ABSTRACT
Many difficulties encountered during the finishing-phase of orthodontic treatment arise due to lack of intermaxillary tooth-size matching. Bolton ratio is one of the most useful calculations for precise orthodontic diagnosis as it shows if there is a correct ratio between dental proportions. The aim of this study was to compare both the Bolton anterior and overall ratios for a Saud Arabian sample of different classes of malocclusion and also to find if there is any gender difference. This study involved one hundred sixty subjects divided into three malocclusion groups: Angle's Class I, Angle's Class II, and Angle's Class III. Tooth size measurements, Bolton anterior and overall ratios were performed for the study casts of the patients using the software program Ortho-one. Statistical analysis was done using one-way analysis of variance to check for intergroups differences then independent sample t-test was done to find any sexual dimorphism. The results showed that there is no significant difference between Class I, Class II, and Class III malocclusions. Also no significant gender differences were found in Bolton anterior and overall ratios