The relationship between tooth mineralization and early radiographic evidence of the ulnar sesamoid.

The relationship between early radiographic evidence of calcification of the adductor sesamoid of the first metacarpophalangeal joint and the state of maturity of certain teeth was investigated. Data were obtained from the records of one hundred and forty children of Caucasoid origin, comprising ninety-three girls and forty-seven boys. Calcification of the adductor sesamoid was closely related to the completion of root mineralization of the mandibular canine prior to apical closure. No significant sex differences were noted in the state of maturation of the tooth in relation to this particular stage of skeletal development. Correlations among the remaining teeth studied were low, the distribution of calcification stages being widely dispersed with significant sex differences evident. Based on the findings of this study, the completion of root formation of the mandibular canine prior to apical closure may be used as a maturity indicator for the commencement of the circumpubertal growth spurt with a similar degree of confidence as the calcification of the adductor sesamoid of the thumb. It should be noted, however, that racial variations might exist in the relationship between the state of maturity of this tooth and the commencement of mineralization of the sesamoid. Caution should thus be exercised in the application of these findings to other racial groups.