RESUMO O objetivo deste estudo in vitro foi de avaliar a influencia do tempo de tratamento no desempenho de dentifrícios fluoretados nano-encapsulados na remineralizagao de lesoes cariosas iniciáis. Noventa e seis amostras de esmalte humano foram divididas em oito grupos (n = 12): 50% NanoF + 50% NaF livre, 100% NanoF, 100% NaF (controle positivo) e Placebo (controle negativo) com dois tempos diferentes (um e cinco minutos). Após a indugao da lesao cariosa, os espécimes foram submetidos a um modelo de ciclagem de pH por sete dias. A microdureza superficial foi medida antes e após a indugao da lesao cariosa e após o tratamento. O percentual de remineralizagao superficial foi calculado para cada tempo de estudo. Os dados foram analisados pelo ANOVA e ANOVA de medidas repetidas, seguida de Bonferroni (p <0,05). Diferengas de remineralizagao foram observadas nos dentifrícios de acordo com o tempo de tratamento utilizado. Formulagoes NanoF com 50% (tratamento de um minuto) e 100% (tratamento de cinco minutos) promoveram uma remineralizagao do esmalte, após o desafio cariogènico, quando comparado com o dentifricio placebo (p <0,05). Assim, o tempo foi considerado um fator importante para o sistema de liberagao de flúor. A nanotecnologia pode ser um sistema promissor de remineralizagao da cárie, por disponibilizar o flúor por maior tempo na superficie dentària.

ABSTRACT The aim of this in vitro study was to evaluate the influence of treatment time on the remineralization performance of nanoencapsulated fluoride dentifrices on initial carious lesions. Ninety-six human enamel samples were allocated to eight groups (n = 12): 50% NanoF + 50% free NaF, 100% NanoF, 100% NaF (positive control), and placebo (negative control), using two different treatment times (one and five minutes) for each dentifrice tested. After the carious lesion induction, the specimens were submitted to a pH remineralizing cycling model for seven days. Surface microhardness was measured before and after carious lesion induction and after treatment. The percentage of surface remineralization was calculated for each study time. Data were analyzed using two-way ANOVA and ANOVA repeated-measures tests followed by the Bonferroni correction (p < 0.05). Remineralization differences were observed in the dentifrices analyzed according to the treatment time used. NanoF formulations with 50% (one-min treatment) and 100% (five-min treatment) promoted significant remineralization of enamel after the caries challenge when compared to the placebo dentifrice (p < 0.05). Thus, time was considered an important factor for the fluoride release system. Nanotechnology can be a promising system for caries remineralization as it makes fluoride available on the dental surface for a longer time.

The aim of our study was to select the optimal operating conditions to permeabilize Kluyveromyces lactis cells using ethanol as a solvent as an alternative to cell disruption and extraction. Cell permeabilization was carried out by a non-mechanical method consisting of chemical treatment with ethanol, and the results were expressed as β-galactosidase activity. Experiments were conducted under different conditions of ethanol concentration, treatment time and temperature according to a central composite rotatable design (CCRD), and the collected results were then worked out by response surface methodology (RSM). Cell permeabilization was improved by an increase in ethanol concentration and simultaneous decreases in the incubation temperature and treatment time. Such an approach allowed us to identify an optimal range of the independent variables within which the β-galactosidase activity was optimized. A maximum permeabilization of 2,816 mmol L-1 oNP min-1 g-1 was obtained by treating cells with 75.0% v/v of ethanol at 20.0 °C for 15.0 min. The proposed methodology resulted to be effective and suited for K. lactis cells permeabilization at a lab-scale and promises to be of possible interest for future applications mainly in the food industry.

