Lateral Approach to the Maxillary Sinus and Mandibular Canal in Severely Atrophied Posterior Alveolar Bone

Purpose: To present a technique to rehabilitate atrophied alveolar ridges in the posterior maxilla and mandible using bone lateral to the maxillary sinus and to the inferior alveolar nerve and to present a retrospective study of the technique. Materials and Methods: Severe resorption of the posterior region of the maxilla and mandible was treated following a conservative approach. Patients who presented this bone crest condition that impeded the placement of implants and had an anatomy that allowed the inferior alveolar nerve or the maxillary sinus to be approached laterally were treated. The bone ridge thickness lateral to the maxillary sinus and the inferior alveolar nerve was measured by computed tomography, and implants with a wedge-shaped design were placed in the available bone. A retrospective review of clinical records of these patients, treated between 1998 and 2012 at the Clinest - Clinical Center of Research in Stomatology, was conducted. The studied variables were surgical and prosthetic complications, the implant survival rate, and the difference between the remaining bone ridge measurement in the ridge center and the implant length placed laterally. Results: Fifty-six patients met the inclusion criteria. These patients received 208 implants according to the aforementioned technique. The mean implant length gain was 6.9 mm, varying from 0.5 to 12 mm. The cumulative survival rate was high for both maxillaries. For the implants placed beside the inferior alveolar nerve, none were lost at 2 years, two were lost at 5 years, and four were lost at 10 years. For the implants placed beside the maxillary sinus, only four implants were lost at 10 years. Nerve injuries and surgical/prosthetic complications occurred but were not significant. Conclusion: The use of available bone alongside the maxillary sinus and inferior alveolar nerve to place implants is a surgical possibility, and a predictable, safe approach, albeit delicate and experience-dependent. Keywords: bone atrophy, inferior alveolar nerve, maxillary sinus, wedge-shaped implants