Probiotics-containing beverages and dental caries: A systematic review and meta-analysis.

The aim was to evaluate the effect of probiotics-containing beverages on dental caries development by a systematic review and meta-analysis (PROSPERO CRD42021258010). PubMed, Embase, and Web of Science databases were assessed (up to October 2023) for randomized placebo-controlled trials that evaluated the consumption of probiotics-containing beverages having dental caries as endpoint. Risk of bias assessment (Cochrane Handbook) was performed for all studies. Risk ratio (RR), standardized mean difference (SMD) and 95% confidence interval (CI), were calculated for caries prevalence and caries increment, respectively. Meta-analysis was performed. Qualitative analysis of more than 2000 individuals aged from 1 to 84 years (9 studies) showed inconsistent effects of these probiotics-containing beverages. Synthesis of more than 1000 children and adolescents did not demonstrate a statistically significant difference in the proportion of individuals with cavitated lesions (RR 0.60 [95 % CI 0.34 to 1.08]; n = 2), but a significantly smaller increment of both cavitated and non-cavitated carious lesions (SMD -0.23 [95 % CI -0.39 to -0.08]; n = 4) was related to the consumption of probiotics-containing beverages. Certainty of evidence for caries prevalence and caries increment were moderate and low, respectively. Current evidence is not substantial to strengthen the impact of these beverages on caries development.

Hub genes and pathways related to caries-free dental biofilm: clinical metatranscriptomic study.

OBJECTIVE: This study aimed to evaluate the microbial functional profile of biofilms related to caries-free (CF, n = 6) and caries-arrested (CI, n = 3) compared to caries-active (CA, n = 5) individuals. MATERIALS AND METHODS: A metatranscriptomic was performed in supragingival biofilm from different clinical conditions related to caries or health. Total RNA was extracted and cDNAs were obtained and sequenced (Illumina HiSeq3000). Trimmed data (SortMeRNA) were submitted to the SqueezeMeta pipeline in the co-assembly mode for functional analysis and further differential gene expression analysis (DESeq2) and weighted gene co-expression network analysis (WCGNA) to explore and identify gene modules related to these clinical conditions. RESULTS: A total of 5303 genes were found in the metatranscriptomic analysis. A co-expression network identified the most relevant modules strongly related to specific caries status. Correlation coefficients were calculated between the eigengene modules and the clinical conditions (CA, CI, and CF) discriminating multiple modules. CA and CI showed weak correlation coefficient strength across the modules, while the CF condition presented a very strong positive correlation coefficient (r = 0.9, p value = 4 × 10-9). Pearson's test was applied to further analyze the module membership and gene significance in CF conditions, and the most relevant were HSPA1s-K03283, Epr- K13277, and SLC1A-K05613. Gene Ontology (GO) shows important bioprocesses, such as two-component system, fructose and mannose metabolism, pentose and glucuronate interconversions, and flagellar assembly (p-adjust < 0.05). The ability to use different carbohydrates, integrate multiple signals, swarm, and bacteriocin production are significant metabolic advantages in the oral environment related to CF. CONCLUSIONS: A distinct functional health profile could be found in CF, where co-occurring genes can act in different pathways at the same time. Genes HSPA1s, Epr, and SLC1A may be appointed as potential biomarkers for caries-free biofilms. CLINICAL RELEVANCE: Potential biomarkers for caries-free biofilms could contribute to the knowledge of caries prevention and control.

Biofilm dysbiosis and caries activity: a surface or an individual issue?

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

Biofilm dysbiosis and caries activity: a surface or an individual issue?

