title: In vitro microstructural analysis of dental implants subjected to insertion torque and pullout test.
abstract: The change in the implant microstructure during handling may reduce the potential of surface treatment on the osteoinduction and, therefore, on the osseointegration. The aim of this study was to evaluate by energy-dispersive X-ray spectroscopy (EDX) the effect of insertion torque and pullout test on the microstructure of dental implants with different shapes. Four shapes of implants (n=8) were selected: conical with surface treatment (COTS), cylindrical with surface treatment (CTS), cylindrical with double surface treatment (CTSD) and cylindrical with machined surface (CSU). Before and after performing the mechanical tests, the screw surfaces were subjected to analysis of chemical composition by EDX. The results obtained by the microstructural analysis showed presence of three main chemical elements: Ti, C and O. There was a significant change in the concentration of Ti and C. The implant with double surface treatment (CTSD) showed the greatest Ti reduction and the greatest C increase. It may be concluded that the mechanical manipulation may alter the implant surfaces as regards their microstructure. Therefore, surgical planning should take into consideration the choice of surface treatment because the characteristics of the implants may be modified as they are inserted and removed from the bone site.
authors.affiliation: Department of Dental Materials and Prosthetics, School of Dentistry of Ribeirão Preto, USP - University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Mariana Lima da Costa
authors.initials: ML
authors.lastname: Valente
authors.affiliation: Department of Biomaterials, School of Dentistry of Uberaba, UNIUBE - University of Uberaba, Uberaba, MG, Brazil.
authors.forename: Cesar Penazzo
authors.initials: CP
authors.lastname: Lepri
authors.affiliation: Department of Dental Materials and Prosthetics, School of Dentistry of Ribeirão Preto, USP - University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Andréa Candido
authors.initials: AC
authors.lastname: dos Reis
mesh_terms: D015921:Dental Implants; D066298:In Vitro Techniques; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties; D019415:Torque
chemical_list: D015921:Dental Implants