title: Amalgam buildups: shear strength and dentin sealing properties.
abstract: The retentive strength and sealing properties of amalgam buildups were compared in vitro in three groups of specimens. All teeth were prepared with flat, nonretentive surfaces. In the first group, the amalgam buildups were retained by four self-threading Minim pins. In the second group, retention was provided by a circumferential slot prepared in the dentin just inside the DEJ. The third group utilized an adhesive resin for retention. Dentin permeability was measured as a hydraulic conductance before and after placement of the amalgam buildups and before and after thermocycling. All methods of retention sealed dentin very well even in the absence of cavity varnish. The 90 degree retentive strength was: pins, 10.3 +/- 0.9 MPa; slots, 4.1 +/- 0.5 MPa; resin, 3.1 +/- 0.8 MPa (mean +/- SEM).
authors.affiliation: Medical College of Georgia, School of Dentistry, Augusta 30912-1129.
authors.forename: E L
authors.initials: EL
authors.lastname: Pashley
authors.forename: R W
authors.initials: RW
authors.lastname: Comer
authors.forename: E E
authors.initials: EE
authors.lastname: Parry
authors.forename: D H
authors.initials: DH
authors.lastname: Pashley
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D003723:Dental Amalgam; D001840:Dental Bonding; D003737:Dental Cavity Preparation; D003772:Dental Pins; D003793:Dental Restoration, Permanent / Q000379:methods*; D003799:Dental Stress Analysis; D003806:Dentin Permeability; D006358:Hot Temperature; D006801:Humans; D008689:Methacrylates
chemical_list: C070606:Amalgambond; D008689:Methacrylates; D003723:Dental Amalgam