Determination of a safety zone for transbuccal trocar placement: an anatomical study

The identification of a safe and accurate technique for facial incisions for transbuccal approaches to the mandibular angle fractures remains a challenge. An alternative method of safely and accurately placing the buccal skin incision is described in this cadaveric study. Thirty-two dissections were performed on 16 bilateral embalmed adult cadaveric heads. In order to identify a safety zone for transbuccal trocar placement, a triangle shaped zone created by three lines was determined. The branches of the facial nerve in this zone were reflected by sharp and blunt dissections. Of 32 sides, marginal mandibular branch was encountered in 1 and marginal mandibular branch and buccal branch of the facial nerve were found in 2 of the predetermined triangle. In 29 of 32 specimens, the marginal mandibular branch was encountered out of the triangle and deep to the platysma muscles. The triangle determined in the present anatomosurgical study presents an easy identifiable and safe zone for trocar placement.