Oral conditions of children with microcephaly associated with congenital Zika syndrome: a cross-sectional study

The aim of the present study was to compare the oral conditions of children with congenital Zika syndrome (CZS)-associated microcephaly, non-CZS-associated microcephaly, and normotypical children, as well as to characterize their sociodemographic aspects and medical history. A paired cross-sectional study was carried out on 14 children with CZS-associated microcephaly and 24 age-matched controls, in Belo Horizonte, in southeastern Brazil. Children's oral conditions were assessed: dental caries experience (dmft/DMFT indices); developmental defects of enamel (DDE) index; dental anomalies; mucosal changes; lip sealing, and malocclusion (overjet, overbite, and/or posterior crossbite alterations). The quality of oral hygiene was analyzed by the simplified oral hygiene index. The children's mothers also answered a questionnaire about sociodemographic and medical history data. The variables were analyzed descriptively. Female participants were more prevalent (60.5%), and the mean age of the participants was 4.9 years (±1.4) (range: 2-8 years) and 92.1% of their exhibited some oral condition. All participants with CZS-associated microcephaly showed absence of lip sealing and had malocclusion (100.0%). When compared to the other groups, children with CZS had a higher percentage of dental anomalies (35.7%), mucosal changes (71.4%), and unsatisfactory oral hygiene (64.3%). In a sample composed mainly of female participants aged less than 5 years, the prevalence of oral conditions and unsatisfactory oral hygiene was higher in the group with CZS-associated microcephaly, followed by the group with non-CZS-associated microcephaly. Normotypical children had the highest percentage of dental caries experience.

Synthesis of films based on chitosan and protic ionic liquids to be used as wound dressing on the oral mucosa

Oral mucosal ulcerations expose connective tissue to different pathogens and this can progress to systemic infection. This study aimed to synthesize environmentally-friendly films with chitosan and protic ionic liquids, possessing mucoadhesive properties, activity against opportunistic microorganisms, enhanced malleability and mechanical resistance to be used as a wound dressing on the oral mucosa. Therefore, films with chitosan and 10, 35, and 50 % (wt/wt) of 2-hydroxy diethylammonium lactate, salicylate, and maleate protic ionic liquids were synthesized. Thickness measurements and mechanical properties analysis were performed. In addition, oral mucoadhesion, antimicrobial activity, and cytotoxicity properties were investigated. Results showed that the addition of 35wt% and 50wt% of all kinds of protic ionic liquids tested presented significant improvements in film thickness and mechanical properties. Films based on chitosan and the protic ionic liquid 2-hydroxy diethylammonium salicylate at percentages of 35 and 50wt% exhibited superior mucoadhesive properties, antimicrobial activity on opportunistic microorganisms and an improvement in their flexibility after immersion in synthetic saliva. Cytotoxicity results suggest that all kinds of chitosan/protic ionic liquids films tested are safe for intra-oral use. Therefore, the results of this study indicate that these materials could be good candidates for efficient and environmentally-friendly wound dressing films on the oral mucosa.

Disinfectant effectiveness of chlorhexidine gel compared to sodium hypochlorite: a systematic review with meta-analysis

This study aimed to compare the disinfectant ability of chlorhexidine (CHX) gel and sodium hypochlorite (NaOCl). Systematic searches were conducted from inception until December 8th, 2022 (MEDLINE/PubMed, Cochrane Library, Web of Science, Scopus, Embase, and Grey Literature databases). Only randomized clinical trials were included. The revised Cochrane risk of bias tools for randomized trials were used to assess the quality of studies. Meta-analyses were performed. The overall quality of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation tool. Six studies were included. Five had a low risk of bias and 1 had some concerns. Three studies assessed bacterial reduction. Two were included in the meta-analysis for bacterial reduction (mean difference, 75.03 [confidence interval, CI, -271.15, 421.22], p = 0.67; I2 = 74%); and 3 in the meta-analysis for cultivable bacteria after chemomechanical preparation (odds ratio, 1.03 [CI, 0.20, 5.31], P = 0.98; I2 = 49%). Five studies assessed endotoxin reduction. Three were included in a meta-analysis (mean difference, 20.59 [CI, -36.41, 77.59], p = 0.48; I2 = 74%). There seems to be no difference in the disinfectant ability of CHX gel and NaOCl, but further research is necessary.

