Early Loaded Narrow-diameter Titanium and Titanium-zirconium Implants Retained Mandibular Overdentures

Objectives: The objective of this study was to compare clinically and radiographically the early loading of narrow-diameter implants made of commercially pure titanium and titanium-zirconium alloy that were used to retain mandibular overdentures.
Methods: Twenty completely edentulous patients received two narrow-diameter (3.3 mm) titanium and titanium-zirconium bone level implants (Straumann AG, Basel, Switzerland) in the anterior mandible using the split mouth study design and right-left randomization. The implants were used to retain mandibular overdentures and were early loaded (i.e. 4 weeks) after surgical placement. Standardized clinical and radiographic parameters (survival rate, success rate, probing pocket depth and marginal bone loss) were evaluated at the time of the completion of the prosthetic treatment (baseline) and after 6, 12 and 24 months of functional loading. The data collected were analyzed statistically using t-tests at 95% confidence level.
Results: The survival and success rates for both implant types were 100% after 2-years of functional loading. There were no statistically significant differences (P>0.05) between the values of probing pocket depth in relation to the two implant types over the follow-up period. All implants showed less than 1 mm of marginal bone loss at the end of 1-year of loading. Comparisons between the mean values of marginal bone loss for both implant types at the baseline and the three recall visits were not statistically significant (P>0.05).
Conclusions: It could be concluded that, in 2-years follow-up, narrow-diameter implants made of either commercially pure titanium or titanium-zirconium alloy may be used to retain mandibular overdentures with early loading protocol without any significant differences in terms of evaluated clinical and radiographic parameters.