title: In vitro evaluation of the removal force of abutments in frictional dental implants.
abstract: The objective of the present work was to determine some force parameters for removal of an abutment from a dental implant in a frictional system (locking taper, 1.23 degrees). Ten implants of the same length (11 mm) and different diameters were selected, along with 10 straight abutments (13 mm length) with different diameters. Abutments were attached to implants without application of force. Fixation of the implant-abutment mount (IA) (repeated 1-5 times) was performed through the impact of a body weight (compression force, tapping) left from a known height. After each group of tappings, IA mounts were coupled with a tensile strength tester. The lowest removal value was found after the first tapping of mount #2 (83 N, implant diameter 3.3 mm/4.5 mm abutment diameter), and the highest removal value happened with mount #8 after the fifth tapping (420 N, 5.0 mm/5.5 mm). The force to remove IA mounts increased with the number of tappings and with the increase in abutment mass. Three activations (tappings) of the abutment were considered necessary to yield optimal stability, demonstrated by the large increase in removal force.
authors.affiliation: Faculty of Dentistry, Positivo University, Curitiba, Paraná, Brazil. jzielak@up.edu.br
authors.forename: João César
authors.initials: JC
authors.lastname: Zielak
authors.forename: Murilo
authors.initials: M
authors.lastname: Rorbacker
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Gomes
authors.forename: Celso
authors.initials: C
authors.lastname: Yamashita
authors.forename: Carla Castiglia
authors.initials: CC
authors.lastname: Gonzaga
authors.forename: Allan Fernando
authors.initials: AF
authors.lastname: Giovanni
mesh_terms: D000044:Dental Abutments; D059605:Dental Implant-Abutment Design; D015921:Dental Implants; D017268:Dental Prosthesis Retention / Q000379:methods; D003799:Dental Stress Analysis; D017276:Friction; D013718:Tensile Strength
chemical_list: D015921:Dental Implants