Analysis of pH, calcium ion release, and energy dispersive spectroscopy of a bioceramic root canal dressing

This study compared the pH and calcium ion release of calcium silicate- (Bio-C Temp) and calcium hydroxide-based (Ultracal XS) medications. Intracanal remnants of both medications were also evaluated using SEM-EDS after the removal protocol. Thirty-five bovine teeth were prepared. Fifteen were filled with Bio-C Temp and 15 with Ultracal XS. Five remained without intracanal medication (control group). Five samples from each experimental time (i.e.. 24, 72, and 168 hours) were used to measure pH and calcium ions release using a digital pH meter and microplate reader, respectively. Afterward, the peaks of the chemical elements composing both medications were analyzed in SEM-EDS. One-way ANOVA and Tukey's post hoc test analyzed the pH and calcium ion release data. Student's t-test compared the medications in each experimental time. SEM-EDS described the percentage of chemical elements in the samples. Bio-C Temp and Ultracal XS showed a significant pH increase from 24 to 168 hours (p<0.05). Ultracal XS showed a higher pH value at 24 hours than Bio-C Temp (p<0.05) but were similar at 72 and 168h (p > 0.05). Calcium ion release did not depend on the experimental period (p > 0.05). Bio-C Temp showed lower calcium ions release than Ultracal XS at 24 hours (p<0.05). SEM-EDS analyses showed the remains of both medications, but the concentration of Si, Al, and W ions was present only in the calcium silicate-based medication. Bio-C Temp presented alkaline pH and a satisfactory calcium ion release over the time. The remaining of both medications were present after the protocols for paste removal.

Oral health status and quality of life of the parental caregivers of children with Down syndrome: A case-control study

The aim of this study was to investigate the oral health status and quality of life (QOL) of the parental caregivers of individuals with Down syndrome (DS), and to evaluate whether there is an association between these variables. The sample of this cross-sectional study was composed by parental caregivers of children with DS (CCDS) and parental caregivers of children without DS (CNDSC). Oral examination was undertaken and a questionnaire was given to participants. QOL was evaluated by WHOQOL-Bref. CCDS presented a higher number of dental prosthesis users and higher gingival bleeding index compared to CNDSC. When oral health was associated with QOL, the use of dental prosthesis was associated with physical domain and the variables having chronic disease and family income were associated with the social domain for both caregivers. The results suggest that caregivers of children with DS have similar oral health and QOL compared to caregivers of children without DS. In both caregivers, oral health status is associated with QOL.

Does the ultrasonic activation of calcium silicate-based sealers affect their physicochemical properties?

This study aimed to evaluate the influence of ultrasonic activation (UA) on the physicochemical properties of hydraulic calcium silicate-based sealers. Nine experimental conditions were created based on the hydraulic calcium silicate-based sealers (Bio-C Sealer, Sealer Plus BC and Bio Root RCS) and the ultrasonic activation (no activation [NA], 10 seconds, and 20 seconds). Then the experimental groups were BC-NA, BC-10, BC-20, SPBC-NA, SPBC-10, SPBC-20, BR-NA, BR-10, and BR-20. Activation was performed with an ultrasonic insert 20/.01. The mold for the physicochemical analysis was filled and evaluated according to the ANSI/ADA specification nº. 57: initial and final setting time, flow, radiopacity and solubility. Tests were also performed to evaluate pH and calcium ion release with experimental periods of 1, 24, 72, and 168 hours with a pH meter and colorimetric spectrophotometer. Data were analyzed by one-way analysis of variance and post-hoc Tukey tests. The significance level was set at 5%. The time of UA progressively delayed the initial setting time for all hydraulic calcium silicate-based sealers (p < 0.05). Twenty seconds of UA increased the mean flow values of Sealer Plus BC and Bio-C Sealer compared to NA (p < 0.05). UA did not influence the radiopacity and solubility of the tested sealers (p > 0.05). UA for 20 seconds enhanced the pH levels and the calcium ion release of Sealer Plus BC and Bio-C Sealer at 168h (p < 0.05). UA for twenty seconds interferes with some physicochemical properties of hydraulic calcium silicate-based sealers.

