单颌拔牙矫治Ⅱ类骨型患者对侧貌变化的影响研究

Effects of Single-maxillary Extraction and Orthodontic Treatment on Profile Changes in Patients with ClassⅡType Bone

目的:探讨上颌单颌拔牙掩饰性矫治生长发育完成期的Ⅱ类骨型患者侧貌的改变情况。方法:随机抽取30例Ⅱ类骨型错牙合患者,下颌后缩伴有上颌轻、中度前突,拔除上颌两颗第一前磨牙,应用活动翼矫治技术进行矫治,矫治后期配合正轴簧和Ⅲ类牵引。治疗前后拍摄X线头颅定位侧位片,对软硬组织进行测量分析。结果:平均治疗时间11个月,磨牙关系为完全远中关系,尖牙为中性关系;前牙覆牙合、覆盖正常,尖窝锁结关系良好。U1/SN、U1/NA、U1V明显减小;L1/MP、L1/NB、L1V没有统计学意义;颌凸角、上唇距、上唇凸距、上唇角和上唇-E减小,上唇基厚、面角、鼻唇沟角增大。下唇距、下唇基厚、下唇凸距、下唇-E、Z角、颏唇沟深度和颏唇沟角差异均无统计学意义。上颌前牙和上唇的突度明显改善。下颌前牙突度、下唇突度、颏部厚度和颏唇部沟角度没有变化,患者整体侧貌面型没有过多的改变。结论:上颌单颌拔牙矫治Ⅱ类骨型患者整体侧貌变化不大,此拔牙方法适合于均角或低角、下颌前牙轻度拥挤、颏部发育比较好的Ⅱ类骨型患者。

Objective To investigate the changes of the profile of skeletal ClassⅡbone type patients in completion period of growth and development after camouflage treatment by maxillary extraction.Methods Thirty patients with ClassⅡbone type were randomly selected,aged between 16 and 17 years old.The mild and moderate typeⅡmalocclusion was combined with mandibular posterior constriction with maxillary light and moderate protrusion.The first premolars of the upper jaw were removed,and the active wing treatment technique were used for the treatment,and cooperated with positive axis spring andⅢtype traction in the later period of treatment.The X-ray skull lateral radiographs were taken before and after treatment,and the soft and hard tissues were measured and calculated.Results The average treatment time was 11 months.The relationship between the molars is completely distant and the fangs are neutral.The anterior teeth are covered normally and the cusp locks are well connected.U1/SN,U1/NA,and U1V were significantly reduced;L1/MP,L1/NB,and L1V were not statistically significant,jaw angle,upper lip distance,upper lip protrusion,upper lip angle and upper lip-E decreased,upper lip base thickness,face angle,nasolabial angle increased.There was no statistical difference in the lower lip distance,the thickness of the lower lip,the convexity of the lower lip,the lower lip-E,the Z angle,the depth of the labrum and the angle of the labial lobe.The protrusion of the maxillary anterior and upper lip was significantly improved.There was no change in the anterior mandibular protrusion,lower lip protrusion,crotch thickness,and sacral lip groove angle,and there was no excessive change in the overall facial appearance of the patient.Conclusion There was no significant change in the overall profile of maxillary patients with ClassⅡbone type treated by single maxillary extraction.This extraction method is suitable for ClassⅡbone type patients with equal-angle or low angle,mild crowding of mandibular front teeth,and better mental development.