Hibi Hideharu, Sakai Kiyoshi, Oda Tomoo, Hattori Hisashi, Ueda Minoru, Sakai Masaru
Department of Oral and Maxillofacial Surgery, Nagoya University, Graduate School of Medicine, Showa-ku, Nagoya, Japan.
J Oral Maxillofac Surg. 2010 Aug;68(8):1783-7. doi: 10.1016/j.joms.2009.09.020. Epub 2010 May 13.
The aim of this retrospective study was to determine the success rate of an orthodontic skeletal anchorage system consisting of a locking plate and 2 self-drilling screws to intrude the upper molars and detect factors that contribute to its stability.
The subjects were 32 orthodontic and generally healthy patients who had skeletal anchorage plates placed supraperiosteally and unilaterally or bilaterally. The anchorage plate was considered successful if the plate remained stable throughout the period of intrusion of the upper molar without any movement, persistent pain, or infection and was then retrieved without difficulty. The success rates of the anchorage plate were statistically analyzed on the basis of clinically categorized variables.
The 32 patients comprised 6 male and 26 female individuals with ages ranging from 11.4 to 35.1 years. The overall success rate of the total 61 plates was 93.4%. No significant differences were observed among the respective success rates analyzed in accordance with gender, age, side of placement, and length of the screws. The thickness of the bony walls that supported the screws was significantly greater in the success group (mean 1.6 +/- SD, 0.2 vs 1.0 +/- 0.1 mm, P < .001).
Bone thickness is a critical factor in supporting the self-drilling screws and locking plate. Skeletal anchorage combining the plate and 2 screws promises a higher success rate with a thicker bone than with the threshold value of thickness that exists within the 1.1 to 1.4 mm range in the maxillary walls.
本回顾性研究旨在确定由锁定板和2枚自攻螺钉组成的正畸骨骼锚固系统压低上颌磨牙的成功率，并检测影响其稳定性的因素。
研究对象为32例正畸患者，一般健康，均在骨膜上单侧或双侧植入骨骼锚固板。如果在上颌磨牙压低期间，锚固板保持稳定，无任何移动、持续性疼痛或感染，且随后能顺利取出，则认为该锚固板成功。根据临床分类变量对锚固板的成功率进行统计学分析。
32例患者中，男性6例，女性26例，年龄在11.4至35.1岁之间。61块锚固板的总体成功率为93.4%。根据性别、年龄、植入侧和螺钉长度分析的各自成功率之间未观察到显著差异。成功组中支撑螺钉的骨壁厚度明显更大（平均1.6±标准差0.2 vs 1.0±0.1mm，P <.001）。
骨厚度是支撑自攻螺钉和锁定板的关键因素。与上颌壁厚度在1.1至1.4mm范围内的阈值相比，结合板和2枚螺钉的骨骼锚固在骨厚度更大时成功率更高。