The effect of coconut sugar on cariogenic traits in streptococcus mutans

Aim: The consumption of foods rich in sugar is linked to several non-communicable diseases, including dental caries. Coconut sugar has systemic benefits due to its lower glycemic indexes (GI) than other table sugars. However, there is currently no data regarding its cariogenic potential. This study aimed to evaluate the effect of coconut sugar on acidogenicity and adhesion of Streptococcus mutans in vitro, compared to sugarcane products. Materials and methods: Aliquots of cultures of S. mutans UA159 were resuspended in a buffer solution enriched with coconut sugar, crystal sugar (refined sugar), and minimally processed sugarcane (demerara light brown sugar and maskavo dark brown sugar), as well as positive (sucrose) and negative controls. The decrease in pH and its corresponding area under the curve (AUC; cm2) were evaluated for the analysis of acidogenicity. S. mutans was incubated in BHI supplemented with each sugar and the percentages of microbial adhesion were calculated. After testing data normality, the one-way ANOVA test (Bonferroni post hoc) was used to compare the AUC and the proportion of adhesion of each group. Results: Regarding the acidogenic potential, statistical differences were found only between the negative control versus all other groups (p<0.001). Likewise, no significant difference in adhesion was found between the tested sugars (p>0.05). Discussion: Although the tested sugars are marketed as “healthy products,” their amount and frequency of usage should be controlled. Conclusion: Coconut sugar presents a similar cariogenic potential to that of sugarcane products when acidogenicity and adhesion are evaluated. Coconut sugar is not indicated as a substitute for sucrose in the control of cariogenic activity.

Caregiving of children with Down syndrome: impact on quality of life, stress, mental and oral health

AIM

Parental caregivers of children with Down Syndrome (DS) have a greater burden of daily activities that may affect their health. The aim of this exploratory study was to evaluate the impact of caregiving of children with Down syndrome on parenting quality of life, stress, mental and oral health.

METHODS

Fifty-four parental caregivers of children with DS and 51 parents of children without physical or mental disabilities participated of this study. All participants were clinically examined to evaluate the presence of dental caries, gingival conditions and answered a sociodemographic questionnaire. Depression, anxiety, quality of life and coping strategies were assessed using specific instruments. Hair cortisol level was assessed as biological marker of chronic stress.

RESULTS

Psychological and quality of life parameters were similar between the groups of caregivers (p > .05). Caregivers of children with DS were older (48.6 vs. 41.5, p < .001), had longer caregiving period (> 10 vs < 10 years, p = .003), presented higher gingival bleeding index (6.1 vs. 4.7, p = .014) and higher cortisol levels (55.9 vs. 38.4, p = .07) as compared with parents of children without disabilities. Sociodemographic data has no influence on cortisol levels (p > .05).

CONCLUSIONS

These findings suggest that the caregiving of children with DS has an impact on parenting oral health and stress.

Avaliação in vitro do potencial antifúngico de sais imidazólicos frente a Candida albicans

Aim: This study aims to evaluate the antifungal potential of imidazolium salts (IS) against Candida albicans. Material and methods: Antifungal evaluation of the IS was performed using the disk diffusion test, using a strain of Candida albicans (ATCC 90028). Five different IS were synthesized and tested in the present study: 1,8-bis(methylimidazolium-1-yl) octane bromide (MImC8MImBr2), 1,12-bis(methylimidazolium-1-yl) dodecane methanesulfonate (MImC12MIm(MeS)2), 1-n-hexadecyl-2,3-dimethylimidazolium chloride (C16DMImCl), 1,10-bis(methylimidazolium-1-yl) decane methanesulfonate (MImC10MIm(MeS)2) e 1,10-bis(methylimidazolium-1-yl) decane bromide (MImC10MImBr2). Cetylpyridinium chloride (C16PyrCl) was used as a reference substance. Chlorhexidine (C34H54Cl2N10O14) and saline (NaCl 0,9%) solutions were positive and negative controls, respectively. Results: Among the tested IS, MImC12MIm(MeS)2, MImC10MIm(MeS)2 and MImC10MImBr2 showed the following values for inhibition halos: 28,00 mm, 20,50 mm and 18,75 mm, respectively. These values were similar or superior than those found for the positive control (14.87 mm) and reference (0 mm) substances. Discussion: IS can be a promising alternative to antifungal conventional therapies, as exemplified in previous studies. However, further in vitro and in vivo studies are needed to assess the antifungal potential of these compounds against Candida-mixed biofilms. Conclusion: Based on these results, there are three in vitro promising antifungal potential against Candida albicans IS tested in this study.

