Nerve lateralization (LN), also known as nerve transposition, is often performed alongside the simultaneous transposition of the mental foramen.
INDICATIONS FOR THE PROCEDURE
Nerve lateralization is indicated in cases of extensive resorption of the posterior part of the alveolar ridge of the mandible when implant placement is not possible.
This procedure involves laterally redirecting the trajectory of the inferior alveolar nerve for implant placement.
HOW IS NERVE LATERALIZATION PERFORMED?
After raising the mucoperiosteal flap, the cortex is removed in the projection of the mandibular canal in the desired segment using a round bur.
In one section of the created groove in the cortex, spongiosa is removed to the contents of the canal using a curette. A suitable instrument, such as a “six” or narrow curette, which is introduced into the canal between the neurovascular bundle and the spongiosa, protects the nerve from potential damage caused by the bur. Damage can occur during the final removal of the bone from the lateral wall of the mandibular canal.
The neurovascular bundle is separated from the walls of the mandibular canal using a curette and moved laterally to create space for the safe placement of implants. After implantation, the neurovascular bundle is allowed to passively rest against the implants.
When the transposition of the mental foramen is indicated, a circumferential osteotomy is performed about 1 mm away from the mental foramen.
This way, the cortical part of the bone of the mandible (which forms the mental foramen) is separated from the spongiosa in the form of a ring. This ring is cut in two places and separated from the mental nerve.
In cases where a greater number of implants need to be placed, it may sometimes be indicated to transect the incisive nerve. This nerve innervates the incisors. Once they are extracted, it loses its function, which is often the case for indications for LN.
This procedure increases the flexibility of the aforementioned nerves, thus reducing the risk of complications.
RISKS AND BENEFITS OF NERVE LATERALIZATION
Nerve lateralization falls under higher risk interventions in terms of the function of the alveolar and mental nerve.
However, the advantages of this technique are significantly greater:
