Background. As the mental foramen (MF) is an important landmark to facilitate surgical, local anesthetic, and other invasive procedures, the present study was aimed to elucidate its morphological features and morphometric parameters with reference to surrounding landmarks. Material and Method. 105 dry adult human mandibles of unknown sex were observed for position, shape, and number of mental foramina. Their size was measured using a digital vernier caliper and statistically analyzed by mean and standard deviations (SD). Results. In most cases (74.3%), the MF was oval in shape and situated on the longitudinal axis of the 2nd premolar tooth (61% on right side and 59.1% on left side). The mean distance for the right and left sides was measured from various landmarks. Conclusion. Prior knowledge of mental foramen variations helps surgeons in planning surgery in that region to avoid nerve damage and also enable effective mental nerve block anesthesia. 1. Introduction The mental foramen (MF) is situated on the anterolateral aspect of the body of mandible. It gives path to mental nerve and vessels [1–3]. Variations of the mental foramen are often encountered ranging from difference in shape and positions [4–6] to presence of accessory foramen [7] or even complete absence in some cases [8, 9]. Knowledge of its position, shape, and size is important for performing anesthetic block prior to clinical procedures in lower anterior teeth and to preserve integrity of the mental nerve trunk in surgical interventions [10, 11]. As the mental foramen is an important anatomical landmark to facilitate surgical, local anesthetic, and other invasive procedures, the present study is aimed at assessing morphological and morphometric features of mental foramen with reference to surrounding landmarks. 2. Material and Method 105 dry adult human mandible of unknown sex obtained from the Anatomy Department of L.L.R.M. and Subharti Medical College formed the material for study. We observed the position, shape, and number of MF. We measured the distance of MF (in mm) from various landmarks including symphysis menti, alveolar crest, posterior border of the ramus of mandible, and lower border of mandible with digital vernier caliper and calculated the size of mental foramen [2] (Figure 1).AC: distance from alveolar crest to upper margin of mental foramen.BD: distance from lower border of mandible to lower margin of mental foramen.AB: distance from alveolar crest to lower border of mandible.VD: vertical diameter of foramen？？=？？ .WY: distance from symphysis menti to medial margin of
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