Avaliação do acesso e satisfação aos serviços odontológicos prestados a indivíduos com síndrome de Down na visão de seus pais ou cuidadores

Objetivo: Avaliar o acesso e satisfação aos serviços odontológicos prestados a indivíduos com síndrome de Down (SD) na visão de seus pais ou cuidadores. Materiais e métodos: Participaram do estudo 54 pais ou cuidadores de indivíduos com SD. A coleta de dados foi realizada através de um questionário estruturado contendo perguntas relacionadas às características sócio demográficas do indivíduo com SD, de seu familiar ou cuidador e, também, referentes ao acesso e satisfação em relação ao atendimento odontológico recebido. O questionário foi respondido pelos pais ou cuidadores responsáveis pelos indivíduos com SD. O estudo foi conduzido na cidade de Porto Alegre (RS). Resultados: A grande maioria dos pais ou cuidadores relataram que o filho ou indivíduo cuidado já tinha visitado o dentista. A primeira consulta foi realizada em média aos 5,8 anos, e o principal motivo apontado foi para realizar procedimentos de prevenção. Os serviços públicos foram os mais procurados por essa população, e o tempo para marcar a consulta foi em média uma semana. O atendimento odontológico prestado ao indivíduo foi avaliado pela maioria como bom/ótimo sendo que 97,9% dos entrevistados se considerou satisfeito com o atendimento odontológico oferecido a seu filho ou indivíduo cuidado. Conclusão: Baseado nos resultados do presente estudo, os indivíduos com sindrome de Down tem acesso aos serviços odontológicos e seus pais/cuidadores sentem-se satisfeitos com o atendimento recebido por seus filhos ou indivíduos cuidados.

Genotypic diversity and acidogenicity of Streptococcus mutans in Down syndrome children

AIMS

To evaluate the genotypic diversity and acidogenicity of Streptococcus mutans (S. mutans) and the potential association of these factors with dental caries experience in children with DS compared to non-DS children (controls).

METHODS AND RESULTS

Seventeen children (age 6-12 years) with high salivary S. mutans counts (> 2.5 × 10⁵ CFU/mL) were selected and divided into two groups: DS and non-DS. Five children in each group were caries-free, while the remainder had elevated caries experience. S. mutans isolates were obtained from each participant. The genotypic profile of the isolates was analyzed with the AP-PCR methodology. The acidogenicity of a representative strain from each genotype of S. mutans was also evaluated. DS children had 16 different S. mutans genotypes, while the control group had 21. Twelve genotypes were present in both groups and one of them was associated with caries-free status (P < .05). Although the acidogenicity of the genotypes found in DS children was significantly lower (P < .05) compared to controls, this fact was not associated with caries experience in both groups.

CONCLUSIONS

DS children have a lower S. mutans genotypic diversity and genotypes with lower acidogenicity than those of non-DS children. However these findings were not associated with their caries experience.

Structural Organization of Dental Biofilm Formed in situ in the Presence of Sucrose Associated to Maltodextrin

Maltodextrins, derived from corn starch, have been added to industrialized food combined with sucrose. However it is not clear the diffusion properties of the dental biofilm matrix and the tridimensional structure of multispecies biofilms formed in the presence of these carbohydrates. Therefore, the aim of study was to investigate by confocal laser scanning microscopy (CLSM) the structural organization of the multispecies dental biofilm formed in situ under exposure to sucrose associated to maltodextrin. Adult volunteers wore an intraoral palatal appliance containing bovine enamel blocks. They were instructed to remove the appliance 8 times per day and drop the following solutions on the enamel blocks: deionized distilled water (DDW), maltodextrin, sucrose + maltodextrin or sucrose. Biofilms formed were stained and the percentage of extracellular polysaccharide (%EPS) and thickness were determined by CLSM. Biofilm formed in the presence of sucrose and sucrose + maltodextrin presented similar %EPS and higher than DDW and maltodextrin. Regarding to the biofilm thickness, sucrose and sucrose + maltodextrin treatments were thicker than DDW and maltodextrin and similar between them. The structural organization of the multispecies dental biofilm formed in situ in the presence of sucrose does not change when this carbohydrate is associated to maltodextrin.

