***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*** 
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    Input: OBJECTIVES The aim of the present study was to investigate the caries-preventive effect of sealants produced with a high-viscosity glass-ionomer with an elevated powder-liquid ratio ( ART ) , of having energy added to this glass-ionomer , and that of glass-carbomer , in comparison to that of resin composite sealants . METHODS The r and omized controlled trial covered 407 children , with a mean age of 8 years . At a school compound three dentists placed sealants in pits and fissures of high caries-risk children . Evaluation by two independent evaluators was conducted after 0.5 , 1 and 2 years . The Kaplan-Meier survival method , ANOVA and t-test were used in analyzing the data . RESULTS 1352 first permanent molars were sealed . 6.6 % of children and 6.8 % of sealants dropped out within 2 years . 27 re-exposed pits and fissures , 20 in occlusal and 7 in smooth surfaces , in 25 children , developed a dentin carious lesion . The cumulative survival of dentin carious lesion-free pits and fissures in the  glass-carbomer sealant group was statistically significantly lower ( 97.4 % ) than those in the high-viscosity glass-ionomer with energy supplied ( 99 % ) and the resin-composite ( 98.9 % ) sealant groups . There was no statistically significant difference in the cumulative survival of dentin carious lesion-free pits and fissures , between the high-viscosity glass-ionomer with ( 99 % ) and without ( 98.3 % ) energy supplied sealant groups , after 2 years . SIGNIFICANCE The survival of dentin carious lesion-free pits and fissures was high in all sealant types . More dentin carious lesions were observed in the glass-carbomer sealant group The present study compares visible-light Delton with Duraphat fluoride varnish for the prevention of occlusal caries in permanent first molars . A clinical trial was carried out in three groups of 6 - 8-yr-old schoolchildren : a sealant group ( 100 children ) , in which Delton light-polymerized fissure sealant was applied to permanent first molars ; a varnish group ( 98 children ) , in which Duraphat was applied to permanent first molars ; and a control group ( 116 children ) .  Replacement ( sealant ) and reapplication ( varnish ) was carried out every 6 months . Percent effectiveness at 24 months ( percentage of saving from caries taking molars as analysis unit ) for those molars initially healthy and with complete occlusal eruption was analyzed . 272 , 252 and 238 molars met the inclusion criteria in the control , varnish and sealant groups , respectively . Of these , 45.2 % , 28.2 % and 10.5 % developed caries after 24 months . The effectiveness was greater in the sealed molars than in the varnished molars ( 62.7 % ) In the GRADE approach , r and omized trials start as high- quality evidence and observational studies as low- quality evidence , but both can be rated down if most of the relevant evidence comes from studies that suffer from a high risk of bias . Well-established limitations of r and omized trials include failure to conceal allocation , failure to blind , loss to follow-up , and failure to appropriately consider the intention-to-treat principle . More recently recognized limitations include stopping early for apparent benefit and selective reporting of outcomes according to the results . Key limitations of observational studies include use of inappropriate controls and failure to adequately adjust for prognostic imbalance . Risk of bias may vary across outcomes ( e.g. , loss to follow-up may be far less for all-cause mortality than for quality of life ) , a consideration that many systematic review s ignore . In deciding whether to rate down for risk of bias -- whether for r and omized trials or observational studies -- authors should not take an approach that averages across studies . Rather , for any individual outcome , when there are some studies with a high risk , and some with a low risk of bias , they should consider including only the studies with a lower risk of bias PURPOSE This study examined the effects of a widely used ( Delton Pit & Fissure Sealant - Light Cure Opaque , DENTSPLY Professional , York , PA ) pit and fissure sealant material on bisphenol A ( BPA ) levels in blood and saliva , among both low and high-dose groups over time . METHODS A convenience sample of 30 adults from the Old Dominion University population were r and omly and evenly divided into 2 independent variable groups : a low-dose group ( 1 occlusal sealant application ) and high-dose group ( 4 occlusal sealant applications ) . A 2 group , time series design was used to examine the presence and concentration of BPA in serum and saliva after sealant placement . Differences comparing low-dose and high-dose groups were examined 1 hour prior ( baseline ) , 1 hour post , 3 hours post and 24 hours after sealant placement , as measured by a direct-competitive BPA Enzyme Linked ImmunoSorbent Assay ( ELISA ) . Hypothesized outcomes were evaluated by applying a parametric , 2 way ANOVA for repeated measures technique to data on the 30 participants ranging in age from 18 to 40 years , and were of mixed gender and ethnicity . RESULTS BPA was detected in the saliva of all participants prior to sealant placement and ranged from 0.07 to 6.00 ng/ml at baseline . Salivary BPA concentration levels peaked over a 3 hour period following sealant placement and returned to baseline levels within 24 hours . BPA was significantly elevated at all post-sealant placement time periods for both the low-dose ( 1 occlusal sealant application ) and high-dose ( 4 occlusal sealant applications ) groups with peak levels of 3.98 ng/ml and 9.08 ng/ml , respectively . The blood serum did not contain BPA at any point in this investigation . CONCLUSIONS Exposure to BPA from sources other than dental resins contributes to salivary baseline concentration levels and indicates environmental exposure and use of products containing BPA . Use of specific molecular formulations of dental sealant material determines the release of BPA , therefore , dental sealant material s should be review ed independently when question ing the release