The Position of the Mandibular Foramen in the Adult Mandibles of Northeastern Thai

Abstract

Locating the mandibular foramen is important clinically when mandibular nerve block is required.  However, there is still no concrete assesment of the position of the mandibular forament inThai people.  This study was designed to determine the exact position of the mandibular foramen in relation to surrounding bony landmarks as one of the standard references for Thai people.  Forty-nine adult human mandibles of Northeastern Thai were examined to measure the location of the mandibular foramen.  Measurements and observations were based on the following : the distance from the mandibular foramen to the internal oblique ridge (LI), the distance from the mandibular foramen to the anterior border of the mandibular ramus (La) and the distance from the mandibular foramen to the posterior border of the mandibular ramus (LP).  Our study showed that the mean lengths of the LI of the left and right mandibular rami are 13.00 ± 1.82 mm and 13.15 ± 1.87 mm, respectively.  The mean lengths of the LA of the left and right mandibular rami are 20.17 ± 1.86 mm and 20.09 ± 1.77 mm. The mean lengths of the LP of the left and right mandibular rami are 20.74 ± 1.79 mm and 20.46 ± 2.05 mm.  Therefore, the mandibular foramen is located halfway between the anterior and posterior borders of the ramus.  The width of the mandibular ramus is approximately 40 mm. There is no significant difference between the lengths of the left and right mandibular rami measured no matter whether the third molar erupts or not.