Evaluation of Physicochemical Properties of New Calcium Silicate-Based Sealer

Abstract This study aimed to evaluate the physicochemical properties of a calcium silicate-based sealer (Sealer Plus BC; MK Life, Porto Alegre, Brazil) compared with an epoxy-resin sealer (AH Plus; Dentsply DeTrey GmbH, Konstanz, Germany). Initial and final setting time was assessed based on ISO 6876:2012 and ASTM C266:03. Calcium ion release and pH were evaluated by filling polyethylene tubes with sealers and then immersing them in 10 mL of deionized water. Following experimental periods of 1, 24, 72 and 168 hours, the samples were measured regarding pH and calcium ion release with a pH meter and a colorimetric spectrophotometer, respectively. The flow was examined based on ISO 6876:2012. Rings of 10 mm in diameter with 1 mm thickness were prepared to analyze the radiopacity (ISO 6876:2012 and ADA n.57) and solubility (ISO 6876:2012). The data were analyzed by variance analysis, Student-T and Tukey tests (p<0.05). The calcium ion release and pH values were significantly higher for the Sealer Plus BC compared with the AH Plus (p<0.05). Lower setting time, flow and radiopacity were observed for the bioceramic sealer than for AH Plus (p<0.05). Sealer Plus BC exhibited higher solubility compared with AH Plus (p<0.05). Sealer Plus BC showed physicochemical properties as setting time, pH, calcium release, flow, and radiopacity following the required standards, but higher solubility than the minimum values required by ISO 6876:2012.

Fluoride Availability and Stability in Children's Toothpastes in Uruguay

PURPOSE

The purpose of this study was to evaluate the availability and stability of fluoride in children's toothpastes in Uruguay.

METHODS

Six commercial brands of children's toothpaste available in Uruguay were tested. Analyses were made when the dentifrices were purchased (fresh samples) and after one year of storage (aged samples). Total fluoride (TF) and total soluble fluoride (TSF) concentrations were determined using an ion specific electrode.

RESULTS

Four of the children's dentifrices showed TF concentration similar to that specified on the package. Three products showed similar concentrations of TF and TSF with no variations after the one-year storage period. Two dentifrices showed an initial insoluble fluoride concentration greater than 50 percent, which increased with toothpaste aging.

CONCLUSION

Most tested toothpastes showed a decrease in the soluble fluoride content with aging. The high quantity of insoluble fluoride found in two tested dentifrices may compromise their anti-caries efficacy.

A Longitudinal Study of Early Childhood Caries and Associated Factors in Brazilian Children

Abstract Early childhood caries (ECC) affects children all over the world and has high prevalence and severity in preschool children. Different social, biological and behavioral factors compose a network of causal factors for ECC. The aim was to evaluate the association between socioeconomic variables and caries at baseline, and the presence of Streptococcus mutans and Lactobacillus spp. microorganisms with the progression of caries lesions after two years of follow-up in a group of children. At baseline, 163 children (3-4 years old) living in the areas of 12 primary care services of the Hospital Group Conceição (GHC, Porto Alegre, RS, Brazil) were evaluated. After two years, 119 children were re-evaluated. Clinical examinations were conducted by calibrated examiners using the ICDAS criteria. A sociodemographic questionnaire was applied to the children’s parents and saliva samples were collected from the children for microbiological analysis. Descriptive statistics and multivariate Poisson regression analysis were performed in the statistical analysis. The factors associated with the caries progression were marital status of mothers (p=0.040), higher S. mutans counts (p=0.031) and the presence of cavitated lesions at baseline (p<0.001). The caries lesions progression in preschool children enrolled in primary health care was directly associated with marital status, presence of cavitated lesions at baseline and higher S. mutans counts at two-year follow-up.

Dental caries and associated factors in twins with Down syndrome: a case report

Down syndrome (DS) is the most common genetic disorder in humans, but its incidence in monozygotic twins is extremely rare. The aim of this study was to determine the factors associated with dental caries in a pair of monozygotic twin girls with DS, where one had caries experience and the other did not. Clinical examination, salivary Streptococcus mutans (S. mutans) levels and their genotypic diversity, the biochemical composition of the dental biofilm, the frequency of sucrose consumption, and toothbrushing habits were assessed from the twin girls. Twin with caries experience showed higher levels of S. mutans in the saliva and lower concentrations of calcium, phosphate, and fluoride and higher concentrations of extracellular polysaccharides in the biofilm compared to her sister. Genotypic diversity of S. mutans was also higher in the twin with caries experience. Dental biofilm composition showed different patterns of cariogenicity between the two sisters, which may also by itself explain the difference in the dental caries between them.

Biochemical composition of the saliva and dental biofilm of children with Down syndrome

BACKGROUND

The biochemical composition of the saliva and biofilm of children with Down syndrome (DS) may be associated with the incidence of caries in this population.

AIM

To evaluate the biochemical composition of the saliva and dental biofilm of children with DS in the city of Porto Alegre, RS.

DESIGN

The sample comprised 144 children between 6 and 14 years of age, of whom 61 had DS and 83 did not. Stimulated saliva samples were collected from all participants, as were samples of 48-h biofilm. Fluoride (F), calcium (Ca), and phosphorus (Pi ) concentrations in saliva and biofilm were determined by colorimetric method (Ca and Pi ) or selective electrode (F). The level of insoluble extracellular polysaccharide (EPS) in dental biofilm was measured using sulphuric acid method.

RESULTS

Salivary concentration of F, Ca, and Pi did not differ between children with and without DS. The dental biofilm of children with DS, however, showed higher Pi and EPS levels than that of children without the syndrome (P < 0.05).

CONCLUSIONS

The present results suggest that despite the salivary composition being similar between groups, the dental biofilm of children with DS has higher cariogenic potential than that of children without this condition.

Dental caries in individuals with Down syndrome: a systematic review

BACKGROUND

Many studies have shown a lower experience of caries in people with Down syndrome compared to individuals without Down syndrome, but this issue has not been critically evaluated.

AIM

To conduct a systematic review of the international literature on dental caries experience in people with Down syndrome.

DESIGN

Three online databases (PubMed, LILACS, and Cochrane) were used to identify relevant studies on caries experience in people with Down syndrome published until May 2015. PICO (Patient/Population, Intervention, Comparison group, and Outcome) criteria were used to screen studies by title and abstract. An assessment of the methodological study quality was performed according to the modified Newcastle-Ottawa Scale.

RESULTS

The search resulted in 226 studies. Thirteen publications were included in the systematic review. Ten studies reported results of lower caries experience in individuals with Down syndrome in at least one age group studied. Three studies reported no differences in caries experience among the groups. All studies, however, included in this systematic review had limitations that increased the likelihood of bias in the study results.

CONCLUSION

There is no scientific evidence to support the hypothesis that people with Down syndrome have a lower experience of caries than non-syndromic individuals.

Effect of sonic vibration of an ultrasonic toothbrush on the removal of Streptococcus mutans biofilm from enamel surface

PURPOSE

To evaluate in vitro the effect of sonic vibration of an ultrasonic toothbrush in the removal of Streptococcus mutans (S. mutans) biofilm from human enamel.

METHODS

S. mutans dental biofilm was formed in vitro on human enamel blocks coated by salivary pellicle. The blocks were incubated with a suspension of S. mutans at 37°C for 24 or 72 hours. The blocks were divided to one of three conditions according to the different toothbrush action modes: ultrasound plus sonic vibration (U+SV), ultrasound-only (U) and no ultrasound and no sonic vibration (control). Samples were exposed to each mode for 3 minutes with the toothbrush bristles placed 5 mm away from the enamel block surface. The samples were observed by scanning electron microscopy (SEM) and quantification of S. mutans was performed.

RESULTS

U+SV showed lower bacterial counts compared to U and control on the 72 hour-biofilm (P < 0.05). The SEM analysis revealed that U+SV and U disrupted the S. mutans chains in the 24- and 72-hour biofilm.

Oral Health Status and Salivary Levels of Mutans Streptococci in Children with Down Syndrome

PURPOSE

The literature on the oral health status of Down syndrome (DS) patients is controversial. Therefore, the purpose of this study was to assess the oral health status and levels of mutans streptococci (MS) in the saliva of DS children.

METHODS

This study was performed with 60 DS children and 71 non-DS children aged six to 12 years old. Caries experience, plaque index (PI), and gingival bleeding index (GBI) were recorded. Information about oral hygiene habits was obtained. Saliva samples were collected to determine MS levels.

RESULTS

The prevalence of dental caries was similar in children with and without DS. DS children had lower PI and GBI values and a higher toothbrushing frequency. Supervised toothbrushing by parents or guardians was more frequent in DS children and associated with lower PI and GBI. High counts of MS in saliva were associated with caries experience in DS children.

CONCLUSIONS

Down syndrome children had a similar caries experience, lower plaque index, and lower gingival bleeding index values compared to children without Down syndrome. However, DS children who had caries were more likely to display high counts of mutans streptococci in saliva than non-DS children with caries.

