ABSTRACT
Sixty-six Thai dry skulls, 34 males and 32 females, were used in measuring the distances from the infraorbital foramen to the mesioincisal point of the central incisor, to the tip of the canine and to the tip of the buccal cusp of the second premolar of the ipsilateral side. The average distances are 5.548 + 0.036, 4.695 + 0.040 and 4.320 + 0.038 cm. respectively. The angles between the occlusal plane and the lines joining the infraorbital foramen to the mesioincisal point of the central incisor, to the tip of the canine and to the tip of the buccal cusp of the second premolar of the ipsilateral side were calculated. The value of the angles are 59.372 + 0.546, 106.538 + 0.569 and 93.0.707 degrees respectively. On each central incisor, an imaginary rectangle was made by using the width of the occlusal edge as the base and the height of the anatomical crown as the height of the rectangle. The average angle between the occlusal edge and the diagonal line is 52.454 + 0.366 degrees. The study of the direction of the opening of the infraorbital foramen revealed that most of the infraorbital foramens of the Thai skulls directed downward and medially.