Effect of two axial wall height preparations on the retentive properties of full crowns using three different cements.
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.
Martins-Pinto
Marcio Guilherme
MG
Department of Prosthodontics, School of Dentistry, Lutheran University of Brazil, Canoas, RS.
Pisani-Proenca
Jatyr
J
Erhardt
Maria Carolina Guilherme
MC
Spielmann
Cezar
C
Del Castillo-Salmeron
Ramon
R
Lopes
Luis Artur Zenni
LA
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
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