Randomized prospective clinical trial of two implant systems for overdenture treatment: a comparison of the 2-year and 5-year results using the clinical implant performance scale.

In a prospective randomized clinical trial, edentulous patients were treated with dental implants and overdentures. The results of treatment with two IMZ implants connected by a Dolderbar, and a transmandibular implant (TMI) were compared. By using the clinical implant performance scale, the clinical and radiographic data were evaluated and compared after a two-year and five-year follow up. After the five-year follow up, significantly less problems and complications were recorded in the IMZ group than in the TMI group (Wilcoxon, P=0.03). When compared to the two-year follow up, there was, however, a gradual increase of scores on the clinical implant performance scale in the IMZ group, while in the TMI group only a slight increase was recorded.