TY - JOUR TI - Effect of Thermomechanical Loading on the Cementation Interface of Implant-Supported CAD/CAM Crowns Luted to Titanium Abutments AU - Loannidis, A. AU - Gil, A. AU - Hämmerle, C.H.F. AU - Jung, R.E. AU - Zinelis, S. AU - Eliades, G. JO - THE INTERNATIONAL JOURNAL OF PROSTHODONTICS PY - 2020 VL - 33 TODO - 6 SP - 656-662 PB - Quintessence Publishing Co, Inc SN - 0893-7569 TODO - 10.11607/ijp.6709 TODO - titanium, cementation; ceramics; computer aided design; tooth crown, Cementation; Ceramics; Computer-Aided Design; Crowns; Titanium TODO - Purpose: To investigate the effect of aging on the morphology of the interface between monolithic implant crowns and standardized titanium base abutments. Materials and Methods: Four groups of hybrid abutment crowns differing in restorative material (lithium disilicate [LD] or polymer-infiltrated ceramic network [PICN]) and in fabrication procedure of the interfacial zone for luting to a titanium abutment (milled during CAD/ CAM procedure [M] or prefabricated [P]) were formed: LDS-M, LDS-P, PICN-M, and PICN-P (n = 10 each). The morphology of the crown-abutment interface was examined before and after artificial aging using scanning electron microscopy. The total gap length per specimen was measured at both time points, and intergroup (Kruskal-Wallis [KW]) plus pairwise (Wilcoxon Mann-Whitney [WMW]) comparisons were performed (α =. 05). Results: Before aging, statistically significant differences in gap length were identified among groups (KW: P=. 0369) for PICN-P > LDS-P (WMW: P=. 0496) and LDS-M > LDS-P (WMW: P=. 0060). The effect of aging among the groups, expressed as an increment of total gap length, was 50% in LDS-M, 30% in LDS-P, 20% in PICN-M, and 30% in PICN-P. After aging, the statistically significant differences in gap length identified among groups (KW: P=. 0048) were for PICN-P > LDS-P (WMW: P=. 0134); LDS-M > PICN-M (WMW: P=. 0204); PICN-P > PICN-M (WMW: P=. 0486); and LDS-M > LDS-P (P=. 0022). However, comparison of the difference in gap length from before to after aging among the groups was not statistically significant (KW: P =. 3549). Conclusion: The cementation interfaces of CAD/CAM crowns on standardized titanium base abutments demonstrated a high percentage of gaps before and after thermomechanical loading. The composition of the restorative material and the nature of the interface influenced the interfacial gap dimension. Int J Prosthodont 2020;33:656–662. doi: 10.11607/ijp.6709 © 2020. by Quintessence Publishing Co Inc. All rights reserved. ER -