S Touré1, C Vacher, J-Ch Bertrand. 1. Service de Chirurgie Maxillo-faciale et Stomatologie, Hôpital Pitié-Salpêtrière, AP-HP, Paris.
Abstract
INTRODUCTION: the position of the marginal branch of the mandicular nerve is crucial for the surgical approach to the sub-mandibular region. MATERIAL AND METHOD: we performed 54 dissections of 30 fresh cadavers to study the anatomy of this branch. RESULTS: we found a unique marginal branch in 43% of the cases, two branches in 44% and three branches in 13%. In the sub-mandibular region the branch ran lateral to the vessel bundle in 51 cases, was medial to the artery but lateral to the vein in two. In one case, the nerve was lateral to the artery and medial to the vein. The lowest marginal branch was situated 17.5 mm from the inferior border of the mandible and crossed the facial vessels at a point situated 24 mm posteroinferiorly from the mandibular angle. DISCUSSION: our study demonstrated the wide variability of the marginal branch of the mandibular nerve. We found a variable number of branches, different from earlier reports which have generally described two branches in about 50% of the cases. These differences can be explained by the difficulty in recognizing the marginal branch arising from the inferior buccal branch during dissection. The technique of ligaturing the marginal branch of the facial nerve is not reliable in all cases, since the branch sometimes passes lateral to the artery and vein.
INTRODUCTION: the position of the marginal branch of the mandicular nerve is crucial for the surgical approach to the sub-mandibular region. MATERIAL AND METHOD: we performed 54 dissections of 30 fresh cadavers to study the anatomy of this branch. RESULTS: we found a unique marginal branch in 43% of the cases, two branches in 44% and three branches in 13%. In the sub-mandibular region the branch ran lateral to the vessel bundle in 51 cases, was medial to the artery but lateral to the vein in two. In one case, the nerve was lateral to the artery and medial to the vein. The lowest marginal branch was situated 17.5 mm from the inferior border of the mandible and crossed the facial vessels at a point situated 24 mm posteroinferiorly from the mandibular angle. DISCUSSION: our study demonstrated the wide variability of the marginal branch of the mandibular nerve. We found a variable number of branches, different from earlier reports which have generally described two branches in about 50% of the cases. These differences can be explained by the difficulty in recognizing the marginal branch arising from the inferior buccal branch during dissection. The technique of ligaturing the marginal branch of the facial nerve is not reliable in all cases, since the branch sometimes passes lateral to the artery and vein.