External Apical Root Resorption and the Release of Interleukin-1 Beta in the Gingival Crevucular Fluid Treated by a Self-Ligating System

Abstract

The aim of this study was to investigate the amount of external apical root resorption(EARR) and the release of interleukin (IL)-1 beta in the gingival crevicular fluid (GCF) in subjects treated with a low-force low-friction system.Sixty patients were assigned to two groups of thirty patients each: one group received treatment with self-ligating brackets and the other received conventional ligated edgewise brackets. All patients were treated with extraction of the maxillary first premolars. The EARR of the maxillary central incisors was evaluated on the periapical radiographs and cephalograms, taken before and after orthodontic treatment. The GCF was also collected non-invasively from the mesial and distal sides of central incisors using filter paper strips before and after orthodontic treatment. Enzyme-linked immunosorbent assay (ELISA) kits were used to determine the IL-1 beta levels in the GCF samples.A significant difference was found in the amount of EARR between the patients with selfligating brackets and conventional brackets. The mean amount of EARR was significantly lower for self-ligating brackets than the conventional brackets (p<0.05). The GCF levels of IL-1 beta for the patients with the self-ligating brackets application were significantly lower than for those with the conventional brackets (p<0.05).These results show that the mean amount of EARR and the GCF levels of IL-1 beta are significantly lower in patients treated using low-force low-friction appliances than with the conventional brackets. Therefore, self-ligating brackets may be a useful system for reducing inflammation and EARR.