Virulence of Streptococcus mutans : an intrafamilial cohort study on transmission of genotypes

The main aims of this cohort study were to measure the intrafamilial risk of transmission, sharing and stability of the most virulent S. mutans genotypes. A total of 392 clinical isolates of S. mutans obtained from caries-active adults and genotyped to evaluate their transmissibility over time. After extraction of the chromosomal DNA, PCR were performed to detect the genes involved in the production of GbpA (gbpA) and mutacin types I, II, III and IV (mutAI, mutAII, mutAIII and mutAIV). The gbpA, mutAI, mutAII, mutAIII and mutAIV genes were detected in 77.3, 12.5, 51, 16.6 and 89.8% of S. mutans isolates, respectively. The virulence of S. mutans was associated with its transmission (P< 0.01) and stability (P = 0.01), with the most virulent genotypes having higher transmissibility (RR = 1.83, 95% CI 1.44 to 2.32) and higher stability in the oral cavity (RR = 1.52, 95% CI 1.06 to 2.19). Genotypes with the genetic information to synthesize GbpA and mutacins present an important ecological advantage in the process of colonization by S. mutans; they remain stable among the oral microbiota of the host and favor intrafamilial transmission

Avaliação in vitro da microinfiltração marginal em restaurações de amálgama associadas a adesivo dentinário, cimento de ionômero de vidro e verniz cavitário, utilizando diferentes métodos de avaliação

Este trabalho avaliou, in vitro, a microinfiltração marginal de restaurações de amálgama associadas ao verniz cavitário Copalite - Cooley & Cooley (GI - CP), ao adesivo dentinário OptiBond Solo - Kerr (GII - OS) e ao CIV Vitremer - 3M (GIII - VT). Foram utilizados 45 pré-molares que receberam preparos cavitários independentes classe II nas faces mesial e distal, envolvendo as cristas marginais. Todas as cavidades foram restauradas com a liga Dispersalloy - Dentsply. Posteriormente, os dentes sofreram termociclagem e foram armazenados em solução de fucsina básica a 0,5% por 24 horas. As avaliações foram realizadas através de um microscópio óptico com aumento de 150 vezes e no software Sigma Scan, utilizando linha única e linhas segmentadas. A análise dos dados obtidos permitiu constatar que nenhum dos materiais foi capaz de eliminar a microinfiltração marginal, sendo que o GI - CP apresentou valores maiores e estatisticamente significantes (pThis in vitro study evaluated the marginal microleakage of amalgam restorations associated with the cavity varnish Copalite - Cooley & Cooley (GI-CP), dentin adhesive OptiBond Solo - Kerr (GII-OS) and the glass ionomer cement Vitremer - 3M (GIII-VT). Forty-five premolars were employed, which were submitted to independent class II preparations at the mesial and distal aspects comprising the marginal ridges and were restored with Dispersalloy - Dentsply. Afterwards, the teeth were thermocycled and stored in 0.5% basic fuchsine for 24 hours. The evaluations were conducted on a light microscope with 150x magnification and on the Sigma Scan software with employment of a single line and segmented lines. Data analysis allowed to establish that none of the materials was able to eliminate the marginal microleakage, having the GI - CP presented greater and statistically significant values in relation to the other groups in all evaluation methods (

