Abstract A multicenter, randomized controlled clinical trial evaluated the effectiveness of two treatments for deep caries lesions in permanent molars - selective caries removal (SCR) to soft dentin with restoration in a single visit, and stepwise excavation (SW) - regarding pulp vitality for a 5-year follow-up period. The present study aimed to determine the cost-effectiveness of these treatments. Treatments were conducted in two Brazilian cities (Brasília and Porto Alegre). At baseline, 299 permanent molars (233 patients) were treated and 229 teeth (174 patients) were evaluated after 5 years. The discounted cash flow method was adopted. The total cost of each treatment was calculated, and the failure cost (endodontic treatment + restoration) was added to the final cost, according to the 5-year failure rates of each therapy (20% for SCR and 44% for SW). A public health service unit composed of three dentists in 4-hour work shifts was used to calculate the monetary value of the treatments, assuming a total of 528 treatments/month. Considering the 229 teeth evaluated after 5 years (115 SCR and 114 SW), SCR provided savings of 43% (amalgam) and 41% (resin composite) per treatment, compared to SW. The SCR technique provides benefits for public finances (direct economy) and for public health services (increase in the number of treatments performed). Considering that maximizing profit and reducing costs are powerful motivating factors for adopting a certain treatment, this study provides data to better support the decision-making process, regarding the management of deep caries lesions in permanent molars.

Abstract This cohort study assessed the association between toothbrushing frequency and the increment of dental caries and tooth loss in a population-based sample of southern Brazilian adolescents, to investigate whether there is any additional benefit in performing a third daily brushing. At baseline, 1,528 12-year-old schoolchildren attending 42 schools were examined for gingivitis and dental caries, and answered a questionnaire. After a mean period of 2.5 years, 801 schoolchildren were re-examined. Dental caries and tooth loss increment were outcomes of the study. The main predictor variable was toothbrushing frequency (≥3 times/day vs. twice/day or ≤1 time/day). Poisson regression models were used to estimate the risk for caries and tooth loss increment. Incidence risk ratios (IRR) and 95% confidence intervals (CI) were estimated. The final model adjusted for sociodemographic, behavioral, and clinical variables showed that brushing twice/day afforded 40% greater risk (IRR = 1.40; 95%CI: 1.02–1.92) for caries increment than ≥3 times/day. Regarding the tooth loss increment, adolescents who brushed their teeth twice/day had a fourfold greater risk (IRR = 3.92; 95%CI: 1.23–12.49) than those who brushed ≥ 3 times/day. Sex, school type, and gingivitis were found to act as effect modifiers, inasmuch as a third daily brushing presented advantages against tooth loss only for girls, public school attendees, and those with ≥ 50% of bleeding sites. This study suggests that adolescents benefit from a third daily toothbrushing. Increasing brushing frequency to 3 times/day may be a suitable strategy to control dental caries and tooth loss among high-risk adolescents.

Abstract Objective This study aimed to analyze the functional profile of supragingival biofilm from sound (CAs), active (CAa), and inactive (CAi) enamel caries lesions from caries-active individuals to provide insights into the diversity of biological processes regarding biofilm dysbiosis. Methodology A metatranscriptome analysis was performed in biofilm samples collected from five caries-active individuals. Total RNA was extracted, and the microbial cDNAs were obtained and sequenced (Illumina HiSeq3000). Trimmed data were submitted to the SqueezeMeta pipeline in the co-assembly mode for functional analysis and further differential gene expression analysis (DESeq2). Results Bioinformatics analysis of mRNAs revealed a similar functional profile related to all analyzed conditions (CAa, CAi, and CAs). However, active and inactive surfaces share up-regulated genes (gtsA; qrtT; tqsA; pimB; EPHX1) related to virulence traits that were not overrepresented in sound surfaces. From a functional perspective, what matters most is the individual carious status rather than the surface condition. Therefore, pooling samples from various sites can be carried out using naturally developed oral biofilms but should preferably include carious surfaces. Conclusion Metatranscriptome data from subjects with caries activity have shown that biofilms from sound, arrested, and active lesions are similar in composition and function.

