title: Direct bonding brackets: unfilled versus unfilled/filled resins.
abstract: The clinical and clinical/laboratorial performance of unfilled/filled and only unfilled resins for direct bonding of orthodontic brackets were evaluated. In the clinical part, brackets were bonded using both techniques in alternate quadrants of eleven patients of the Orthodontic Clinic, State University of Rio de Janeiro. A total of 118 teeth, 59 in each group, were tested and bond failure frequencies were recorded for six months. For the clinical/laboratory part, upper and lower premolars to be extracted for orthodontic reasons, were selected. Thirty-two brackets were bonded in vivo--16 using unfilled/filled and 16 using only unfilled resins--and the teeth were kept in the mouth for two months. After extraction, the teeth were secured in plastic rings and an Universal Instron Machine was used to debond the brackets. No statistically significant differences were observed for clinical failure rates, nor for laboratory debonding strength between the two techniques. Failures occurred preponderantly at the bracket/resin interface, so that most of the resin remained bonded to the enamel surface on both groups.
authors.affiliation: State University of Rio de Janeiro, Brazil.
authors.forename: L C
authors.initials: LC
authors.lastname: Barreto
authors.forename: O
authors.initials: O
authors.lastname: Chevitarese
authors.forename: M A
authors.initials: MA
authors.lastname: Almeida
mesh_terms: D000293:Adolescent; D017438:Bisphenol A-Glycidyl Methacrylate; D016009:Chi-Square Distribution; D002648:Child; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D005260:Female; D006801:Humans; D008297:Male; D008422:Materials Testing; D016910:Orthodontic Brackets; D018709:Statistics, Nonparametric; D013718:Tensile Strength
chemical_list: D003188:Composite Resins; D017438:Bisphenol A-Glycidyl Methacrylate