Mental spine the site attatched muscles lingual foramen transmitted the vessels and nerves ana nutrient foramen are located in the internal surface of the mandibles Authors classified the type of the mental spine and observed the numbei diameter direction and location of the lingual foramen the nutrient foramen and the innomi nate foramen in Korean mandibles The results were as followings
I Mental spines were classified SIX types on the basis of the morpholog\Type I sharply sepaiated to right and left was most at the superior mental opines( S2 6 % ) and Type IV bluntly fused in the midline was most at the inferior mental spines( 680 % )
2 The average number of the lingual foramen was one at the superior and inferior lingual foramen
3 Diameter of the superior lingual foramen was 0 46 :t 0 21mm and that of the in ferior lingual foramen was 0 31 :t 0 17mm
4 Mostly the superioi lingual foramen directed superioily( 91. 4 % ) and the inferior lingual foramen directed inferiorly( 62.8 % )
5 The superior lingual foramen was superior to the mental spine( 96 .6 % ) and the
inferior lingual foramen was located inferior to the inferior mental spines( 62 .0 % )
6 The superior lingual foramen was observed at the median surface at the mandibu lar body and located about middle point from the alveolar crest to the inferior border at the edentulous mandible and located at mfenor 2/5 of the dentulous mandible
7 The nutrient foramen was found at the lingual side of the interdental alveolar crest of the anterior teeth of the dentulous mandibles
8 The average number of the nutrient foramen was 2 S and all foramen directed superiorly
9 The innominate foramen was founded in the internal surface of the anterior teeth canine premolar region and the average number of the foramen was three and the average diameter was 0 .36mm