***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: AIM The aim of the study is to evaluate the efficacy of intensive application of sodium fluoride varnish in reducing  caries incidence among children aged 6 to 7 years . MATERIAL S AND METHODS The study was a r and omized controlled trial conducted among 6- to 7-year-old children of Sangamner , Maharashtra , India . Nearly 200 r and omly selected children were r and omized into two groups : Control group and intervention ( varnish ) group . Dental examination to record the caries experiences was conducted at baseline and at 1-year follow-up . The fluoride varnish was applied for three times in a week for a period of 1 year . Mean decayed , missed , and filled teeth ( DMFT ) were compared between and within groups using t-test . RESULTS Out of 200 participants , there were 3 dropouts for control group and 4 for intervention group . Nearly 55 % study participants were males and remaining were females . There was a statistically significant difference between the baseline and follow-up caries levels in varnish group for deciduous dentition . Mean caries reduction in this study was 26 % . CONCLUSION After 1 year of study , we found significant caries reversal in deciduous dentition among the 6- to 7-year-olds after intensive fluoride application . Such a regimen can be advocated to encourage the practitioners and the caregivers alike for early caries prevention . CLINICAL SIGNIFICANCE Intensive fluoride application ( three times a week ) once a year was found to be effective in reducing the incidence of detectable carious lesions and can be advocated to the dental professionals to be incorporated in their routine preventive clinical practice The effects of weekly mouth-rinsings with a 0.5 % sodium fluoride solution were clinical ly and radiologically investigated in 58 children ( age 13.6 years ) from a town with water fluoridation ( Karl-Marx-Stadt , 1.0 + /- 0.1 p.p.m . F ) by means of a longitudinal study on the premolars and canines . As compared to an untreated control group ( 48 subjects ) , a 42 % inhibition of fissure caries increment ( DF/S index ) was stated after 57-fold application ( over 24 months ) The aim was to evaluate a 3-year r and omised controlled trial of school-based fluoride mouth rinsing ( FMR ) on approximal caries development in 13- to 16-year-olds with low to moderate caries risk . The adolescents used F toothpaste at home and underwent prophylactic treatment at yearly check-ups at public dental clinics . Out of 788 r and omly selected 13-year-olds , 622 completed the trial , carried out in 1999–2003 . Supervised by a dental nurse , the subjects rinsed with a 0.2 % NaF solution at different intervals . Group 1 rinsed their teeth on the first three schooldays every semester ; group 2 on the first three and the last three schooldays every semester ; group 3 on three consecutive days once a month during semesters ; group 4 once every fortnight during semesters , and group 5 ( control ) did not rinse .  Radiographic recording of approximal caries was performed . FMR on the three first and the three last schooldays every semester ( group 2 ) had a prevented fraction of 59 % , with approximal enamel lesions as a diagnostic threshold . Corresponding figures for groups 1 , 3 and 4 were 30 , 47 and 41 % , respectively . The control group differed statistically from groups 2–4 for new enamel and dentin lesions and fillings ( p < 0.01 ) . Enamel lesions constituted more than 90 % of the new caries lesions . Caries progression was low for all groups and no significant differences were found between groups . The main conclusion from this r and omised controlled trial is that school-based FMR , as a supplement to the daily use of F toothpaste , reduces caries incidence on approximal surfaces in adolescents with low to moderate caries risk A 32-month study was undertaken to determine the caries inhibitory effect of a weekly rinse for one minute with a solution of 0.2 % NaF on the first permanent molars . Subjects who participated in the study were 295 school children aged from 5 to 13 years who were divided by r and om selection in two groups , test and control who rinsed with either 0.2 % NaF solution or a placebo under double-blind conditions . Reductions in caries increments on first permanent molars ( 20.7 % DMFT and 31.9 % DMFS ) were seen in the test group as compared with the control group . A preventive effect was also seen in all first permanent molars surfaces , being the major protective effect in approximal surfaces ( 52 % reduction ) followed by