Evaluation of the sizes of deciduous and permanent teeth in patients referring to Isfahan Faculty of Dentistry

Tooth sizes have been reported to be different in different races. Comparison of sizes of primary and permanent teeth, relationship between mesiodistal widths of deciduous and permanent teeth and diagnosis of discrepancies are clinically important. Awareness of the mean sizes of teeth helps predict the space necessary for tooth eruption in space analysis. In this analytical cross-sectional study, the subjects were selected from patients referring to various departments of Faculty of Dentistry, Isfahan University of Medical Sciences, in two groups of 3-5 and 13-18 years of age. Study casts were provided for all the subjects and the mesiodistal widths of the teeth on the left side were measured by a precision caliper. Data was analyzed by ANOVA and independent t-test (α = 0.05). The mean mesiodistal widths of primary and permanent teeth in both jaws were measured. Gender dimorphism had no role as a factor determining mesiodistal width of the crown between boys and girls. The central and lateral maxillary incisors, canines and second mandibular molars were significantly larger in boys compared to girls (p value < 0.05) and maxillary first premolars were significantly greater in girls compared to boys (p value < 0.05). Mesiodistal mean sizes of primary teeth were bigger than those of American whites, but smaller than the Japanese. Like many other studies, mesiodistal mean sizes of teeth in boys were greater compared to girls. Different results in different studies might be attributed to the type of the study (cross-sectional vs long-term), indexes used, races, measuring techniques, the methods employed etc.