Raíssa Costa Araújo1, Lívia Monteiro Bichara2, Adriana Monteiro de Araujo2, David Normando3. 1. a Resident, Department of Orthodontics, Brazilian Association of Dentistry, Belém, Pará, Brazil. 2. b Graduate student, Department of Orthodontics, School of Dentistry, Federal University of Pará, Belém, Pará, Brazil. 3. c Associate Professor, Department of Orthodontics, School of Dentistry, Federal University of Pará, Belém, Pará, Brazil.
Abstract
OBJECTIVE: To compare the degree of debris and friction of conventional and self-ligating orthodontic brackets before and after clinical use. MATERIALS AND METHODS: Two sets of three conventional and self-ligating brackets were bonded from the first molar to the first premolar in eight individuals, for a total of 16 sets per type of brackets. A passive segment of 0.019 × 0.025-inch stainless steel archwire was inserted into each group of brackets. Frictional force and debris level were evaluated as received and after 8 weeks of intraoral exposure. Two-way analysis of variance and Wilcoxon signed-rank test were applied at P < .05. RESULTS: After the intraoral exposure, there was a significant increase of debris accumulation in both systems of brackets (P < .05). However, the self-ligating brackets showed a higher amount of debris compared with the conventional brackets. The frictional force in conventional brackets was significantly higher when compared with self-ligating brackets before clinical use (P < .001). Clinical exposure for 8 weeks provided a significant increase of friction (P < .001) on both systems. In the self-ligating system, the mean of friction increase was 0.21 N (191%), while 0.52 N (47.2%) was observed for the conventional system. CONCLUSION: Self-ligating and conventional brackets, when exposed to the intraoral environment, showed a significant increase in frictional force during the sliding mechanics. Debris accumulation was higher for the self-ligating system.
RCT Entities:
OBJECTIVE: To compare the degree of debris and friction of conventional and self-ligating orthodontic brackets before and after clinical use. MATERIALS AND METHODS: Two sets of three conventional and self-ligating brackets were bonded from the first molar to the first premolar in eight individuals, for a total of 16 sets per type of brackets. A passive segment of 0.019 × 0.025-inch stainless steel archwire was inserted into each group of brackets. Frictional force and debris level were evaluated as received and after 8 weeks of intraoral exposure. Two-way analysis of variance and Wilcoxon signed-rank test were applied at P < .05. RESULTS: After the intraoral exposure, there was a significant increase of debris accumulation in both systems of brackets (P < .05). However, the self-ligating brackets showed a higher amount of debris compared with the conventional brackets. The frictional force in conventional brackets was significantly higher when compared with self-ligating brackets before clinical use (P < .001). Clinical exposure for 8 weeks provided a significant increase of friction (P < .001) on both systems. In the self-ligating system, the mean of friction increase was 0.21 N (191%), while 0.52 N (47.2%) was observed for the conventional system. CONCLUSION: Self-ligating and conventional brackets, when exposed to the intraoral environment, showed a significant increase in frictional force during the sliding mechanics. Debris accumulation was higher for the self-ligating system.