Clarisse Sanon1, Jérôme Chevalier2, Thierry Douillard3, Maria Cattani-Lorente4, Susanne S Scherrer4, Laurent Gremillard3. 1. INSA-Lyon, UMR CNRS 5510 (MATEIS), 7 avenue Jean Capelle, 69621 Villeurbanne Cedex, France; University Lyon 1, Faculty of Odontology, Department of Biomaterials, 11, Rue Guillaume Paradin, 69372 Lyon Cedex 08, France. 2. INSA-Lyon, UMR CNRS 5510 (MATEIS), 7 avenue Jean Capelle, 69621 Villeurbanne Cedex, France; Institut Universitaire de France, 103 bd Saint-Michel, Paris 75005, France. Electronic address: jerome.chevalier@insa-lyon.fr. 3. INSA-Lyon, UMR CNRS 5510 (MATEIS), 7 avenue Jean Capelle, 69621 Villeurbanne Cedex, France. 4. University of Geneva, School of Dental Medicine, Department of Prosthodontics-Biomaterials, 19 rue Barthélémy-Menn, CH 1205 Geneva, Switzerland.
Abstract
OBJECTIVES: Based on the current lack of standards concerning zirconia dental implants, we aim at developing a protocol to validate their functionality and safety prior their clinical use. The protocol is designed to account for the specific brittle nature of ceramics and the specific behavior of zirconia in terms of phase transformation. METHODS: Several types of zirconia dental implants with different surface textures (porous, alveolar, rough) were assessed. The implants were first characterized in their as-received state by Scanning Electron Microscopy (SEM), Focused Ion Beam (FIB), X-Ray Diffraction (XRD). Fracture tests following a method adapted from ISO 14801 were conducted to evaluate their initial mechanical properties. Accelerated aging was performed on the implants, and XRD monoclinic content measured directly at their surface instead of using polished samples as in ISO 13356. The implants were then characterized again after aging. RESULTS: Implants with an alveolar surface presented large defects. The protocol shows that such defects compromise the long-term mechanical properties. Implants with a porous surface exhibited sufficient strength but a significant sensitivity to aging. Even if associated to micro cracking clearly observed by FIB, aging did not decrease mechanical strength of the implants. SIGNIFICANCE: As each dental implant company has its own process, all zirconia implants may behave differently, even if the starting powder is the same. Especially, surface modifications have a large influence on strength and aging resistance, which is not taken into account by the current standards. Protocols adapted from this work could be useful.
OBJECTIVES: Based on the current lack of standards concerning zirconia dental implants, we aim at developing a protocol to validate their functionality and safety prior their clinical use. The protocol is designed to account for the specific brittle nature of ceramics and the specific behavior of zirconia in terms of phase transformation. METHODS: Several types of zirconia dental implants with different surface textures (porous, alveolar, rough) were assessed. The implants were first characterized in their as-received state by Scanning Electron Microscopy (SEM), Focused Ion Beam (FIB), X-Ray Diffraction (XRD). Fracture tests following a method adapted from ISO 14801 were conducted to evaluate their initial mechanical properties. Accelerated aging was performed on the implants, and XRD monoclinic content measured directly at their surface instead of using polished samples as in ISO 13356. The implants were then characterized again after aging. RESULTS: Implants with an alveolar surface presented large defects. The protocol shows that such defects compromise the long-term mechanical properties. Implants with a porous surface exhibited sufficient strength but a significant sensitivity to aging. Even if associated to micro cracking clearly observed by FIB, aging did not decrease mechanical strength of the implants. SIGNIFICANCE: As each dental implant company has its own process, all zirconia implants may behave differently, even if the starting powder is the same. Especially, surface modifications have a large influence on strength and aging resistance, which is not taken into account by the current standards. Protocols adapted from this work could be useful.
Authors: Fernanda H Schünemann; María E Galárraga-Vinueza; Ricardo Magini; Márcio Fredel; Filipe Silva; Júlio C M Souza; Yu Zhang; Bruno Henriques Journal: Mater Sci Eng C Mater Biol Appl Date: 2019-01-16 Impact factor: 7.328
Authors: Tarek A El Awadly; Gang Wu; Mohamed Ayad; Iman A W Radi; Daniel Wismeijer; Hamdy Abo El Fetouh; Reham B Osman Journal: Clin Oral Implants Res Date: 2019-12-19 Impact factor: 5.977