Pit and fissure sealants for preventing dental decay in permanent teeth.

BACKGROUND: Dental sealants were introduced in the 1960s to help prevent dental caries, mainly in the pits and fissures of occlusal tooth surfaces. Sealants act to prevent bacteria growth that can lead to dental decay. Evidence suggests that fissure sealants are effective in preventing caries in children and adolescents compared to no sealants. Effectiveness may, however, be related to caries incidence level of the population. This is an update of a review published in 2004, 2008 and 2013. OBJECTIVES: To compare the effects of different types of fissure sealants in preventing caries in occlusal surfaces of permanent teeth in children and adolescents. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched: Cochrane Oral Health's Trials Register (to 3 August 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 7), MEDLINE Ovid (1946 to 3 August 2016), and Embase Ovid (1980 to 3 August 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials to 3 August 2016. No restrictions were placed on language or date of publication. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing sealants with no sealant or a different type of sealant material for preventing caries of occlusal surfaces of premolar or molar teeth in children and adolescents aged up to 20 years. Studies required at least 12 months follow-up. We excluded studies that compared compomers to resins/composites. DATA COLLECTION AND ANALYSIS: Two review authors independently screened search results, extracted data and assessed risk of bias of included studies. We presented outcomes for caries or no caries on occlusal surfaces of permanent molar teeth as odds ratio (OR) or risk ratio (RR). We used mean difference (MD) for mean caries increment. All measures were presented with 95% confidence intervals (CI). We conducted meta-analyses using a random-effects model for comparisons where there were more than three trials; otherwise we used the fixed-effect model. We used GRADE methods to assess evidence quality. MAIN RESULTS: We included 38 trials that involved a total of 7924 children; seven trials were new for this update (1693 participants). Fifteen trials evaluated the effects of resin-based sealant versus no sealant (3620 participants in 14 studies plus 575 tooth pairs in one study); three trials with evaluated glass ionomer sealant versus no sealant (905 participants); and 24 trials evaluated one type of sealant versus another (4146 participants). Children were aged from 5 to 16 years. Trials rarely reported background exposure to fluoride of trial participants or baseline caries prevalence. Resin-based sealant versus no sealant: second-, third- and fourth-generation resin-based sealants prevented caries in first permanent molars in children aged 5 to 10 years (at 24 months follow-up: OR 0.12, 95% CI 0.08 to 0.19, 7 trials (5 published in the 1970s; 2 in the 2010s), 1548 children randomised, 1322 children evaluated; moderate-quality evidence). If we were to assume that 16% of the control tooth surfaces were decayed during 24 months of follow-up (160 carious teeth per 1000), then applying a resin-based sealant would reduce the proportion of carious surfaces to 5.2% (95% CI 3.13% to 7.37%). Similarly, assuming that 40% of control tooth surfaces were decayed (400 carious teeth per 1000), then applying a resin-based sealant would reduce the proportion of carious surfaces to 6.25% (95% CI 3.84% to 9.63%). If 70% of control tooth surfaces were decayed, there would be 19% decayed surfaces in the sealant group (95% CI 12.3% to 27.2%). This caries-preventive effect was maintained at longer follow-up but evidence quality and quantity was reduced (e.g. at 48 to 54 months of follow-up: OR 0.21, 95% CI 0.16 to 0.28, 4 trials, 482 children evaluated; RR 0.24, 95% CI 0.12 to 0.45, 203 children evaluated). Although studies were generally well conducted, we assessed blinding of outcome assessment for caries at high risk of bias for all trials (blinding of outcome assessment is not possible in sealant studies because outcome assessors can see and identify sealant). Glass ionomer sealant versus no sealant: was evaluated by three studies. Results at 24 months were inconclusive (very low-quality evidence). One sealant versus another sealant: the relative effectiveness of different types of sealants is unknown (very low-quality evidence). We included 24 trials that directly compared two different sealant materials. Comparisons varied in terms of types of sealant assessed, outcome measures chosen and duration of follow-up. Adverse events: only four trials assessed adverse events. No adverse events were reported. AUTHORS' CONCLUSIONS: Resin-based sealants applied on occlusal surfaces of permanent molars are effective for preventing caries in children and adolescents. Our review found moderate-quality evidence that resin-based sealants reduced caries by between 11% and 51% compared to no sealant, when measured at 24 months. Similar benefit was seen at timepoints up to 48 months; after longer follow-up, the quantity and quality of evidence was reduced. There was insufficient evidence to judge the effectiveness of glass ionomer sealant or the relative effectiveness of different types of sealants. Information on adverse effects was limited but none occurred where this was reported. Further research with long follow-up is needed.