Periodontopatógenos na saliva e placa subgengival de um grupo de mães

The aim of this study was to assess the periodontal condition and the presence of putative periodontal pathogens in 30 Brazilian mothers, aging 21-40 years (28.4 ± 4.49 years), and in their children, aging 5-6 years, since mothers can be a source of pathogens and, thus, influence their children's bacteriological and clinical condition. Besides assessing the plaque index (PI), gingival index (GI) and pocket probing depth (PD), the survey analyzed four subgingival dental plaque samples from mothers and children, as well as a sample of stimulated saliva from mothers. Those samples were analyzed by means of the slot immunoblot (SIB) technique, in order to determine the presence of Actinobacillus actinomycetemcomitans (Aa), Prevotella nigrescens (Pn), Porphyromonas gingivalis (Pg) and Treponema denticola (Td). The mean values and standard deviations of the evaluated clinical variables for mothers and children were, respectively: 1.86 ± 0.67 and 1.64 ± 0.68 for PI, and 1.24 ± 0.67 and 0.82 ± 0.37, for GI. Only for mothers, the total PD was 1.81 ± 0.69 mm, and the PD of four sites was 4.03 ± 1.40 mm. The Wilcoxon test revealed significant difference (p < 0.05) between mothers and their children only as to GI. The most prevalent bacteria in mothers were, in decreasing order: Aa, Pn, Pg and Td. The children presented patterns of oral hygiene and bacterial profiles similar to those of their mothers, in spite of the fact that most of them did not present enough subgingival plaque for testing. The comparison between mothers' subgingival dental plaque and saliva samples revealed statistically significant differences (p < 0.05) for all bacteria, with greater positivity and scores in the saliva, which demonstrates that it is an indicator of oral colonization and can work as a vehicle for the transmission of periodontopathogens from mothers to their children.Procurou-se avaliar a condição periodontal e a presença de periodontopatógenos em 30 mães brasileiras, com idades entre 21-40 anos (28,4 ± 4,49 anos) e seus filhos, com 5-6 anos de idade, considerando que elas possam ser fonte de transmissão para seus filhos e influenciar suas condições clínicas e bacteriológicas. Além de determinar o índice de placa (IP), índice gengival (IG) de mães e filhos, e a profundidade de sondagem periodontal (PS), apenas das mães, avaliaram-se quatro amostras de placa dental subgengival de mães e filhos e uma amostra de saliva total estimulada das mães para a presença de Actinobacillus actinomycetemcomitans (Aa), Prevotella nigrescens (Pn), Porphyromonas gingivalis (Pg) e Treponema denticola (Td), pela técnica de "slot immunoblot" (SIB). As médias e desvios-padrão para as variáveis clínicas em mães e filhos foram, respectivamente: 1,86 ± 0,67 e 1,64 ± 0,68, para o IP e 1,24 ± 0,67 e 0,82 ± 0,37, para o IG, enquanto apenas nas mães, a PS total foi 1,81 ± 0,69 e a PS dos 4 sítios, 4,03 ± 1,40. O teste de Wilcoxon revelou diferença significante (p < 0,05) entre mães e filhos apenas para o IG. As bactérias mais prevalentes nas mães, em ordem decrescente, foram, Aa, Pn, Pg e Td. As crianças demonstraram padrão de higiene oral e de ocorrência bacteriana semelhante aos de suas mães, apesar da maioria delas não apresentar quantidade suficiente de placa subgengival.A comparação entre amostras revelou diferença estatisticamente significante (p < 0,05), com a saliva sempre exibindo os maiores valores e maior positividade, demonstrando ser um indicador de colonização oral e poder funcionar como veículo para a transmissão de periodontopatógenos de mães para filhos

Evaluation of the microleakage of restorative materials in deciduous teeth

Analisou-se a infiltração marginal nas paredes cervical e oclusal de cavidades classe V, preparadas na face vestibular de 40 caninos decíduos extraídos e restauradas com os materiais Chelon-Fil, Vitremer, Compoglass-F e Z100. Compararam-se ainda dois métodos de avaliação da penetração do corante no teste de infiltração: escore e medida linear até a parede da câmara pulpar. Os espécimes passaram por ciclagem térmica de 500 ciclos nas temperaturas de 5 e 55ºC, foram imersos em solução de fucsina básica a 0,5% por 24 horas e seccionados para visualização da infiltração marginal nas paredes cervical e oclusal. Observou-se que o Chelon-Fil apresentou maior grau de infiltração que os demais materiais. Vitremer, Compoglass-F e Z100 apresentaram infiltração semelhante. O Chelon-Fil e o Vitremer apresentaram infiltração maior na parede cervical que na oclusal, fenômeno este que não ocorreu com o Compoglass-F e a Z100, que apresentaram infiltração semelhante em ambas as paredes. Não houve diferença entre os métodos de avaliação da penetração do corante (p < 0,01).The microleakage of Chelon-Fil, Vitremer, Compoglass-F and Z100 was evaluated in deciduous teeth. Class V restorations were placed in the buccal aspect of 40 extracted primary canines; they were thermocycled, and immersed in 0.5% basic fuchsin. Three slices of each tooth were obtained in order to analyze the penetration of dye in the gingival and occlusal walls, under magnification of 40 X. The results showed that Chelon-Fil had the highest degree of marginal leakage. Vitremer, Compoglass-F and Z100 presented similar penetration of dye. The microleakage of Chelon-Fil and Vitremer was greater in the gingival wall than in the occlusal wall. Microleakage was the same in both gingival and occlusal walls when cavities were filled, either with Z100 or with Compoglass-F

