ABSTRACT Objective: To investigate whether the dimensions of cavitated dentin carious lesions on the occlusoproximal surfaces of primary teeth could predict the location of cement-enamel junction (CEJ). Material and Methods: Two hundred extracted primary molars were selected and digital images were obtained. The teeth were set in arch models for clinical measurement. The cervical-occlusal (CO) and buccal-lingual/palatal (BL/P) cavities’ dimensions were obtained by digital (Image J) and clinical (periodontal millimeter probe) assessments. The cervical margin location was also determined. The thresholds (cut-off points) were determined by sensitivity, specificity and the areas under the receiver operating characteristics curves (Az) for the two methods. Pearson's correlation coefficient was used to investigate the correlation between clinical and digital measurements. Logistic regression analysis was performed to evaluate the association between the dimensions and cervical margin location. Results: There was a strong correlation between methods for all measurements (CO: r=0.90, VL/P: r=0.95). Cavities with BL/P distance higher than 4.5 mm and CO dimension higher than 3.5 mm had a lower chance of presenting the cervical limit above the CEJ, irrespective of the measurement method. Conclusion: CO and VL/P dimensions could be used to predict the CEJ location and, ultimately, as a clinical parameter for restorative decision-making.

Resumo Este ensaio clínico randomizado, duplo-cego objetivou comparar a performance clínica e tempo clínico para restaurar cavidades ocluso-proximais em molares decíduos, restauradas com resina bulk-fill e resina convencional. Um total de 140 restaurações classe II em molares decíduos de 65 participantes (média de idade 6.7 + 1.5) foram realizadas dividas em dois grupos randomizados: resina bulk-fill e resina convencional. As restaurações foram avaliadas conforme o critério da FDI no baseline, após 6 meses e 1 ano, por um único examinador calibrado e o tempo clínico restaurador foi mensurado por um cronômetro digital. O sucesso e a sobrevida das restaurações foram avaliados através dos gráficos de Kaplan-Meier. O teste de log-rank comparou as curvas. A diferença no tempo clínico restaurador foi comparada usando o teste U de Mann-Whitney. O nível de significância foi de 5%. Após 1 ano, 115 restaurações foram avaliadas. A probabilidade de sucesso foi de 88,7% para Filtek Z350 XT e 85.9% para FiltekTM Bulk-fill e quanto a probabilidade de sobrevivência, Filtek Z350 XT apresentou 90% e FiltekTM Bulk-fill apresentou 93,7%. Não foi encontrada diferença significativa entre as curvas de sucesso e sobrevida (p=0,62), (p=0,51). A principal causa de falha foi a adaptação marginal. A resina bulk-fill exigiu 30% menos tempo do que a resina convencional (p<0,001). A resina bulk-fill apresentou desempenho clínico semelhante ao da resina convencional e necessitou menor tempo clínico restaurador. Dessa forma, é uma opção para restaurar lesões classe II em molares decíduos.

Abstract This double-blind, randomized clinical trial aimed to compare the clinical performance and clinical time to restore occluso-proximal cavities in primary molars withbulk-fillresin and conventional resin. A total of 140 class II restorations in primary molars of 65 participants (mean age of 6.7 + 1.5) were placed in two random groups:bulk-filland conventional resin. The restorations were evaluated using FDI criteria at the baseline, 6-month, and one year by a single calibrated examiner, and the clinical restorative time was measured with a digital timer. The success and survival of the restorations were evaluated with Kaplan-Meier graphs. The log-rank test compared the curves. Differences in restorative clinical time were compared using the Mann-Whitney U test. The level of significance was 5%. After one year, 115 restorations were evaluated. The success probability was 88.7% for Filtek Z350 XT and 85.9% for FiltekTM Bulk-fill, and for the survival probability, Filtek Z350 XT presented 90%, and FiltekTM Bulk-fill presented 93.7%. No significant difference was found between the success and survival curves (p=0.62), (p=0.51). The main reason for failure was marginal adaptation.Bulk-fillresinrequired 30% less time than the conventional resin (p<0.001).Bulk-fillresin presented similar clinical performance to the conventional resin and required less restorative clinical time. It is an option to restore class II lesions of primary molars.

