正常[牙合]与错[牙合]患者第三磨牙先天缺失的比较研究被引量：2

Study of the third molar development in normal occlusion and malocclusion young adults

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摘要目的探讨正常[牙合]与错[牙合]青年第三磨牙的发育情况。方法对相同年龄分布的青年正常[牙合]个体97人和错[牙合]患者186人进行临床检查与X线测量分析，对第三磨牙存在与缺失、缺失部位、牙胚位置及其与[牙合]平面夹角等进行对照研究。统计分析为卡方分析和t检验。结果以人计数的第三磨牙缺失率正常[牙合]个体为46．36％，高于错[牙合]患者29.03％；以牙计数的第三磨牙缺失率正常[牙合]个体21．65％也高于错于[牙合]患者的16．67％，而且正常[牙合]个体上颌第三磨牙的缺失尤其高于错[牙合]患者；正常[牙合]和错[牙合]患者上颌第三磨牙的缺失率均高于下颌；发育中的第三磨牙与[牙合]平面的夹角，无论是正常[牙合]和错[牙合]患者，均为下颌大于上颌，其中男性错[牙合]患者下颌磨牙的夹角大于女性患者及正常[牙合]男性。在错[牙合]患者中牙列存在间隙的患者及存在其他牙齿异常苦。第三磨牙的缺失率显著增高。结论汉族正常[牙合]个体第三磨牙缺失率高于错[牙合]患者；上颌第三磨牙比下颌磨牙更易缺失；在发育过程中下颌第三磨牙比上二颌磨牙更加倾斜。 Objective to investigate development of third molar in two groups of young adults of normal occlusion and malocclusion. Methods ninety-seven of young adults with normal occlusion and one hundred eighty-six with malocclusion were examined clinically and X ray radiograms were measured. Evaluations included present or absent of third molar, the position of the third molar germs, the angulation of the developing third molar. Chi square and t test was undertaken between the groups. Results the incidence of third molar agenesis in young adults with normal occlusion was significantly higher than that of the malocclusions,. The incidence of missing upper third molar was higher than that of the lower ones in both the normal occlusion group and the malocclusion group, and the incidence of the upper third molar agenesis in normal occlusion was higher than that of the malocclusion group. Considering the angle between the developing third molar and the occlusal plane, the angle of the lower third molar was bigger than that of the upper ones in both groups, and the angle of the lower third molar to occlusal plane in malocclusion males was bigger than that of the females with malocclusion and the normal occlusion subjects. Conclusions The third molar was more likely to be congenital missing in normal occlusion than malocclusion, and the missing upper third molar was more than that of the lower ones. The lower third molar tends to be more missal proclined than that of the upper ones when developing.

作者李巍然周伟华

机构地区北京大学口腔医学院正畸科

出处《口腔正畸学》 2006年第3期115-118,共4页 Chinese Journal of Orthodontics

关键词第三磨牙缺失错[牙合] third molar congenital missing malocclusion

分类号 R783.5 [医药卫生—口腔医学]

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