title: Marginal leakage of two newer glass-ionomer-based sealant materials assessed using micro-CT.
abstract: OBJECTIVE
  To test newer glass-ionomer-based materials as sealant materials. One glass-ionomer sealant was light-cured to obtain an early setting reaction. The null-hypothesis tested was: there is no difference in marginal leakage of sealants produced with high-viscosity glass-ionomer, with and without energy supplied, and that of glass-carbomer, in comparison with resin composite sealants in vitro.
  
  
  METHODS
  Materials used were Clinpro, Ketac Molar Easymix and Glass-Carbomer. Sealants were placed in the occlusal surface of 89 molar teeth, thermocycled for 5000 cycles and evaluated using micro-CT for silver nitrate penetration depth at the enamel-sealant interface by two trained evaluators. Data were analysed, using ANOVA and Scheffe's test.
  
  
  RESULTS
  Glass-carbomer sealants showed one or more 'fracture lines' in the material and at the enamel-material interface, filled with a kind of transparent, but not black coloured, material. High-viscosity glass-ionomer sealants with and without energy supplied had statistically significantly lower mean marginal leakage scores than sealants produced by composite resin (p<0.01). No marginal leakage was found in the high-viscosity glass-ionomer group without energy supplied.
  
  
  CONCLUSIONS
  The high-viscosity glass-ionomer (Ketac Molar Easymix) sealants had lower marginal leakage than resin composite sealants, and should be tested in vivo. Glass-carbomer sealants were non-interpretable.
authors.affiliation: Key Laboratory for Oral Biomedical Engineering, School and Hospital of Stomatology, Wuhan University, Luoyu Road 237, 430079 Wuhan, Hubei, PR China.
authors.forename: X
authors.initials: X
authors.lastname: Chen
authors.forename: V
authors.initials: V
authors.lastname: Cuijpers
authors.forename: M
authors.initials: M
authors.lastname: Fan
authors.forename: J E
authors.initials: JE
authors.lastname: Frencken
mesh_terms: D000134:Acid Etching, Dental; D000180:Acrylic Resins / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D055117:Curing Lights, Dental / Q000145:classification; D003743:Dental Enamel / Q000000981:diagnostic imaging*; D003750:Dental Fissures / Q000517:prevention & control; D003763:Dental Leakage / Q000145:classification / Q000000981:diagnostic imaging*; D003764:Dental Materials / Q000737:chemistry; D005898:Glass / Q000737:chemistry; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D010895:Pit and Fissure Sealants / Q000737:chemistry*; D016622:Silver Staining; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014783:Viscosity; D055114:X-Ray Microtomography
chemical_list: D000180:Acrylic Resins; C500418:Clinpro Sealant; D003188:Composite Resins; D003764:Dental Materials; D005899:Glass Ionomer Cements; C515713:Ketac Molar Easymix; D010895:Pit and Fissure Sealants; C479038:carbomer