RESUMO Objetivo: Mostrar a relação entre a ingestão do açúcar na dieta infantil e a presença da Cárie da Primeira Infância em um grupo de crianças pré-escolares. Métodos: Foi realizada uma análise retrospectiva de prontuários de pacientes de 0 a 6 anos atendidos na Clínica de Bebês entre 2010 a 2016, da Universidade Federal de Santa Maria. Os dados analisados foram: identificação do paciente, sexo, idade, introdução do açúcar (idade e frequência), aleitamento materno exclusivo, uso de mamadeira contendo açúcar, escovação (com ou sem flúor) e diagnóstico de cárie dentária feito através do International Caries Detection and Assessment System. A análise descritiva mostrou as características da amostra e análises comparativas foram realizadas pelos testes de Fisher e T-Student, para verificar a relação entre variáveis individuais e a ingestão de açucares. Resultados: A média de idade das crianças foi de 29 meses. Dos 86 prontuários analisados, 80,0% das crianças ingeriam alimentos açucarados, sendo parte da rotina alimentar. Apenas 36 prontuários continham informações sobre a Cárie da Primeira Infância, nestes foi encontrada uma prevalência de 86,2% da amostra. Não houve diferença estatística entre dieta açucarada e demais variáveis (p > 0,05). Conclusão: Esses resultados sugerem uma intensa relação entre açúcar e Cárie da Primeira Infância. A alta frequência de ingestão de açúcar é um fator de risco para o surgimento da Cárie da Primeira Infância, podendo ser retardada a sua inserção na alimentação infantil. A orientação alimentar e de higienização é fundamental no processo do tratamento assim como a conscientização familiar.

ABSTRACT Objective: To show the relation between sugar intake in the infant diet and the presence of early childhood caries in a group of preschoolers. Methods: A retrospective analysis of medical records of patients aged 0 to 6 years attended at the Clinic of Babies from 2010 to 2016, at Universidade Federal de Santa Maria. The data analyzed were: patient identification, gender, age, sugar introduction (age and frequency), exclusive breastfeeding, use of a bottle containing sugar, brushing (with or without fluoride) and diagnosis of dental caries through the International Caries Detection and Assessment System. Descriptive analysis showed the characteristics of the sample and comparison analyzes were performed using Fisher and T-Student tests, to verify the relation between individual variables and sugary intake. Results: The average age of the children was 29 months. Of the 86 medical records analyzed, 80.0% of the children ingested sugary foods, and its were part of the eating routine. Only 36 medical records contained information about early childhood caries, in which 86.2% of prevalence was found. There was no statistical difference between sugary diet and other variables (p > 0.05). Conclusion: These results suggest an intense relationship between sugar and early childhood caries. The high frequency of sugar intake is a risk factor for the onset of caries in early childhood, and its insertion in infant feeding may be delayed. Food and hygiene orientation is fundamental in the treatment process as well as family awareness.

Abstract Objective: To assess the reproducibility of two clinical criteria for the evaluation of restorations in primary teeth and the impact on treatment decision. Material and Methods: A cross-sectional study was performed selecting 71 resin-based composite restorations placed in primary molars of children who had sought dental treatment at a dental school. Two trained examiners evaluated independently the restorations using modified FDI and USPHS criteria. All restorations were assessed separately with each system in random order to avoid memory bias. Kappa statistics were used to determine inter-examiner reliability considering each parameter of both criteria and score final about treatment decision. McNemar test was used to compare the treatment decision with two criteria. The significance level was set at 5%. Results: Kappa values ranged from 0.28 to 0.93 with USPHS and 0.28 to 0.88 with FDI, considering each parameter separately. Inter-examiner agreement for treatment decision was excellent for both criteria (Kappa: 0.85-0.90). For clinical decision-making, no difference between criteria was found, irrespective of examiner. Conclusion: Low inter-examiner agreement for evaluation of each parameter of USPHS and FDI criteria does not reflect on reproducibility for treatment decision. Both criteria may be suitable for evaluation of composite restorations in primary teeth.