Perfil de tratamento de urgência de crianças de 0 a 15 anos atendidas no serviço de urgência odontológica da Faculdade de Odontologia de Bauru, Universidade de São Paulo

Dental recordings of 0 to 15-year-old patients assisted at Urgency Dental Service (UDS) from Bauru Dental School, University of São Paulo, in 2001 and 2002, were assessed in order to quantify the number of patients that used the service, to determine attendance patterns, and to record the frequency of different types of dental emergencies and their performed treatment. Data were plotted and submitted to a descriptive statistical analysis. Among the total of patients attended at UDS (6020), 1166 (19.37%) were children, with mean age of 9.24 years. Trauma was the cause for 199 (17.06%) of the recorded urgency visits. It occurred more frequently in children between 0 and 3 years of age (34.42%), and between 7 and 12 years of age (18.12%). The main treatments performed were temporary restoration (33.33%) for coronal fracture, and orientation (24.44%) for luxation. Nontraumatic events were the etiology for 967 (82.92%) of the total urgency diagnosis. The most commonly found nontraumatic diagnosis was dental caries lesions (61.75%), followed by problems of eruption or root resorption (14.27%) and bone or soft tissue lesions (6.51%), among others (17.47%). The most frequent treatments performed for caries lesions were: excavation and temporary restoration (39.39%) when there was no abscess, and coronal opening and dressing (40.95%) for caries lesions with abscess. There was an increasing trend in caries lesions prevalence according to the rising of the age, in contrast to trauma prevalence. Treatment for both situations was done according to the indicated protocol for each case.Prontuários odontológicos de crianças de 0 a 15 anos de idade atendidas no Setor de Urgência Odontológica (SUO) da Faculdade de Odontologia de Bauru, Universidade de São Paulo, em 2001 e 2002, foram avaliados a fim de se quantificar o número de pacientes que utilizaram o serviço, determinar os padrões de atendimento e relatar a freqüência de diferentes tipos de emergências odontológicas e dos tratamentos realizados. Os dados foram tabulados e submetidos a uma análise estatística descritiva. Do total de pacientes atendidos no SUO (6020), 1166 (19,37%) eram crianças, com média de idade de 9,24 anos. Lesões traumáticas foram responsáveis por 199 (17,06%) do total de visitas de emergência. Isso ocorreu mais freqüentemente em crianças entre 0 e 3 anos (34,42%), e entre 7 e 12 anos (18,12%). Os principais tratamentos realizados foram restauração temporária (33,33%) para fratura coronária, e orientação (24,44%) para luxação. Eventos não-traumáticos foram responsáveis por 967 (82,92%) do total de diagnósticos de emergência. O diagnóstico mais comumente encontrado foi cárie dentária (61,75%), seguida por problemas de irrupção e reabsorção óssea (14,27%) e lesões em tecido duro ou mole (6,51%), entre outros (17,47%). Os tratamentos realizados com maior freqüência para os casos de cárie foram: escavação e restauração temporária (39,39%) quando não havia abscesso, e abertura coronária e curativo (40,95%) para cáries com abscesso. Houve uma tendência para o aumento na prevalência de cárie com a idade. O oposto foi observado para traumatismo dentário. O tratamento para ambos estava de acordo com o preconizado para este tipo de serviço