Pit and fissure sealants versus fluoride varnishes for preventing dental decay in the permanent teeth of children and adolescents.

BACKGROUND: Most of the detected increment in dental caries among children and adolescents is confined to occlusal surfaces of posterior permanent molars. Dental sealants and fluoride varnishes are much used preventive options for caries. Although the effectiveness of sealants and fluoride varnishes for controlling caries as compared with no intervention has been demonstrated in clinical trials and summarised in systematic reviews, the relative effectiveness of these two interventions remains unclear. This review is an update of one first published in 2006 and last updated in 2010. OBJECTIVES: Primary objective • To evaluate the relative effectiveness of fissure sealants compared with fluoride varnishes, or fissure sealants together with fluoride varnishes compared with fluoride varnishes alone, for preventing dental caries in the occlusal surfaces of permanent teeth of children and adolescents. Secondary objectives • To evaluate whether effectiveness is influenced by sealant material type and length of follow-up.• To document and report on data concerning adverse events associated with sealants and fluoride varnishes. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 18 December 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 11), MEDLINE via Ovid (1946 to 18 December 2015) and EMBASE via Ovid (1980 to 18 December 2015). We also searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the World Health Organization (WHO) Clinical Trials Registry Platform for ongoing trials. We placed no restrictions on language or date of publication when searching electronic databases. We screened the reference lists of identified trials and review articles for additional relevant studies. SELECTION CRITERIA: We included randomised controlled trials with at least 12 months of follow-up comparing fissure sealants, or fissure sealants together with fluoride varnishes, versus fluoride varnishes for preventing caries in the occlusal surfaces of permanent premolar or molar teeth, in participants younger than 20 years of age at the start of the study. DATA COLLECTION AND ANALYSIS: Two review authors independently screened search results, extracted data and assessed risk of bias of included studies. We attempted to contact study authors to obtain missing or unclear information.We grouped and analysed studies on the basis of sealant material type (resin-based sealant and glass ionomer-based sealant: glass ionomer and resin-modified glass ionomer) and different follow-up periods. We calculated the odds ratio (OR) for caries or no caries on occlusal surfaces of permanent molar teeth. For trials with a split-mouth design, we used the Becker-Balagtas odds ratio. For continuous outcomes and data, we used means and standard deviations to obtain mean differences. We presented all measures with 95% confidence intervals (CIs).We assessed the quality of the evidence using GRADE (Grades of Recommendation, Assessment, Development and Evaluation) methods.We conducted meta-analysis using the fixed-effect model, as data from only two studies were combined. We had planned to conduct meta-analyses using a random-effects model when more than three trials were included in the meta-analysis. MAIN RESULTS: In this review, we included eight trials with 1746 participants (four of the trials were new since the 2010 update). Seven trials (1127 participants) contributed to the analyses, and children involved were five to 10 years of age at the start of the trial. Sealant versus fluoride varnish Resin-based fissure sealants compared with fluoride varnishes Four trials evaluated this comparison (three of them contributing to the analyses). Compared with fluoride varnish, resin-based sealants prevented more caries in first permanent molars at two-year follow-up (two studies in the meta-analysis with pooled odds ratio (OR) 0.69, 95% confidence interval (CI) 0.50 to 0.94; P value = 0.02; I(2) = 0%; 358 children evaluated). We assessed the body of evidence as low quality. The caries-preventive benefit for sealants was maintained at longer follow-up in one trial at high risk of bias: 26.6% of sealant teeth and 55.8% of fluoride-varnished teeth had developed caries when 75 children were evaluated at nine years of follow-up. Glass ionomer-based sealants compared with fluoride varnishes Three trials evaluated this comparison: one trial with chemically cured glass ionomer and two with resin-modified glass ionomer. Researchers reported similar caries increment between study groups regardless of which glass ionomer material was used in a trial. Study designs were clinically diverse, and meta-analysis could not be conducted. The body of evidence was assessed as of very low quality. Sealant together with fluoride varnish versus fluoride varnish alone One split-mouth trial analysing 92 children at two-year follow-up found a significant difference in favour of resin-based fissure sealant together with fluoride varnish compared with fluoride varnish only (OR 0.30, 95% CI 0.17 to 0.55). The body of evidence was assessed as low quality. Adverse events Three trials (two with resin-based sealant material and one with resin-modified glass ionomer) reported that no adverse events resulted from use of sealants or fluoride varnishes. The other five studies did not mention adverse events. AUTHORS' CONCLUSIONS: Currently, scarce and clinically diverse data are available on the comparison of sealants and fluoride varnish applications; therefore it is not possible to draw clear conclusions about possible differences in effectiveness for preventing or controlling dental caries on occlusal surfaces of permanent molars. The conclusions of this updated review remain the same as those of the last update (in 2010). We found some low-quality evidence suggesting the superiority of resin-based fissure sealants over fluoride varnish applications for preventing occlusal caries in permanent molars, and other low-quality evidence for benefits of resin-based sealant and fluoride varnish over fluoride varnish alone. Regarding glass ionomer sealant versus fluoride varnish comparisons, we assessed the quality of the evidence as very low and could draw no conclusions.

