title: Is high-viscosity glass-ionomer-cement a successor to amalgam for treating primary molars?
abstract: OBJECTIVE
  To assess and compare the cumulative survival rate of amalgam and atraumatic restorative treatment (ART) restorations in primary molars over 3 years.
  
  
  METHODS
  280 children aged 6-7 years old were enrolled in a cluster randomized controlled clinical trial using a parallel group design covering two treatment groups: conventional restorative treatment with amalgam (CRT) and atraumatic restorative treatment (ART) using a high-viscosity glass-ionomer (HVGIC) Ketac Molar Easymix. Three pedodontists placed 750 restorations (364 amalgam and 386 ART in 126 and 154 children, respectively) which were evaluated at 0.5, 1, 2 and 3 years. The proportional hazard rate regression model with frailty correction, ANOVA and Wald tests, and the Jackknife procedure were applied in analysing the data.
  
  
  RESULTS
  The cumulative survival rates over 3 years for all, single- and multiple-surface CRT/amalgam restorations (72.6%, 93.4%, 64.7%, respectively) were no different from those of comparable ART/HVGIC restorations (66.8%; 90.1% and 56.4%, respectively) (p=0.10). Single-surface restorations had higher survival rates than multiple-surface restorations for the both treatment procedures (p<0.0001). A higher proportion of restorations failed because of mechanical reasons (94.8%) than of secondary caries (5.2%). No difference in reasons for restoration failures between all types of amalgam and ART/HVGIC restorations were observed (p=0.24).
  
  
  CONCLUSIONS
  The high-viscosity glass-ionomer used in this study in conjunction with the ART is a viable option for restoring carious dentin lesions in single surfaces in vital primary molars.
authors.affiliation: Department of Operative Dentistry, School of Health Sciences, University of Brasília, Brazil. Electronic address: leandrohilgert@gmail.com.
authors.forename: Leandro A
authors.initials: LA
authors.lastname: Hilgert
authors.affiliation: Private Practice, Brasília, Brazil.
authors.forename: Rodrigo G
authors.initials: RG
authors.lastname: de Amorim
authors.affiliation: Department of Pediatric Dentistry, School of Health Sciences, University of Brasília, Brazil.
authors.forename: Soraya C
authors.initials: SC
authors.lastname: Leal
authors.affiliation: Department of Global Oral Health, College of Dental Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Mulder
authors.affiliation: Department of Oral Rehabilitation, College of Dental Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Nico H J
authors.initials: NH
authors.lastname: Creugers
authors.affiliation: Department of Global Oral Health, College of Dental Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Jo E
authors.initials: JE
authors.lastname: Frencken
mesh_terms: D002648:Child; D003723:Dental Amalgam; D005899:Glass Ionomer Cements; D006801:Humans; D008963:Molar; D014783:Viscosity
chemical_list: D005899:Glass Ionomer Cements; D003723:Dental Amalgam
keywords: Atraumatic restorative treatment; Dental amalgam; Glass ionomer cement; Primary teeth; Restorations; Restorative care; Survival analysis