O presente estudo teve como objetivo investigar a prevalencia de anomalias dentarias em um grupo de individuos com diferentes tipos de fissuras que procuraram o servico de referencia em ortodontia no atendimento de fissurados da Paraiba, nordeste do Brasil. O estudo foi do tipo transversal e observacional. Para tanto, foi realizado por dois examinadores previamente treinados (kappa= 0,89) o exame clinico em 76 pacientes portadores de fissuras pos e transforame incisivo unilateral ou bilateral, de ambos os sexos e de 4 a 32 anos, e analise das radiografias periapicais e panoramicas do arquivo dos prontuarios desses pacientes. Apenas os dentes anteriores superiores foram avaliados. Os dados foram submetidos a estatistica descritiva e ao teste estatistico qui-quadrado, sendo significativo ao nivel de 5%. Dentre os individuos examinados, o genero masculino (57,9%) e a fissura transforame incisivo unilateral esquerda (40,8%) foram os mais prevalentes. A maioria dos examinados (73,68%) apresentou pelo menos uma anomalia dentaria, sendo a agenesia (31,6%), seguida pela presenca de dentes conoides (28,9%) as alteracoes mais frequentes. Os dentes mais afetados foram os incisivos laterais e houve diferenca estatistica significativa (p<0,00001) entre a presenca de defeito do lado fissurado e do contralateral. Portanto, maior atencao deve ser dispensada ao diagnostico e tratamento odontologico dos pacientes fissurados, sugerindo-se a associacao do exame clinico e radiografico a um planejamento criterioso e a implementacao de servicos especializados na tentativa de detectar e tratar de forma precoce e correta estes pacientes.

The aim of this study is to investigate the prevalence of dental anomalies in a group of individuals with different types of clefts attending the reference service in orthodontics for the care of patients with clefts in Paraiba state, northeastern Brazil. This was a cross-sectional, observational study. Two previously trained examiners (kappa = 0.89) performed the clinical examination of 76 patients with post and incisive transforamen unilateral or bilateral clefts, of both sexes, aged 4 to 32 years, and the analysis of periapical and panoramic radiographs from archived records of these patients. Only the upper front teeth were evaluated. Data were processed by descriptive statistics and subjected to statistical Chi-square test considered significant at 5%. Among the patients evaluated, males (57.9%) and left unilateral transforamen clefts (40.8%) were prevalent. Of the total 76 patients examined, 56 (73.68%) had at least one dental anomaly, the most frequent being agenesis (31.6%) and conical teeth (28.9%). The presence of anomalies differed significantly between the cleft and the contralateral sides (p<0.00001). The diagnosis and treatment of patients with clefts should therefore receive more attention. It is suggested that clinical and radiographic examination be performed together with careful planning and implementation of specialist services in an effort to provide early and adequate detection and treatment.

O objetivo desta pesquisa foi estimar a toxicidade aguda do extrato do cravo-da-índia (Syzygium aromaticum Linné) em roedores. O extrato hidro-alcoólico a 80% foi concentrado em evaporador rotativo obtendo-se uma mistura final de extrato pilular. Camundongos albinos (Mus musculus) fêmeas, divididos em 13 lotes de seis animais foram observados por 24 horas a partir da administração do extrato diluído em solução fisiológica a 0,9% nas dosagens de 137,5; 180; 187,5; 250; 375; 437,5; 500 e 1.000 mg/kg para via intraperitoneal e 1.000; 2.400; 2.880; 4.000 e 5.000 mg/kg para via oral. O cálculo proporcional foi realizado a fim de se obter a mesma dose para todos os animais de cada grupo. As punções foram por via intraperitoneal sendo respeitados intervalos de cinco minutos entre as administrações individuais. Nos ensaios de toxicidade por via oral a solução foi introduzida no trato digestório dos animais através de cânula metálica acoplada a seringa (gavagem). Os animais apresentaram alguns sinais de toxicidade, porém não letais até a dose de 5.000 mg/kg. A DL50 para via intraperitoneal foi calculada pelo método de Karber e Behrens (1964), sendo estabelecida em 255 mg/kg (muito tóxico, grau 4). Conclui-se que sob condições agudas de exposição, o extrato do cravo-da-índia é um agente tóxico, devendo ser considerado como tal, dependendo da dose administrada ou absorvida, tempo e freqüência de exposição e vias de administração.

