Dental arch dimensions and tooth wear in two samples of children in the 1950s and 1990s.

Aim The objective of this study was to compare the degree of tooth wear in posterior deciduous teeth and the dental arch dimensions in the mixed dentition in two modern samples living in the same geographic area and separated by almost 35 years.Methods Dental casts of a group of subjects born between 1953 and 1959 were compared with subjects born between 1990 and 1998. The evaluation of tooth wear scores and measurements for posterior and anterior arch segments, intermolar and intercanine width, and mesiodistal size of incisors were taken. The available anterior space in both arches and the posterior and anterior transverse dimensions were calculated. Groups were compared using a nonparametric test (Mann-Whitney U-test) for independent samples (P<0.05).Results The results show that both boys and girls of the 1990s showed significantly smaller maxillary intermolar width when compared with the 1950s. Posterior transverse interarch discrepancy was significantly minor in girls of the 1990s. The comparison of abrasion showed significant differences between the two groups for all examined teeth which appeared to be more abraded in the 1950s group.Conclusions This association can partially explain the greater risk of developing malocclusions in contemporary children compared with children living 35 years before.