fixed prosthodontics

Objectives: The objective of this systematic review was to identify and compare the effect of different abutment materials on the alveolar bone loss of implant supported superstructure. Methods: An electronic Medline search complemented by manual searching was conducted to identify randomized-controlled clinical trials, and cohort studies providing information on ceramic and metal abutments with a mean follow-up time of at least 6months. Patients had to have been examined clinically at the follow-up visit. Pocket depth, amount of rescission and crestal bone loss were attributed to alveolar bone loss. Results:thirteen clinical studies were selected from an initial yield of 107 titles and data were extracted. Pocket probing depth was recorded in seven studies,at 3-year follow-up, PPD around Zr abutments remained 3.2 mm vs. 3.4 mm at Ti sites. Five studies examined the recession index around Zr and Ti abutments. Reporting mean values from 0 to 0.3 at Zr abutments and 0 to 0.4 at Ti abutments. Mean marginal bone loss around Zr abutments was reported to vary from 0.2-0.4mm to 1.05-1.48mm and 0.3-0.5mm to 0.67-1.43mm at Ti abutments. Conclusion: The information included in this review did not provide evidence for differences of the biological outcomes of ceramic and metal abutments. However, it can be concluded that the direct comparison in the same patient does not give a clear preference for the use of zirconia or titanium as abutment materials in relation to alveolar bone response. A meta-analysis showed statistically significant superiority of Zr abutments over Ti abutments in developing favorable response of Marginal Bone Loss, but with non- statistically significant regarding Pocket Probing Depth (PPD) and Recession Index of soft tissue (RI)