title: Incidence of Tooth Size Discrepancy in Different Groups of Malocclusion and its Relation to Extraction.
abstract: BACKGROUND
  For proper intercuspation, the teeth must be proportional in size. If teeth are mismatched, with unusually large teeth in one arch compared to the other, then an ideal occlusion cannot be attained. This study has been done to determine the prevalence of tooth size discrepancies among orthodontic patients in general and also between different malocclusion groups, sex, and to analyze the change in the degree of severity in Bolton discrepancy before and after the hypothetical premolar extraction.
  
  
  METHODS
  The study was carried out on randomly collected 100 pre-treatment dental casts. Tooth size analyses were performed on these pre-treatment models and Mesio distal tooth size ratios were measured as described by Bolton before and after various patterns of hypothetical extraction.
  
  
  RESULTS
  The results were statistically evaluated using ANOVA and paired samples t-test. 5 out of 100 patients are seen with severe Bolton discrepancy with Bolton values (BV) ranging above and below 2 standard deviation. Statistically insignificant difference is seen between males and females and also between various groups of malocclusion. The difference between the pre-treatment and post extraction BV was found statistically significant for the first premolar extraction and insignificant for others.
  
  
  CONCLUSIONS
  The results of this study indicate a new point of view to the question of which teeth to extract when evaluated for tooth size aspect only.
authors.affiliation: Reader, Department of Orthodontics & Dentofacial Orthopedics, Australia.
authors.forename: Rajkumar
authors.initials: R
authors.lastname: Gaddam
authors.affiliation: Assistant Professor, Department of Orthodontics & Dentofacial Orthopedics, Rajarajeswari Dental College & Hospital, Bengaluru, Karnataka, India.
authors.forename: Siddarth
authors.initials: S
authors.lastname: Arya
authors.affiliation: Professor and Head, Department of Orthodontics and Dentofacial Orthopedics, Bapuji Dental College and Hospital, Davangere, Karnataka, India.
authors.forename: K Sadashiva
authors.initials: KS
authors.lastname: Shetty
keywords: Anterior ratio; Bolton analysis; Bolton values; overall ratio; tooth size discrepancies