title: Acoustic emission analysis of tooth-composite interfacial debonding.
abstract: This study detected tooth-composite interfacial debonding during composite restoration by means of acoustic emission (AE) analysis and investigated the effects of composite properties and adhesives on AE characteristics. The polymerization shrinkage, peak shrinkage rate, flexural modulus, and shrinkage stress of a methacrylate-based universal hybrid, a flowable, and a silorane-based composite were measured. Class I cavities on 49 extracted premolars were restored with 1 of the 3 composites and 1 of the following adhesives: 2 etch-and-rinse adhesives, 2 self-etch adhesives, and an adhesive for the silorane-based composite. AE analysis was done for 2,000 sec during light-curing. The silorane-based composite exhibited the lowest shrinkage (rate), the longest time to peak shrinkage rate, the lowest shrinkage stress, and the fewest AE events. AE events were detected immediately after the beginning of light-curing in most composite-adhesive combinations, but not until 40 sec after light-curing began for the silorane-based composite. AE events were concentrated at the initial stage of curing in self-etch adhesives compared with etch-and-rinse adhesives. Reducing the shrinkage (rate) of composites resulted in reduced shrinkage stress and less debonding, as evidenced by fewer AE events. AE is an effective technique for monitoring, in real time, the debonding kinetics at the tooth-composite interface.
authors.affiliation: Department of Conservative Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea.
authors.forename: N Y
authors.initials: NY
authors.lastname: Cho
authors.forename: J L
authors.initials: JL
authors.lastname: Ferracane
authors.forename: I B
authors.initials: IB
authors.lastname: Lee
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000162:Acoustics / Q000295:instrumentation; D000268:Adhesiveness; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003737:Dental Cavity Preparation / Q000145:classification; D003738:Dental Cements / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent / Q000145:classification; D017220:Dentin-Bonding Agents / Q000737:chemistry; D055119:Elastic Modulus; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D018583:Pliability; D011092:Polyethylene Glycols / Q000737:chemistry; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D062047:Silorane Resins / Q000737:chemistry; D013016:Sound; D013499:Surface Properties; D013997:Time Factors; D014070:Tooth / Q000648:ultrastructure*
chemical_list: C554641:Adper single bond 2; C438313:Clearfil SE Bond; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C444701:Filtek Z250; D008689:Methacrylates; D011109:Polymethacrylic Acids; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; D062047:Silorane Resins; C544925:filtek P90; C533204:filtek Z350; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate