108 страниц. 2014 год. LAP Lambert Academic Publishing A retrospective study was conducted to investigate the effects of premolar extractions on Bolton overall ratios and tooth size discrepancies in Dakshina Kannada population. The materials used were 264 pretreatment plaster casts from Department of orthodontics of various dental colleges of Dakshina Kannada. Mesiodistal tooth widths were measured using digital vernier calipers. Bolton’s ratios were determined before and after hypothetical premolar extractions in various combinations.The results of this study showed:The significantly notable decrease in overall ratios for all second premolars and maxillary second and mandibular first premolars for Dakshina Kannada population.From the results we can conclude that generally the tooth material ratio of Dakshina Kannada population shows a mild maxillary tooth material excess. In patients requiring extraction, all first premolars or maxillary first and mandibular second premolar extraction should be preferred.