Fluoride retention in saliva and in dental biofilm after different home-use fluoride treatments

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.

Factors associated with prevalence of dental caries in Brazilian schoolchildren residing in Japan

Brazilian immigrants comprise the third largest ethnic group within the Japanese population. The aim of this cross-sectional study was to determine the factors associated with the prevalence of dental caries in Brazilian schoolchildren living in Japan. A total of 378 schoolchildren, aged between 6 and 14 years, attending Brazilian schools in Japan were included. Clinical data were collected according to World Health Organization criteria. Socioeconomic data, oral health behavior and diet information were collected through questionnaires. The correlation between associated factors and dental caries prevalence was analyzed using chi-square test and multiple logistic regression analysis. The percentage of caries-free schoolchildren was 61.90% and the mean DMFT was 1.28 ± 2.22 (mean ± SD). The mother's educational level and previous access to dental care services in Brazil were strongly associated with caries experience (P < 0.05). This study indicated that these variables are risk factors associated with caries experience in a community of Brazilian schoolchildren residing in Japan.

Effect of different frequencies of fluoride dentifrice and mouthrinse administration: an in situ study

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.

Effect of different 1% chlorhexidine varnish regimens on mutans streptococci levels in saliva and dental biofilm

PURPOSE

To evaluate in a randomized controlled study the effect of different 1% chlorhexidine (CHX) varnish regimens on levels of mutans streptococci (MS) in saliva and dental biofilm.

METHODS

Subjects with MS < or = 10(5) CFU/ml saliva, 11-16 years old, were allocated into four groups: Group A (n = 14): one 1% CHX varnish application; Group B (n = 14): 1% CHX varnish was applied once daily on 3 consecutive days; Group C (n = 15): 1% CHX varnish was applied three times with an interval of 4 days between each application; and Group D (n = 12): placebo varnish was applied once daily on 3 consecutive days. Saliva and dental biofilm samples were collected at baseline and 1, 4, and 8 weeks after the final varnish application.

RESULTS

After 1 week, a slight reduction in salivary levels of MS in Groups A, B, and C (-0.70, -0.90, and -0.41 log10 CFU/ml saliva, respectively) was observed, significant only in Groups A and B (P < 0.05). No difference in salivary levels of MS was observed between the experimental groups in the different experimental periods. After 1 week in the dental biofilm a significant increase in total bacterial counts was observed in all experimental groups while a significant decrease in the levels of MS was observed only in Group A.

The effect of different formulations of chlorhexidine in reducing levels of mutans streptococci in the oral cavity: A systematic review of the literature

OBJECTIVES

The current study undertakes a systematic review of the literature in order to assess how long different formulations (solutions, gels and varnishes) of chlorhexidine (CHX) reduce the level of mutans streptococci (MS) in the oral cavity.

SOURCES

A search of the PUBMED and LILACS databases was conducted through October 2005.

STUDY SELECTION

Clinical studies evaluating the effects of CHX solutions, gels, or varnishes on MS levels were targeted (n=52).

CONCLUSIONS

The studies varied greatly in quantity of mouthwash solution used in rinsing, length of rinsing, and treatment frequency and period. CHX mouthwash solution had short-term effect on salivary MS. Most of studies evaluating CHX gel and varnish used a concentration of 1%. The 1% CHX gel showed a significant reduction through intensive treatment (3-4 daily applications over 2 days) or through daily application for 10 and 14 days. It cannot be asserted that 1% CHX varnish provides better results when applied intensively as compared to applications conducted at intervals of 1 or more months. Treatment using 1% CHX varnish displays large variations in the level and length of decreased MS levels. Despite variability in results, 40% CHX varnish has a greater effect on the period of decreased MS levels than does 1% CHX varnish. Studies did not show a statistically significant difference between the gel and the varnish. The effects of CHX treatment must be monitored, given sharp individual variability in response to this treatment.