Abstract: This longitudinal study aimed to assess the association between the use of fixed orthodontic appliances and the incidence/increment of active caries lesions in adolescents and young adults over a one-year period. A total of 135 10-30-year-old individuals were divided into two groups: Group G0 was composed of individuals who required orthodontic treatment, but who did not undergo fixed orthodontic therapy over the study period (n=70); Group G1 was composed of individuals who used a fixed orthodontic appliance for 1 year (n=65). Data collection included a questionnaire and clinical oral examinations (plaque index, gingival index, and dental caries index), performed at baseline and after 1 year. Caries examination was performed by a single calibrated examiner, after tooth cleaning and drying, and included the recording of non-cavitated and cavitated, inactive and active lesions of all tooth surfaces. Poisson regression models were used to assess the association between the group and the following study outcomes: incidence (binary variable) and increment (counting variable). The incidence of active caries lesions was 4.8% in G0 and 39.6% in G1. The mean increment of active caries lesions was 0.14 in G0 and 0.61 in G1. G1 showed a greater risk of developing active caries lesions than G0 (incidence analysis, adjusted IRR=9.48, 95%CI=2.62-34.30; increment analysis, adjusted IRR=4.13; 95%CI=1.94-8.79). In conclusion, this study showed that individuals undergoing fixed orthodontic therapy for 1 year had a significantly higher incidence and increment of active caries lesions than those without a fixed appliance.

Abstract This study aimed to assess the prevalence, extent, and associated factors of underlying dentin shadows (UDS) in the occlusal surfaces of permanent posterior teeth among 12-year-old schoolchildren from southern Brazil. A population-based cross-sectional study that included a representative sample of 1,528 schoolchildren was conducted in Porto Alegre, southern Brazil (participation rate: 83.2%). A questionnaire on sociodemographic characteristics, behavioral habits, and access to dental services was sent to parents/legal guardians of each student selected. Caries examination included the recording of non-cavitated and cavitated lesions, including the presence of UDS, as defined by the ICDAS Group (i.e., a shadow of discolored dentin visible through an apparently intact enamel surface that may or may not show signs of localized breakdown – ICDAS Code 4). The association between predictor variables and UDS prevalence was assessed using survey Poisson regression models. The prevalence of UDS was 6.3% (95%CI = 1.2 –11.3). The mean number of affected teeth among the schoolchildren presenting UDS was 1.51 (95%CI = 1.40 –1.61), ranging from 1 to 6. Type of school (public, PR = 2.23, 95%CI = 1.22 –4.07) and caries experience (DMFT 1-2, PR = 2.41, 95%CI = 1.15 –5.04; DMFT ≥ 3, PR = 3.09, 95%CI = 1.52 –6.27) were significantly associated with UDS prevalence. In conclusion, this population-based cross-sectional study found a low prevalence of UDS in the occlusal surfaces of the permanent posterior teeth of 12-year-old southern Brazilian schoolchildren. Overall caries experience and type of school were associated with UDS in this population.

RESUMO Objetivo O objetivo deste estudo foi avaliar a disponibilidade e a estabilidade da fração solúvel de flúor nos dentifrícios fluoretados comercialmente disponíveis no Uruguai. Métodos Quatorze dentifrícios fluoretados de quatro diferentes fabricantes foram analisados. Análises randomizadas e cegas foram realizadas em duplicata para cada dentifrício no momento da aquisição (amostras frescas) e depois de 12 meses de armazenamento em temperatura ambiente (amostras envelhecidas). As concentrações de flúor total e flúor solúvel total foram determinadas usando um eletrodo específico para flúor. Resultados As concentrações de flúor total de todos os produtos testados foram menores do que os níveis de flúor especificados pelos fabricantes. Os valores das frações de flúor solúvel total foram menores do que as concentrações de flúor total nas amostras frescas de cinco dentifrícios e nas amostras envelhecidas de 10 dentifrícios (p < 0.05). Três dentifrícios apresentaram as frações de flúor solúvel total insuficientes e instáveis (< 60%) e cinco dentifrícios tiveram apenas frações instáveis de flúor solúvel total (<1000 ppm) após 12 meses. Conclusão Baseado nosresultados deste estudo pode-se concluir que dos quatorze dentifrícios fluoretados comercialmente disponíveis no Uruguai analisados neste estudo, três produtos apresentaram insuficientes e instáveis frações quimicamente ativas de flúor e cinco outros dentifrícios tiveram falta de estabilidade o que pode comprometer suas eficácias. É necessário revisar as orientações sobre dentifrícios fluoretados no Uruguai a fim de garantir um benefício ótimo para a população.

