RESUMO
Aim: This study was conducted to establish the Bolton’s ratios’ norms ((The mean Overall Ratio (OR) and Anterior Ratio (AR) norms)) in 100 Karnataka subjects and to compare it with the overall ratio and anterior ratio of the Bolton’s analysis which would be an aid in diagnosis and treatment planning of orthodontic cases. It will also help in determining functional and esthetic outcome of the case. Methodology: Epidemiological survey was carried out for 100 subjects (50 males and 50 females), 14-25 years of age. The study groups were from Karnataka state in India. Every individual was assessed for occlusal traits and good quality impressions were taken for 100 selective individuals. Mesiodistal tooth dimensions were measured from right first permanent molar to left first permanent molar in maxillary and mandibular arches. Measurements were taken using digital vernier caliper. Anterior and overall ratio were calculated for each model. Data was statistically analysed by using statistical package for social sciences (SPSS) software. Results: The results showed that the overall ratio was 92.23 for males and 91.78 for females. The anterior ratio was 77.87 for males and 77.69 for females. The study indicated that there was statistically significant difference between the overall ratio and anterior ratio of Karnataka subjects and Caucasian subjects. Conclusion: The study concluded that inter arch tooth size a relationship varies and are specific.