title: Cross-sectional analysis of the implant-abutment interface.
abstract: The purpose of this study was to develop a technique to evaluate the implant-abutment gap of an external hexagon implant system as a function of radius. Six implants of 3.75 mm in diameter (Conexao Sistema de Protese Ltda, Sao Paulo, Brazil) and their respective abutments were screw connected and torqued to 20 N cm(-1). The implants were mounted in epoxy assuring an implant long-axis position perpendicular to the vertical axis. Each implant was grounded through its thickness parallel to implant long-axis at six different distance interval. Implant-abutment gap distances were recorded along the implant-abutment region for each section. Individual measurements were related to their radial position through trigonometric inferences. A sixth degree polynomial line fit approach determined radial adaptation patterns for each implant. Micrographs along implant sections showed a approximately 300 mum length implant-abutment engagement region. All implants presented communication between external and internal regions through connection gaps and inaccurate implant-abutment alignment. Average gap distances were not significantly different between implants (P > 0.086). Polynomial lines showed implant-abutment gap values below 10 mum from 0 mum to approximately 250 mum of the implant-abutment engagement region. Gap distances significantly increased from approximately 250 mum to the outer radius of the implant-abutment engagement region. The technique described provided a broader scenario of the implant-abutment gap adaptation compared with previous work concerning implant-abutment gap determination, and should be considered for better understanding mechanical aspects or biological effects of implant-abutment adaptation on peri-implant tissues.
authors.affiliation: UNICENP, Curitiba, Parana, Brazil. pgcoelho@nyu.edu
authors.forename: A L
authors.initials: AL
authors.lastname: Coelho
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Dibart
authors.forename: N
authors.initials: N
authors.lastname: DA Silva
authors.forename: P G
authors.initials: PG
authors.lastname: Coelho
mesh_terms: D000044:Dental Abutments; D015921:Dental Implants; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention / Q000379:methods; D019415:Torque
chemical_list: D015921:Dental Implants