title: Amalgam bonding: visualization and clinical implications of adhesive displacement during amalgam condensation.
abstract: Resin adhesive was visualized in this in vitro study of amalgam bonding using methylene blue dye incorporated into the resin or by scanning electron microscopy. Class II amalgam cavities were prepared in extracted teeth previously stored in buffered formalin. The preparations were then restored following manufacturers' instructions, but included methylene blue dissolved in ethanol into the adhesive resin mixture. This procedure had little effect on the setting time of the resin. Following condensation and carving, excess resin was incorporated into the body of the restorations as well as onto all adjacent coronal surfaces with significant occlusal and proximal accumulations. Resin also accumulated in significant amounts on the gingival floor of the proximal box and at line angles and retentive grooves within the preparation. In conclusion, radiological studies demonstrated that artifacts produced by resin accumulation at the gingival floor of the box could be mistaken for an open margin or recurrent caries. Other potential clinical consequences of resin residue on tooth surfaces are discussed, including the problem of interproximal ledges and occlusal discrepancies. The incorporation of a radiopaque material in the resin systems should be a universal requirement.
authors.affiliation: College of Dentistry, Division of Operative Dentistry, Dental Clinic, University of Saskatchewan, 105 Wiggins Avenue, Saskatoon, Saskatchewan S7N 5E4, Canada.
authors.forename: D W
authors.initials: DW
authors.lastname: Tyler
authors.forename: J
authors.initials: J
authors.lastname: Thurmeier
mesh_terms: D000269:Adhesives / Q000737:chemistry*; D016477:Artifacts; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry*; D003287:Contrast Media / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry*; D001840:Dental Bonding; D003731:Dental Caries / Q000000981:diagnostic imaging; D003737:Dental Cavity Preparation / Q000145:classification; D003743:Dental Enamel / Q000000981:diagnostic imaging / Q000648:ultrastructure; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008751:Methylene Blue; D008855:Microscopy, Electron, Scanning; D011109:Polymethacrylic Acids / Q000737:chemistry; D011859:Radiography; D019279:Resin Cements / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties
chemical_list: D000269:Adhesives; D004396:Coloring Agents; D003188:Composite Resins; D003287:Contrast Media; C095997:DCR cement; D017220:Dentin-Bonding Agents; D011109:Polymethacrylic Acids; C103500:Prime & Bond; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; D012997:Solvents; D000431:Ethanol; D017438:Bisphenol A-Glycidyl Methacrylate; D003723:Dental Amalgam; D008751:Methylene Blue