Abstract The aim of this study was to investigate the influence of shortening of etching time for dentin on the restoration survival after selective carious tissue removal in primary molars. This two-arm randomized clinical trial included sixty-two subjects (5–8 year-old) and 100 primary molars presenting moderate dentin carious lesions on occlusal surface. The sample was randomly assigned into groups previously to adhesive application (Adper Single Bond 2; 3M ESPE): etching time recommended by manufacturer (15 s) or reduced (7 s). Resin composite (Filtek Bulk Fill Posterior Restorative; 3M ESPE) was inserted in a single increment for all restorations. Restorations were evaluated at 1, 6, 12, and 18 months using FDI criteria. Survival estimates for restorations’ longevity were evaluated with Kaplan-Meier method. Multivariate Cox regression analysis with shared frailty was used to assess the factors associated with failures (p < 0.05). The etching time did not influence the restorations’ survival (HR 0.35 95%CI 0.11–1.12; p = 0.06). Mean estimated time of survival was 17.6 months (95%CI, 17.2–17.9). The survival rates at the 18-month follow-up were 75.7% and 91.4% (AFR: 16.9% and 5.7%) when primary dentin was acid etched for 15 and 7 s, respectively (log-rank p = 0.06). In conclusion, the etching time for dentin did not influence the clinical behavior of adhesives restorations. However, there was a tendency for better clinical outcome when using etching time of 7 s.

Abstract Objective: To compare the teaching of the pulpectomy in primary teeth among graduate and undergraduate Brazilian dental schools. Material and Methods: From August 2015 to July 2016, an 11-question survey was sent to 44 graduate and 207 undergraduate dental schools. Data obtained were summarized using descriptive statistics. Results: The response rate was higher from graduate (56.8%) than undergraduate (41.1%) courses. Pulpectomy was taught by all participating schools. More than 90% of the undergraduate and graduate courses recommend the use of hand instruments for canals debridement, but the widening of root canals was advised in 69.4% of undergraduate and in 84% of graduate schools. Regarding the irrigatings, 1% sodium hypochlorite as a single irrigating solution was the most taught for both biopulpectomy and necropulpectomy. The iodoform-based Guedes-Pinto paste as the single indication was the preferred root canal filling material in undergraduate schools (30.6%), while the zinc oxide-thickened calcium hydroxide paste as the single option was the most recommended in graduate courses (36%). Endodontic hand file associated with lentulo drill for filling root canals was recommended by most courses. Overall, biopulpectomy was performed in one session, while necropulpectomy led two sessions. Periapical radiograph for diagnosis and final obturation was the most adopted conduct by undergraduate (68.2%) and graduate (72%) schools. Gutta-percha and glass ionomer cement were preferred materials to seal the entrance of the pulp chamber. Conclusion: There was variability in the techniques and materials taught to perform pulpectomy in primary teeth among Brazilian graduate and undergraduate dental schools. Calcium hydroxide paste has been used in similar proportion to iodoform-based paste.

Abstract: This study aimed to evaluate the bond strength of a universal adhesive system to enamel surrounding real-life carious cavities. Twenty-eight permanent molars (n = 7) with carious lesions in dentin were subjected to selective carious tissue removal to firm dentin and had their crowns sectioned longitudinally. A universal adhesive system (Single Bond Universal [SBU] used in either etch-and-rinse and self-etch strategies) was compared with an etch-and-rinse Adper Single Bond 2 (ASB) and a self-etch Clearfil SE Bond (CSE) adhesive systems (control systems). Adhesives were applied on the enamel, assumed demineralized, surrounding the cavity margins and on sound enamel (control substrate). Composite cylinders were built (0.72 mm2) and microshear bond strength (µSBS) test was performed after 24 h of water storage. The µSBS values (MPa) were analyzed using two-way ANOVA and Tukey's post hoc tests (α = 0.05). Bond strength values obtained in demineralized enamel surrounding carious cavity margins were significantly lower than that obtained in sound enamel (distant from carious cavity margins) (p = 0.035). The bonding strategy of the SBU did not influenced the bond strength values, which were higher than that obtained with ASB. CSE showed similar µSBS values to ASB and SBU in the self-etch mode. In conclusion, the bond strength to enamel assumed demineralized is lower than to sound enamel. The enamel surrounding carious cavities jeopardize the bonding of universal adhesive system. The bond strength of universal adhesive is similar, regardless to bonding strategy.

Abstract This study aimed to compare the longevity of different conventional restorative materials placed in posterior primary teeth. This systematic review was conducted following the PRISMA statement and registered in PROSPERO (CRD42016035775). A comprehensive electronic search without date or language restrictions was performed in PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Scopus, Turning Research Into Practice (TRIP) and Clinical Trials databases up to January 2017, selecting randomized clinical trials that assessed the longevity of at least two different conventional restorative materials performed in primary molars. Seventeen studies were included in this systematic review. Pairwise and network meta-analyses were performed and relative risks and 95% confidence intervals (CI) calculated. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. Restorations of primary molars with conventional glass ionomer cement showed increased risk of failure than compomer, resin-modified glass ionomer cement, amalgam, and composite resin. Risk of bias was low in most studies (45.38% of all items across studies). Pediatric dentists should avoid conventional glass ionomer cement for restoring primary molars.

