title: Analysis of Different Impression Techniques and Materials on Multiple Implants Through 3-Dimensional Laser Scanner.
abstract: OBJECTIVE
  The aim of this study was to evaluate the accuracy of 7 different implant impression techniques for full-arch prostheses.
  
  
  METHODS
  A master cast simulating an edentulous arch with 4 implants was used. Seven impression techniques were tested: open tray with polyether Impregum (OTI); open tray with splint-polyether Impregum (OTSI); closed tray with polyether Impregum; open tray with polyether Ramitec; open tray with splint-polyether Ramitec; closed tray with polyether Ramitec (CTR); open tray with impression plaster (OTP). Five impressions of the master cast were taken for each technique using an impression simulator device. Casts were realized based on those impressions (n = 35). Median values of deviation from the master cast were recorded for each cast through a 3-dimensional laser scanner.
  
  
  RESULTS
  Only OTI (P = 0.028) and OTSI (P < 0.001) presented a statistically significant difference compared to the master cast. OTP (P = 0.99) and CTR (P = 0.10) showed median values of deviation close to zero (-0.001 and -0.003 mm, respectively).
  
  
  CONCLUSIONS
  Stiff impression materials (such as plaster or rigid polyether) guarantee greater accuracy in cases of multiple implant impressions of patients with full-arch rehabilitations. Splinting of impression copings with acrylic resin did not improve accuracy.
authors.affiliation: *Lecturer, Department of Fixed and Implant Prosthodontics (DISC), University of Genoa, Genoa, Italy. †Lecturer, Department of Fixed and Implant Prosthodontics (DISC), University of Genoa, Genoa, Italy. ‡Research Fellow, Department of Fixed and Implant Prosthodontics (DISC), University of Genoa, Genoa, Italy. §Assistant Professor, Department of Fixed and Implant Prosthodontics (DISC), University of Genoa, Genoa, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Pera
authors.forename: Paolo
authors.initials: P
authors.lastname: Pesce
authors.forename: Marco
authors.initials: M
authors.lastname: Bevilacqua
authors.forename: Paolo
authors.initials: P
authors.lastname: Setti
authors.forename: Maria
authors.initials: M
authors.lastname: Menini
mesh_terms: D015921:Dental Implants; D003760:Dental Impression Materials / Q000627:therapeutic use*; D003761:Dental Impression Technique; D017267:Dental Prosthesis Design; D006801:Humans; D066298:In Vitro Techniques; D007834:Lasers; D012117:Resins, Synthetic / Q000627:therapeutic use
chemical_list: D015921:Dental Implants; D003760:Dental Impression Materials; C022821:Impregum; D012117:Resins, Synthetic; C056844:Ramitec