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

Effect of Stevia rebaudiana Bertoni infusion on enamel demineralization and dental biofilm formation: an in-situ study / Efeito da infusão de Stevia rebaudiana Bertoni na desmineralização do esmalte e na formação do biofilme dental: um estudo in situ

Aim: Stevia rebaudiana Bertoni (Stevia) is a natural non--caloric sweetener that can modify the cariogenicity of biofilms. This study aimed to evaluate the effect of Ste-via infusion in microbial and biochemical composition of biofilms formed in the presence of sucrose and on enamel demineralization. Materials and Methods: In a cross-over design, eleven volunteers wore an intraoral palatal appliance containing 4 slabs of bovine enamel during 3 phases of 7 days each. Sucrose solution (20%) was dripped onto slabs 8 times/day and 0.9% sodium chloride (NaCl), 0.12% chlorhexidine (CHX), or 5% infusion of Stevia were dripped 2x/day. Biofilm formed on the slabs was collected and analyzed for counts of microorganisms (total bacteria, Lactobacilli, Candida spp., and Streptococcus mutans) biochemical composition in terms of soluble and insoluble extracellular polysaccharides and qualitative assessment by scanning electron microscopy. The per-centage of surface hardness loss (%SHL) was determined on enamel slabs taken baseline and post-biofilm Knoop surface hardness values. Results: The % SHL in the CHX treatment was statistically lower in comparison to NaCl (p < 0.05). No differences were found between Stevia and CHX and between Stevia and NaCl. No other difference was found among the experimental groups with respect to the other outcomes. Discussion: Under high carioge-nic conditions resembling frequent exposure to sucrose and absence of mechanical disruption, use of Stevia can neither modify the counts of cariogenic microorganisms nor the concentration of extracellular polysaccharides on in situ formed biofilms. This may have occurred due to the exposure of the biofilm to high sucrose concentration for all treatments and the condi-tion of the microorganism growth in situ, which may hinder the diffusion of substances through the thick biofilm. Conclusion: Biofilm exposed to a high cariogenic challenge and without mechanical disruption is not affected by an infusion of Stevia rebaudiana Bertoni.

Objetivo: A Stevia rebaudiana Bertoni (Stevia) é um adoçante natural não calórico que pode modificar a cariogenicidade de biofilmes. Este estudo teve como objetivo avaliar o efeito da infusão de Stevia na composição microbiana e bioquímica de biofilmes formados na presença de sacarose e na desmineralização do esmalte. Materiais e métodos: Em um desenho cruzado, onze voluntários usaram um aparelho intraoral palatino contendo 4 pla-cas de esmalte bovino durante 3 fases de 7 dias cada. A solução de sacarose (20%) foi gotejada em placas 8 vezes/dia e cloreto de sódio a 0,9% (NaCl), clorexidina a 0,12% (CHX) ou infusão a 5% de Stevia foram gotejados 2x/dia. O biofilme formado nas placas foi coletado e analisado para contagem da composição bioquímica de microrganismos (bactérias totais, Lactobacilos, Candida spp. e Streptococcus mutans) em termos de polissaca-rídeos extracelulares solúveis e insolúveis e avaliação qualitativa por microscopia eletrônica de varredura. A porcentagem de perda de dureza superficial (%SHL) nos blocos de esmalte foi determinada com base nos valores de dureza superficial Knoop tomadas no início e pós-biofilme. Resultados: O % SHL no tratamento CHX foi estatisticamente menor em comparação ao NaCl (p < 0,05). Não foram encontradas diferenças entre Stevia e CHX e entre Stevia e NaCl. Nenhuma outra diferença foi encontrada entre os grupos experimentais em re-lação aos outros resultados. Discussão: Sob condições cariogênicas elevadas que se assemelham a exposição frequente à sacarose e ausência de disrupção mecânica, o uso de Stevia não pode modificar as contagens de microrganismos cariogênicos nem a concentração de polissacarídeos extracelulares em biofilmes formados in situ. Isso pode ter ocorrido devido à exposição do biofilme à alta concentração de sacarose para todos os tratamentos e à condição de crescimento do microrganismo in situ, o que pode dificultar a difusão de substâncias através do biofilme espesso. Conclusão: O biofilme exposto a um alto desafio cariogênico e sem disruptucao mecânica não é afetado por uma infusão de Stevia rebaudiana Bertoni.

