416(75)90181-5.
A 37-year-old man with suspected ankylosis ("submerged" teeth, radiographically obliterated periodontal membranes, and sharp or ringing percussion tests) was subjected to attempted orthodontic movement. The maxillary canine and posterior segments were chosen as treatment areas. While the terms "light" and "heavy" are relative, forces ranging from 6 to 24 ounces were variants great enough in the areas treated to have elicited movement if movement were possible. After continuous forces had been applied for 110 days, measurements showed no movement in either maxillary quadrant.
一名37岁男性疑似患有关节强硬（牙齿“下沉”、X线片显示牙周膜消失、叩诊试验呈尖锐或清脆声），接受了正畸移动尝试。上颌尖牙和后牙段被选为治疗区域。虽然“轻”和“重”是相对的，但在治疗区域施加的6至24盎司的力变化幅度足够大，如果可能移动的话，本应引起牙齿移动。在持续施加力110天后，测量结果显示上颌的两个象限均未出现移动。
