فهرست نشریات علمی دسترسی آزاد ایران

Aim: The Bolton analysis is commonly used by orthodontists. The Bolton ratios of different populations are significantly different from the standard values of Bolton. This study aimed to examine Bolton's anterior and overall ratios in various malocclusion types in Mashhad, Iran, in comparison to the Bolton’s standards.Methods: This descriptive-analytical study included 240 study models of patients (121 males and 119 females) in four groups (n= 60 cases) of normal occlusion, Class I, Class II, and Class III. The mesiodistal dimensions of the teeth were measured twice using a digital caliper. The anterior and overall ratios of Bolton were calculated. Kruskal Wallis, Chi-square, one-way ANOVA, Tukey’s post hoc test and one-sample t-test were used for statistical analysis. P-value<0.05 was considered as significant.Results: The mesiodistal width of the maxillary lateral incisors in normal occlusion cases was greater than in Class I, Class II, and Class III malocclusions (P<0.05). Conversely, the mesiodistal width of the maxillary first and second premolars was the greatest in Class II and the smallest in Class III malocclusion (P<0.05). There was no correlation between Bolton ratios (anterior and overall) and gender or malocclusion groups (P>0.05). Additionally, the anterior ratio was significantly higher than Bolton's standard in Class I and III malocclusion groups (P<0.05). The overall ratio of the normal occlusion group was significantly lower than Bolton's original ratio (P<0.05).Conclusion: The size of premolars in Class III patients is smaller than in Class II which is consistent with the type of malocclusions. In Iranian individuals with normal occlusion, the overall Bolton’s ratio is higher than the standard.