Phase transformation and fracture load of stock and CAD/CAM-customized zirconia abutments after 1 year of clinical functionSchepke, U., Gresnigt, M. M. M., Browne, W. R., Abdolahzadeh, S., Nijkamp, J. & Cune, M. S., Jun-2019, In : CLINICAL ORAL IMPLANTS RESEARCH. 30, 6, p. 559-569 11 p.
Research output: Contribution to journal › Article › Academic › peer-review
Objectives Functional loading and low-temperature degradation may give rise to impaired clinical long-term service of zirconia implant abutments. The aim of this study was to compare the fracture strength (primary outcome measure) and the volume percentage of monoclinic surface zirconia (m-ZrO2) of stock and CAD/CAM-customized zirconia implant abutments that functioned clinically for 1 year with geometrically identical pristine controls in an ex vivo experiment. Material and methods Twenty-three stock (ZirDesign (TM)) and 23 CAD/CAM-customized (Atlantis (TM)) zirconia implant abutments were retrieved after 1 year of clinical service. They were compared with pristine copies with respect to the volume fraction of the monoclinic phase using Raman spectroscopy and their fracture load by means of a single load-to-fracture test. Failure analysis was performed using optical and SEM microscopy. After verification of normal distribution, paired t tests were used for comparison of fracture loads between pristine and clinically aged specimen. All statistical tests employed a level of significance of alpha = 0.05. Results The fracture loads of the stock zirconia abutments were significantly (p <0.05) reduced to 78.8% (SD 29.5%) after one year of clinical function. For the CAD/CAM abutments, no reduction in fracture load was found. No m-ZrO2 volume percentages beyond the detection threshold of 5% were observed in any of the samples. Conclusions After 1 year of clinical service, no difference in fracture strength of the CAD/CAM-customized zirconia implant abutments could be demonstrated, whereas the stock zirconia abutments decreased considerably in fracture strength. No substantial tetragonal-to-monoclinic transformation was observed.
|Number of pages||11|
|Journal||CLINICAL ORAL IMPLANTS RESEARCH|
|Early online date||22-Apr-2019|
|Publication status||Published - Jun-2019|
- biomaterials, clinical research, clinical trials, material sciences, prosthodontics, surface chemistry, TITANIUM IMPLANT ABUTMENTS, ALL-CERAMIC CROWNS, IN-VITRO, BENDING MOMENTS, DIFFERENT ANGULATIONS, INTERNAL CONNECTION, FAILURE MODES, RESISTANCE, STRENGTH, RESTORATIONS