Objective To evaluate the effectiveness of topical fluoride on prevention of enamel demineralization during the orthodontic treatment in China. Methods The Cochrane Library（Issue 9, 2012), MEDLINE (1996 to 2012.10), EMbase (1974 to 2012.10), CNKI (1994 to 2012.10), VIP (1994 to 2012.10), WanFang data (1998 to 2012.10) and CBM (1978 to 2012.10) are searched for the randomized controlled trials (RCTs) and quasi-Randomized controlled trials (qRCTs) about topical fluoride preventing enamel demineralization during the orthodontic treatment. The bibliographies of the included studies were searched, too. Two reviewers evaluated the quality of the included studies and extracted data critically and independently, and then the extracted data were analyzed using RevMan 5.2 software. Results A total of 20 studies within 19 articles were included, which involved 26 323 teeth. The results of meta-analysis results show that, the rate of enamel demineralization of the fluoride varnish group (8.4%) was lower than that of the control group (16.0%) (OR=0.44, 95%CI 0.33 to 0.59, Plt;0.000 01); the rate of enamel demineralization of the fluoride coating group (8.3%) was lower than that of the control group (17.7%) (OR=0.46, 95%CI 0.35 to 0.60, Plt;0.000 01); the rate of enamel demineralization of the fluoride toothpaste group (9.0%) was lower than that of the control group (14.5%) (OR=0.59, 95%CI 0.49 to 0.71, Plt;0.000 01); the rate of enamel demineralization of the fluoride foam group (11.6%) was lower than that of the control group (18.2%) (OR=0.48, 95%CI 0.24 to 0.96, P=0.04); the rate of enamel demineralization of other groups (12.0%) was lower than that of the control group (21.8%) (OR=0.43, 95%CI 0.30 to 0.60, Plt;0.000 01). Two outcomes were low quality in the GRADE system and the other three are very low quality. Conclusion Current domestic evidence shows that topical fluoride is effective to prevent enamel demineralization during the orthodontic treatment. However, given the low methodological quality of most included studies, this conclusion still needs to be further proved by conducting more strictly-designed, high-quality and large-scale studies.
Objective To assess the clinical effectiveness of vacuum-formed versus Hawley retainers in the period of retention. Methods PubMed, The Cochrane Library, EMbase, CBM, CNKI, VIP, and WanFang Data were searched from the date of their establishment to December 31, 2011, to collect the randomized controlled trials (RCTs) about the clinical effectiveness of vacuum-formed versus Hawley retainers. The quality of the included studies was evaluated by two reviewers independently, and meta-analysis was performed by using RevMan 5.1.4 software. Results Six RCTs including 935 patients were identified. The results of meta-analyses showed significantly fewer changes in irregularity of the maxillary incisors (MD=0.13, 95%CI 0.04 to 0.21) and mandibular incisors (MD=0.29, 95%CI 0.24 to 0.33) in the vacuum-formed group than in the Hawley group. There were no significant differences between the two groups in maxillary intercanine width (MD=?–0.01, 95%CI –0.03 to 0.01), mandibular intercanine width (MD=0.04, 95%CI –0.02 to 0.10), maxillary intermolar width (MD=?–0.01, 95%CI –0.03 to 0.00) and mandibular intermolar width (MD=?–0.02, 95%CI –0.08 to 0.04). The results of qualitative analysis were consistent with the results of meta-analysis and there were no significant differences in overjet and overbite. Conclusion Vacuum-formed retainers are more effective than Hawley retainers at maintaining position of incisors in the period of retention. In other aspects, they are similar. In consideration of the factors such as the limited quality and incomplete measure index of primary studies, RCTs of higher methodological quality are needed.
Objective To analyze the application of rigid intra-oral tooth borne distraction device in dento-alveolar distraction osteogenesis. Methods Six patients who underwent orthodontic treatment for maxillary and/or mandibular canine tooth from January to December 2016 in Hanzhong Central Hospital were collected. The bilateral canine tooth was retracted after the first premolar extraction by using the conventional method, and were distracted by the rigid intra-oral tooth borne distraction device, which was made of stainless steel. The tooth movement distance and time, pain and adverse reaction of patients in the process of orthodontics were investigated. Results The number of orthodontic tooth of each patient was 2–4, and the movement range of canine retraction was 6.5–8.0 mm. The time required for canine tooth moving to the second premolar was 13–17 days, and the canine tooth of all the patients were moved, inclined and buccal expanded after three weeks of enhanced fusion. Two patients felt pain and discomfort, one patient experienced buccal mucosa ulcer, and none of the six patients suffered from dysmasesia, dysphagia, periodontitis or tooth enamel loss. Conclusion As an effective tool for orthodontic treatment, the new rigid intra-oral tooth borne distraction device could accelerate the speed of canine movement, and shorten the orthodontic time with few adverse reactions.