Artun J, Krogstad O
Am J Orthod Dentofacial Orthop. 1987 Mar;91(3):225-32. doi: 10.1016/0889-5406(87)90450-1.
The present study was undertaken to examine whether excessive proclination of mandibular incisors results in gingival retraction. In patients with surgically treated mandibular prognathism, 29 with more than 10 degrees proclination of mandibular incisors and 33 with minimal change in incisor inclination during presurgical orthodontic phase were selected. A total of 21 and 19 patients, respectively, could meet for a clinical follow-up examination including Visible Plaque Index, Gingival Bleeding Index, probing pocket depth, and length of supracrestal connective tissue attachment. Study models and intraoral color slides were also made. The mean postoperative times at this examination were 7.8 (SD 2.5) and 8.1 (SD 2.8) years, respectively. Clinical crown height was measured on the study models taken before and after appliance therapy, at the 3-year postoperative control (check) and at the follow-up examination. The number of teeth with recession was determined from the color slides taken at the same intervals; the thickness of the symphysis was measured on the cephalograms taken before treatment. The results demonstrated significantly more increase in clinical crown height and significantly more teeth developing recession both during appliance therapy and during the period from removal of appliance to the 3-year postoperative control in the patients with excessive proclination than in the patients with minimal change in incisor inclination. The correlation coefficient between width of symphysis and increase in clinical crown height in patients with excessive proclination was statistically significant. Only minimal changes were observed from 3 years postoperatively to the follow-up examination. No differences in clinical measurements were observed between the groups and bone dehiscences were not found.
本研究旨在探讨下颌切牙过度前倾是否会导致牙龈退缩。在接受手术治疗的下颌前突患者中，选择了29名下颌切牙前倾超过10度的患者和33名在术前正畸阶段切牙倾斜度变化最小的患者。分别有21名和19名患者能够接受临床随访检查，包括可见菌斑指数、牙龈出血指数、探诊袋深度和龈上结缔组织附着长度。还制作了研究模型和口腔内彩色幻灯片。此次检查时的平均术后时间分别为7.8（标准差2.5）年和8.1（标准差2.8）年。在矫治器治疗前后、术后3年复查（检查）和随访检查时所取的研究模型上测量临床冠高度。根据相同间隔拍摄的彩色幻灯片确定出现牙龈退缩的牙齿数量；在治疗前拍摄的头颅侧位片上测量颏联合的厚度。结果表明，与切牙倾斜度变化最小的患者相比，前倾过度的患者在矫治器治疗期间以及从矫治器拆除到术后3年复查期间，临床冠高度的增加明显更多，出现牙龈退缩的牙齿也明显更多。在前倾过度的患者中，颏联合宽度与临床冠高度增加之间的相关系数具有统计学意义。从术后3年到随访检查仅观察到极小的变化。两组之间未观察到临床测量值的差异，也未发现骨缺损。
