1988 年 30 巻 3 号 p. 201-207
The lingual surface of the upper first and second molars was metrically investigated. Four parameters were analyzed, i.e., the maximum and minimum lengths of the lingual surface in the mesiodistal direction, their ratio expressed as (min./max.) ×100, and the angle formed by these two lengths, representing cervical constriction. The two lengths were larger in males than in females for both the first and second molars. The ratio was significantly larger for the first molar than for the second molar. It was consequently suggested that cervical constriction was stronger in the first molar than in the second molar. The angle did not show any significant differences either between the sexes or between the two kinds of molar.