Análise da eficácia de dentifrícios clareadores e seus efeitos na superfície dental: um estudo in vitro / Analysis of the effectiveness of whitening dentifrices and their effects on the dental surface: an in vitro study

O clareamento dos dentes pode ser realizado de várias maneiras, em consultório, no âmbito caseiro ou com a utilização de produtos OTC (Over-the-Counter). Dentre esses produtos, existem os dentifrícios clareadores que prometem clarear e prevenir o manchamento dentário. Objetivos: (1) Investigar o potencial clareador e abrasivo de diferentes dentifrícios no esmalte; e (2) avaliar o efeito do dentifrício Oral-B 3D White Perfection® (Oral-B) na prevenção do escurecimento. Materiais e Métodos: Amostras de esmalte bovino foram pigmentadas e escovadas por 14 dias com água (controle negativo) ou com diferentes produtos: Colgate Total 12® (controle), Oral-B, Sensodyne Branqueador Extra Fresh® (Sensodyne) ou Colgate Luminous White Advanced® (Colgate). Oral-B foi testado antes e após pigmentação. As amostras foram avaliadas quanto à cor (espectrofotômetro) e rugosidade superficial (rugosímetro). Para cálculo de alteração de cor (ΔDE00) se utilizou o sistema CIEDE2000. Os dados foram analisados com os testes Kruskal-Wallis, SNK e Mann-Whitney (α=5%). Resultados: O controle negativo apresentou a menor ΔE00 (p<0,05) e o grupo tratado com Sensodyne resultou nos maiores valores (p<0,05). Quanto à rugosidade superficial, não houve diferença significativa entre os grupos avaliados. O dentifrício Oral-B demonstrou efeito protetivo ao manchamento, resultando em menor alteração de cor (p=0,002). Conclusão: Somente o dentifrício Sensodyne apresentou potencial clareador maior que o dentifrício convencional. A escovação prévia com Oral-B reduziu o manchamento dental, embora não tenha prevenido este totalmente de acontecer. Não foram observadas alterações significativas na rugosidade dos dentes após aplicação dos tratamentos, quando comparado ao controle.

Tooth whitening can be performed at the dental office, at-home or upon the use of OTC (Over-the-Counter) pro-ducts. Among the latter, there are whitening toothpastes that promise to bleach and to prevent tooth staining. Objectives: (1) To investigate the bleaching and abrasive potential of different whitening dentifrices to enamel; and (2) to evaluate the effect of Oral-B 3D White Perfection®(Oral-B) toothpaste in preventing staining. Materials and Methods: Bovine enamel samples were stained and brushed for 14 days with water (negative control) or with different products: Colgate Total 12® (control), Oral-B, Sensodyne Branqueador Extra Fresh® (Sensodyne), and Colgate Luminous White Advanced® (Colgate). Oral-B was also tested before and after staining. The samples were tested by their color (spectrophotometer) and surface roughness (profilometer). Color change (ΔDE00) was cal-culated using the CIEDE2000 color system. The data were analyzed using Kruskal-Wallis, SNK, and Mann-Whitney tests (α=5%). Results: The negative control showed the lowest ΔE00 (p<0.05), whereas the group treated with Sensodyne resulted in the greatest color change (p<0.05). For surface roughness, there was not any significant difference among the groups. The Oral-B toothpaste showed a protective effect against staining, resulting in the lowest color change (p=0,002). Conclusion: Only Sensodyne toothpaste showed higher whitening potential than the conventional toothpaste. By using Oral-B prior staining reduced significantly the intensity of staining, although without the complete prevention of this event. Significant differences were not observed after treatment concerning roughness in comparison to the control.

Bacterial analysis of biofilms from tooth root surfaces presenting different caries activity / Análise bacteriológica de biofilmes de superfícies dentárias radiculares apresentando diferentes estágios de atividade de cárie