Dental caries prevalence in Brazilian schoolchildren resident in Japan

The Brazilian community in Japan is the third largest of the ethnic groups within the Japanese population. However, the oral health condition of Brazilian schoolchildren resident in Japan has not been documented previously. This study was carried out to assess the prevalence of dental caries in Brazilian schoolchildren resident in Japan. The study population comprised 296 schoolchildren aged 6 to 12 years, attending Brazilian schools in Japan. Clinical examinations were performed by a single qualified examiner. The prevalence of dental caries found in this population was 64.9% (95% IC = 59.39 - 70.34%), the percentage of caries-free children being relatively high at 35.1% (95% IC = 29.7% - 40.6%). The mean decayed (D), missing (M), and filled (F) teeth (T) index at age 12 was 1.75 (95% IC = 1.03 - 2.47), and the mean dmft at age 6 was 3.50 (95% IC = 2.43 - 4.57). The proportion of treated teeth was higher than that of decayed teeth in both dentitions. With regard to the distribution of dental caries experience, only 8.4% of all schoolchildren had a DMFT > 3, suggesting a polarization phenomenon of dental caries in this population. Although the prevalence of dental caries among Brazilian school-children resident in Japan is lower than that of their Japanese counterparts, oral health programs are necessary for those children in whom the disease is prevalent and have higher treatment needs.

Fluoride availability and stability of Japanese dentifrices

The decline of dental caries in the industrialized countries can be attributed to widespread use of fluorides. The Japanese market share of dentifrices containing fluorides has increased from 12% in 1985 to 77% in 2000. For a fluoride dentifrice to be effective in the control of dental caries, an adequate concentration of the fluoride must be soluble. Several Japanese fluoride dentifrices have in their formulations calcium phosphate as an abrasive, which may react with fluoride. This study was designed to evaluate the availability and stability of fluoride in the most consumed dentifrices in Japan. The analyses were made when the dentifrices were purchased (fresh samples) and after one year of storage (aged samples) at room temperature (21.8 +/- 3.6 degrees C). Total fluoride and soluble fluoride was determined using an ion specific electrode. All dentifrices showed similar concentrations of total fluoride in fresh and aged samples in accordance with the Japanese Legislation (content of less than 1,000 ppm F). Some dentifrices, with dicalcium phosphate as abrasive, showed decreasing concentrations of total soluble fluoride and increasing amounts of insoluble fluoride over time. Although most of the Japanese fluoridated dentifrices evaluated in this study contain unstable fluoride, they were found to have sufficient concentrations of soluble fluoride to be effective in preventing dental caries.

Sequence of ultrastructural changes of enamel crystals and Streptococcus mutans biofilm in early enamel caries in vitro

Undecalcified mature enamel sections were used to observe the sequence of ultrastructural changes of enamel crystals and Streptococcus mutans biofilm in the early stages of caries. Human enamel blocks were incubated from 1 to 7 days with S. mutans suspension, and the pH of biofilm was measured. They were processed for light microscopic and transmission electron microscopy observations, and the number of bacteria located in the area adjacent to enamel surface counted. It was observed that the pH of the biofilm dropped to 4, after 1-day of incubation and the S. mutans number increased until 4-day. Round shaped enamel crystals were observed in the 2-day specimens and from the 4-day, images of crystals showing defects and perforations were visualized, becoming more defective along the incubation days. The length of time that the enamel was exposed to biofilm was the main factor for enamel crystals demineralization. Current in vitro caries induction system could standardize time-related changes of the property of Streptococcus mutans biofilm and its relation to enamel crystals demineralization at the ultrastructural level, and thus provide a useful model for the evaluation of the effects of various anti-cariogenic agents.

Effect of dentifrice containing fluoride and/or baking soda on enamel demineralization/remineralization: an in situ study

The additive effect of baking soda on the anticariogenic effect of fluoride dentifrice is not well established. To evaluate it, a crossover in situ study was done in three phases of 28 days. Volunteers, using acrylic palatal appliances containing four human enamel blocks, two sound (to evaluate demineralization) and two with artificial caries lesions (to evaluate remineralization), took part in this study. During each phase, 10% sucrose solution was dripped (3 times a day) only onto the sound blocks. After 10 min, a slurry of placebo, fluoride (F) or fluoride and baking soda (F+NaHCO(3)) dentifrice was dripped onto all enamel blocks. The results showed a higher F concentration in dental plaque formed during treatment with F+NaHCO(3) than placebo (p<0.05), but the difference related to F dentifrice was not significant. The enamel demineralization was lower, and remineralization was greater, after treatment with F+NaHCO(3) than placebo (p<0.05), but the difference related to F dentifrice was not significant. The data suggest that baking soda neither improves nor impairs the effect of F dentifrice on reduction of demineralization and enhancement of remineralization of enamel.