Estimation of the Crown Widths of Un-erupted Canine and Premolars by Using Vistibulo-oral Crown Dimensions of Per-manent Teeth

Aims: To estimate multiple regression equation on (88) subjects (48 females and 40 males),for predicting the widths of crowns of unerupted canine and premolar for both jaws and both genders. The subjects had normal class I molar relationship with full permanent dentition. Materials and methods: Plaster models of (88) subjects (48 females and 40 males ).Mesiodistal diameter (MMD) and vestibulooral diameter (VOD) of the crown of cental incisor, lateral incisor,canine,premolars and first molar( I1,I2,C both P1 and P2, and M1) on both sides in both jaws were measured. Multiple regression equations and correlation coefficients between the predictors( central incisor,lateral incisor and first molar) and the criteria variables (canine and premolars) were calculated. The data were analyzed by computerized statistical program SPSS. Results: Gradual regression equations were derived on the basis of measurement result ,by using three to five predictors to predict the sums of width of crown of unerupted canine and premolars using separated equations for both jaws and both genders (i.e four multiple regression equations were prepared).The coefficients of multiple correlations regarding gender and jaws ranged between 0.70-0.79.Conclusions: Establish regression equations, which would give satisfactory correlation coefficient regarding the gender and the jaw varied from 0.70-0.79.