Abstract: This study aimed to systematically review the literature to address the question regarding the influence of different materials in the clinical and radiographic success of indirect pulp treatment in primary teeth. A literature search was carried out for articles published prior to January 2017 in PubMed/MEDLINE, CENTRAL, Scopus, TRIP and ClinicalTrials databases; relevant articles included randomized clinical trials that compared materials used for indirect pulp treatment in primary teeth. Two reviewers independently selected the studies and extracted the data. The effects of each material on the outcome (clinical and radiographic failures) were analyzed using a mixed treatment comparisons meta-analysis. The ranking of treatments according to their probability of being the best choice was also calculated. From 1,088 potentially eligible studies, 11 were selected for full-text analysis, and 4 were included in the meta-analysis. In all papers, calcium hydroxide liner was used as the control group versus an adhesive system, resin-modified glass ionomer cement or placebo. The follow-up period ranged from 24 to 48 months, with dropout rates of 0-25.7%. The material type did not significantly affect the risk of failure of the indirect pulp treatment. However, calcium hydroxide presented a higher probability of failure. In conclusion, there is no scientific evidence showing the superiority of any material used for indirect pulp treatment in primary teeth.

RESUMO Estudos têm demonstrado que, dentre as diversas técnicas que envolvem a fisioterapia respiratória, o treinamento muscular inspiratório (TMI) é essencial na recuperação da função pulmonar e na prevenção de complicações respiratórias. Porém, o efeito do TMI em pacientes submetidos à cirurgia bariátrica ainda é inconclusivo. O objetivo deste estudo foi revisar sistematicamente ensaios clínicos randomizados que avaliaram o efeito do TMI em comparação a TMI sham, fisioterapia convencional (exercícios respiratórios e deambulação precoce) ou nenhuma intervenção na função pulmonar em pacientes submetidos à cirurgia bariátrica. A estratégia de busca foi realizada nas bases de dados PubMed / MEDLINE, Cochrane, TRIP, PEDro e Scopus sem restrição de ano de publicação ou de idioma, conforme a recomendação PRISMA. Dois revisores selecionaram os estudos, extraíram os dados e avaliaram o risco de viés de forma independente. Dos 2.184 estudos potencialmente elegíveis, 2 foram incluídos. O critério do risco de viés foi adaptado e dividido em 9 áreas usando o Handbook da Cochrane. Esta revisão incluiu 62 participantes, sendo 30 alocados para receber dispositivo Threshold® TMI, mas em diferentes períodos, pré-operatório e pós-operatório. O TMI promoveu aumento da pressão inspiratória máxima (PIM) em relação à fisioterapia convencional, mas não foram encontradas diferenças significativas na pressão expiratória máxima (PEM). Os estudos apresentaram baixo e incerto risco de viés. O TMI parece ser o tratamento mais eficaz em comparação à fisioterapia convencional isolada tanto no pré quanto no pós-operatório. No entanto, não há nenhuma evidência sólida para a tomada de decisões clínicas.

ABSTRACT Studies have shown that among the various techniques that involve chest physical therapy, the inspiratory muscle training (IMT) is essential in the recovery of lung function and in preventing respiratory complications. However, the effect of IMT on patients undergoing bariatric surgery is still inconclusive. The aim of this study was to systematically review randomized and controlled trials that assessed the effect of IMT compared with sham IMT, standard physical therapy (breathing exercises and early ambulation) or no intervention in the lung function on patients undergoing bariatric surgery. The search was conducted in PubMed/MEDLINE, Cochrane, TRIP, PEDro and Scopus databases with no publication year or language limits, following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. From 2,184 potentially eligible studies, two studies were included. Bias risk criteria were adapted and divided into nine main areas using the Cochrane Handbook. This review included 62 participants, being 30 allocated to receive Threshold® IMT device, but in different periods: preoperative and postoperative. IMT promoted increased maximal inspiratory pressure (MIP) in relation to standard physical therapy, but no significant differences were found in maximal expiratory pressure (MEP). The studies showed low and unclear bias risk. IMT seems to be the most effective treatment in comparison with standard physical therapy alone in pre- or postoperative period. However, there is no solid evidence for clinical decision-making.

