title: Resin-modified glass-ionomer restorations and in vitro secondary caries formation in coronal enamel.
abstract: OBJECTIVE
  The purpose of this laboratory study was to compare the effects of a resin-modified glass ionomer and a resin composite restorative material on secondary caries formation in coronal enamel.
  
  
  METHODS
  Twelve caries-free molars were sectioned into tooth quarters. Coronal cavities were prepared and then restored with either a resin-modified glass-ionomer material (mesiobuccal and mesiolingual tooth quarters), or a resin composite (distobuccal and distolingual tooth quarters). Caries like lesions were created, and secondary caries was examined by polarized light microscopy following lesion initiation and progression periods.
  
  
  RESULTS
  The resin-modified glass-ionomer specimens had significantly shallower primary surface lesions at both the lesion initiation (35% shallower) and progression (45% shallower) periods than did the resin composite specimens. There were significantly fewer wall lesions (3-fold and 2-fold fewer following lesion initiation and progression, respectively) in the resin-modified glass-ionomer group than in the resin composite group.
  
  
  CONCLUSIONS
  Resin-modified glass-ionomer restorations reduce the susceptibility of unrestored adjacent enamel surfaces and cavosurfaces to a constant cariogenic challenge. The caries resistance imparted to the surface enamel and cavosurface is most likely due to the fluoride release from the resin-modified glass-ionomer material.
authors.affiliation: Department of Pathology, Texas Children's Hospital, USA. mjhicks@texaschildrenshospital.org
authors.forename: M J
authors.initials: MJ
authors.lastname: Hicks
authors.forename: C M
authors.initials: CM
authors.lastname: Flaitz
mesh_terms: D003188:Composite Resins; D003731:Dental Caries / Q000517:prevention & control*; D003793:Dental Restoration, Permanent / Q000379:methods*; D005899:Glass Ionomer Cements; D006801:Humans; D008963:Molar; D012117:Resins, Synthetic; D055502:Secondary Prevention; D012822:Silicon Dioxide; D015040:Zirconium
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements; C081144:Photac-Fil; D012117:Resins, Synthetic; C083568:Z100 composite resin; D012822:Silicon Dioxide; D015040:Zirconium