拔牙与非拔牙正畸治疗对微笑的美学影响

目的 研究拔牙与非拔牙正畸治疗对牙弓宽度以及微笑美学的影响.方法 选正畸临床治疗非拔牙患者和拔除4颗第1双尖牙患者各100例,分别对其矫治前、后模型上颌尖牙间和下颌尖牙间的牙弓宽度进行测量,测量点为尖牙长轴之牙根齿槽部的最突点,测量数据经统计学分析验证结果.结果 正畸矫治前两组患者的上颌及下颌牙弓宽度差异均无统计学意义(P＞0.05).矫治后,非拔牙组下颌宽度增加了0.88 mm(P＜0.001),上颌宽度增加了0.84 mm(P＜0.001);而拔牙组下颌宽度增加了1.64 mm(P＜0.001),上颌宽度增加了1.50 mm(P＜0.001).矫治后,拔牙组比非拔牙组下颌宽度增加了0.59 mm(P＞0.05),上颌宽度减少了0.10 mm(P＞0.05).结论 拔牙矫治与非拔牙矫治不但均未造成上下颌牙弓宽度之降低,反而引起明显的增宽.拔牙矫治导致牙弓缩窄,从而影响微笑的美观的结论不能成立.

Effect of orthodontic extraction treatment and non-extraction treatment on esthetical smile

Objective To investigate the effect of orthodontic tooth extraction and non-extraction on dental arch width and esthetical smile. Methods 100 patients treated without extraction and 100 patients treated by 4 first-premolars extraction were selected. The study models of the patients were measured before and after the treatment and compared statistically. Measurements were made in the maxillary and mandibular canine regions from the most labial aspect of the buccal axial surfaces of the canine roots. Results Before treatment, maxillary and mandibular arch widths were the same between both groups (P＞0.05). In non-extraction group, mandibular arch width of posttreatment was 0.88 mm larger than that of pretreatment (P＜0.001), and maxillary arch width of posttreatment was 0.84 mm large (P＜0.001). In extraction group, mandibular arch width of posttreatment was 1.64 mm larger than that of pretreatment (P＜0.001), and maxillary arch width of posttreatment was 1.50 mm large (P＜0.001). After treatment, the width of mandibular arch in the extraction group was 0.59 mm larger than that in the non-extraction group (P>0.05), while the width of maxillary arch in the extraction group was 0.10 mm less (P>0.05).Conclusion Both extraction treatment and non-extraction treatment do not result in narrower dental arch, but wider. The view that orthodontic extraction results in narrower arch widths and unaesthetic smiling is untenable.