A research report submitted to the Faculty of Health Sciences, University of the
Witwatersrand, in partial fulfillment of the requirements for the degree of Master of
Dentistry in the branch of Maxillofacial & Oral Surgery
Johannesburg, 2014INTRODUCTION:
The anterior loop (AL) of the mental nerve is an anatomical structure that should be
considered when placing dental implants in the region of the mental foramen. This study
aimed to evaluate the presence and dimensions of the AL using anatomical dissection of
cadaver specimens.
METHODS:
20 cadaver specimens were dissected bilaterally yielding 40 sides. The position of the mental
foramen was recorded in relation to the lower border of the mandible as well as the
adjacent teeth. Additionally, the mental foramen was probed before accessing the AL in
order to determine the relationship between probing and actual AL length. The AL of the
mental nerve was identified through anatomical dissection and measured.
RESULTS:
The mental foramen was most commonly located between the 1st and 2nd premolars (45%)
followed by the apex of the 2nd premolar (42.5%). The mental foramen ranged from
10,16mm to 16,47mm from the lower border of the mandible (Mean 13,15mm; SD
1,61mm). An AL was found in 22 sides (55%) with a range of 0,52mm to 4,29mm (Mean
1,18mm; SD 1,35mm). Probing versus actual AL length revealed a weak negative correlation
between AL length and probe depth.
CONCLUSIONS:
The study has shown that clinically significant AL lengths can be present and implant
planning must therefore account for these AL