occlusal ( 36 % ) and bucolingual surfaces ( 16 % ) – The effect of a weekly mouthrinsing with a 0.2 % sodium fluoride solution on the gingiva of children was investigated using a double-blind technique . One hundred and twenty-seven Grade 2 children ( 6–7 years old ) and 126 Grade 6 children ( 12–13 years old ) of Negro and Caucasian background formed the study groups . In each age group , fluoride and placebo subgroups were formed which were balanced as to sex , race and number . Assessment s were made for the presence of gingival inflammation , plaque and calculus on six selected permanent teeth . The results indicated that in neither age group was the degree of gingivitis influenced by the fluoride mouthrinse . Further , no differences between the two age groups in degree of gingivitis and amount of plaque were noted In a municipality near Copenhagen , Denmark , where fortnightly fluoride rinses with 0.2 % neutral sodium fluoride had been performed for more than a decade , 1306 children from kindergarten through 6th grade were stratified by school and grade and r and omly distributed into two groups . One group continued the fluoride rinses , the other group had the fluoride solution replaced with distilled water . Both solutions were slightly flavored . 1083 children completed the 3-yr trial .  Caries was recorded clinical ly by the dentists in the municipal dental service using the diagnostic criteria for the Child Dental Health Services , and on bitewing radiographs by one of the authors applying the criteria developed by GRONDAHL et al. Permanent molars and premolars were included in the study . Clinical ly , caries increment in the two groups was the same with pits and fissures containing 94 % of the DMFS . According to the radiographs , caries progression in the water group was higher than in the fluoride group . This difference was statistically significant for the surfaces erupting during the study ( P less than 0.05 ) OBJECTIVE To measure the effectiveness of fluoride varnish ( FV ) ( Duraflor ) , 5 % sodium fluoride , Pharmascience Inc. , Montréal , QC , Canada ) and caregiver counseling in preventing early childhood caries ( ECC ) in Aboriginal children in a 2-year community-r and omized controlled trial . METHODS Twenty First Nations communities in the Sioux Lookout Zone ( SLZ ) , Northwest Ontario , Canada were r and omized to two study groups . All caregivers received oral health counseling , while children in one group received FV twice per year and the controls received no varnish . A total of 1275 , 6 months to 5-year-old children from the SLZ communities were enrolled . In addition , a convenience sample of 150 primarily non-Aboriginal children of the same age were recruited from the neighboring community of Thunder Bay and used as comparisons . Longitudinal examinations for the dmft/s indices were conducted by calibrated hygienists in 2003 , 2004 and 2005 . RESULTS Aboriginal children living in the SLZ or in Thunder Bay had significantly higher caries prevalence and severity than non-Aboriginal children in Thunder Bay .  FV treatment conferred an 18 % reduction in the 2-year mean ' net ' dmfs increment for Aboriginal children and a 25 % reduction for all children , using cluster analysis to adjust for the intra-cluster correlation among children in the same community . Adjusted odds ratio for caries incidence was 1.96 times higher in the controls than in the FV group ( 95 % CI = 1.08 - 3.56 ; P = 0.027 ) . For those caries-free at baseline , the number ( of children ) needed to treat ( NNT ) equaled 7.4 . CONCLUSIONS Findings support the use of FV at least twice per year , in conjunction with caregiver counseling , to prevent ECC , reduce caries increment and oral health inequalities between young Aboriginal and non-Aboriginal children A 21-month trial of the caries-preventive effect of a 0.2 % NaF mouthrinse included monitoring changes in the concentration of F in normal enamel . Sub sample s of 25 children were r and omly selected from groups receiving either normal dental treatment ( Control group ) ; additional fortnightly professional prophylaxes ( Test group ) ; or prophylaxes plus fortnightly 2-min fluoride rinses ( Test + F group ) . At the start of the trial the sound labial surface of tooth 24 ( occasionally 23 or 22 ) was etched with 2 N HCL and the etchant analysed for F , Ca and phosphate . The contralateral tooth was sample d at the end of the trial . The caries increments ( DFS ) for the three groups over 21 months were Control , 2.88 ; Test , 2.51 and Test + F , 1.77 , the last being