A Study of Certain Prevail Implants Used for the Preservation of Crestal Bone in Short Fixed Bridge Cases.

This prospective, randomized study will evaluate the performance of the Osseotite Certain Prevail implant when compared to that of the non-lateralized version of the implant. Study (null) hypothesis: the crestal bone changes that take place after placement and loading of the Osseotite lateralized implants will be the same as for a similar but non-lateralized Osseotite Certain implant.

Inclusion Criteria: * patients of either sex and any race greater than 18 years of age * patients for whom a decision has already been made to use dental implants for treating an existing condition specifically: A partially edentulous short-span fixed case of less than 4 implants in the maxilla or mandible; the prosthesis may be anterior, posterior, or transitionally anterior-posterior; no cantilevers allowed but one interior crown may be a pontic * patients must be physically able to tolerate conventional surgical and restorative procedures * patients must agree to be evaluated for each study visit, especially the yearly follow-up visits Exclusion Criteria: * patients with active infection or severe inflammation in the areas intended for implant placement * patients with a \>10 cigarette per day smoking habit * patients with uncontrolled diabetes mellitus * patients with metabolic bone disease * patients who have had treatment with therapeutic radiation to the head within the past 12 months * patients in need of allogenic bone grafting a the site of the intended study implant * patients who are pregnant at the screening visit * patients with evidence of severe para-functional habits such as bruxing or clenching * patients with cantilevers and more than one pontic per bridge