利用正畸前移下颌第二、三磨牙关闭第一磨牙缺失间隙的临床观察

Clinical observation of closing the first molar gap by orthodontically moving forward second and third molars

目的研究下颌第一磨牙缺失后,用正畸的方法前移下颌第二、第三磨牙关闭缺牙间隙的过程与效果。方法选取2012年6月~2019年6月湖南中医药大学第一附属医院口腔正畸科接受治疗的20例下颌第一磨牙缺失患者作为研究对象,对比治疗前后下颌第二、第三磨牙轴倾度以及牙根长度的变化并进行统计学分析。结果治疗后,第一磨牙缺失间隙均关闭,磨牙关系恢复到Ⅰ类关系,牙根有少量吸收。治疗前后下颌第二、第三磨牙轴倾度变化,差异具有统计学意义(P<0.05);下颌第二、第三磨牙牙根长度变化,差异具有统计学意义(P<0.05)。结论直立前移下颌第二磨牙与第三磨牙关闭下颌第一磨牙缺失间隙是切实可行的,临床治疗过程中需注意牙根的吸收情况。

Objective To study the process and effect of closing the missing gap between the second and third mandibular molars with orthodontics after the first molars are missing.Methods Twenty patients with mandibular first molar loss treated in the department of orthodontics of the First Affiliated Hospital of Hu'nan University of Traditional Chinese Medicine from June 2012 to June 2019 were selected as the research subjects.The mandibular second and third molar axial inclination and root length were compared before and after treatment and analyzed statistically.Results After treatment,the missing gap of the first molar was closed,the molar relationship was restored to the ClassⅠrelationship,and the root of the tooth was slightly absorbed.The axial inclination changes of the second and third molars were statistically significant before and after treatment(P<0.05);and the root lengths changed of the second and third molars were statistically significant(P<0.05).Conclusion It is practicable to move the mandibular second molar and the third molar upright to close the missing gap of the first molar.It is necessary to pay attention to the root absorption during clinical treatment.