title: Passivity of fit and marginal opening in screw- or cement-retained implant fixed partial denture designs.
abstract: The relationship of stress generation upon placement of cement-retained or screw-retained implant restorations has not been thoroughly investigated. Passivity of fit and marginal discrepancies of screw- and cement-retained implant fixed partial denture (FPD) designs were determined using a photoelastic model of a partially edentulous posterior mandibular arch with 3 screw-type implants. Buccal and lingual marginal openings, measured with a traveling microscope before cementation or screw tightening, revealed no statistical difference in adaptation between designs. Screw tightening caused a reduction in marginal opening (changes significant, P < .05). The opening with the cemented FPDs was similar before and after cementation. Photoelastic evaluation of the FPDs showed that cement-retained FPDs exhibited a more equitable stress distribution than did their screw-retained counterparts.
authors.affiliation: Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, USA. dguichet@ngaseminars.com
authors.forename: D L
authors.initials: DL
authors.lastname: Guichet
authors.forename: A A
authors.initials: AA
authors.lastname: Caputo
authors.forename: H
authors.initials: H
authors.lastname: Choi
authors.forename: J A
authors.initials: JA
authors.lastname: Sorensen
mesh_terms: D002484:Cementation; D000044:Dental Abutments; D003738:Dental Cements / Q000737:chemistry; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D003779:Denture Design; D003830:Denture, Partial, Fixed; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000534:rehabilitation; D008334:Mandible; D008853:Microscopy; D008953:Models, Anatomic; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D003738:Dental Cements