Resin-modified Glass Ionomer Cement(RMGIC) For Fixed Orthodontics (A Systematic Review)

objective:According to the system evaluation methods of the Cochrane Library,all comparisons of resin-modified glass ionomer cement and conventional composite resin are chosen to make rigorous quality evaluation:1.a comparison of the orthodontic brackets' dropout rate between the two adhesives within a certain time;2.the fluoride ions of resin-modified glass ionomer cement releasing;3.antimicrobial effect of resin-modified glass ionomer cement.Methods:The systematic evaluation was conducted strictly under the guide of Cochrane Systematic Review methods,the inclusion and exclusion criterias.We searched the following electronic databases:the Cochrane Oral Health Group Trials Register Database,Cochrane Central Register of Controlled Trials(CENTRAL),MEDLINE via Pubmed(1950-2014),EMBASE(1950-2014),ChineseBiomedicalLiteratureDatabase(CBM),China N ational Knowledge Infrastructure Database(CNKI)and other domestic andinternational databases to obtain the relevant researchs.Meanwhile,we handsearched six kinds of related domestic and international orthodontic journals,conference proceedings and abstracts to obtain the required documents.Two reviewers were independently screened,evaluated and extracted datas.All studies that met the inclusion criterias were selected and attempted to contact the author to obtain source data.Results:Nine trials fulfilling the inclusion criteria from 316 relative studies through comprehensive data search and restrict selection,in which there are seven randomized clinical trials(RCT)and two quasi-randomized clinical trials.But most trials are of poor quality.In expulsion rate of bracket,there is no statistically significant difference between resin-modified glass ionomer cement and resin adhesive when used to bond orthodontic bracket;one study through measuring ARI index in vitro and vivo reaches a conclusion that RMGIC is higher,it means that the bracket is more likely to drop between the tooth and RMGIC which can protect the tooth better.The anti-cariogenicity of RMGIC:two studies compare the abilities of preventing demineralization and remineralization via photos and arrive at that RMGIC is better;two trails through measuring tooth hardness reach that RMGIC has the ability to prevent demineralization;one trail through studying streptococcus finds that there is no statistically significant difference between resin-modified glass ionomer cement and resin adhesive except in 15 days,it prompts that to some degree RMGIC has the ability of bacteriostasis.Conclusions:From this systematic review we can know that there is no statistically significant difference between resin-modified glass ionomer cement and resin adhesive when used to bond orthodontic bracket,to the certain degree,RMGIC can release fluoride ion to prevent enamel demineralization,even making demineralized enamel remineralization,so we support to use it in orthodontics.But there is no reliable evidence from the studies included in this review,future trials in this field should pay more attention to the methodological quality and study design to avoid the problems existed in these trials.