Résumé
Bolton introduced the anterior and overall ratios that must exist between maxillary and mandibular teeth so as to obtain optimum occlusion. This study was conducted for the purpose of establishing the mean Overall Ratio [OR] and Anterior Ratio [AR] of the Bolton Analysis and the presence of Tooth size discrepancy [TSD] outside 2SD of the Boltoris mean in an orthodontic population, irrespective of -the type of malocclusion. The sample comprised 180pre treatment study casts with fully erupted and complete permanent dentitions from first molar to first molar. Selected randomly from records of the orthodontic patients. The mesiodistal diameters of the teeth were measured at contact points using digital calipers and the Bolton's analysis was carried out. The prevalence of tooth size discrepancies [TSDs] outside of 2 Standard Deviation [SD] from Bolton's mean were 18.8% for the overall ratio and 51% for the anterior ratio. Bolton tooth-size discrepancy is found in large number of Pakistani orthodontic patients which may effect orthodontic treatment goals and outcome. Thus, our results o support that Bolton analysis should be mandatory for every orthodontic case before starting the treatment