Dimensional accuracy of ceramic self-ligating brackets and estimates of theoretical torsional play

Abstract

Objective: To ascertain the dimensional accuracies of some commonly used ceramic self-ligation brackets and the amount of torsional play in various bracket-archwire combinations. Materials and Methods: Four types of 0.022-inch slot ceramic self-ligating brackets (upper right central incisor), three types of 0.018-inch ceramic self-ligating brackets (upper right central incisor), and three types of rectangular archwires (0.016 × 0.022-inch beta-Titanium [TMA] (Ormco, Orange, Calif), 0.016 × 0.022-inch stainless steel [SS] (Ortho Technology, Tampa, Fla), and 0.019 × 0.025-inch SS (Ortho Technology)) were measured using a stereomicroscope to determine slot widths and wire cross-sectional dimensions. The mean acquired dimensions of the brackets and wires were applied to an equation devised by Meling to estimate torsional play angle (γ). Results: In all bracket systems, the slot tops were significantly wider than the slot bases (P