Correspondence
Dr. Varsha Shenoy
Assistant Professor, Department of Anatomy,
Saveetha Medical College, Thandalam,
Chennai- 602105, India.
Phone : 919566275320
E-mail: varsha.shenoy@hotmail.com

Context (Background): Adequate anaesthesia is a prerequisite of most of the dental procedures. Effective pain control in dentistry may be achieved by the local anaesthetic techniques; the most common procedure which is followed being the inferior alveolar nerve block. The Traditional Halstead method is a direct technique in which the inferior alveolar nerve is approached by an intraoral access before it penetrates the mandibular canal. According to previous studies, the failure rate of this procedure was 20%, reaching to even higher percentages in the pulpal anaesthesia. The success of this technique highly depends on the proximity of the needle tip to the mandibular foramen at the time of the anaesthetic injection. For this reason, the technique must be based on the precise anatomical knowledge of the correct location of the mandibular foramen.
Aim: The aim of this study was to locate the mandibular foramen in relation to the borders of the mandibular ramus and also to locate the quadrant of the ramus in which the foramen was located in the vertical and horizontal directions.
Materials and Methods: 50 human mandibles were studied to determine, A. The distance of the mandibular foramen to (a) the anterior border of the ramus (b) the posterior border of the ramus (c) the mandibular incisure (d) the lower border of the ramus. B. The gonial angle and the correlation of the gonial angle to other parameters which were studied and C. To categorize the lingula into various patterns depending on its shape and to measure the bi-lingular distance.
Results: This study revealed that the mandibular foramen was located on the third quadrant antero-posteriorly and at the junction of the second and third quadrant of the ramus supero- inferiorly. There was a negative correlation between the gonial angle and other linear parameters which were studied. The most common type of lingula which was found was of the nodular variety.
Conclusion: Localization of the mandibular foramen is a prerequisite prior to the inferior alveolar nerve block and during any surgical procedures on the mandibular ramus.

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