Mesiodistal crown diameters of permanent teeth in Jordanians.

Mesiodistal crown diameters were measured from dental casts of the permanent teeth of 198 Jordanians (86 males and 112 females), aged 13.4-19.1 years. The differences in the crown diameters between the right- and left-hand sides of the dental arch were not significant, suggesting that either right- or left-side measurements could be taken to represent the tooth size of the study population. Males had significantly larger teeth than females, ranging from p < 0.05 for the incisors to p < 0.001 for the first molars. In both sexes, the maxillary lateral incisors showed the greatest variability [coefficient of variation (CV) 8.8%] and the first molar the least (CV 5.8%) in mesiodistal diameter. Canines displayed greater sexual dimorphism in crown size than any other tooth class. The cumulative tooth widths of males exceeded those of females by a sum of 3.1 mm in the maxilla and 3.6 mm in the mandible. These differences were statistically significant (p < 0.01). Comparisons of the mesiodistal crown diameters between population groups showed that Jordanians have tooth sizes close to those of Iraqis, but significantly larger than those of Yemenite-Jews, Caucasians and Chinese.