Relationship between tooth size and third molar agenesis

ABSTRACT – The hypothesis that third molar agenesis influences crown size of other permanent teeth was tested on a random sample of 300 children in the age group 14–16 years. The individuals were divided into four groups: Group A, full complement of teeth; B, a‐genesis of one or more third molars; C, agenesis of one or more third molars combined with agenesis of other teeth; D, agenesis of teeth other than third molars. Comparison of mesio‐distal crown diameter showed no significant differences between the groups of boys. In girls, differences in mesiodistal crown diameter were lestricted mainly to Groups A and D and thus were not influenced by the third molar. Calculation of asymmetry revealed no significant differences between groups with and without third molars, nor did the anterior ratio differ between these groups.