***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVE To compare the effectiveness of annual topical application of silver diamine fluoride ( SDF ) solution , semi-annual topical application of SDF solution , and annual application of a flowable high fluoride-releasing glass ionomer in arresting active dentine caries in primary teeth . METHODS A total of 212 children , aged 3 - 4 years , were r and omly allocated to one of three groups for treatment of carious dentine cavities in their primary teeth :  Gp1-annual application of SDF , Gp2-semi-annual application of SDF , and Gp3-annual application of glass ionomer . Follow-up examinations were carried out every six months to assess whether the treated caries lesions had become arrested . RESULTS After 24 months , 181 ( 85 % ) children remained in the study . The caries arrest rates were 79 % , 91 % and 82 % for Gp1 , Gp2 and Gp3 , respectively ( p=0.007 ) . In the logistic regression model using GEE to adjust for clustering effect , higher caries arrest rates were found in lesions treated in Gp2 ( OR=2.98 , p=0.007 ) , those in anterior teeth ( OR=5.55 , p<0.001 ) , and those in buccal/lingual smooth surfaces ( OR=15.6 , p=0.004 ) . CONCLUSION Annual application of either SDF solution or high fluoride-releasing glass ionomer can arrest active dentine caries . Increasing the frequency of application to every 6 months can increase the caries arrest rate of SDF application . CLINICAL SIGNIFICANCE Arrest of active dentine caries in primary teeth by topical application of SDF solution can be enhanced by increasing the frequency of application from annually to every 6 months , whereas annual paint-on of a flowable glass ionomer can also arrest active dentine caries and may provide a more aesthetic outcome OBJECTIVE To explore whether dentists ' beliefs and attitudes to providing preventive and restorative dental care for young children can form a barrier to the provision of care . BASIC RESEARCH DESIGN The  Barriers to  Childhood Caries  Treatment ( BaCCT ) Question naire , a st and ardised international measure was developed and applied . PARTICIPANTS Through a research consortium , each site was asked to recruit 100 dentists . The sample participating was not intended to be nationally representative . Dentists were mainly r and omly selected and contacted by mail with one or more mailings depending on site . RESULTS 2,333 dentists in 14 countries and 17 sites participated . Factor analysis identified four factors as potential barriers . Two factors were found to be barriers in many sites . First , in most countries , dentists agreed that young children 's coping skills limit their ability to accept dental care . Secondly , dentists with negative personal feelings , for example , that providing care can be stressful and troublesome and that they feel time constrained . Differences in dentists ' beliefs can be partly explained by their work profile , with those treating children often , and those working under systems where they feel they can provide quality care being least likely to identify barriers to providing care for children . CONCLUSIONS The BaCCT Question naire was determined to be a valid psychometric measure . Separately , it was found that health systems do impact on dentists ' ability to deliver preventive and restorative care for children but that these effects vary across countries and further work is needed to determine how best these should be examined Since there is no consensus on the anticaries effectiveness of low-fluoride ( F ) dentifrice , this r and omized clinical trial evaluated its effect in children at different caries activity status . One hundred and twenty 2- to 4-year-old children , half with and half without active caries lesions , were r and omly divided into 2 groups which used 500- or 1,100-µg F/g ( NaF ) dentifrices during 1 year  . Caries progression or regression were evaluated as the number of lesions becoming active/cavities or inactive , respectively . The anticaries effect of the low-F dentifrice was similar to the conventional F dentifrice when used by caries-inactive children . However , in children with active caries lesions the low-F dentifrice was less effective than the 1,100-µg F/g dentifrice in controlling the progression of lesions . The data suggest that the child caries activity may be taken into account to recommend a low-F dentifrice Background Dental caries is a major public health problem in many countries . Since the last territority-wide dental survey of Hong Kong preschool children was conducted in 2001 , a survey to up date the information is necessary . This study aim ed to describe the dental caries experience of preschool children in Hong Kong and factors affecting their dental caries status . Methods A stratified r and om sample of children from seven kindergartens in Hong Kong was surveyed in 2009 . Ethical approval from IRB and parental consent was obtained . Clinical examinations of the children were performed by two calibrated examiners using disposable dental mirrors , an intra-oral LED light and ball-ended periodontal probes . A question naire to investigate possible explanatory factors for caries status was completed by the children ’s parents . Caries experience was recorded using the dmft index . Multifactor-ANOVA was used to study the relationship between dental caries experience , and the background and oral health-related behaviours of the children . Results Seven hundred children ( 53 % boys ) , mean age 5.3 ± 0.7 years were examined .  The mean dmft score of the surveyed children was 2.2 and 51 % of them had no caries experience ( dmft = 0 ) . Most ( > 95 % ) of the decayed teeth were untreated . Statistically significant correlations were found between dental caries experience of the children and their oral health-related habits , family income , parental education level and parental dental knowledge . Conclusions Early childhood dental caries was prevalent among the preschool children in Hong Kong . Their caries experience was associated with their oral health-related behaviours , socio-economic background , and parental education and dental knowledge Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more OBJECTIVES To evaluate the effectiveness of a xylitol pediatric topical oral syrup to reduce the incidence of dental caries among very young children and to evaluate the effect of xylitol in reducing acute otitis media in a subsequent study . DESIGN Double-blind r and omized controlled trial . SETTING Communities in the Republic of the Marshall Isl and s. PARTICIPANTS One