Assessment of removed dental implants in Finland from 1994 to 2012.

PURPOSE: The National Institute for Health and Welfare in Finland (THL) has maintained the Finnish Dental Implant Register since April 1994. The aim of this study was to use the Dental Implant Register to assess the influence of patient characteristics and background factors on dental implant removals in Finland from 1994 to 2012. MATERIALS AND METHODS: THL granted permission to access the Finnish Dental lmplant Register (1994 to 2012) and assess the following factors: total implant placements, total implant removals, time from implant placement to removal, implant types, implant lengths, placed and failed implants by jaw and tooth type, and patient sex and age. RESULTS: A total of 198,538 dental implants (51 different types) were placed between 1994 and 2012. A total of 3,318 (1.7%) of the placed implants were removed during the observation period. A total of 1,856 (1.8%) of the placed implants were removed from the maxilla and 1,462 (1.5%) from the mandible (P < .001). A slight difference in the sex distribution concerning implant failures (3.1% in men vs 2.3% in women) was observed. The median removal time was 247 days postoperatively (range 0 to 11,383 days), and one-third of the implants were removed within the first 142 days. Most of the placed implants were 10 mm or longer (93.3%) with 12 mm being the most commonly used length (23.9%). Shorter implants (8 mm or less) were removed more often (2.5% removal rate) than 9 mm or longer implants (1.5% removal rate). The IMZ Implant system demonstrated the highest overall removal rates (8.5%), while Brånemark Nobel Direct (0.6%) demonstrated the lowest removal rates. Of the most commonly placed implant types (together comprising 60.9% of all implants placed), the Straumann (1.2%) and the Astra Implant (1.2%) systems demonstrated equally low removal rates. CONCLUSIONS: The overall dental implant removal rates in Finland are low. Only slight differences in gender and implant position were observed.

Sealants for preventing dental decay in the permanent teeth.

