title: A 12 month clinical study of bond failures of recycled versus new stainless steel orthodontic brackets.
abstract: The purpose of this prospective longitudinal randomized study was to compare the clinical performance of recycled brackets with that of new stainless steel brackets (Orthos). Twenty patients treated with fixed appliances were included in the investigation. Using a 'split-mouth' design, the dentition of each patient was divided into four quadrants. In 11 randomly selected patients, the maxillary left and mandibular right quadrants were bonded with recycled brackets, and the remaining quadrants with new stainless steel brackets. In the other nine patients the quadrants were inverted. Three hundred and ten stainless steel brackets were examined: 156 were recycled and the remaining 154 were new. All the brackets were bonded with a self-cured resin-modified glass ionomer (GC Fuji Ortho). The number, cause, and date of bracket failures were recorded over 12 months. Statistical analysis was performed by means of a paired t-test, Kaplan-Meier survival estimates, and the log-rank test. No statistically significant differences were found between: (a) the total bond failure rate of recycled and new stainless steel brackets; (b) the upper and lower arches; (c) the anterior and posterior segments. These findings demonstrate that recycling metallic orthodontic brackets can be of benefit to the profession, both economically and ecologically, as long as the orthodontist is aware of the various aspects of the recycling methods, and that patients are informed about the type of bracket that will be used for their treatment.
authors.affiliation: Department of Orthodontics, Royal Dental College, University of Aarhus, Denmark.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Cacciafesta
authors.forename: Maria Francesca
authors.initials: MF
authors.lastname: Sfondrini
authors.forename: Birte
authors.initials: B
authors.lastname: Melsen
authors.forename: Andrea
authors.initials: A
authors.lastname: Scribante
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000293:Adolescent; D000538:Aluminum Silicates / Q000737:chemistry; D002484:Cementation; D003722:Dental Alloys / Q000737:chemistry*; D001840:Dental Bonding; D004868:Equipment Failure; D017743:Equipment Reuse; D005260:Female; D005500:Follow-Up Studies; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D016555:Matched-Pair Analysis; D008422:Materials Testing; D016910:Orthodontic Brackets; D011446:Prospective Studies; D019279:Resin Cements / Q000737:chemistry; D013193:Stainless Steel / Q000737:chemistry*; D016019:Survival Analysis
chemical_list: D000180:Acrylic Resins; D000538:Aluminum Silicates; D003722:Dental Alloys; C112133:Fuji Ortho; D005899:Glass Ionomer Cements; D019279:Resin Cements; D013193:Stainless Steel