title: Enamel abrasion from ceramic orthodontic brackets under an artificial oral environment.
abstract: The purpose of this investigation was to examine the potential enamel abrasion on contact with stainless steel and various ceramic orthodontic brackets under a simulated oral environment. Three groups of eight lower premolar ceramic brackets and one group of eight stainless steel brackets were used from four different manufacturers. An upper premolar was brought in contact with the bracket bonded to a lower premolar tooth and subjected to a lateral excursion type of movement by the artificial oral environment. A constant load of approximately 2 lb was used for the masticatory force. The rate of chewing was 1 cycle/sec. The teeth were subjected to 15, 60, and 100 masticatory cycles. The before-and-after occlusal surfaces of the upper premolars were compared by means of a computerized profiling system and the enamel volume loss was calculated. Qualitative changes, such as rate of enamel wear, were examined visually by means of computer graphics and the scanning electron microscope. Abrasion scores (mean +/- SD) in mm3 were 0.015 +/- 0.01 from the metal brackets and 0.135 +/- 0.103, 0.255 +/- 0.242, and 0.581 +/- 0.524 from the three ceramic bracket groups. The abrasion scores were significantly different at p less than 0.05. Ceramic brackets caused significantly greater enamel abrasion than stainless steel brackets. Artificial mouth in vitro testing gave a good indication of clinical performance of orthodontic brackets.
authors.affiliation: Department of Orthodontics, School of Dentistry, University of Minnesota, Minn.
authors.forename: A D
authors.initials: AD
authors.lastname: Viazis
authors.forename: R
authors.initials: R
authors.lastname: DeLong
authors.forename: R R
authors.initials: RR
authors.lastname: Bevis
authors.forename: J D
authors.initials: JD
authors.lastname: Rudney
authors.forename: M R
authors.initials: MR
authors.lastname: Pintado
mesh_terms: D000535:Aluminum / Q000009:adverse effects*; D000537:Aluminum Oxide / Q000009:adverse effects*; D000704:Analysis of Variance; D003196:Computer Graphics; D003743:Dental Enamel / Q000293:injuries; D003799:Dental Stress Analysis; D006801:Humans; D008954:Models, Biological; D009967:Orthodontic Appliances / Q000009:adverse effects*; D013193:Stainless Steel / Q000009:adverse effects*; D014072:Tooth Abrasion / Q000209:etiology*
chemical_list: D013193:Stainless Steel; D000535:Aluminum; D000537:Aluminum Oxide