RESUMEN Investigaciones comprobaron que, entre las varias técnicas relacionadas a la fisioterapia respiratoria, el entrenamiento muscular inspiratorio (TMI) es fundamental para la recuperación de la función pulmonar y en la prevención de complicaciones respiratorias. Pero poco se sabe sobre los resultados del TMI en pacientes sometidos a la cirugía bariátrica. El propósito de este estudio es revisar sistemáticamente los estudios clínicos aleatorios que evaluaron los resultados del TMI comparado al TMI sham, fisioterapia convencional (ejercicios respiratorios y deambulación precoz) o ninguna intervención en la función pulmonar en pacientes sometidos a la cirugía bariátrica. Se buscó textos en las bases de datos PubMed / MEDLINE, Cochrane, TRIP, PEDro y Scopus, sin restricción de fecha de publicación ni de idioma según recomienda la PRISMA. Dos revisores eligieron los estudios, recolectaron datos y evaluaron el riesgo de sesgo de forma independiente. De los 2.184 estudios probablemente elegidos, se excluyeron dos. Se adaptó el criterio de riesgo de sesgo y lo dividió en nueve áreas empleando el Manual de Cochrane. En esta revisión participaron 62 personas, siendo 30 de ellas elegidas para recibir el dispositivo Threshold® TMI, pero en momentos distintos, en el preoperatorio y el posoperatorio. A pesar de que el TMI aumentó la presión inspiratoria máxima (PIM) en relación a la fisioterapia convencional, en la presión espiratoria máxima (PEM) no se encontraron diferencias significativas. Los estudios presentaron bajo e incierto riesgo de sesgo. El TMI puede ser el tratamiento más eficaz en comparación con la fisioterapia convencional aislada tanto en el preoperatorio como en el posoperatorio. Pero no se encontraron evidencias concretas en la toma de decisiones clínicas.

Resumo Introdução O aumento da temperatura do adesivo tem sido pesquisado como forma de melhorar a evaporação do solvente, reduzir a viscosidade e melhorar a permeação dos monômeros na dentina. Objetivo Investigar a influência de diferentes métodos de aquecimento na resistência de união à dentina sob um ensaio de microtração de um adesivo de condicionamento ácido total. Material e método Vinte e quatro terceiros molares hígidos foram seccionados transversalmente a fim de expor a superfície plana da dentina. As amostras foram condicionadas ácido fosfórico a 37% e dividido em três grupos (n=8). São eles: 1) Controle - onde o adesivo (Adper Single Bond 2, 3M ESPE) foi aplicado em temperatura normal (25°C); 2) Dispositivo de aquecimento – O adesivo foi aquecido em um dispositivo específico até alcançar a temperatura de 37°C e só então aplicado à dentina; 3) Ar quente – Usou-se jato de ar aquecido a 50°C por 10 segundos a uma distância de 10cm para facilitar a evaporação do solvente. Os espécimes foram restaurados com resina composta (Filtek Z250 A2, 3M ESPE) e preparados para o ensaio de microtração, após 24h de armazenamento em água destilada. Os dados obtidos foram submetidos para análise de variância (ANOVA) e teste de Tukey (p<0,05). Resultado Não houve diferença significativa entre os grupos (p>0,05). As médias da resistência de união para o grupo controle, dispositivo de aquecimento e ar quente foram, respectivamente, 48,5 (± 5,2), 40,35 (± 4,9), e 47,2 (± 5,3). Conclusão Os diferentes métodos de aquecimento não influenciaram significativamente na resistência de união imediata à dentina de um Sistema adesivo de condicionamento ácido total.

