Linfen Wrong (occlusion) In Patients With Bolton Index

Bolton analysis of maloccluson patients in LinfenThis paper aims to study distributions of Bolton anterior and overall ratios among Class â… ,â…¡ and â…¢ malocclusion groups.The effection of any tooth extraction combinations,Angle's class, anterior ratio, overall ratio on Bolton index was also studied. Methods120 dental casts of orthodontic patients were selected randomly, 40 subjects of Angle class â… ,â…¡ and â…¢ were arranged with half man and half woman. 40 subjects with normal occlusion were choosed according to the standard in which 20 were females and 20 were males. Each tooth crown mesiodistal size between the first molar and the opposite molar of 160 dental casts was measured by electrical calliper .Anterior ratio , overall ratio and posterior ratio were calculated , according Bolton rate standards. Also Angle class â… ,â…¡ and â…¢'s ratios were counted under the condition of hypothetical tooth extrations 4/4/4/4 , 5/5/5/5, 4/4/5/5, 5/5/4/4. Results1.No statistically significant sex difference was found between anterior ratio , overall ratio and posterior ratio in the 3 malocclusions groups and normal occlusion but the means of males was larger than that of the female. As a result, females and males were combined to be a group.2.The distribution of number in Angle groups was as follows: the number of patients in the Bolton normal group was the most, it was the least in the Bolton big group.In the anterior ratio, no statistically significant differences were found in class â…  , class â…¡ and class â…¢. In the overall ratio the same results were found in class â…  , class â…¡ and class â…¢.3. The differences of anterior , overall and posterior ratios were statistically insignificant.4. Statistically significant differences were found between class III and other groups in the Bolton big group for the anterior ratio .But no statistically significant difference was found in anterior ratio of Bolton big group.In the anterior and overall ratios in the Bolton small group and normal group, there's no statistically significant difference.5. The percent of tooth-size discrepancy was increased on the condition of some kinds of extraction models.6. Satistically significant differences were found after extracting...