ABSTRACT Objective The aim of this study was to evaluate the availability and stability of soluble fluoride fraction in commercial fluoride toothpastes available in Uruguay. Methods Fourteen fluoride toothpastes from four different manufacturers were analyzed. Randomized and blinded analyses were performed in duplicate for each dentifrice at the time of purchase (fresh samples) and after 12 months of storage at room temperature (aged samples). Total fluoride and total soluble fluoride concentrations were measured using a fluoride specific electrode. Results Total fluoride concentrations in all of the products were lower than the F levels specified by the manufacturers. Total soluble fluoride fractions were lower than the total fluoride concentrations in fresh samples of five toothpastes and in aged samples of ten toothpastes (p < 0.05). Three toothpastes had insufficient and unstable total soluble fluoride fractions (< 60%) and five toothpastes had only unstable total soluble fluoride fractions (<1000 ppm) after 12 months. Conclusion Based on theresults of this study, it can be concluded that from fourteen Uruguayan commercial fluoride toothpastes analyzed in this study, three toothpastes have insufficient and unstable chemically active F fractions and five other toothpastes have the lack of stability which may compromise their efficacies. Review the guidelines on fluoride dentifrices in Uruguay is necessary, in order to ensure optimum benefit for population.

Abstract Objective This study sought to analyze the gene expression of Candida albicans in sound root surface and root caries lesions, exploring its role in root caries pathogenesis. Methodology The differential gene expression of C. albicans and the specific genes related to cariogenic traits were studied in association with samples of biofilm collected from exposed sound root surface (SRS, n=10) and from biofilm and carious dentin of active root carious lesions (RC, n=9). The total microbial RNA was extracted, and the cDNA libraries were prepared and sequenced on the Illumina Hi-Seq2500. Unique reads were mapped to 163 oral microbial reference genomes including two chromosomes of C. albicans SC5314 (14,217 genes). The putative presence of C. albicans was estimated (sum of reads/total number of genes≥1) in each sample. Count data were normalized (using the DESeq method package) to analyze differential gene expression (using the DESeq2R package) applying the Benjamini-Hochberg correction (FDR<0.05). Results Two genes (CaO19.610, FDR=0.009; CaO19.2506, FDR=0.018) were up-regulated on SRS, and their functions are related to biofilm formation. Seven genes ( UTP20 , FDR=0.018; ITR1 , FDR=0.036; DHN6 , FDR=0.046; CaO19.7197 , FDR=0.046; CaO19.7838 , FDR=0.046; STT4 , FDR=0.046; GUT1 , FDR=0.046) were up-regulated on RC and their functions are related to metabolic activity, sugar transport, stress tolerance, invasion and pH regulation. The use of alternative carbon sources, including lactate, and the ability to form hypha may be a unique trait of C. albicans influencing biofilm virulence. Conclusions C. albicans is metabolically active in SRS and RC biofilm, with different roles in health and disease.