Evaluation of marginal microleakage and depth of penetration of glass ionomer cements used as occlusal sealants

OBJETIVE: the aim of this study was to conduct an in vitro comparison of marginal microleakage (MM) and the depth of penetration (DP) of glass ionomer cements (GIC) and a resin sealant (RS) into occlusal pit and fissures. METHODS: for that purpose, 60 intact third molars were equally distributed to 5 groups: G1 - 37% phosphoric acid / Delton; G2 - 40% polyacrylic acid / Ketac-Molar / nail varnish; G3 - Fuji Plus conditioner / Fuji Plus/ nail varnish; G4 -37% phosphoric acid / Vitremer / Finishing gloss; G5 -37% phosphoric acid / Vitremer prepared with a 1:4 ratio of powder / Finishing gloss. The teeth were submitted to a thermal treatment corresponding to 300 cycles (15 sec, 5/55(0)C), followed by complete coating with nail varnish, except for 1mm beyond the contour of the sealant. Afterwards, the teeth were immersed in 0.5% basic fuchsine for 24 hours. Thereafter, the teeth were sectioned in buccolingual direction and microscopically analyzed (150x magnification) by means of predetermined scores. The results were subject to the Kruskal-Wallis test. RESULTS: there was no statistical difference between the materials tested in relation to the DP, being that all groups displayed nearly complete filling of the fissures. No sealant material was able to prevent dye penetration; however, the GICs provided better results of MM, with significant difference when compared to the RS. CONCLUSION: all materials investigated presented a satisfactory degree of penetration into the fissures; however, the glass ionomer cements displayed better performance in the marginal microleakage test compared to the resin sealant.OBJETIVO: o objetivo deste estudo foi comparar in vitro a microinfiltração marginal (MM) e o grau de profundidade de penetração (DP) de cimentos de ionômero de vidro (CIV) e um selante resinoso (SR) em fossas e fissuras oclusais. MATERIAIS E MÉTODOS: para tanto, 60 terceiros molares hígidos foram igualmente distribuídos em 5 grupos: G1- ácido fosfórico 37%/Delton; G2- ácido poliacrílico 40%/Ketac-Molar/esmalte cosmético; G3- Fuji Plus conditioner/Fuji Plus/ esmalte de cosmético; G4 - ácido fosfórico 37%/Vitremer/Finishing gloss; G5- ácido fosfórico 37%/Vitremer diluído na proporção de 1/4 de pó/Finishing gloss. Os dentes foram submetidos a um tratamento térmico correspondente a 300 ciclos (15 seg, 5/ 55(0)C), seguindo da total cobertura com esmalte cosmético, exceto 1mm além do contorno do material selador, sendo então imersos em solução de fucsina básica 0,5%, por 24 horas. Posteriormente, os dentes foram seccionados vestíbulo-lingualmente, e avaliados microscopicamente (aumento 150X), por meio de escores pré-determinados. Os resultados foram submetidos ao Teste de Kruskal Wallis. RESULTADOS: não houve diferença estatística entre os materiais testados em relação à DP, sendo que todos os grupos apresentaram um preenchimento quase total das fissuras. Nenhum material selador foi apto em impedir a penetração da solução corante, entretanto, os CIVs promoveram os melhores resultados de MM, distinguindo-se significantemente em relação ao SR. CONCLUSÃO: Todos os materiais testados apresentaram um grau de penetração satisfatório no interior das fissuras, no entanto, os cimentos de ionômero de vidro demonstraram melhor comportamento no teste de microinfiltração marginal, quando comparado ao selante resinoso

Efeito do jato de bicarbonato de sódio sobre o esmalte bovino e posterior efeito remineralizador da saliva

