title: In vitro standardization of two different removal devices in cemented implant prosthesis.
abstract: OBJECTIVE
  The purpose of this study was to describe the force generated by two different removal devices used to retrieve cemented crowns on implant abutments. The influence of six different operators was evaluated.
  
  
  METHODS
  Three replicated Coronaflex(®) (Kaltenbach & Voigt GmbH, KaVo Dental GmbH) and reverse hammer setups were tested. The experimental setup has employed a screw bearing a diametral hole through which a loop holder passed. The screw was attached to a force transducer (Brüel & Kjaer, type 8201), and the loop holder arm was kept perpendicular to the transducer axis. The results were statistically evaluated with ANOVA.
  
  
  RESULTS
  The operator has resulted to play significant influence with reference to reverse hammer (coefficient of variation 43.3%) rather than with Coronaflex(®) (9.8%). Evaluating every single operator, more variation can still be found by considering each reverse hammer (37.5%) rather than each Coronaflex(®) (8.8%).
  
  
  CONCLUSIONS
  Coronaflex(®) device was found to systematically reach a more repeatable and higher peak amplitude of forces compared with reverse hammer, both by experienced and inexperienced operators.
authors.affiliation: Department of Surgical Science, Dental School, C.I.R University of Turin, Turin, Italy.
authors.forename: Gianmario
authors.initials: G
authors.lastname: Schierano
authors.affiliation: Department of Surgical Science, Dental School, C.I.R University of Turin, Turin, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Manzella
authors.affiliation: Department of Surgical Science, Dental School, C.I.R University of Turin, Turin, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Menicucci
authors.affiliation: Department of Surgical Science, Dental School, C.I.R University of Turin, Turin, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Parrotta
authors.affiliation: Department of Engineering, University of Perugia, Perugia, Italy.
authors.forename: Elisabetta M
authors.initials: EM
authors.lastname: Zanetti
authors.affiliation: Department of Aerospatial and Mechanical Engineering, Politecnico of Torino, Turin, Italy.
authors.forename: Alberto L
authors.initials: AL
authors.lastname: Audenino
mesh_terms: D002484:Cementation; D003442:Crowns; D000044:Dental Abutments; D017268:Dental Prosthesis Retention; D020878:Device Removal / Q000295:instrumentation*; D006801:Humans; D066298:In Vitro Techniques
keywords: Coronaflex®; FDP; force transducer; implant prosthesis; reverse hammer