Purpose: The increased use of customized abutments develops with the evolution of CAD/CAM. The importance of fitting accuracy between implant components has been documented. The purpose of the present study was to evaluate the fit of implant-abutment interface for CAD/CAM milled bar over two implants constructed by Poly Ether Ether Ketone (Bio-HPP PEEK), Cobalt Chrome (Co-Cr), Titanium (Ti) and Zirconia using scanning electron microscopy (SEM).
Material and Methods: Two parallel implants with a 14 mm distance from each other were embedded in clear epoxy resin molds. Forty-eight custom milled bars were constructed and were divided equally into four groups: Group (A) Bio-HPP Poly Ether Ether Ketone (PEEK) bar, group (B) Cobalt Chrome (Co-Cr) bar, group (C) Titanium (Ti), and group (D) Zirconia (Zirc) bar. The marginal fit at the implant-abutment interface was scanned and measured under scanning electron microscope.
Results: There was a significant difference between the four studied groups regarding marginal fit the between implant and customized bars. The highest value of micro-gap distance was found in Zirconia bar 17.57 µm ± 1.83 followed by Bio-HPP Poly Ether Ether Ketone bar 9.72 µm ± 3.52. In Titanium bar the micro-gap was 4.02 µm ± 1.19 and the lowest value of micro-gap was recorded in Cobalt Chrome bar 3.22 µm ± 0.75.
Conclusion: CADCAM milled bars fabricated with Chromium Cobalt, Titanium, or PEEK, possesses better internal fit than zirconia milled bars. All the previous milled bars were within the clinically acceptable range of misfit.