The objective of this research was to estimate the acute toxicity of the extract of clove (Syzygium aromaticum Linné) in rodents. The 80% hidro-alcoholic extract was concentrated in rotary evaporator until a final resinous mixture extract was obtained. Albino female mice (Mus musculus), divided in 13 lots of six animals were observed for 24 hours. The extract diluted in 0.9% physiologic solution was administrated at the dosages of 137.5; 180.0; 187.5; 250.0; 375.0; 437.5; 500.0 and 1,000 mg/kg through intraperitoneal route and 1000; 2,400; 2,880; 4,000 and 5,000 mg/kg through oral route. A proportional calculation was carried out in order to have the same dose for the animals in each group. The punctures were gotten by intraperitoneal route in intervals of five minutes among the individual doses. For the oral toxicity the solution was introduced in the digestive system of the animals through coupled metallic stem syringe (gavage). The animals presented non lethal toxic signs up to 5,000 mg/kg. DL50 was established by the method of Karber and Behrens (1964). LD50 was estimated in 255 mg/kg (highly poisonous, degree 4). It can be concluded that under acute conditions of exposure, the extract of clove is a poisonous agent and it should be considered as such, depending on the administered or absorbed dose, time and frequency exhibition and administration routes.

Nesta pesquisa foi avaliada a atividade antimicrobiana e a capacidade de inibição da síntese de glucano in vitro do extrato da casca do fruto da romã (Punica granatum Linn.) sobre linhagens bacterianas de Streptococcus mitis, Streptococcus mutans, Streptococcus sanguis, Streptococcus sobrinus e Lactobacillus casei. Os ensaios foram realizados pelas técnicas de ágar-difusão em placas para determinação da Concentração Inibitória Mínima (CIM) e técnica dos tubos inclinados para determinação da Concentração Inibitória Mínima de Aderência (CIMA) ao vidro, na presença de 5% de sacarose. Os mesmos procedimentos foram realizados com a clorexidina à 0,12%. As CIMs (mg/mL) do extrato da P. granatum frente ao S. mitis, S. mutans, S. sanguis, S. sobrinus e L. casei foram 1:32, 1:8, 1:8, 1:512, e 1:128, respectivamente. Para as CIMAs o extrato da P. granatum mostrou resultados melhores que a clorexidina, exceto para o S. mutans com achados semelhantes na diluição de 1:256. Os resultados mostram a potencialidade da P. granatum na inibição do crescimento bacteriano e síntese de glucano representada pela aderência ao vidro, sugerindo o emprego do extrato da romã, como meio alternativo, no controle desses microrganismos na formação do biofilme.

In this study was evaluated the in vitro antibacterial activity and the inhibition of glucan sintesis of the fruit bark of Punica granatum Linn extract upon the following dental biofilm bacteria: Streptococcus mitis, Streptococcus mutans, Streptococcus sanguis, Streptococcus sobrinus and Lactobacillus casei. The tests were carried out by inundation tecniques in Petri dishes to determine the Minimum Inhibitory Concentration (MIC) and inclined tubes techniques to determine the Minimum Inhibitory Concentration of Adherence to glass (MICA) at the presence of 5% sucrose. Tests with gluconate of chlorexidine (0.12%) were performed as controls. MICs of the P granatum extract dilutions (mg/mL) against S. mitis, S. mutans, S. sanguis, S. sobrinus e L. casei were 1:32, 1:8, 1:8, 1:512, and 1:128 respectively. For MICAs the P. granatum showed better results than chlorexidine, except for S. mutans with both substances showing similar results of 1:256. It can be concluded that the extract of the P. granatum has the potential to inhibit oral bacterial growth and glucan sintesis. The extract of the Punica granatum might be used as an effective antibacterial alternative agent against oral biofilm bacteria.