BACKGROUND: Dental sealants were introduced in the 1960s to help prevent dental caries in the pits and fissures of mainly the occlusal tooth surfaces. Sealants act to prevent the growth of bacteria that can lead to dental decay. There is evidence to suggest that fissure sealants are effective in preventing caries in children and adolescents when compared to no sealants. Their effectiveness may be related to the caries prevalence in the population. OBJECTIVES: To compare the effects of different types of fissure sealants in preventing caries in permanent teeth in children and adolescents. SEARCH METHODS: We searched the Cochrane Oral Health Group's Trials Register (to 1 November 2012); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 7); MEDLINE via OVID (1946 to 1 November 2012); EMBASE via OVID (1980 to 1 November 2012); SCISEARCH, CAplus, INSPEC, NTIS and PASCAL via STN Easy (to 1 September 2012); and DARE, NHS EED and HTA (via the CAIRS web interface to 29 March 2012 and thereafter via Metaxis interface to September 2012). There were no language or publication restrictions. We also searched for ongoing trials via ClinicalTrials.gov (to 23 July 2012). SELECTION CRITERIA: Randomised or quasi-randomised controlled trials of at least 12 months duration comparing sealants for preventing caries of occlusal or approximal surfaces of premolar or molar teeth with no sealant or different type of sealant in children and adolescents under 20 years of age. DATA COLLECTION AND ANALYSIS: Two review authors independently screened search results, extracted data and assessed trial quality. We calculated the odds ratio (OR) for caries or no caries on occlusal surfaces of permanent molar teeth. For trials with a split-mouth design, the Becker-Balagtas odds ratio was used. For mean caries increment we used the mean difference. All measures are presented with 95% confidence intervals (CI). The quality of the evidence was assessed using GRADE methods. We conducted the meta-analyses using a random-effects model for those comparisons where there were more than three trials in the same comparison, otherwise the fixed-effect model was used. MAIN RESULTS: Thirty-four trials are included in the review. Twelve trials evaluated the effects of sealant compared with no sealant (2575 participants) (one of those 12 trials stated only number of tooth pairs); 21 trials evaluated one type of sealant compared with another (3202 participants); and one trial evaluated two different types of sealant and no sealant (752 participants). Children were aged from 5 to 16 years. Trials rarely reported the background exposure to fluoride of the trial participants or the baseline caries prevalence.- Resin-based sealant compared with no sealant: Compared to control without sealant, second or third or fourth generation resin-based sealants prevented caries in first permanent molars in children aged 5 to 10 years (at 2 years of follow-up odds ratio (OR) 0.12, 95% confidence interval (CI) 0.07 to 0.19, six trials (five published in the 1970s and one in 2012), at low risk of bias, 1259 children randomised, 1066 children evaluated, moderate quality evidence). If we were to assume that 40% of the control tooth surfaces were decayed during 2 years of follow-up (400 carious teeth per 1000), then applying a resin-based sealant will reduce the proportion of the carious surfaces to 6.25% (95% CI 3.84% to 9.63%); similarly if we were to assume that 70% of the control tooth surfaces were decayed  (700 carious teeth per 1000), then applying a resin-based sealant will reduce the proportion of the carious surfaces to 18.92% (95% CI 12.28% to 27.18%). This caries preventive effect was maintained at longer follow-up but both the quality and quantity of the evidence was reduced (e.g. at 48 to 54 months of follow-up OR 0.21, 95% CI 0.16 to 0.28, four trials (two studies at low risk of bias and two studies at high risk of bias), 482 children evaluated; risk ratio (RR) 0.24, 95% CI 0.12 to 0.45, one study at unclear risk of bias, 203 children evaluated).- Glass ionomer sealant compared with no sealant: There is insufficient evidence to make any conclusions about whether glass ionomer sealants, prevent caries compared to no sealant at 24-month follow-up (mean difference in DFS -0.18, 95% CI -0.39 to 0.03, one trial at unclear risk of bias, 452 children randomised, 404 children evaluated, very low quality evidence).- Sealant compared with another sealant: The relative effectiveness of different types of sealants remained inconclusive in this review. Twenty-one trials directly compared two different sealant materials. Several different comparisons were made according to type of sealant, outcome measure and duration of follow-up. There was great variation with regard to comparisons, outcomes, time of outcomes reported and background fluoride exposure if this was reported.Fifteen trials compared glass ionomer with resin sealants and there is insufficient evidence to make any conclusions about the superiority of either of the two materials. Although there were 15 trials the event rate was very low in many of these which restricted their contribution to the results.Three trials compared resin-modified glass ionomer with resin sealant and reported inconsistent results.Two small low quality trials compared polyacid-modified resin sealants with resin sealants and found no difference in caries after 2 years.- Adverse effects: Only two trials mentioned adverse effects and stated that no adverse effects were reported by participants. AUTHORS' CONCLUSIONS: The application of sealants is a recommended procedure to prevent or control caries. Sealing the occlusal surfaces of permanent molars in children and adolescents reduces caries up to 48 months when compared to no sealant, after longer follow-up the quantity and quality of the evidence is reduced. The review revealed that sealants are effective in high risk children but information on the magnitude of the benefit of sealing in other conditions is scarce. The relative effectiveness of different types of sealants has yet to be established.