of BPA from dental sealants . In addition , dosage amounts of the dental sealant material used in this study do not influence the serum concentration levels of BPA . Further research is needed to examine the cumulative estrogenic effects of BPA from dental sealants The hypotheses tested were : survival rate of fully and partially retained glass-carbomer sealants is higher than those of high-viscosity glass-ionomer , with and without energy supplied , and that of resin composite ; survival rate of fully and partially retained sealants of high-viscosity glass-ionomer with energy supplied is higher than those without energy supplied . The r and omized clinical trial covered 407 children , with a mean age of 8 years . The evaluation took place after 0.5 , 1 and 2 years . Survival of sealant material in occlusal and in smooth surfaces , using the traditional categorization ( fully and partially retained versus completely lost sealants ) and the modified categorization ( fully and more than 2/3 of the sealant retained versus completely lost sealants ) , were dependent variables . The Kaplan – Meier survival method was used . According to both categorizations of partially retained sealants , the survival of completely and partially retained resin composite sealants  in occlusal and in smooth tooth surfaces was statistically significantly higher , and those of glass-carbomer sealants lower , than those of sealants of the other three groups . There was no statistically significant difference in the survival rates of completely and partially retained high-viscosity glass-ionomer sealants with and without energy supplied in occlusal and in smooth surfaces . After 2 years , glass-carbomer sealant  retention was the poorest , adding energy to high-viscosity glass-ionomer sealant did not increase the retention rate and resin composite sealants were retained the longest . We suggest the use of the modified categorization of partially retained sealants in future studies . It seems not necessary to cure high-viscosity glass-ionomer sealants . The use of glass-carbomer sealants can not be recommended yet 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 ) UNLABELLED The objective of the present study provides further data comparing retention , marginal integrity and caries preventive effects of two fissure sealants ( glass ionomer based ; GC Fuji VII Capsule [ Fuji VII ] and ormocer based ; Admira Seal [ AS ] )  in children . This study was design ed as a r and omized single-blind clinical trial . The permanent first molars ( PFMs ) of 50 children , 7 - 13 years of age ( mean age : 8.9 + /- 1.3 years ) , were sealed with a split-mouth design . Fissure sealants applied to the PFMs according to the manufacturer 's recommendations by one pediatric dentist . Clinical evaluation of the sealants was carried out to record retention , marginal integrity and presence of caries at 6 , 12 , 18 and 24 months after placement by the other pediatric dentist . Kaplan-Meier survival analysis and Cox 's regression models were used to estimate the probability of two sealants success . RESULTS Alpha and Bravo retention rates at the end of follow-up were 13 % and 80 % for Fuji VII and 3 % and 83 % for AS , respectively . For retention and marginal integrity between fissure sealants was found similar survival rates ( p > 0.05 ) . After 24 months , presence of caries was 16 % for Fuji VII and 32 % for AS ( p < 0.05 ) . CONCLUSION Fuji VII and AS exhibited similar retention and marginal integrity during 24 months . However Fuji VII was showed better results than AS for caries preventive effect . Consequently , Fuji VII sealants may be a better choice for preventing occlusal caries PURPOSE The aim of this work is to study and compare the retention rate , caries-preventing and antibacterial effects of resin-modified glass ionomer and flowable composite in comparison to conventional fissure sealant . METHODS Forty-five children aged 7 - 10 years with newly erupted lower first permanent molars were r and omly divided into three equal treatment groups . Group I : sealed by a conventional resin sealant ; Group II : sealed by resin modified glass ionomer ( RMGI ) ; and Group III : sealed by flowable composite .  Retention and caries status of the sealed teeth were recorded after 1 month , 6 months , year and 2 years . In addition , Streptococcus mutans counts were assessed at baseline , 1 day , 1 month , 6 months , 1 year and 2 years after sealant application . Data were analyzed by Fisher exact , chi-square and ANOVA tests . RESULTS Group III and Group I showed significantly higher retention rates than Group II fissure sealant ( p<0.05 ) . There were no differences of the caries-preventive effects between the tested sealant material s throughout the duration of the study . Streptococcus mutans counts were significantly lower in group II compared to group I or group III up to 6 months of the study ( p<0.05 ) . After 1 year of the study the differences of Streptococcus mutans counts were not significant ( p>0.05 ) . CONCLUSION This study indicated a lower retention of RMGI compared to flowable composite and resin sealant without significant difference in caries prevention or long-term bacterial inhibition BACKGROUND The authors conducted a study to survey the perspectives of dentists regarding the 2010 American Dental Association ( ADA ) recommendation to seal non-cavitated carious lesions ( NCCLs ) in children and young adults . METHODS The authors mailed a question naire to a r and omly selected sample of 2,400 general dentists ( GDs ) and pediatric dentists ( PDs ) in the United States . The sample was chosen by the ADA 's Survey Center . The question naire included two photographs of NCCLs ( permanent first molar and premolar ) in a 12-year-old child . Respondents were provided with 
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They also concluded that sealants could minimize the progression of non-cavitated occlusal carious lesions ( also referred to as initial lesions ) that receive a sealant .
Finally , based on the available limited evidence , the panel was unable to provide specific recommendations on the relative merits of 1 type of sealant material over the others .