Effect of intermaxillary tooth-size discrepancy on accuracy of prediction equations for mixed dentition space analysis
- 169 Downloads
Correlation-statistical methods are widely used for prediction of size of unerupted permanent canines and premolars in mixed dentition space analysis. The present study was planned to evaluate the effect of selecting dental study casts with no intermaxillary tooth-size discrepancy on the accuracy of predicting mesiodistal widths (MDWS) of permanent canines and premolars.
Bolton ratios were calculated for all the screened study dental casts fulfilling the inclusion criteria. Subjects were divided into two groups. Group A: all subjects with no intermaxillary tooth-size discrepancy within ±2 SD (Standard deviation) of the mean values. Group B: increased percentage of subjects with intermaxillary tooth-size discrepancy beyond ±2 SD (Standard deviation) of the mean values.
Linear regression equations were established for both maxilla and mandible in both the groups, with different tooth combinations as independent variables. Validation of best possible regression equations was done on an independent set of 40 subjects. The actual and predicted values of MDWS of permanent canines and premolars were compared by paired samples t test in both groups, for both arches.
The accuracy of equations derived from group A was higher than those derived from group B. The difference between actual and predicted values was statistically insignificant in group A and statistically significant in group B.
The results confirm the accuracy of simple linear regression equations derived from a sample of children with no intermaxillary tooth-size discrepancy.
KeywordsBolton ratio Mixed dentition analysis Intermaxillary tooth-size discrepancy
- Bernabe E, Flores-Mir C. Are lower incisors the best predictors for the unerupted canine and premolars sums? An analysis of a Peruvian sample. Angle Orthod. 2005;75:198–203.Google Scholar
- Bolton WA. Disharmony in tooth size and its relation to the analysis and treatment of malocclusion. Angle Orthod. 1958;28:113–30.Google Scholar
- Dahlberg G. Statistical methods for medical and biological students. London: George Allen and Unwin; 1940. p. 122–32.Google Scholar
- Hixon EH, Oldfather RE. Estimation of the sizes of unerupted cuspid and bicuspid teeth. Angle Orthod. 1958;28:236–40.Google Scholar
- Huckaba GW. Arch size analysis and tooth size prediction. Dent Clin North Am. 1964;9:685–97.Google Scholar
- Martinelli FL, Lima EM, Rocha R, Arau´ jo MST. Prediction of lower permanent canine and premolars width by correlation methods. Angle Orthod. 2005;75(3):236–40.Google Scholar
- Moyers RE. Handbook of orthodontics. 4th ed. Chicago: Year Book Medical Publishers; 1958.Google Scholar
- Parades V, Gandia JL, Cibrian RA. New, accurate and fast digital method to predict unerupted tooth size. Angle Orthod. 2006;76:14–9.Google Scholar
- Shah S, Bhaskar V, Venkataraghvan K, et al. Applicability of regression equation using widths of mandibular permanent first molars and incisors as a predictor of widths of mandibular canines and premolars in contemporary Indian population. J Indian Soc Pedod Prev Dent. 2013;31:135–40.CrossRefPubMedGoogle Scholar
- Tahere nik H, Majid S, Mohandes Fateme M, Fard K, Javad M. Predicting the size of unerupted canines and premolars of the maxillary and mandibular quadrants in an Iranian population. J Clin Pediatr Dent. 2007;32(1):43–7.Google Scholar