This study evaluated the numbers and determined the proportion of mutans streptococci and Lactobacillus spp., which are possible relevant cariogenic organisms, in biofilms recovered from lesions at root surfaces with active caries lesions (ARC), inactive caries lesions, and sound root surfaces (SRS). Samples were cultured in MSB agar for mutans streptococci counts, Rogosa agar for Lactobacillus spp. counts, and brain-heart infusion agar for total viable anaerobic counts. After incubation, the number of colony-forming units (CFUs) was determined and compared between groups by the Mann-Whitney U test with a significance level set at 95%. The proportion of counts of mutans streptococci and Lactobacillus spp. in the total viable microorganisms was also analyzed by Chi-square test. Ninety samples (30 from each surface) from 37 patients were cultured and analyzed. The CFU was similar between mutans streptococci and Lactobacillus spp.These species were present in at least half of the samples and no difference was found in the frequency of isolation of these species. Only 6 samples showed a proportion of more than 10% of mutans streptococci; 4 of the samples were from ARC. Most (93%) SRS samples did not contain viable Lactobacillus spp. The data indicate the low counts of mutans streptococci and Lactobacillus spp. in root sur-faces, regardless of the activity of caries lesions.

O estudo analisou contagens e proporções de mutans strep-tococci e Lactobacillus spp., que podem ser microorganismos importantes em lesões de cárie radicular com diferentes atividades. Biofilmes foram coletados em três locais: ARC ­ superfície radicular com lesão ativa de cárie; IRC ­ superfícies radiculares com lesão inativa de cárie; SRS ­ superfícies de raizes hígidas. As amostras foram cultivadas em agar MSB para contagens de mutans streptococci; agar Rogosa para Lactobacillus spp., e agar BHI para contagens de microrganis-mos viáveis anaeróbicos totais. Após a incubação, o número de unidades formadoras de colônias (UFCs) foi determinado e comparado entre os grupos pelo teste de Mann-Whitney U test. O nível de significância foi estabelecido em 95%. A pro-porção de contagem de mutans streptococci e Lactobacillusspp. no total de microrganismos viáveis também foi analisado através do teste de qui-quadrado. Um total de 90 amostras de 37 pacientes foram cultivadas e analisadas: 30 amostras de ARC, 30 de IRC e 30 de SRS. Números de UFC foram seme-lhantes entre os grupos para ambos, mutans streptococci e Lactobacillus spp. Estas espécies estavam presentes em pelo menos metade de todas as amostras e nenhuma diferença foi encontrada na frequência de isolamento dessas espécies dentro dos grupos. Apenas 6 amostras apresentaram mais de 10% de mutans streptococci e 4 foram de ARC. Em relação aos Lactobacillus spp., 93% das amostras não apresentaram proporção dessas bactérias nas SRS. Mutans streptococci e Lactobacillus spp. estão presentes em baixa proporção nas superfícies radiculares, independentemente da atividade das lesões de cárie.

Eficácia de um dentifrício sem flúor no controle de Streptococcus mutans in vitro / Effectiveness of a non-fluoridated dentifrice in control of Streptococcus mutans in vitro

Objetivo: avaliar a eficácia de um dentifrício, que contém em sua composição extratos vegetais e xilitol para inibição de Streptococcus mutans (UA159). Materiais e método: para verificação da atividade antimicrobiana, foram realizados ensaios in vitro de difusão de ágar, baseados na metodologia da norma M2A8 Anvisa. O estudo foi feito utilizando inóculo de 108 UFC/mL da cepa de S. mutans. O princípio básico foi a difusão de uma solução de dentifrício na superfície do ágar a partir de um disco impregnado. O ensaio foi realizado utilizando como controle negativo água deionizada estéril e como controle positivo clorexidina 0,12%, e foram comparados aos dentifrícios Orgânico Natural® e Colgate Total 12®. O resultado foi analisado a partir da medição dos halos de inibição (mm). Resultados: a clorexidina 0,12% teve maior halo de inibição (21,08 ± 1,02), seguida do dentifrício Orgânico Natural® (11,33 ± 4,35) e do dentifrício Colgate Total 12 (3,93 ± 4,67) P<0,05. Conclusão: a inibição da cepa de S. mutans evidenciada neste ensaio in vitro demonstra o potencial antimicrobiano do dentifrício Orgânico Natural®, mesmo como um possível auxiliar no controle do biofilme dental cariogênico. (AU)