significantly less than the others ( P less than 0.05 ) . The average sound enamel surface F concentrations were similar for the three groups at the start and the end of the trial . F parameter calculations showed that all differences were non-significant . Thus this factor could not explain the reduced caries increment due to F mouthrinsing . F biopsies for the purpose of predicting likely clinical effectiveness of neutral 0.2 % NaF mouthrinsing will find little application in public health dentistry Dental caries on approximal tooth surfaces in adolescents is still a problem in Sweden , as well as in many other industrialised countries . The aims of the present thesis were therefore : 1 ) to study whether caries prevalence is underestimated , 2 ) to evaluate the effect of cessation of fluoride mouth rinse ( FMR ) programme in schoolchildren with low caries prevalence , and 3 ) to reconsider the school as an arena for population -based fluoride ( F ) varnish and FMR programmes in order to minimise caries development in 13 - 16-year-olds . Paper I and II showed that the adolescents ' own dentists consistently registered less caries compared to the recordings made by calibrated dentists from outside . Based on 420 16-year-olds at 12 different dental clinics in two neighbouring counties in Sweden , the differences were statistically significant at 10 of the 12 clinics when caries prevalence both was high in 1984 ( Paper I ) and somewhat lower in 1987 and 1990 ( Paper II ) . About 80 % of all approximal caries lesions were enamel lesions and are therefore not reported to the Swedish authorities , as only dentin lesions and fillings are currently included in the official caries data . The basis for Paper III was that many counties in Sweden ab and oned school-based FMR programmes in the mid-late 1980s , as the official caries data revealed low caries prevalence among children . The cessation of FMR for 3 years for a group of 13 - 16-year-old adolescents ( n=60 ) with low caries prevalence did not reveal any statistically significant differences in new caries lesions and fillings or in the progression of existing enamel lesions compared to a group of 13 - 16-year-olds ( n=60 ) who continued to rinse for 3 years . Nor did a supplementary cross-sectional study reveal any differences in caries prevalence among adolescents who had or had not taken part in FMR programmes for the last 3 years . In Papers IV and V , new models for school-based F treatment were evaluated in two 3-year r and omised controlled trials ( RCT studies ) . Fluoride varnish ( Duraphat ) treatment , carried out at school by specially trained dental nurses using a simple mobile unit , among 854 13 - 16-year-olds from low , medium and high caries risk areas showed that the control groups developed more caries than the varnish groups ( Paper IV ) . The largest difference was found in the high-risk area . The prevented fraction ( PF ) with approximal enamel lesions as the diagnostic threshold was 69 % in high , 66 % in medium and 20 % in low risk areas for F varnish applied twice a year at six-month intervals . Supervised school-based FMR among 788 13 - 16-year-olds with low to moderate caries risk ( Paper V ) showed that FMR on the first three and the last three school days during the school term , i.e. 12 rinses/year , had a PF of 59 % . Enamel lesions constituted > 90 % of the new approximal caries lesions in both Papers IV and V. The main conclusions from this thesis are : ( 1 ) that enamel caries lesions on approximal surfaces should be included in epidemiological caries data in order to show true caries prevalence , ( 2 ) that the cessation of weekly FMR for 3 years did not lead to a statistically significant increase in caries incidence in a relatively small group of adolescents with low caries prevalence , and ( 3 ) that the school should be reconsidered as an arena for new models for population - 
    Output:
    
We found no significant association between estimates of D(M)FS prevented fractions and baseline caries severity , background exposure to fluorides , rinsing frequency or fluoride concentration in metaregression analyses .
This review found that supervised regular use of fluoride mouthrinse by children and adolescents is associated with a large reduction in caries increment in permanent teeth .
Most of the evidence evaluated use of fluoride mouthrinse supervised in a school setting , but the findings may be applicable to children in other setting s with supervised or unsupervised rinsing , although the size of the caries-preventive effect is less clear .