RESUMEN
The purpose of this study was to evaluate the correlation between the maxillary and mandibular anterior teeth in a group of Egyptian population with normal occlusion and Angle class I malocclusion and to describe an equation between the maxillary and mandibular anterior teeth which may help in localization of the intermaxillary tooth size discrepancy. The study group consisted of 100 individuals classified into 4 subgroups according to sex and type of occlusion. Using a sharply pointed Bolley gauge the maximum mesiodistal widths of the maxillary [I[1] +I[2] +C] and mandibular [I[1] +I[2] +C+ +bic[1]] were measured on the properly trimmed casts to the nearest 0.1 mm. A high correlation was detected between the sum of mesiodistal width of maxillary and mandibular anterior teeth among all the 4 groups. No statistical significant sex difference was detected in both the normal occlusion group and Angle Class 1 malocclusion group, whereas a significant statistical difference was found between the normal occlusion group and Angle Class I malocclusion in both sexes. The relation between the maxillary and mandibular anterior teeth will be defined as the difference between the anterior mesiodistal widths in the lower jaw [I[1] +I[2] +C +bic[1]] and the tooth widths in a corresponding segment in the upper jaw [I[1] +I[2] +C]. In the normal occlusion, the mean of the difference is 3.2 mm and stripping or reproximation of teeth may be done if the discrepancy is within 2-3 mm