title: Effect of fit adjustment on CEREC CAD-CAM veneers.
abstract: OBJECTIVE
  To measure and compare the adaptation of CEREC CAD-CAM porcelain veneers with and without fit adjustment.
  
  
  METHODS
  Two groups of porcelain veneers were fabricated using the CEREC CAD-CAM technique for standardized preparations on 10 artificial teeth. Mesial preparation contacts were broken, but distal contacts remained intact. One group was adjusted using a disclosing spray to improve fit, another group made for the same teeth was not adjusted before cementation. The veneers were cemented in a standardized manner to their teeth. The veneers and their attached cement were retrieved, embedded in epoxy resin and sectioned twice to produce eight sections. Each section was measured at three defined points from the external surface inwards.
  
  
  RESULTS
  Three-way ANOVA disclosed that fit adjustment was relatively ineffective (P approximately 0.05), but that measurement section location, measurement point location and their interaction significantly affected fit (P < 0.05). Restoration of the broken proximal contact, or simulated diastema closure did not compromise fit. Incisal margins ranked worst for fit. Surface measurement point locations ranked worse than internal points. The fit of these CEREC CAD-CAM veneers was not substantially different from previously published fit values for conventional porcelain veneers.
authors.affiliation: Department of Restorative Dentistry, University of Southern California, School of Dentistry, Los Angeles 90089-0641, USA.
authors.forename: S N
authors.initials: SN
authors.lastname: White
authors.forename: P S
authors.initials: PS
authors.lastname: Suh
authors.forename: Z
authors.initials: Z
authors.lastname: Yu
authors.forename: R
authors.initials: R
authors.lastname: Johnson
mesh_terms: D000179:Acrylates; D000704:Analysis of Variance; D002484:Cementation / Q000379:methods; D002516:Ceramics; D017076:Computer-Aided Design; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D017267:Dental Prosthesis Design; D003801:Dental Veneers; D005069:Evaluation Studies as Topic; D017755:Prosthesis Fitting / Q000379:methods; D019279:Resin Cements
chemical_list: D000179:Acrylates; D019279:Resin Cements; D003776:Dental Porcelain; C074543:Cerec; C103502:Variolink; C040415:heliobond