Impact of implant surface topography: a clinical study with a mean functional loading time of 85 months

Objective: Moderately rough, surfaced implants are widely used. Nevertheless data on long-term soft and hard tissue parameters are still conflicting. The purpose of this study was to evaluate peri-implant bone level and soft tissue integration of anodized vs. turned surfaced implants in the anterior mandible after a mean functional loading time of 85 months. Methods: Of 114 edentulous patients invited for follow-up, 41,2% were available for recall. Forty-seven patients with a mean age of 71 +/- 9 years (14 men and 33 women) received 188 dental implants; All patients were edentulous and prosthetic rehabilitation was carried out by a bar-retained overdenture. Radiographic peri-implant bone level was assessed twice at baseline and recall. Clinical examination contained peri-implant sounding (PPD, BoP) and indexing oral hygiene (mPI). Results: From baseline up to 85 months two patients experienced implant loss (four implants), which corresponds to an overall-survival rate of 97.9%. No significant differences were found between implant surfaces concerning the clinical parameters, such as plaque, calculus, bleeding on probing and pocket probing depth. The moderately rough surfaced implants showed significantly less decrease in peri-implant bone level (1.53 +/- 0.25 mm) than turned surfaced implants (2.42 +/- 0.34 mm) (P = 0.036). The interaction between the position of the implant and surface topography (P = 0.037) as well as the site at the implant (P = 0.004) had a significant influence on bone level changes. Conclusion: Both surface topographies with bar-supported overdentures have excellent long-term clinical outcomes. Moreover, a moderately roughened, anodized surface has beneficial effects in the anterior lower jaw.