title: In vivo effect of a resin-modified glass ionomer cement on enamel demineralization around orthodontic brackets.
abstract: Because the risk of dental caries increases with the use of orthodontic appliances and its control cannot depend only on the patient's self-care, this study evaluated the effect of a glass ionomer cement on reducing enamel demineralization around orthodontic brackets. Fourteen orthodontic patients were randomly divided into 2 groups of 7; they received 23 brackets fitted to their premolars, bonded with either Concise (3M Dental Products, St Paul, Minn), a composite resin (control group), or Fuji Ortho LC (GC America, Chicago, Ill), a resin-modified glass ionomer cement (experimental group). The volunteers lived in a city that has fluoridated water, but they did not use fluoridated dentifrices during the study. After 30 days, the teeth were extracted and longitudinally sectioned; in the enamel around the brackets, demineralization was assessed by cross-sectional microhardness. The determinations were made at the bracket edge cementing limits, and at occlusal and cervical points 100 and 200 microm away from them. In all of these positions, indentations were made at depths from 10 to 90 microm from enamel surface. Analysis of variance showed statistically significant effects for position, material, depth, and their interactions (P<.05). The Tukey test showed that the glass ionomer cement was statistically more efficient than the control, reducing enamel demineralization in all analyses (P<.05). The use of glass ionomer cement for bonding can be encouraged because it decreases the development of caries around orthodontic brackets.
authors.affiliation: Department of Dentistry, State University of Maringá, PR, Brazil. rpascotto@uol.com.br
authors.forename: Renata Corrêa
authors.initials: RC
authors.lastname: Pascotto
authors.forename: Maria Fidela de Lima
authors.initials: MF
authors.lastname: Navarro
authors.forename: Leopoldino
authors.initials: L
authors.lastname: Capelozza Filho
authors.forename: Jaime Aparecido
authors.initials: JA
authors.lastname: Cury
mesh_terms: D000180:Acrylic Resins / Q000009:adverse effects / Q000737:chemistry; D000293:Adolescent; D000538:Aluminum Silicates / Q000009:adverse effects / Q000737:chemistry; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000009:adverse effects / Q000737:chemistry; D002648:Child; D001840:Dental Bonding / Q000009:adverse effects / Q000379:methods; D003731:Dental Caries / Q000209:etiology / Q000517:prevention & control*; D003743:Dental Enamel / Q000473:pathology; D005899:Glass Ionomer Cements / Q000009:adverse effects / Q000737:chemistry*; D006801:Humans; D016910:Orthodontic Brackets / Q000009:adverse effects*; D019279:Resin Cements / Q000009:adverse effects / Q000737:chemistry*; D017001:Tooth Demineralization / Q000209:etiology / Q000517:prevention & control*
chemical_list: D000180:Acrylic Resins; D000538:Aluminum Silicates; C095451:Fuji Ortho LC; D005899:Glass Ionomer Cements; D019279:Resin Cements; D017438:Bisphenol A-Glycidyl Methacrylate