Scanning Electron Microscope Analysis of Cad/Cam Titanium Implant Abutments Versus Gold-Cast Ucla Abutments

Purpose: The objective of the study was to investigate one-piece CAD/CAM abutments made of titanium and gold-cast UCLA-type abutments for contamination, processing marks and microgaps via scanning electron microscope.Material and Methods: Three groups with five identical abutments each were examined with a scanning electron microscope (LEO 1530 VP; Oberkochen, Germany) after cleaning using a steam jet and ethanol. Group 1 included custom CAD/CAM abutments (Atlantis™; Dentsply Implants, Molndal, Sweden). Group 2 included UCLA-type cast bases prior to casting (Astra Tech Cast Design 4.5; Dentsply Implants). Group 3 included the identical cast bases with a cast-on abutment (gold alloy).Results: Contaminants were found on all abutments of group 1, on 3 of 5 samples in group 2 and on 1 of 5 samples in group 3. Processing marks were visible on samples of groups 2 and 3. No microgaps were present in groups 1 and 2. For all group 3 cast-on abutments, large unfilled shrinking cavities with a horizontal extent between <10 and 221 µm and a vertical extent between <10 and 30 µm were found.Conclusions: Both the contaminations and the microgaps of the casted two-piece abutments could be detrimental to the peri-implant hard and soft tissues. Further studies are needed in this regard.