title: A laboratory study of dimensional changes for three elastomeric impression materials using custom and stock trays.
abstract: Clinical success of fixed prosthodontic procedures is dependent in part upon the dimensional accuracy of elastomeric impression materials and impression procedures. Three elastomeric impression materials were used in custom and stock trays to determine the accuracy of impressions taken from an experimental stainless steel model representing premolar and molar bridge abutment preparations. Horizontal and vertical individual abutment and interabutment dimensions were measured on die stone replicas, and the measurements compared with those obtained from stainless steel master models. The results of this study demonstrate polysulphide is the least accurate impression material for both vertical and horizontal individual abutment dimensions. However, for interabutment horizontal dimensions, no statistical differences were noted between impression material types when using a custom tray. Stock trays produced unreliable results for all the materials tested.
authors.affiliation: Department of Conservative Dental Surgery, Guy's Hospital, London.
authors.forename: J L
authors.initials: JL
authors.lastname: Boulton
authors.forename: J P
authors.initials: JP
authors.lastname: Gage
authors.forename: P F
authors.initials: PF
authors.lastname: Vincent
authors.forename: K E
authors.initials: KE
authors.lastname: Basford
mesh_terms: D000180:Acrylic Resins; D000704:Analysis of Variance; D001641:Bicuspid; D000044:Dental Abutments; D003760:Dental Impression Materials / Q000737:chemistry*; D003761:Dental Impression Technique / Q000295:instrumentation*; D003779:Denture Design; D003829:Denture, Partial; D004867:Equipment Design; D004987:Ethers / Q000737:chemistry; D006801:Humans; D003765:Models, Dental; D008963:Molar; D015203:Reproducibility of Results; D012408:Rubber / Q000737:chemistry*; D012826:Silicone Elastomers / Q000737:chemistry; D013193:Stainless Steel; D013440:Sulfides / Q000737:chemistry; D013499:Surface Properties
chemical_list: D000180:Acrylic Resins; D003760:Dental Impression Materials; D004987:Ethers; C096535:Permadyne Premier; D012826:Silicone Elastomers; D013440:Sulfides; D013193:Stainless Steel; D012408:Rubber; C032915:polysulfide