***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: A community intervention trial was conducted to assess the feasibility of APF gel as a caries-preventive agent in a high-risk group of school children in Bangalore City . The study was conducted in two schools , r and omly selected from a list of schools catering to underprivileged children . These schools were r and omly allocated into experimental and control groups . Children aged 9 - 16 years having three or more incipient or cavitated primary or secondary carious lesions were enrolled in the study . In the experimental group , APF gel was applied and oral health education was provided to both groups at baseline and 6 months . Follow-up examination was performed at 6 and 12 months and the caries status was recorded by an investigator who was blinded to the allocation of intervention . There was no statistically significant difference in DMFT and DMFS values , but a significant difference was seen in incipient carious lesions between the experimental and control groups at 6 and 12 months . These results suggest that biannual APF gel application is an effective preventive measure in reversing incipient carious lesions The aim of this work was to study the effect of a preventive program on the dental plaque and on the  caries incidence in school children . The program comprised weekly supervised self brushing with acidulated phosphate fluoride ( APF ) gel ( pH 5.6 ; concentration : 4520 ppm of ion F- ) . The program involved 240 children of 1st . , 3rd and 5th grade of a primary school in the City of Buenos Aires ( Argentina ) . The population was divided in 2 groups : A ( experimental ) and B ( control ) . Ninety children from both groups ( 45 experimental and 45 control ) were su bmi tted to baseline clinical examination ( DMFT and plaque index ) and microbiological analysis ( total streptococci , St mutans and St. mutans and St. mutans percentage ) . Group A was then su bmi tted to a preventive program which included self brushing with APF gel ( 4520 ppm of ion F- ) . The 90-children sample was monitored after 1 and 2 years of program . Results were statistically processed and they revealed the following : a -- DMFT was significantly greater in the control group than in the experimental group after 1 and 2 years of program ; b -- an 81.43 % reduction in caries increment rate at the end of the 2-years program in the experimental group as compared to the control group ; c -- a rise in the number of colonies of total streptococci and of St. Mutans ; d -- a reduction in the % of St. mutans in the total streptococci flora in the plaque of children in the experimental group ; e -- the presence of St. mutans colonies featuring a rough surface ; f -- the effectiveness of the program in the modifying the profile of the diagnosed dental pathology 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 The primary objective of this clinical trial was to assess the caries-preventive efficacy of 2 years of twice weekly supervised brushing with a self-applied gel containing 12,500 ppm fluoride on schooldays compared with weekly supervised use in children at high caries risk ( with prior caries experience on first permanent molars ) . The secondary objective was to assess efficacy compared with similar children who continued with their usual oral hygiene care . This was a single-centre , single-blind , r and omised , parallel-groups trial comprising two test groups and one untreated control group . 1,075 pupils aged 12–13 years at baseline received a baseline and final examination 2 years later . For all children completing the trial no significant difference was found between groups . For children compliant with study protocol no significant difference was found in the primary outcome ( D1FS caries increment ) , but significant differences were found between the three groups overall in the secondary outcome , D3FT caries increment , with a significant pairwise difference between control and twice per week gel brushing ( 29 % , p = 0.023 D3FT visual + fibre-optic transillumination ) . Analysis of the relationship between number of gel applications and caries showed that children who brushed with the gel at least 60 times over a 2-year period developed significantly fewer carious lesions into dentine than children who followed their usual oral hygiene routine . Some caution is needed as greatest benefit was shown by compliant children . Where schools are co-operative , it is recommended that the gel be used twice a week within a school-based programme over a 2-year period The aim of this study was to evaluate the effect of professional flossing with NaF and SnF2 gels on caries development on approximal tooth surfaces . Two-hundred- and -eighty 13-year-old schoolchildren were divided into 3 groups : ( 1 ) NaF ( n = 97 ) , ( 2 ) SnF2 ( n = 85 ) , and ( 3 ) placebo gel group ( n = 98 ) . The investigation was carried out double-blind . The children were treated 4 times a year for 3 years with 1 % NaF gel , 1 % SnF2 gel , or placebo gel . The treatment was carried out by dental nurses and the time required per visit was approximately 10 min . After 3 years , the mean approximal caries increment , including initial caries lesions , was 2.8 in the NaF , 2.4 in the SnF2 , and 4.0 in the placebo gel group ( P < 0.05 for SnF2 vs placebo ) ; a reduction compared to the placebo of 30 % and 39 % in the NaF and SnF2 groups , respectively . Thus , professional flossing with NaF or SnF2 gel carried out 4 times a year may be considered as an interesting caries-preventing method for large-scale application in schoolchildren The question has been raised whether low-caries children regularly using fluoride toothpaste will benefit from the professional application of additional fluoride gel . To investigate the caries-reducing effect of semi-annually-applied neutral 1 % sodium fluoride gel , we carried out a double-blind r and omized controlled clinical trial ( n = 594 ) in a child population , initially aged 9.5–11.5 years , with baseline caries experience of D3MFS = 0 ( decayed , missing , and filled tooth surfaces of permanent teeth ) . The mean number of tooth surfaces saved from caries development by fluoride gel application after 4 years was 0.2 D3MFS ( SE = 0.17 ) . The preventive fraction ( PF ) showed a mean relative effect of professionally applied fluoride gel of 18 % . The cariostatic effect of the fluoride gel on pits and fissures would have been influenced by the sealant strategy in the study . Professionally applied fluoride gel showed no statistically significant effect on mean D3MFS score in low-caries 9.5- to 11.5-year-olds A clinical field trial was conducted , over a 2-yr period , to evaluate the efficacy of bi-annual APF gel topical applications without previous prophylaxis in reducing dental caries among high-risk children living in non-fluori date d communities . 488 children 6 yr old , presenting at least three cavities on proximal surfaces of their primary teeth , were r and omly assigned to two groups . The experimental group received bi-annual topical APF gel applications and the control group received a placebo . All treatments were given at school without any prior toothcleaning . The APF gel provided a 34.3 % reduction in caries incidence ( P-value = 0.03 ) among the children with 3 - 14 cavities on their primary teeth at the beginning of the study . However , the treatment did not show any efficacy in reducing caries incidence among the higher-risk children having initially more than 14 cavities . These findings suggest that the efficacy of APF gel applications without previous prophylaxis varies according to the individual risk of the subjects and that more comprehensive programs should be targeted to very high-risk children It was the purpose of the study to investigate the caries-reducing effect of semi-annual professional fluoride gel application in a low-caries child population initially aged 4.5–6.5 years during a 4-year follow-up period . In a double-blind r and omised controlled trial ( n = 773 ) the effect of sodium fluoride gel on D < sub>3</sub > MFS and d < sub>3</sub > mfs was compared with a placebo gel .  The mean caries reduction of professionally applied fluoride gel  after 4 years in subjects with baseline caries experience D < sub>3</sub > MFS = 0 as well as d < sub>3</sub > mfs = 0 was 0.08 D < sub>3</sub > MFS ( SE = 0.06 ) and 0.36 d < sub>3</sub > mfs ( SE = 0.22 ) . The prevented fraction for D < sub>3</sub > MFS and d < sub>3</sub > mfs was 26 % ( SE = 16 % ) and 20 % ( SE = 11 % ) , respectively . It was concluded that in the investigated low-caries 4.5- to 6.5-year-olds , fluoride gel treatment showed a statistically significant ( tested one-sided ) caries-inhibiting effect on D < sub>3</sub > MFS , which was considered not clinical ly relevant , and no significant effect on d < sub>3</sub > mfs OBJECTIVES Secondary analyses were performed to study the cariostatic efficacy of semi-annual professional fluoride gel application on incipient carious lesions in low-caries children initially aged 9.5 - 11.5 years . METHODS Double-blind r and omized controlled clinical trial . RESULTS The mean treatment effect of fluoride gel for enamel and dentinal caries lesions after 4 years ' follow-up was 0.92 D(2,3)FS and 0.20 D(3)FS , respectively . When enamel lesions were included in the DFS count ( i.e. D(2,3)FS ) , the preventive fraction ( PF ) showed borderline significance ( 23 % ; P = 0.05 ) . No significant treatment effect of professionally applied fluoride gel  was found for D(2,3)FS and D(3)FS scores of the second molars . The PF for D(2,3)FS of occlusal , approximal , buccal and lingual surfaces and for buccal and palatal pits and fissures differed not significantly . CONCLUSION Professionally applied fluoride gel showed no statistically significant caries-inhibiting effect on both enamel and dentine lesions in the permanent dentition of low-caries children Abstract A clinical trial was conducted in a non-fluori date d water , high-caries community in which school children ( average age = 13.04yr ) were r and omly assigned to one of four groups subjected to two different fluoride procedures . Clinical and radiographic examinations were conducted at baseline , 12 , 24 and 36 months . After 12 months , there was a small but significant rinse effect and a small gel effect which fell short of significance . The effects were additive , and subjects who received both forms of fluoride treatment experienced a 19 per cent reduction in decayed + filled ( DF ) surface increment . The pattern of incremental findings at the end of 24 months was similar to that at 12 months . Both gel and rinse effects were significant and of similar size ; subjects receiving both treatments experienced a 31 per cent reduction in DF surface increment . The incremental findings after 24–36 months 2 yr and 1 yr were similar . The effects were reduced relative to those seen at 24 months ; the gel effect was still statistically significant , but the rinse effect was not . Possible mechanisms underlying the treatment effects include deposition of CaF 2 and fluorapatite , and suppression of microbial flora This study compared caries inhibition in children by an amine fluoride and an acidulated phosphate fluoride when administered in a topically applied gel . In addition , the effects of applying amine fluoride daily and weekly were compared . Four hundred and sixty-eight children , ages 6 to 13 , were r and omly assigned to one of five treatment 
    Output:
    
Subgroup and metaregression analyses suggested no significant association between estimates of D(M)FS prevented fractions and the prespecified trial characteristics .
There is moderate quality evidence of a large caries-inhibiting effect of fluoride gel in the permanent dentition .
There is little information on adverse effects or on acceptability of treatment .