title: Fracture of polycarbonate brackets--a related photoelastic stress analysis.
abstract: In clinical use polycarbonate edgewise bracket designs, patterned on metallic predecessors, have demonstrated slot-wing fracture. A preliminary two-dimensional photoelastic stress investigation is described in which two bracket designs, without angles in the edgewise slot component, are subjected to simulated palatal root torque mechanics.
authors.affiliation: Area Orthodontic Service, Dumfries, Royal Infirmary.
authors.forename: J C
authors.initials: JC
authors.lastname: Aird
authors.forename: D T
authors.initials: DT
authors.lastname: Millett
authors.forename: K
authors.initials: K
authors.lastname: Sharples
mesh_terms: D003799:Dental Stress Analysis; D004548:Elasticity; D004867:Equipment Design; D004868:Equipment Failure; D008962:Models, Theoretical; D009967:Orthodontic Appliances; D011108:Polymers; D013314:Stress, Mechanical
chemical_list: D011108:Polymers; C017902:lexan