Objective: the goal was to evaluate the effectiveness of a dentifrice that has a chemical composition of plant extracts and xylitol to inhibit the Streptococcus mutans (UA159). Materials and methods: based on the methodology of the M2A8 Anvisa standard, in vitro agar diffusion assays were performed to verify antimicrobial activity. The study was carried out using inoculum of 108 CFU / mL of S. mutans strain. The principle was the diffusion of a dentifrice solution on the agar surface, from a disc impregnated therewith. The assay was performed using as a negative control the sterile deionized water, 0.12% chlorhexidine as a positive control compared to Orgânico Natural® and Colgate Total 12® toothpastes. The result was analyzed from the inhibition halos measurement (mm). Results: the chlorhexidine 0.12% had the biggest inhibition halo (21,08 ± 1,02) followed by the Orgânico Natural® dentifrice (11,33 ± 4,35) and the Colgate Total 12® dentifrice (3,93 ± 4,67) P<0,05. Conclusion: the inhibition of the S. mutans strain realized in these in vitro assay by the Orgânico Natural® dentifrice demonstrate the antimicrobial potential of the same as a possible aid in the control of the cariogenic dental biofilm. (AU)

Atividade antimicrobiana de Stevia rebaudiana Bertoni e de adoçantes não calóricos sobre bactérias cariogênicas: estudo in vitro / Antimicrobial activity of Stevia rebaudiana Bertoni and non-caloric sweeteners on cariogenic bacteria: in vitro study

Objetivo: avaliar a atividade antimicrobiana in vitro da planta Stevia rebaudiana Bertoni e de adoçantes não calóricos sobre o crescimento de Streptococcus mutanse Lactobacillus casei, micro-organismos cariogênicos presentes na cavidade bucal. Materiais e método: o estudo foi realizado utilizando as cepas padrões de S.mutans (UA159) e L. casei (ATCC7469). Foram avaliados diferentes compostos não calóricos substitutos dasacarose nas concentrações de 1%, 5% e 10%: eritritol(ER), Fit Sucralose® (SU), Stevita® (ST), solução de Steviarebaudiana Bertoni (SSr) e, como controle positivo,digluconato de clorexidina (DC). A análise do efeito inibitório desses compostos no crescimento das bactériasfoi feita por meio da técnica de difusão em ágar. Resultado:observou-se que existe um efeito inibitório decrescimento de ambos os micro-organismos por parte da SSr e do ER, enquanto os demais adoçantes testa dosnão tiveram efeito inibitório sobre esses micro-organismos.Conclusão: os resultados demonstram que SSR eER apresentam efeito inibidor no crescimento das cepastestadas de S. mutans e L. casei. (AU)

Objective: The study evaluated the in vitro antimicrobial activity of the Stevia rebaudiana Bertoni plant and non-caloric sweeteners on the growth of Streptococcus mutans and Lactobacillus casei, which are cariogenic microorganisms present in the oral cavity. Materials and method: The study was conducted using the standard strains of S. mutans (UA159) and L. casei (ATCC7469). Different non-caloric compounds were evaluated at concentrations of 1%, 5%, and 10%: erythritol (ER), Fit Sucralose™ (SU), Stevita™ (ST), Stevia rebaudiana Bertoni solution (SSr), and chlorhexidine digluconate (CD) as positive control. The inhibitory effect of these compounds on the growth of bacteria were analyzed by the agar diffusion technique. Result: There was a growth inhibition effect for both microorganisms by SSr and ER, whereas the other sweeteners tested had no inhibitory effect on the microorganisms. Conclusion: The results showed that SSr and ER present an inhibitory effect on the growth the strains tested of S. mutans and L. casei. (AU)

Influence of antidepressant drugs on Ecto-nucleotide pyrophosphatase/phosphodiesterases (E-NPPs) from salivary glands of rats.

