A Clinical Analysis of Tooth Size Discrepancy (Bolton Index) among Orthodontic Patients in Wuhan of Central China

The purpose of this study was to determine the total Bolton index （TBI） and anterior Bolton index （ABI）, evaluate the clinical significance of tooth size discrepancies and the influence of gender variation of mesiodistal tooth width on Bolton Index and estimate which tooth has the greatest influence on Bolton Index. A total of 110 pairs of pretreatment dental study casts （41 male and 69 female） were selected from patients treated in Department of Orthodontics of Union Hospital in Wuhan, China. A sliding dental Vernier caliper was used for the measurement of the mesiodistal tooth width. Descriptive statistical mean values, standard deviation, standard error of the mean values, coefficient of variance and the t-test were used for the statistical analysis of the data. The study found that TBI, ABI and the total sum of teeth width had no significant difference between male and female. Male group indicated that Bolton Index （BI） was mostly influenced by the width of lower right second premolar, whereas female group showed that BI was mostly influenced by the width of both the right and left maxillary lateral incisor.

临汾地区安氏Ⅲ类错患者Bolton指数的测量分析

目的:了解临汾地区安氏Ⅲ类错患者Bolton指数的分布规律。材料与方法:对120例恒牙安氏Ⅲ类错及个别正常的模型进行Bolton指数的测量分析。结果:安氏Ⅲ类错Bolton指数的均值男性大于女性,人数分布为正常组>过小组>过大组,Bolton指数在安氏Ⅲ类与正常间的比较差异有显著性。结论:安氏Ⅲ类错中Bolton指数过大可能是安氏Ⅲ类错形成的原因之一。

湖南地区正常恒牙合上下颌之间牙量关系的分析及临床应用

目的 :研究湖南地区正常恒牙合上下颌之间的牙量关系 ,为牙齿正畸诊断分析和矫治设计提供依据。方法 :精确测量正常恒牙牙合上下颌牙量 ,并进行了Bolton分析和相关资料对比。结论 :确立了湖南地区汉族恒牙牙合上、下颌之间牙量关系的正常比率 ,建立了计算上、下颌前 (全 )牙量的数学模型 ,为临床医师增加了进行错牙合畸形的诊断、矫治设计及判断预后的区域性标准。

运用3D数字模型观察前牙区牙齿大小的特征

目的运用3D数字模型观察前牙区牙齿大小的特征。方法选取汉族（蒙古人种）青少年正畸患者66例,其中男32例,女34例,11～14岁,平均12.8岁。制取上下牙牙合印模,通过电子扫描技术获得3D数字模型,对上下前牙区牙齿临床冠的高度、宽度和厚度进行测量,观察大小变化规律及其对正畸治疗效果的影响。结果正畸患者前牙Bolton指数略大于高加索人种均值（P〈0.05）;上颌侧切牙和下颌中切牙对前牙区Bolton指数的变化影响最大;上颌侧切牙舌侧边缘嵴厚度变化最大;同名上颌侧切牙和下颌中切牙临床冠宽度有一定差异;同名上颌尖牙及下颌尖牙临床冠高度有一定差异。结论前牙区牙齿大小有一定变化规律,Bolton指数在不同人种间有一定差异,影响前牙美学及良好咬合关系的建立,从而对正畸疗效稳定产生作用。