hundred eight children aged 9 to 15 months were screened , and 100 were enrolled . Intervention Children were r and omized to receive xylitol topical oral syrup ( administered by their parents ) twice a day ( 2 xylitol [ 4.00-g ] doses and 1 sorbitol dose ) ( Xyl-2 x group ) or thrice per day ( 3 xylitol [ 2.67-g ] doses ) ( Xyl-3x group ) vs a control syrup ( 1 xylitol [ 2.67-g ] dose and 2 sorbitol doses ) ( control group ) . MAIN OUTCOME MEASURES The primary outcome end point of the study was the number of decayed primary teeth . A secondary outcome end point was the incidence of acute otitis media for reporting in a subsequent report . RESULTS Ninety-four children ( mean [ SD ] age , 15.0 [ 2.7 ] months at r and omization ) with at least 1 follow-up examination were included in the intent-to-treat analysis . The mean ( SD ) follow-up period was 10.5 ( 2.2 ) months . Fifteen of 29 of the children in the control group ( 51.7 % ) had tooth decay compared with 13 of 32 children in the Xyl-3x group ( 40.6 % ) and eight of 33 children in the Xyl-2x group ( 24.2 % ) . The mean ( SD ) numbers of decayed teeth were 1.9 ( 2.4 ) in the control group , 1.0 ( 1.4 ) in the Xyl-3x group , and 0.6 ( 1.1 ) in the Xyl-2x group . Compared with the control group , there were significantly fewer decayed teeth in the Xyl-2x group ( relative risk , 0.30 ; 95 % confidence interval , 0.13 - 0.66 ; P = .003 ) and in the Xyl-3x group ( 0.50 ; 0.26 - 0.96 ; P = .04 ) . No statistical difference was noted between the 2 xylitol treatment groups ( P = .22 ) . CONCLUSION Xylitol oral syrup administered topically 2 or 3 times daily at a total daily dose of 8 g was effective in preventing early childhood caries The recording of multiple interval-censored failure times is common in dental research . Modeling multilevel data has been a difficult task . This paper aims to use the Bayesian approach to analyze a set of multilevel clustered interval-censored data from a clinical study to investigate the effectiveness of silver diamine fluoride and sodium fluoride varnish in arresting active dentin caries in Chinese pre-school children . The time to arrest dentin caries on a surface was measured . A three-level r and om-effects Weibull regression model was used . Analysis was performed with WinBUGS . Results revealed a strong positive correlation ( 0.596 ) among the caries lesions ’ arrest times on different surfaces from the same child . The software WinBUGS made the above complicated estimation simple . In conclusion , the annual application of silver diamine fluoride on caries lesions , and caries removal before the application , were found to shorten the arrest time To investigate the effectiveness of topical fluorides in preventing fissure caries , we conducted a r and omized controlled trial with parallel groups . In total , 501 children ( 1,539 molars , 3,078 sites ) , mean age 9.1 years , who had at least one sound permanent first molar with deep fissures or fissures with signs of early caries were recruited . They were r and omly allocated among four groups : ( 1 ) resin sealant , single placement ; ( 2 ) 5 % NaF varnish , semi-annual application ; ( 3 ) 38 % silver diamine fluoride ( SDF ) solution , annual application ; and ( 4 ) placebo control . Follow-up examinations were conducted every 6 months by a masked examiner . After 24 months , 485 children ( 97 % ) were examined . Proportions of pit/fissure sites with dentin caries in the sealant , NaF , SDF , and control groups were 1.6 % , 2.4 % , 2.2 % , and 4.6 % , respectively . A multi-level logistic regression analysis accounting for the effects of data clustering and confounding factors showed that fissures in any of the three treatment groups had significantly lower risks of carious cavity development into dentin than did controls ( p < 0.05 ) . We concluded that placement of resin sealant , semi-annual application of NaF varnish , and annual application of SDF solution are all effective in preventing pit and fissure caries in permanent molars ( Clinical Trials.gov number CT01446107 ) Background There is growing interest in the use of diammine silver fluoride ( DSF ) as a topical agent to treat dentin hypersensitivity and dental caries as gauged by increasing published research from many parts of the world . While DSF has been available in various formulations for many years , most of its pharmacokinetic aspects within the therapeutic concentration range have never been fully characterized . Methods This preliminary study determined the applied doses ( 3 teeth treated ) , maximum serum concentrations , and time to maximum serum concentration for fluoride and silver in 6 adults over 4 h.  Fluoride was determined using the indirect diffusion method with a fluoride selective electrode , and silver was determined using inductively coupled plasma-mass spectrometry . The mean amount of DSF solution applied to the 3 teeth was 7.57 mg ( 6.04 μL ) . Results Over the 4 hour observation period , the mean maximum serum concentrations were 1.86 μmol/L for fluoride and 206 nmol/L for silver . These maximums were reached 3.0 h and 2.5 h for fluoride and silver , respectively . Conclusions Fluoride exposure was below the U.S. Environmental Protection Agency ( EPA ) oral reference dose . Silver exposure exceeded the EPA oral reference dose for cumulative daily exposure over a lifetime , but for occasional use was well below concentrations associated with toxicity . This preliminary study suggests that serum concentrations of fluoride and silver after topical application of DSF should pose little toxicity risk when used in adults . Clinical trials registration NCT01664871 This study compared the ability of two sodium fluoride dentifrices , one containing 5,000 ppm fluoride ( Prevident 5000 Plus ) and the other 1,100 ppm fluoride ( Winterfresh Gel ) , to reverse primary root caries lesions ( PRCLs ) . A total of 201 subjects with at least one PRCL each entered the study and were r and omly allocated to use one of the dentifrices . After 6 months , 186 subjects were included in statistical analyses . At baseline and after 3 and 6 months , the lesions were clinical ly assessed and their electrical resistance measured using an electrical caries monitor . After 3 months , 39 ( 38.2 % ) of the 102 subjects in the 5,000 ppm F– group and 9 ( 10.7 % 
    Output:
    
Conclusions There is limited evidence to support the effectiveness of SDF applications or daily toothbrushing with fluoride toothpaste in arresting or slowing down the progression of active dentin caries in primary teeth in preschool children .