Occupational exposure in dentistry and miscarriage.

BACKGROUND: Information on the reproductive effects of chemical exposures in dental work is sparse or inconsistent. AIM: To investigate whether dental workers exposed to acrylate compounds, mercury amalgam, solvents or disinfectants are at an increased risk of miscarriage. METHODS: The study was conducted among women dental workers and a comparison group of workers occupationally unexposed to dental restorative materials. Information on pregnancies was obtained from national registers and outpatient units of hospitals. Data on occupational exposure were obtained using postal questionnaires. The final study population included 222 cases of miscarriage and 498 controls (births). An occupational hygienist assessed exposure to acrylate compounds, disinfectants and solvents. Exposure to other agents was assessed on the basis of the questionnaire data. Odds ratios (ORs) and confidence intervals (CIs) were estimated using conditional logistic regression. RESULTS: The ORs adjusted for confounding factors were increased for moderate-exposure and high-exposure categories of mercury amalgam (OR 2.0, 95% CI 1.0 to 4.1 and OR 1.3, 95% CI 0.6 to 2.5, respectively). The risk was slightly increased for the highest-exposure category of 2-hydroxyethylmethacrylate (OR 1.4, 95% CI 0.7 to 2.6) and polymethylmethacrylate dust (OR 1.4, 95% CI 0.8 to 2.4). A slightly increased risk was also detected for likely exposure to organic solvents (OR 1.4, 95% CI 0.8 to 2.3) and disinfectants (OR 1.5, 95% CI 0.9 to 2.7). CONCLUSIONS: No strong association or consistent dose-response relationship was observed between exposure to chemical agents in dental work and the risk of miscarriage. A slightly increased risk was found for exposure to mercury amalgam, some acrylate compounds, solvents and disinfectants. These findings indicate that the possibility of a weak association between exposure to these agents and an increased risk of miscarriage cannot be excluded.

Reasons for restorative therapy and the longevity of restorations in adults.

The aim of this study was to obtain information on the restorative dental care of adults in Finland. A random sample of private dentists was drawn from the register, and in spring 2000 they were sent a questionnaire requesting them to record information for each restoration placed during one ordinary working day. A total of 800 dentists were contacted and 548 responded. The dentists reported placement of 3,455 restorations. Of these, 5% were Class I, 36% were Class II, 13% were Class III, 9% were Class IV, 21% were Class V, and 16% were extensive restorations including 4 or more surfaces. Overall, composite resin was the most common restorative material, and it was used in 79% of the restorations, whereas amalgam was used in 50%, compomers in 4%, and glass ionomers (either conventional or resin-modified) in 7% of cases. In 5%, of the cases, the tooth was restored with indirect restorative methods, using either gold or ceramic materials. Of the treatments, 65% were replacements of previous restorations. Secondary caries was the most common reason for replacement (36%, 52%, and 41% for composite, glass ionomer, and amalgam, respectively). Other common reasons were fractures of the tooth or restoration (23%, 11%, and 22% for composite, glass ionomer, and amalgam, respectively) and lost composite restorations (16%). The median age of failed restorations was 15 years for amalgam, 6 years for composite, and 7 years for conventional glass ionomer. Although the longevity of tooth coloured restorations was shorter than that of amalgam, comparisons with our previous studies indicate improved survival periods for tooth coloured materials.