Abstract The aim of this study was to assess the association between weight status and ΔDMFS among 12-year-old schoolchildren from South Brazil. A total of 801 12-year-old schoolchildren were followed-up for 2.5 ± 0.3 years. Data collection included questionnaire, recording of anthropometric measures (height and weight), and caries examination. The outcome was the difference between DMFS (number of decayed, missing or filled surfaces) at follow-up and baseline (ΔDMFS). Weight status, based on body mass index-for-age Z-scores, was considered the main predictor variable. Negative binomial regression models were used to model the association, and rate ratios and their 95% confidence intervals were estimated. A multivariable fractional polynomial model was used to further explore the relationship between obesity and dental caries. DMFS increased by 0.86 (95%CI = 0.65–1.07), 0.91 (95%CI = 0.59–1.23), and 0.42 (95%CI = 0.03–0.80) for normal weight, overweight, and obese schoolchildren, respectively. Obese adolescents had significantly lower ΔDMFS than normal weight ones (p < 0.05). No significant association between categories of weight status and ΔDMFS was found (overweight, IRR=0.92, 95%CI = 0.69–1.21, p = 0.54; obese IRR = 0.75, 95%CI = 0.51–1.12, p = 0.16). However, the multivariable fractional polynomial model showed an inverted U shaped relationship with a decreasing ΔDMFS with increasing BMI (p < 0.05). This population-based longitudinal study showed an inverse association between obesity and ΔDMFS over a 2.5-year period among South Brazilian adolescents.

Abstract: The aim of this study was to determine the occurrence of gingivitis and calculus and their predictors in a population of adults in Brazil. A representative sample of 758 adults from 35 to 59 years of age from Porto Alegre city was examined. A structured questionnaire was applied. The Gingival Bleeding Index and the presence of calculus were measured at 4 sites/tooth. Multivariable logistic models were fitted to determine the predictors for gingival bleeding at >20% of sites. Overall, 96.5% (95% confidence interval [CI]=95.1-98.0) of individuals had ≥ 1 bleeding site. The mean percentages of sites with gingivitis and calculus were 26.1% and 44.6%, respectively. The odds of gingivitis decreased by ∼45% for individuals ≥40 years old compared to younger adults. Individuals that never performed interproximal cleaning and non-whites had an approximately two times higher chance of gingivitis. Smokers had lower chances of gingivitis than never-smokers (odds ratio=0.40; 95% CI=0.24-0.68). Higher numbers of missing teeth were associated with higher chances of gingivitis. The percentage of calculus was significantly associated with skin color, education, proximal cleaning, smoking exposure, dental visits, and tooth loss. It can be concluded that the occurrence of gingivitis and calculus was high in this Brazilian population, and it was associated with age, skin color, education, self-reported proximal cleaning, smoking, dental care, and tooth loss.

Resumo O objetivo deste ensaio clínico randomizado foi comparar os microrganismos remanescentes após tratamentos baseados em remoção total de tecido cariado e selamento e a remoção seletiva de tecido cariado e selamento. Pacientes com lesões de cárie ativas em molares permanentes foram divididos aleatoriamente em dois grupos: grupo teste (remoção seletiva de tecido cariado-SCR; n=18), e grupo de controle (remoção total de tecido cariado-CCR; n=18). Amostras de dentina foram obtidas após a remoção da tecido cariado e após 3 meses de selamento das cavidades. Streptococcus spp., Streptococcus mutans, Lactobacillus spp. e microrganismos viáveis totais foram cultivados para contagem de células e frequência de isolamento de espécies. CCR resultou em menores contagens totais de microorganismos viáveis (p≤0,001), Streptococcus spp. (p≤0,001) e Lactobacillus spp. (p≤0,001) inicialmente. Entretanto, após o selamento, uma redução significativa nas contagens totais de microrganismos viáveis, Streptococcus spp. e Lactobacillus spp. resultou em nenhuma diferença entre os grupos após 3 meses. Conclui-se que a remoção seletiva de cárie é tão seletiva quanto a remoção completa de cárie na redução da infecção dentinária após três meses com selamento da lesão.

