title: Repair of non-carious amalgam margin defects.
abstract: This study investigated the microleakage associated with the repair of non-carious amalgam defects using flowable resin composite. Occlusal amalgam preparations were accomplished on 36 non-carious mandibular molars. A standardized 40-micron marginal defect was made by condensing amalgam against a mylar matrix strip. Specimens then underwent a corrosion protocol designed to simulate intraoral corrosion seen with amalgam restorations. The resultant specimens were divided into three treatment groups: 1) No treatment (control); 2) Air abrasion of the amalgam defect surface, acid etching of both amalgam and enamel surfaces, then placement of a flowable composite and 3) Air abrasion of the amalgam defect, application of a fifth-generation dentin bonding agent and placement of the flowable composite. Specimens were thermocycled, sealed with glass ionomer and fingernail polish to within 1 mm of repaired margins, then immersed in basic fuchsin for 24 hours. Specimens were sectioned and microleakage assessed. Results indicated that a flowable resin composite significantly reduced marginal microleakage compared to the control (p < 0.05). There was no difference in microleakage between flowable resin composite repairs done with or without the use of a dentin-bonding agent.
authors.affiliation: USAF Dental Investigation Service, Detachment 1, USAF School of Aerospace Medicine, 310C B Street, Bldg 1H,-Great Lakes, IL 60088, USA.
authors.forename: H W
authors.initials: HW
authors.lastname: Roberts
authors.forename: D G
authors.initials: DG
authors.lastname: Charlton
authors.forename: D F
authors.initials: DF
authors.lastname: Murchison
mesh_terms: D000134:Acid Etching, Dental; D020906:Air Abrasion, Dental; D003188:Composite Resins; D003343:Corrosion; D003723:Dental Amalgam / Q000737:chemistry; D003763:Dental Leakage / Q000209:etiology / Q000517:prevention & control*; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000009:adverse effects*; D017220:Dentin-Bonding Agents; D006801:Humans; D008963:Molar; D018709:Statistics, Nonparametric
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; C423507:PermaFlow; D003723:Dental Amalgam