安氏Ⅱ类错拔牙与非拔牙矫治病例牙槽嵴吸收的对比研究

Alveolar bone crest absorption between extraction and non-extraction treatment in Class II malocclusion

目的:了解拔牙与非拔牙矫治在治疗安氏II类错时牙槽嵴高度的变化情况。方法:选取双期矫治病例16例,摆式矫治器病例18例及拔牙矫治病例20例,治疗前后均拍摄上前牙根尖片,比较上前牙治疗前后"CEJ-AC距离"在三个治疗组中的平均变化量,并作方差分析及组间LSD-t检验。结果:治疗结束时,三治疗组的CEJ-AC变化量存在组间差别,并具有统计学意义(p<0.05),其中双期矫治组和摆式矫治器组的CEJ-AC分别增加了0.19mm和0.21mm,两组间无统计学差异(p>0.05),均小于拔牙矫治组的0.41mm,并有显著的统计意义(p<0.001)。三治疗组在治疗结束时的CEJ-AC距离均不超过2mm。结论:双期矫治、摆式矫治器及拔牙矫治在治疗安氏II类错时,均会造成牙槽嵴高度下降,其中拔牙矫治的下降程度较为严重,但三种方法均未造成具有临床意义的牙槽骨丧失。

Objective： Research the change in alveolar bone crest height among 2-phase treatment,pendulum and extraction treatment in Class II malocclusion. Method： 16 cases of 2-phase treatment, 18 cases of pendulum treatment and 20 cases of extraction treatment are chosen. Radiograms of maxillary incisors before and after treatment are analysed. Compare the change in CEJ-AC distance among three treatment groups. ANOVA and LSD-t test analysis are performed. Result： After treatment, there is statistical difference in CEJ-AC distance among three treatment group （P〈0.05）. CEJ-AC distance increase by 0.19 mm and 0.21 mm in 2-phses group and pendulum group respectively. There is no statistical difference between these two groups （P〉0.05）. CEJ-AC distance increase by 0.41 mm in extraction group,larger than any other group （P〈0.001）. After treatment, CEJ-AC distance in all three group are less than 2 mm. Conclusion： Alveolar bone crest height become lower after 2-phase treatment, pendulum and extraction treatment in Class Ⅱ malocclusion. This situation is more serious in extraction group than any other group. There is no kgn of alveolar bone lose in three treatment groups.