Abstract The aim of this randomized clinical trial was to compare the remaining microbial load after treatments based on complete and selective caries removal and sealing. Patients with active carious lesions in a permanent molar were randomly allocated into 2 groups: a test group (selective caries removal-SCR; n=18) and a control group (complete caries removal - CCR; n=18). Dentin samples were collected following the excavation and three months after sealing. Streptococcus species, Streptococcus mutans, Lactobacillus species, and total viable microorganisms were cultured to count the viable cells and frequency of species isolation. CCR resulted in significant lower total viable microorganisms counts (p≤0.001), Streptococcus species (p≤0.001) and Lactobacillus species (p≤0.001) initially. However, after sealing, a decrease in total viable microorganisms, Streptococcus species, and Lactobacillus species in the SCR resulted in no difference between the groups after 3 months. In conclusion, selective caries removal is as effective as complete caries removal in reducing dentin bacterial load 3 months after sealing.

Abstract This randomized clinical trial aimed to assess the efficacy of sealing occlusal carious lesions in permanent teeth. The sample consisted of 54 occlusal carious lesions in permanent molars and premolars of 49 patients aged 8–43 years (median: 19 years). The inclusion criteria comprised the presence of a cavity with no access allowing biofilm control. The maximum depth of the lesion was the middle third of the dentin thickness, as assessed by bitewing radiography. The teeth were randomly assigned to sealant treatment (n = 28) or restorative treatment (n = 26). Clinical and radiographic examinations were performed after 1 year and after 3–4 years. The outcomes depended on the clinical performance of the sealant/restoration and the control of caries progression observed radiographically. Survival analysis was performed to assess success rates. Over the 3-4 years of monitoring, 2 sealants were totally lost, 1 needed repair, and 1 showed caries progression, totaling 4 failures in the sealant group. In the restoration group, 1 failure was observed (in need of repair). The success rates were 76% and 94% in the sealant and the restoration groups, respectively (p > 0.05). The sealing of occlusal carious lesions in permanent teeth succeeded in controlling caries over a 3–4-year period. However, sealed carious lesions require patient compliance in attending regular follow-ups to control the occurrence of clinical failures of the sealants.

This single-blind, randomized, crossover study aimed at assessing the long-term fluoride concentrations in saliva and in dental biofilm after different home-use fluoride treatments. The study volunteers (n = 38) were residents of an area with fluoridated drinking water. They were administered four treatments, each of which lasted for one week: twice-daily placebo dentifrice, twice-daily fluoride dentifrice, twice-daily fluoride dentifrice and once-daily fluoride mouthrinse, and thrice-daily fluoride dentifrice. At the end of each treatment period, samples of unstimulated saliva and dental biofilm were collected 8 h after the last oral hygiene procedure. Fluoride concentrations in saliva and dental biofilm were analyzed using a specific electrode. The fluoride concentrations in saliva and dental biofilm 8 h after the last use of fluoride products did not differ among treatments. The results of this study suggest that treatments with home-use fluoride products have no long-term effect on fluoride concentrations in saliva and in dental biofilm of residents of an area with a fluoridated water supply.

The aim of this study was to evaluate the effect of a commercial lactose-containing stevioside sweetener on biofilm acidogenicity in vivo. Nine volunteers refrained from brushing their teeth for 3 days in five phases. On the 4th day of each phase, the pH of the biofilm was measured by the “Strip method”. Interproximal plaque pH was measured before and up to 60 minutes after a 10 mL mouthrinse for 1 minute with the test solutions: I - sweetener with 93% lactose and 7% stevioside; II - sweetener with 6.8% saccharin, 13.6% cyclamate, and 0.82% stevioside; III - 18% sucrose solution (positive control); IV - mineral water (negative control); and V- 93% lactose solution. The results revealed that the most pronounced pH fall was found with sucrose (positive control), followed by the 93% lactose solution, the sweetener with lactose + stevioside, the sweetener with saccharin + cyclamate + stevioside, and finally water (negative control). According to the area under the curve, the two sweeteners containing stevioside were significantly different, and the sweetener with lactose + stevioside was significantly different from water but not from sucrose. The critical pH for dentin demineralization (pH ≤ 6.5) was reached by all volunteers after rinsing with sucrose solution, lactose solution, and the stevioside + lactose sweetener. Analysis of the data suggests that lactose-containing stevioside sweeteners may be cariogenic, especially to dentin.