Xerostomia is commonly caused by antidepressant drugs and ATP can influence the saliva production. Adenosine is the product of extracellular hydrolysis of adenine nucleotides in submandibular gland cells, which occurs by the action of ectonucleotidases. In this study, we have evaluated the effect of three different antidepressants in ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP1-3) activities in cultured cells from salivary glands. Rats received imipramine (10mg/ml), fluoxetine (20mg/ml) or moclobemide (30mg/ml) by oral gavage. The drugs were administered once a day for 14 days. Our results have shown that the hydrolysis of p-nitrophenyl-5'-thymidine monophosphate increased in all treatments. These effects were not consequence of transcriptional control of E-NPP1-3 genes. The results reported here can highlight the importance of ectonucleotidases in the most common side effect caused by antidepressant therapy.

Kinetic and biochemical characterization of an ecto-nucleotide pyrophosphatase/phosphodiesterase (EC 3.1.4.1) in cells cultured from submandibular salivary glands of rats.

The participation of ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP) activity in the nucleotide hydrolysis by salivary gland cells of rats was evaluated using p-nitrophenyl 5'-thymidine monophosphate (p-Nph-5'-TMP) as a substrate for this enzyme. We investigated the biochemical characteristics of this ectoenzyme in cells cultured from submandibular salivary glands of rats. Primary cell cultures demonstrated ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP) activities, which could be observed by extracellular hydrolysis of p-Nph-5'-TMP and other biochemical characteristics such as dependence of metal ions, dependence of pH alkaline and inactivation by a metal ion chelator. The Km value for the hydrolysis of p-Nph-5'-TMP was 280.7+/-34.2 microM (mean+/-S.D., n=4) and Vmax was 721.31+/-225nmol p-nitrophenol/min/mg (mean+/-S.D., n=4). We suggest that E-NPP is co-localized with an ecto-ATP diphosphohydrolase/ecto-NTPDase and an ecto-5'-nucleotidase, since these enzymes probably act under different conditions. It may be postulated that the physiological role for these ecto-enzymes is to terminate the action of the co-transmitter ATP, generating adenosine.

Kinetic characterization of ATP diphosphohydrolase and 5'-nucleotidase activities in cells cultured from submandibular salivary glands of rats.

The participation of ecto-ATP diphosphohydrolase (CD39; ecto-NTPDase) and ecto-5'-nucleotidase (CD73) activities in the nucleotide hydrolysis by salivary gland cells from rats was evaluated. We investigated the biochemical characteristics of these ectoenzymes in cells cultured from submandibular salivary glands of rats. The V(max) for the hydrolysis of ATP, ADP and AMP were 2275+/-153 (mean+/-SEM, n = 4), 941+/-96 (mean+/-SEM, n = 5) and 175+/-5 (mean+/-SEM, n = 5) nmol Pi liberated per min per mg of protein, respectively. The K(m) values for ATP, ADP and AMP were 224+/-8 microM (mean+/-SEM, n = 4), 163+/-15 microM (mean+/-SEM, n = 5) and 117+/-5 microM (mean+/-SEM, n = 5), respectively. The competition plot showed that ATP and ADP were hydrolyzed at the same active site on the enzyme. It may be postulated that the physiological role for this ecto-enzyme cascade is to terminate the action of the co-transmitter ATP, generating adenosine.

Regeneração tecidual guiada: princípios biológicos e cirúrgicos atuais / Guided tissue regeneration: biological and surgical principles

O objetivo deste artigo é fazer uma revisão da literatura e avaliar a situação atual da Regeneração Tecidual Guiada (RTG). Este trabalho está baseado nos princípios biológicos e cirúrgicos da RTG. Faremos uma revisão a respeito das indicações/contra-indicações, princípios biológicos, princípios cirúrgicos e materiais mais utilizados em RTG

Efeito de dois anti-sépticos sobre a formaçäo da placa bacteriana in vivo / Effect of 2 antibacterial solutions on the formation of bacterian plaque in vivo

O presente estudo compara o efeito antiplaca de soluçöes equimolares de CUSO4 e CH a 1,6 mM. Dois grupos de voluntários bochecharam alternadamente CuSO4, CH e placebo durante 3 períodos de 7 dias. Ao final de cada período, os índices de palaca foram medidos e observados os efeitos inibitórios. Ambas as substâncias reduziram de forma semelhante e significativa a placa formada quando comparada ao placebo