Abstract Introduction Increased adhesive temperature has been reported to promote solvent evaporation, reduce viscosity, and improve monomeric permeation into dentin. Objective The aim of this study was to determine the influence of different heating methods on the microtensile bond strength of an etch-and-rinse adhesive to dentin. Material and method Twenty-four caries-free extracted human third molars were transversally sectioned to expose a flat dentinal surface. The samples were etched with 37% phosphoric acid gel and divided into three groups (n = 8): 1) Control - the adhesive system (Adper Single Bond 2; 3M ESPE) was applied at room temperature; 2) Warming device - the adhesive was warmed to 37°C in a custom device before application; and 3) Warm air - the adhesive was warmed to 50°C with an air jet after application on dentin. The specimens were restored with a composite resin (Filtek Z250 A2, 3M ESPE) and prepared for microtensile bond strength testing, after 24 h in water storage. The data were subjected to one-way ANOVA and Tukey's test (p < 0.05). Result There was no significant difference among the groups (p > 0.05). The mean bond strength values in the control, the warming device, and the warm air groups were 48.5 (± 5.2), 40.35 (± 4.9), and 47.2 (± 5.3) MPa, respectively (p = 0.05). Conclusion The different heating methods had no significant influence on the immediate microtensile bond strength of an etch-and-rinse ethanol-based adhesive to dentin.

Este estudo in vitro avaliou a influência de dois dispositivos para aplicação de força de cisalhamento em testes de resistência de união ao microcisalhamento e no padrão de fratura em dentina e esmalte de dentes decíduos. Oitenta molares decíduos foram selecionados e superficies planas em esmalte (40 dentes seccionados no sentido mésio-distal) e dentina (40 dentes seccionados transversalmente) foram obtidas. Ambas as superficies foram abrasionadas para padronização da lama dentinária. Dois sistemas adesivos de condicionamento ácido prévio (Adper Single Bond e XP Bond) foram utilizados. Tubos de polietileno foram colocados sobre as superficies, nas quais já haviam sido aplicados os sistemas adesivos, e preenchidos com resina composta. O teste de resistência de união ao microcisalhamento foi realizado após armazenamento dos espécimes em água (24 h/37 °C) utilizando dois dispositivos para a aplicação das forças de cisalhamento: cisalha côncava (Bisco Shear Bond Tester) e cisalha plana (Kratos Industrial Equipment). O padrão de fratura foi avaliado usando estereomicroscópio. Os dados de resistência de união foram submetidos à ANOVA e o teste quiquadrado foi utilizado para comparar a distribuição dos padrões de fratura (α=0,05). Não foram observadas diferenças estatisticamente significantes entre os grupos, tanto para a resistência de união a dentina e esmalte quanto para o padrão de fratura (p>0,05). O modo de falha predominante foi adesiva/mista. Em conclusão, os dispositivos para aplicação de força de cisalhamento não influenciam os valores de resistência de união, independente do sistema adesivo e substrato.

This in vitro study evaluated the influence of two devices for application of shear load in microshear tests on bond strength and fracture pattern of primary enamel and dentin. Eighty primary molars were selected and flat enamel (40 teeth sectioned mesio-distally) and dentin (40 teeth sectioned transversally) surfaces were obtained. Both surfaces were polished to standardize the smear layer. Two-step etch-and-rinse adhesive systems (Adper Single Bond and XP Bond) were used. Polyethylene tubes was placed over the bonded surfaces and filled with composite resin. The microshear testing was performed after storage in water (24 h/37 °C) using two devices for application of microshear loads: a notched rod (Bisco Shear Bond Tester) or a knife edge (Kratos Industrial Equipment). Failure modes were evaluated using a stereomicroscope. Bond strength data were subjected to ANOVA and chi-square test to compare the failure mode distributions (α=0.05). No significant differences were observed between the groups for dentin and enamel bond strength or fracture patterns (p>0.05). The predominant failure mode was adhesive/mixed. In conclusion, the devices for application of shear loads did not influence the bond strength values, regardless of adhesive system and substrate.

The aim of this in vitro study was to compare the degradation of resin-dentin bonds of an etch-and-rinse adhesive system to primary and permanent teeth. Flat superficial coronal dentin surfaces from 5 primary second molars and 5 permanent third molars were etched with phosphoric acid and bonded with an adhesive system (Adper Single Bond 2, 3M ESPE). Blocks of resin composite (Z250, 3M ESPE) were built up and the teeth sectioned to produce bonded sticks with a 0.8 mm² cross-sectional area. The sticks of each tooth were randomly divided and assigned to be subjected to microtensile testing immediately (24 h) or after aging by water storage (6 months). Data were analyzed by two-way repeated measures ANOVA and Tukey post hoc test (α = 0.05). Failure mode was evaluated using a stereomicroscope (400×). Microtensile values significantly decreased after the 6 months aging, independent of the dentin substrate. In 24 h, the values obtained to primary dentin were lower compared with permanent dentin. This difference was not maintained after aging. Adhesive/mixed failure was predominant in all experimental groups. In conclusion, degradation of resin-dentin bonds of the etch-and-rinse adhesive system occurred after 6 months of water storage; however, the reduction in bond strength values was higher for permanent teeth.

