Abstract
The aim of the current investigation was to evaluate the fracture resistance of one-piece zirconia oral implants with and without all-ceramic incisor crowns after long-term thermomechanical cycling. A total of 48 implants were evaluated. The groups with crowns (C, 24 samples) and without crowns (N, 24 samples) were subdivided according to the loading protocol, resulting in three groups of 8 samples each: Group “0” was not exposed to cyclic loading, whereas groups “5” and “10” were loaded with 5 and 10 million chewing cycles, respectively. This resulted in 6 different groups: C0/N0, C5/N5 and C10/N10. Subsequently, all 48 implants were statically loaded to fracture and bending moments were calculated. All implants survived the artificial aging. For the static loading the following average bending moments were calculated: C0: 326 Ncm; C5: 339 Ncm; C10: 369 Ncm; N0: 339 Ncm; N5: 398 Ncm and N10: 355 Ncm. To a certain extent, thermomechanical cycling resulted in an increase of fracture resistance which did not prove to be statistically significant. Regarding its fracture resistance, the evaluated ceramic implant system made of Y-TZP seems to be able to resist physiological chewing forces long-term. Restauration with all-ceramic single crowns showed no negative influence on fracture resistance.
Highlights
The clinical long-term results reported for oral implants made of titanium and its biomedical alloys [1,2]have made titanium the “gold standard” material for their fabrication
There have been some concerns that titanium might evoke an unwelcome host reaction but the significance of titanium as a cause of allergic reactions in patients with dental implants remains unproven [5,6,7,8,9]
Aqueous induced dissolution and phase changes of zirconia ceramics resulting in mechanical strength degradation
Summary
The clinical long-term results reported for oral implants made of titanium and its biomedical alloys [1,2]have made titanium the “gold standard” material for their fabrication. Besides its favorable physical and mechanical properties [3], titanium shows a high biocompatibility and a low potential of corrosion [4]. Its predominant biomechanical behavior among biomedical ceramics makes zirconium dioxide to be the ceramic of choice for the fabrication of dental implants [10]. Yttria-stabilized zirconia (Yttria-stabilized tetragonal zirconia polycrystal = Y-TZP) seems to be the favorable core material for the manufacturing of dental implants. This material is characterized by a dense, monocrystalline homogeneity, possesses a low thermal conductivity, a low corrosion potential and a good radiopacity [19]. Aqueous induced dissolution and phase changes of zirconia ceramics resulting in mechanical strength degradation ( known as low-temperature degradation; LTD)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
