For the purpose of analyzing the differences in tooth size of deciduous teeth between the present and twenty years ago, we compared the plaster models in deciduous dentition obtained from 71 children (36 males,35 females) who visited our clinic between 1994 and 2000 and those of 68 children (33 males,35 females) who visited us between 1974 and 1980. The correlation between tooth size and interdental spaces was also investigated.
The mesiodistal width of the deciduous tooth crowns of boys showed no significant change during the last twenty years. In contrast, that of girls was larger for every type of tooth. Statistically significant differences were observed in maxillary deciduous central incisors, mandibular deciduous lateral incisors and mandibular deciduous canines. The same tendency was observed in the buccolingal width.
As for girls, the types and prevalence of interdental spaces in the deciduous dentition of the present generation was similar to those of twenty years ago, but for boys, the ratio of the closed type deciduous dentition decreased during the last twenty years.
The size of the tooth crown in deciduous dentition showed a tendency to be larger in the closed type than in the spaced type.