O objetivo deste estudo foi avaliar o efeito do digluconato de clorexidina (CHX) a 2% na resistência de união imediata de adesivo convencional à dentina decídua hígida (H) e afetada pela lesão de cárie (CA) comparada à dentina permanente. Superfícies dentinárias planas de 20 molares decíduos (Dec) e 20 molares permanentes (Perm) foram divididas em 8 grupos experimentais (n=5) de acordo com o tipo de dente (Dec ou Perm), condição da dentina (H ou CA - ciclagem de pH por 14 dias) e tratamento (controle - C ou CHX - aplicação por 60 s de solução de digluconato de clorexidina a 2% após condicionamento ácido). O sistema adesivo (Adper Single Bond 2) foi aplicado de acordo com as instruções do fabricante, seguido da aplicação de resina composta (Filtek Z250). Após 24 h de armazenamento em água, espécimes com área de secção transversal de 0,8 mm² foram preparados para o teste de microtração (1 mm/min). Os dados foram submetidos à Análise de Variância e teste de Tukey para comparações múltiplas (α=0,05). Modo de falha foi avaliado usando estereomicroscópio com aumento de 400×. Tratamento com CHX não resultou em maiores valores de resistência de união do que sem pré-tratamento (C grupos), independente do tipo de dente. Dentes decíduos e dentina afetada apresentaram menores médias de resistência de união em comparação a dentes permanentes e dentina hígida, respectivamente (p<0,05). Predomínio de falha adesiva/mista foi observado para todos os grupos. CHX não influenciou a resistência de união imediata à dentina hígida ou afetada pela lesão de cárie de dentes decíduos e permanentes

The aim of this study was to evaluate the effect of 2% chlorhexidine digluconate (CHX) on immediate bond strength of etch-and-rinse adhesive to sound (SD) and caries-affected (CAD) primary dentin compared with permanent dentin. Flat dentin surfaces from 20 primary molars (Pri) and 20 permanent molars (Perm) were assigned to 8 experimental groups (n=5) according to tooth type (Pri or Perm), dentin condition (SD or CAD - pH-cycling for 14 days) and treatment (control - C or 60 s application of 2% CHX solution after acid etching - CHX). The bonding system (Adper Single Bond 2) was applied according to manufacturer's instructions followed by resin composite application (Filtek Z250). After 24 h water storage, specimens with cross-section area of 0.8 mm² were prepared for being tested under microtensile test (1 mm/min). Data were submitted to ANOVA and Tukey's post hoc test (α=0.05). Failure mode was evaluated using a stereomicroscope at ×400. Treatment with CHX did not result in higher bond strength values than no pre-treatment (C groups), independently of tooth type. Primary teeth and caries-affected dentin showed significantly lower (p<0.05) bond strength means compared with permanent teeth and sound dentin, respectively. Predominance of adhesive/mixed failure was observed for all groups. CHX did not influence the immediate bond strength to sound or caries-affected dentin of primary and permanent teeth.

The aim of this study was to assess the frequency of routine use of dental prophylaxis prior to visual inspection, in order to diagnose caries, by dentists with different lapses of time after graduating time. One hundred and fifty one Brazilian dentists were interviewed in 3 Brazilian cities to determine if they usually remove dental plaque prior to visual inspection for caries diagnosis. The dentists were stratified according to year of graduation. The association between the lapse of time after graduating and the practice of routinely removing dental plaque before clinical examination was tested using the chi-square test with a significance level of 5%. Only 28.5% of the dentists reported that they usually remove dental plaque prior to clinical examination. The dentists who graduated in the last 15 years presented the lowest percentages of plaque removal prior to clinical examination (15.1%), whereas the more experienced dentists reported that they perform prophylaxis more frequently. Of the professionals who graduated from 1960-1975, 23.9% reported that they performed dental plaque removal prior to diagnosis, whereas the figure for those graduating from 1976-1990 was 46.2%. Most of the dentists interviewed reported that they did not remove dental plaque prior to performing visual diagnosis of caries.