PURPOSE: The aim of the present study was to evaluate the alterations of surface microhardness and wear caused by the sodium bicarbonate jet on bovine enamel and the further remineralizing effect of artificial saliva. METHODS: Fifteen enamel samples (4,0mm x 4,0mm) were used, which constituted the groups: no treatment (MI); treatment with sodium bicarbonate jet (MII and DI); treatment with sodium bicarbonate jet and immersion in saliva for one hour (MIII and DII), 24 hours (MIV and DIII) and 7 days (MV and DIV). Microhardness tests were carried out using a microdurometer in groups M and wear tests by a rugosimeter in groups D. The data were assessed by the one criterion variance analysis and Tukey test. RESULTS: The mean value of microhardness, in KHN, in groups MI, MII, MIII, MIV and MV were 359,80; 335,46; 369,20; 377,73 and 341,86, respectively, whereas the mean values in µm, of wear for group DI, DII, DIII and DIV were 0,564; 0,519; 0,441 and 0,428, respectively. CONCLUSIONS: The sodium bicarbonate jet caused a wear and a reduction in microhardness on the enamel surface; saliva promoted the recovery of initial condition surface microhardness and reduced the wear; the repairing effect of saliva on the surface microhardness alterations occurred within one hour of treatment, having no significant statistical difference from the effect obtained in 24 hours; the best saliva repairing effect on the wear occurred with treatment of 24 hours.OBJETIVO: A finalidade do trabalho foi avaliar as alterações da microdureza e o desgaste provocado pelo jato de bicarbonato de sódio em esmalte bovino e o posterior efeito remineralizador da saliva artificial. MÉTODOS: Utilizaram-se 15 espécimes de esmalte (4,0mm x 4,0mm) que constituíram os grupos: sem tratamento (MI); tratamento com jato de bicarbonato de sódio (MII e DI); tratamento com jato de bicarbonato de sódio e imersão em saliva artificial por uma hora (MIII e DII), 24 horas (MIV e DIII) e sete dias (MV e DIV). Foram realizados testes de microdureza com um microdurômetro nos grupos M e testes de desgaste com um rugosímetro nos grupos D. RESULTADOS: Os dados foram avaliados pela Análise de Variância a um critério e pelo Teste de Tukey. O valor das médias da microdureza, em KHN, nos grupos MI, MII, MIII, MIV e MV foram 359,80; 335,46; 369,20; 377,73 e 341,86; respectivamente, enquanto que os valores médios, em µm, do desgaste para o grupo DI, DII, DIII e DIV foram 0,564; 0,519; 0,441 e 0,428, respectivamente. CONCLUSÕES: o jato de bicarbonato de sódio causou desgaste e diminuição da microdureza superficial; a saliva promoveu o retorno da microdureza superficial à condição inicial e reduziu o desgaste; o efeito reparador da saliva sobre as alterações na microdureza superficial já ocorreu com uma hora de tratamento, não havendo diferença estatisticamente significante do efeito obtido com 24 horas; o melhor efeito reparador da saliva sobre o desgaste ocorreu com 24 horas de tratamento

Efeito da profilaxia profissional e da escovação com dentifrício com ou sem flúor na remineralização do esmalte dental

An in situ evaluation of the potential rehardening effect of fluoridated and non-fluoridated toothpastes with or without air polishing was conducted. Ten volunteers, using acrylic palatal appliances containing two bovine enamel blocks with artificial carious lesions, took part in this study. Four times a day, after the main meals and at night, the volunteers, in a habitual way, brushed their natural teeth with the dentifrice indicated to the experimental design and after that the appliances were put again into the mouth. They were divided into 4 different groups: G1 - control - non-fluoridated dentifrice; G2 - fluoridated dentifrice; G3 - non-fluoridated dentifrice, but having a previous prophylaxis using air polishing; G4 - fluoridated dentifrice and previous air polishing. The effects of treatments on enamel rehardening were evaluated in the blocks that were assessed by surface microhardness, and the percentage of surface microhardness change (%reh) was calculated in relation to the baseline values. The results showed that %reh was higher in the groups with fluoridated dentifrice, and professional prophylaxis did not have an additional effect in the groups of fluoridated dentifrices (pO objetivo deste estudo foi avaliar, in situ, o potencial de remineralizaçaão do dentifrício fluoretado ou não, isoladamente ou associado à profilaxia profissional com jato de bicarbonato de sódio, em esmalte bovino com lesão superficial artificial de cárie. Utilizou-se 80 blocos de esmalte (4X4X2mm), nos quais foram realizadas medidas de microdureza superficial antes e após a desmineralização artificial e após o tratamento, com um penetrador, Knoop carga de 50/7s, para o cálculo do percentual de recuperação de dureza (%reh). Após as tomadas das 2 medidas de microdureza iniciais (antes e após a desmineralização), os blocos de esmalte foram incluídos em dispositivos intrabucais palatinos (2 blocos/aparelho). Dez jovens voluntários usaram estes dispositivos durante 10 dias com intervalo de 7 dias entre cada fase do experimento (estudo cruzado), realizando higiene bucal habitual (4X/dia, sendo 3 após as refeições e 1 à noite). Estabeleceu-se 4 grupos: G1-controle-escovação com dentifrício sem flúor; G2-escovação com dentifrício fluoretado; G3-antes da instalação do dispositivo realizou-se uma profilaxia com jato de bicarbonato de sódio e escovação com dentifrício sem flúor; G4-profilaxia e dentifrício fluoretado. A análise de variância (ANOVA, p=1,04 x 10-6) e o teste de Student-Newman-Keuls (

