title: Controlled, prospective, randomized, clinical evaluation of partial ceramic crowns inserted with RelyX Unicem with or without selective enamel etching. 1-year results.
abstract: OBJECTIVE
  To compare the performance of partial ceramic crowns (PCCs) inserted with RelyX Unicem (RXU) either with (RXU+E) or without (RXU) selective enamel etching.
  
  
  METHODS
  34 patients (15 male, 19 female) participated in the investigation, with a total of 68 PCC restorations. In each patient, one PCC was randomly assigned to insertion with RXU, the second PCC was assigned to insertion with RXU+E. The PCCs were CAD/CAM fabricated using the Cerec 3 system. RXU: 25 PCCs were placed in molars, nine in premolars. RXU+E: 26 PCCs were placed in molars, eight in premolars. The restorations were clinically rated using modified United States Public Health Service (USPHS) criteria at baseline, 6 and 12 months after placement. The median patient age was 41 years (24-59 years). The median (25-75%) PBI was 6% (3-9%).
  
  
  RESULTS
  All patients were available for the three recall appointments. One PCC (RXU) debonded after 11 months in situ, one PCC (RXU+E) fractured after 12 months in situ. Both restorations had to be replaced. At the 12 months recall, 66 of 68 controlled restorations were functional without need of replacement. The evaluation using USHPS criteria revealed a significant decrease of alfa ratings over time with respect to criteria marginal adaptation and marginal discoloration. No statistically significant differences between the two luting techniques, RXU and RXU+E, we reobserved during the observation period of 1 year. Within the limitations of the present study, adhesive luting with RXU with or without selective enamel etching can be recommended.
authors.affiliation: Department of Operative Dentistry and Periodontology, University Medical Center Regensburg, Dental School, University of Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg, Germany. Frederike.Schenke@klinik.uni-regensberg.de
authors.forename: Frederike
authors.initials: F
authors.lastname: Schenke
authors.forename: Marianne
authors.initials: M
authors.lastname: Federlin
authors.forename: Karl-Anton
authors.initials: KA
authors.lastname: Hiller
authors.forename: Daniel
authors.initials: D
authors.lastname: Moder
authors.forename: Gottfried
authors.initials: G
authors.lastname: Schmalz
mesh_terms: D000328:Adult; D002484:Cementation / Q000379:methods*; D017076:Computer-Aided Design; D003442:Crowns; D045662:Dental Etching; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019279:Resin Cements; D014075:Tooth Discoloration; D055815:Young Adult
chemical_list: C483701:Rely X Unicem; D019279:Resin Cements; D003776:Dental Porcelain