title: Effect of two axial wall height preparations on the retentive properties of full crowns using three different cements.
abstract: This study evaluated how different tooth preparation heights and luting cements affected the retention of metallic full crowns. Tooth preparations were made on 60 extracted maxillary premolars with occluso-cervical heights of 4.0 or 5.0 mm. The nickel chromium (NiCr) metallic crowns in each group were subdivided randomly into three groups (n = 10); the samples in each group were cemented with either a self-adhesive resin cement, a conventional resin cement, or a zinc phosphate cement. Cementation was performed by applying 5.0 kg pressure in 50% relative humidity. Specimens were stored in 100% humidity at 37 degrees C for seven days, at which time they were subjected to a vertical tensile test with a universal testing machine at 0.5 mm/min. Data (Kgf) were analyzed by two-way ANOVA and Tukey's multiple comparisons tests (alpha = 0.01). There was a significant difference in mean force in the height preparations (P < 0.001) and in tensile strength (P < 0.001) among the resin cements. Regardless of the cement used, 5.0 mm high preparations showed significantly higher mean forces than the 4.0 mm high preparations. The self-adhesive resin cement showed significantly higher mean tensile strength than the conventional resin cement; the zinc phosphate cement displayed the lowest retention values. The self-adhesive resin cement displayed retention rates twice that of the zinc phosphate cement.
authors.affiliation: Department of Prosthodontics, School of Dentistry, Lutheran University of Brazil, Canoas, RS.
authors.forename: Marcio Guilherme
authors.initials: MG
authors.lastname: Martins-Pinto
authors.forename: Jatyr
authors.initials: J
authors.lastname: Pisani-Proenca
authors.forename: Maria Carolina Guilherme
authors.initials: MC
authors.lastname: Erhardt
authors.forename: Cezar
authors.initials: C
authors.lastname: Spielmann
authors.forename: Ramon
authors.initials: R
authors.lastname: Del Castillo-Salmeron
authors.forename: Luis Artur Zenni
authors.initials: LA
authors.lastname: Lopes
mesh_terms: D000704:Analysis of Variance; D001641:Bicuspid; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry / Q000627:therapeutic use; D003442:Crowns; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry / Q000627:therapeutic use*; D017268:Dental Prosthesis Retention / Q000379:methods*; D019232:Dental Restoration Failure; D006801:Humans; D008422:Materials Testing; D008437:Maxilla; D009811:Odontometry; D011092:Polyethylene Glycols / Q000737:chemistry / Q000627:therapeutic use; D011109:Polymethacrylic Acids / Q000737:chemistry / Q000627:therapeutic use; D011897:Random Allocation; D019279:Resin Cements / Q000737:chemistry / Q000627:therapeutic use; D018709:Statistics, Nonparametric; D013718:Tensile Strength; D019231:Tooth Preparation, Prosthodontic / Q000379:methods*; D015036:Zinc Phosphate Cement / Q000737:chemistry / Q000627:therapeutic use
chemical_list: D003738:Dental Cements; C534026:HY-Bond Zinc; D011109:Polymethacrylic Acids; C483701:Rely X Unicem; C462240:RelyX ARC; D019279:Resin Cements; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D015036:Zinc Phosphate Cement