title: Implant-Abutment Contact Surfaces and Microgap Measurements of Different Implant Connections Under 3-Dimensional X-Ray Microtomography.
abstract: OBJECTIVE
  The presence of a microgap between implant and abutment could produce a bacterial reservoir which could interfere with the long-term health of the periimplant tissues. The aim of this article was to evaluate, by x-ray 3-dimensional microtomography, implant-abutment contact surfaces and microgaps at the implant-abutment interface in different types of implant-abutment connections.
  
  
  METHODS
  A total of 40 implants were used in this in vitro study. Ten implants presented a screw-retained internal hexagon abutment (group I), 10 had a Morse Cone taper internal connection (group II), 10 another type of Morse Cone taper internal connection (group III), and 10 had a screwed trilobed connection (group IV).
  
  
  RESULTS
  In both types of Morse Cone internal connections, there was no detectable separation at the implant-abutment in the area of the conical connection, and there was an absolute congruity without any microgaps between abutment and implant. No line was visible separating the implant and the abutment. On the contrary, in the screwed abutment implants, numerous gaps and voids were present.
  
  
  CONCLUSIONS
  The results of this study support the hypothesis that different types of implant-abutment joints are responsible for the observed differences in bacterial penetration.
authors.affiliation: *Associate Professor, Department of Medical, Oral and Biotechnological Sciences and CeSI-MeT, University of Chieti-Pescara, Chieti, Italy. †Researcher, Department of Clinical Veterinary Sciences, University of Teramo, Teramo, Italy. ‡Private Practice, Bologna, Italy. §Mechanical Engineering, Department of Technologies and Health, Biomaterials and Contaminants Section, Superior Institute of Health, Rome, Italy. ¶Professor, Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy. ‖Professor, Department of Oral Implantology, Dental Research Division, College Ingá, Cachoeiro de Itapemirim, Brazil. #Research Fellow, Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Scarano
authors.forename: Luca
authors.initials: L
authors.lastname: Valbonetti
authors.forename: Marco
authors.initials: M
authors.lastname: Degidi
authors.forename: Raffaella
authors.initials: R
authors.lastname: Pecci
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
authors.forename: P S
authors.initials: PS
authors.lastname: de Oliveira
authors.forename: Vittoria
authors.initials: V
authors.lastname: Perrotti
mesh_terms: D059605:Dental Implant-Abutment Design / Q000009:adverse effects / Q000379:methods*; D003763:Dental Leakage / Q000209:etiology; D018772:Dental Marginal Adaptation; D066298:In Vitro Techniques; D055114:X-Ray Microtomography