Superioralization of the inferior alveolar nerve and roofing for extreme atrophic posterior mandibular ridges with dental implants

摘要

Introduction: Posterior mandibular ridges with extreme atrophy are usually combined with superficial location of the mental nerve and inferior alveolar nerves (IAN) and with a short residual mandibular ridge. As a result, dental implants cannot be placed in conjunction with IAN transposition alone. The aim of this paper is to introduce a new treatment approach to treat those patients. Patients and Methods: Eleven patients with 18 extreme atrophic posterior mandibular ridges characterized by superficial location of the IAN and short residual ridge had been treated during a 4-year period. The treatment approach included superior transposition of the IAN (IAN superioralization), 18 onlay bone block grafts harvested from the calvarial bone, implants placement through the block, and repositioning of the nerve under the onlay graft (IAN roofing). Patients were examined every 2–3 weeks; they received panoramic radiograph immediately after the surgery, at 4 months, at 6 months, and then once a year. Fixed prosthesis was performed after 4–5 months. Results: The donor sites of the bone blocks healed very well. The increase of bone height ranged between 4 and 6 mm at the recipient sites, and 63 long implants were placed (10–13 mm). All the patients were hospitalized 1–3 days. The healing process was uneventful, and the nerve recovery lasted a maximal period of 6 months. The implant success and survival rates were 100%. All patients received fixed prosthesis. The functional outcomes were satisfactory with marked improvement in the quality of life of the patients. The follow-up period was 12–58 months. Conclusions: Superioralization of the IAN and roofing is a fast and predictable option to treat extremely atrophic posterior mandibular ridges with fixed prosthesis supported by dental implants.