Implant deformation and implant–abutment fracture resistance after standardized artificial aging: An in vitro study

Abstract

Background and purpose: Zirconia abutments have been widely adopted in clinical implant practice. The unique mechanical properties of zirconia may significantly affect the long-term prognosis of implant treatments. The purpose of this study was to investigate the influence of abutment material on implant deformation and fracture resistance of internal conical connection implant-abutment complexes of two diameters after standardized artificial aging.Materials and methods: Thirty original abutments (one-piece titanium, one-piece zirconia, zirconia with alloy base) with two diameters (regular, narrow) were connected to internal conical connection implants and subjected to a standardized artificial aging process consisting of thermal cycling and mechanical cyclic loading. Microcomputed tomography (μCT) scans of implant bodies were performed before and after aging.3-dimensional images of implant bodies were generated from the μCT scans and aligned for before and after aging to calculate the volumetric deformation amount.Finally, fracture resistance was measured using a mechanical static loading test for the surviving aged and 30 brand-new specimens.Results: All specimens survived artificial aging. No significant difference in implant deformation was found in the regular groups (p = 0.095). In narrow groups, the onepiece zirconia group showed significantly less deformation (p < 0.0001). For fracture resistance, no significant decrease was observed after aging in any group (p > 0.05).One-piece zirconia abutments showed significantly lower strength than the other two materials for both diameters (p < 0.0001). Conclusions:In the regular diameter system, abutment material had no significant influence on the tested mechanical property degradation after simulated long-term oral use. The mechanical performance of narrow diameter one-piece zirconia abutments differed from the other two materials. For optimal performance, one-piece zirconia abutments should be adopted only in anterior regions.

Single missing molar with wide mesiodistal length restored using a single or double implant-supported crown: A self-controlled case report and 3D finite element analysis

“…Further investigation revealed that utilizing a pair of 3.5 mm implants led to reduced surface strain when compared with only one 5 mm implant. This signified that the double implant technique surpassed the single implant method [57]. In contrast, our findings demonstrated that two 3.5 mm implants in-duced higher levels of cortical bone stress under lateral loading than a single 5.0 mm implant.…”