Abstract
We have reported previously on the descriptive features and the size of the dentition of the Pashtun and Tajik in Afghanistan. The present work concerns an occlusion and incisor inclination. The materials used were 111 upper and lower plaster casts of 74 Pashtuns and 37 Tajiks. The materials of the Japanese used in comparative study were 184 upper and lower plaster casts. On these plaster casts vertical overbite, horizontal overbite (overjet) (fig. 1), sagittal molar relation (fig. 2) and angle of the incisor inclination (fig. 3) were measured. As a rule, the right-side teeth were studied. The results are summarized as follows:
1. Figures for the overbite, overjet and sagittal molar relation are given in table 1. The overbite of the Pashtun is smaller than that of the Tajik or the Japanese. The over jet (from the midpoint of the incisal edge of the upper first incisor to the labial surface of the lower first incisor) of the Pashtun or the Tajik is smaller than that of the Japanese. No significant differ ences between the populations are observed in the sagittal molar relation.
2. The percentage frequency of Angle Class I in the Pashtun or the Tajik is higher than in the Japanese (table 3).
3. Figures for the angle of the incisor inclination are given in table 6. The angle of the upper incisor inclination of the Pashtun or the Tajik is larger than that of the Japanese, but rio significant differences between the populations are observed in the lower incisor inclination.
