The aim of this study was to compare the pain experience among orthodontic patients treated with self-ligating brackets SmartClip® (3M Unitek, Monrovia, California, USA) and conventional brackets Victory series® (3M Unitek, Monrovia, California, USA). We used a controlled clinical trial study design to compare 69 patients treated with self-ligating to 70 patients treated by conventional brackets. The nickel-titanium archwires 0.012-in were engaged after bonding both arches on the first day; and the visual analogue scale (VAS) was used to assess the pain experience of subjects for the first seven treatment days. The pre-treatment dental study models were assessed by the Little’s irregularity index to quantify the groups’ malalignment characteristics. The self-ligating brackets reported lower pain experience than the conventional group on the first five treatment days. However, the sixth day showed 1.75 mm higher visual analogue score than conventional brackets, with almost equal pain level on the seventh day. The group differences throughout the first week were neither clinically nor statistically significant. The pain experiences in both groups decreased steadily from the third treatment day to the end of the first week of treatment. Based on the study findings, the pain experience during initial alignment is not influenced by the brackets’ ligation type. The pain experience tends to decrease steadily from the third treatment day to the end of the first week of treatment irrespective of the bracket type used.
Orthodontic Brackets, Orthodontic Appliances

OBJECTIVE: To evaluate the short-term effect of fangchinoline, an antiinflammatory drug widely used in Asia, on root resorption that is associated with orthodontic tooth movement. METHODS: Twenty-four Wistar rats were randomly divided into 6 groups. Mesial forces of 0, 50, or 100 g were applied to the maxillary first molar of the rats in each group for 14 days by activating nickel-titanium closed-coil springs. One-half of the rats receiving each of these treatments also received injections of 200 microL fangchinoline every 2 days. Finally, movement of the maxillary first molars was measured using digitized radiographs. The molars were extracted and the surfaces of the root resorption craters were recorded using a scanning electron microscope. The distance the molars moved and resorptionarea ratio was measured, and results were analyzed using 2-way ANOVA tests. RESULTS: There were no statistical differences in the distances the first molars moved under 50 or 100 g force, regardless of treatment with fangchinoline. However, the resorption area ratios were significantly smaller in those rats that were treated with both tension and fangchinoline than in those rats treated by tension alone. CONCLUSIONS: Fangchinoline reduced the resorption area ratio in rats and is therefore an important means of alleviating root resorption.
Animals ; Asia ; Benzylisoquinolines ; Electrons ; Gravitation ; Molar ; Rats ; Rats, Wistar ; Root Resorption ; Tooth ; Tooth Movement