OBJETIVO: Este estudo avaliou o efeito de diferentes posologias do verniz de clorexidina a 1% (V-CHX1%) na composição bioquímica do biofilme dental. METODOLOGIA: Voluntários com níveis de Streptococcus mutans > 10(5) UFC/mL saliva, foram divididos em 4 grupos: A - uma única aplicação do V-CHX1%; B - aplicações de 1x/dia do V-CHX1% durante 3 dias consecutivos; C - 3 aplicações de 1x/dia do V-CHX1% com intervalos de 4 dias entre elas; D - aplicações de 1x/dia do verniz placebo durante 3 dias consecutivos. Amostras de biofilme dental foram coletadas, no início e após 1, 4 e 8 semanas das aplicações dos vernizes, e analisadas quanto às concentrações de fosfato inorgânico (Pi) e polissacarídeos insolúveis (PI). RESULTADOS: Não foram observadas diferenças, em relação à composição bioquímica, entre os grupos durante os diferentes períodos experimentais. Foi observado, após 1 semana, um aumento significativo nas concentrações de Pi, retornando aos valores iniciais após 4 semanas. Todos os grupos apresentaram uma redução significativa na concentração de PI por mais de 8 semanas após os tratamentos. CONCLUSÃO: A aplicação do verniz resultou em uma modificação do biofilme dentário tornando-o menos cariogênico.

PURPOSE: This investigation evaluated in a randomized controlled study the effect of different 1% chlorhexidine varnish (1%CHX-V) regimens on biochemical composition of the dental biofilm. METHODS: Subjects with mutans streptococci > 10(5) CFU/mL saliva, were allocated into 4 groups: A - single 1% CHX-V application; B - 1% CHX-V was applied once daily on 3 consecutive days; C - 1% CHX-V was applied 3 times with an interval of 4 days between each application; and D - placebo varnish was applied once daily on 3 consecutive days. Dental biofilm samples were collected at baseline and 1, 4, and 8 weeks after the final varnish application and evaluated for inorganic phosphate and insoluble polysaccharide concentrations. RESULTS: No difference was observed between all groups during the different experimental periods in relation to biochemical composition. After 1 week, a significant increase was observed in inorganic phosphate concentration, returning to baseline values after 4 weeks. All groups showed a significant decrease in insoluble polysaccharide concentration for more than 8 weeks after treatment. CONCLUSION: Varnish application resulted in modification of the dental biofilm toward a less cariogenic one.

The effect of a combination of topical fluoridation methods for inhibition of enamel demineralization in the face of a cariogenic challenge has not been clearly established. This in situ crossover study aimed to assess whether the addition of daily use of fluoride mouthrinse (FR) to that of fluoride dentifrice (FD) is equivalent to increasing the frequency of FD application in terms of the effect on enamel demineralization and fluoride content. Over 3 phases of 14 days each, 12 volunteers wore appliances containing enamel blocks exposed to a 20 % sucrose solution 8 times/day. During each phase the blocks underwent one of the following treatments: 2x/day FD, 2x/day FD + 1x/day FR, and 3x/day FD. The blocks were assessed for hardness and fluoride content. Three x/day FD did not differ from 2x/day + 1x/day FR, however it enhanced demineralization protection when compared to 2x/day FD. All treatments produced an increase in enamel fluoride content compared to no treatment (sound blocks) (p < 0.05), but the differences between them were not significant. The results of this study suggest that the daily use of fluoride mouthrinse combined with that of fluoride dentifrice has similar effects on enamel demineralization and fluoride content when compared to increasing the frequency of fluoride dentifrice use.