title: A pilot study of the marginal adaptation and surface morphology of glass-cermet cements.
abstract: This study investigated changes in the marginal adaptation and surface morphology of Ketac-Silver and Chelon-Silver glass-current cements over time. Dispersalloy amalgam was used as a control. Contralateral pairs of carious primary molars were restored with the test materials and amalgam. Clinical evaluations were scheduled at 12, 18, and 24 months after placement. Gold-plated replicas of the restorations were observed with scanning electron microscopy. Fractures and cracks in the surface of the Dispersalloy and Chelon-Silver increased the surface roughness; however, the damage was superficial and self-limiting in the Dispersalloy restorations, while in Chelon-Silver the fractures caused the material to break down in layers. A substantial quantity of pores, usually smaller than 50 microns in diameter, were observed throughout the surface of the Chelon-Silver restorations. The pores in the surface of Ketac-Silver were fewer and smaller. The incidence of cavomarginal breakdown increased with time. Chelon-Silver restorations had a higher rate of cavomarginal breakdown than did Ketac-Silver and Dispersalloy restorations up to 18 months. However, there was no statistically significant difference in the marginal adaptation of the three groups at 24 months.
authors.affiliation: University Health Service, University of Hong Kong, Hong Kong.
authors.forename: C H
authors.initials: CH
authors.lastname: Chu
authors.forename: N M
authors.initials: NM
authors.lastname: King
authors.forename: A M
authors.initials: AM
authors.lastname: Lee
authors.forename: C K
authors.initials: CK
authors.lastname: Yiu
authors.forename: S H
authors.initials: SH
authors.lastname: Wei
mesh_terms: D016722:Cermet Cements / Q000737:chemistry*; D002648:Child; D003722:Dental Alloys / Q000737:chemistry; D018772:Dental Marginal Adaptation; D019232:Dental Restoration Failure; D019554:Dental Restoration Wear; D003793:Dental Restoration, Permanent / Q000379:methods; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010865:Pilot Projects; D016062:Porosity; D018030:Silver Compounds / Q000737:chemistry*; D013499:Surface Properties; D013997:Time Factors; D014094:Tooth, Deciduous
chemical_list: D016722:Cermet Cements; D003722:Dental Alloys; D005899:Glass Ionomer Cements; D018030:Silver Compounds; C067445:Chelon Silver; C033470:Dispersalloy