Microscopical and chemical surface characterization of CAD/CAM zircona abutments after different cleaning procedures. A qualitative analysis.
OBJECTIVE
To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning.


METHODS
A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non-quantitatively.


RESULTS
All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved.


CONCLUSIONS
The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.
Private Practice, Ludwigshafen, Germany.
Peter
0000-0002-0412-5615
P
Gehrke
Private Practice, Offenburg, Germany.
Astrid
0000-0002-2974-6338
A
Tabellion
Dental Laboratory, Frankfurt, Germany.
Carsten
0000-0003-0753-311X
C
Fischer
Abutment surface; CAD/CAM zirconia abutments; Energy Dyspersive X-ray spectroscopy (EDX); Hybrid abutments; Peri-implant soft tissue response; Spectral-Electron-Microscopy (SEM); Surface contamination; Surface topography; Ultrasonic cleaning