Pit and Fissure Sealants with Different Materials: Resin Based x Glass Ionomer Cement – Results after Six Months

Objective: To compare the retention and superficial characteristics between a new resin-modified glass ionomer sealant and resin sealant. In addition, the teeth sealed were compared to partially erupted first molars (control group) without sealing in relation to the incidence of dental caries. Material and Methods: Initially, 31 children aged 6-8 years participated in this study. The study children showed caries history, but had at least two healthy first molars. A total of 114 teeth were randomly divided into three groups: Clinpro (n=36), Fluroshield (n=38), and control (n=40). The two sealants were applied under relative isolation after previous prophylaxis and enamel etching with phosphoric acid 35% (15s). Clinical evaluation was performed by two calibrated examiners. They evaluated the retention and surface characteristics of the occlusal surface. Results: Fluroshield® showed significantly greater retention than ClinproTM Varnish® XT (p=0.002). However, the performance analysis of the success and failure of retention presented no significant difference between the materials (p=0.141). Concerning to the surface characteristics, Fluroshield performed better than Clinpro after analyzing the marginal deterioration, marginal discoloration, and superficial discoloration (p<0.05). The surface texture of the materials under study was similar (p=0.071). Sealed groups (Clinpro=Fluroshield) showed similar performance in the prevention of dental caries, which was significantly lower than that of control group (p=0.001). Conclusion: Both sealants, Fluroshield® and Clinpro TM Varnish® XT were effective in preventing caries lesion within 6 months, although Fluroshield sealant showed better clinical retention

Scanning electron microscopic study of the in situ effect of salivary stimulation on erosion and abrasion in human and bovine enamel

This in situ study investigated, using scanning electron microscopy, the effect of stimulated saliva on the enamel surface of bovine and human substrates submitted to erosion followed by brushing abrasion immediately or after one hour. During 2 experimental 7-day crossover phases, 9 previously selected volunteers wore intraoral palatal devices, with 12 enamel specimens (6 human and 6 bovine). In the first phase, the volunteers immersed the device for 5 minutes in 150 ml of a cola drink, 4 times a day (8h00, 12h00, 16h00 and 20h00). Immediately after the immersions, no treatment was performed in 4 specimens (ERO), 4 other specimens were immediately brushed (0 min) using a fluoride dentifrice and the device was replaced into the mouth. After 60 min, the other 4 specimens were brushed. In the second phase, the procedures were repeated but, after the immersions, the volunteers stimulated the salivary flow rate by chewing a sugar-free gum for 30 min. Enamel superficial alterations of all specimens were then evaluated using a scanning electron microscope. Enamel prism core dissolution was seen on the surfaces submitted to erosion, while on those submitted to erosion and to abrasion (both at 0 and 60 min) a more homogeneous enamel surface was observed, probably due to the removal of the altered superficial prism layer. For all the other variables - enamel substrate and salivary stimulation -, the microscopic pattern of the enamel specimens was similar