Effect of Root Repair Materials and Bioactive Glasses on Microhardness of Dentin

Introduction: The use of bioactive glasses to re-establish or increase mechanical properties of the root dentin may be an interesting alternative. The aim of this study was to evaluate the effect of root repair materials and bioactive glasses on the microhardness of human root dentin. Methods and Materials: Sixty-four sectioned palatal roots of human molars were prepared and two slices were obtained of the middle third of each root (one corresponding to the control group, without treatment, and the other to the experimental group). The pairs of slices were randomly divided into four groups (n=16). The root canal of experimental slices were filled with one of the following materials: mineral trioxide aggregate (Angelus MTA, Angelus, Londrina, Paraná, Brazil), EndoSequence Root Repair Material (ERRM, Brassler, Savannah, GA, USA), Bioglass (45S5) and an experimental niobophosphate glass (NbG). The specimens were stored in an oven at 37ºC, in an environment with 100% humidity for 60 days. The specimens were subjected to a microhardness test. Four indentations were made at a distance of 20 µm from the root canal lumen. For microhardness analysis, comparing the experimental groups and their respective controls, the Student’s-t test was applied. For comparison of the percentage increase in microhardness between the groups, the data were statistically analyzed by using One-way ANOVA and Tukey’s test. The level of significance was set at 0.05. Results: All the materials significantly increased the dentin microhardness values (P<0.05). MTA showed a higher increase in microhardness (94.8±42.7%), similar to that of EndoSequence (62.3±39.9%). The 45S5 (46.5±30.0%) and NbG (53.8±31.3%) showed the lowest percentages of increase in microhardness, but were statistically similar to those of EndoSequence. Conclusion: All the materials tested were capable of increasing root dentin microhardness.Keywords: Bioactive Glass 45S5; Dental Materials; Hardness Test; Microhardness Tests; Root Canal Filling Material

Calcium Pre-Rinse : effect on permeability of dentin tubules by fluoride rinse

The aim of this study was to evaluate whether calcium (CaL) solution would enhance the capacity of sodium fluoride (NaF) solution in reducing the permeability of hypersensitive dentin. Thirty-two Wistar rats ingested for 45 days acidic isotonic drink (Gatorade, pH 2.7) ad libitum to induce dental erosion. Then, molar teeth received a cold stimulus to confirm the presence and score the intensity of dentin hypersensitivity based on body contraction and noise. Animals were allocated to four groups (n=8), according to the solution(s) applied in the oral cavity: NaF (12 mmol/L, 1 min); CaL (150 mmol/L, 1 min); CaL followed by NaF (CaF+NaF, 1 min each); distilled water (DW, 1 min, as negative control). The animals were euthanized and the mandibles dissected into hemimandibles, which were sealed with sticky wax, except for the occlusal surface of the molar teeth. The samples were immersed in 10% copper sulphate solution and in 1% dithioxamide alcoholic solution (25 min each). The samples were sectioned longitudinally and imaged under optical microscope. Then, dentin permeability was measured as the area of copper ion penetration, using ImageJ software. Photomicrographs were obtained by scanning electron microscopy. 68.7% of animals had body contraction associated or not with noise. One-way ANOVA followed by Tukey´s test indicated that groups treated with NaF solution, whether or not preceded by CaL solution, presented lower permeability than the remaining groups [CaL+NaF: 3405.7 ?m2 (±1796.4); NaF: 4111.7 ?m2 (±2450.6); CaL: 42254.6 ?m2 (±30399.2); DW: 37064.6 ?m2 (±21994.4)]. Photomicrographs showed that CaL+NaF group presented an increased proportion of occluded dentin tubules in comparison to the NaF-only group. Although qualitatively there seems to be a benefit in using CaL pre-rinse, this solution did not quantitatively enhance the capacity of NaF in reducing permeability of hypersensitive dentin

CONHECIMENTOS, ATITUDES E PRÁTICAS DE CUIDADORES INFANTIS SOBRE SAÚDE BUCAL: UMA REVISÃO INTEGRATIVA / KNOWLEDGE, ATTITUDES AND PRACTICES OF CHILDREN'S CAREGIVERS OF ORAL HEALTH: AN INTEGRATIVE REVIEW

Introdução: Os pais e cuidadores infantis desempenham um importante papel no ensino das práticas de saúde bucal das crianças.Objetivo: Realizar uma revisão integrativa acerca dos conhecimentos, atitudes e práticas sobre saúde bucal entre os cuidadoresinfantis. Métodos: A busca na literatura foi realizada através das bases de dados Bireme e Medline, utilizando os termos:“Child”, “Oral Health”, “Health Education”, “Health”, “Caregivers”, “Health Knowledge”, “Attitudes” e “Practice, Dental General”.Pesquisas qualitativas, estudos e séries de casos, revisões de literatura descritiva foram excluídos. Artigos publicados há maisde 10 anos foram excluídos da amostra. Resultados: A busca resultou em 44 artigos, onde destes 36 foram excluídos e 8 selecionados.Conclusão: Diante dos achados encontrados neste estudo, conclui-se que fatores como renda familiar, nível educacional,número de filhos e valores culturais podem influenciar nos conhecimentos, atitudes e práticas sobre saúde bucal de cuidadoresinfantis. Estratégias voltadas para educação continuada dos cuidadores devem ser incentivadas.Palavras-chave: Criança. Saúde Bucal. Cuidadores.AbstractIntroduction: Parents and child caregivers play an important role in the teaching of oral health practices of children. Objective:To conduct an integrative review about the knowledge, attitudes and practices of oral health among children's caregivers. Methods:A literature search was conducted through the BIREME and MEDLINE databases using the key words: "Child," "Oral Health","Health Education", "Health", "Caregivers", "Health Knowledge" "Attitudes" and "Practice, Dental General". Qualitative research,studies and case series, descriptive literature reviews were excluded. Articles for more than 10 years were excluded from thesample. Results: The search resulted in 44 articles, where these 36 were excluded and 8 selected. Conclusion: On the findings inthis study, it is concluded that factors such as family income, educational level, number of children and cultural values mayinfluence the knowledge, attitudes and practices of oral health of children's caregivers. Oriented strategies for continuing educationof caregivers should be encouraged.Keywords: Child. Oral Health. Caregivers

USO DA LUZ NO CLAREAMENTO DENTAL EM CONSULTÓRIO: HÁ CONTROVÉRSIAS? / LIGHT USE IN CLINICAL DENTAL WHITENING: ARE THERE CONTROVERSIES?

Introdução: O clareamento dentário vem sendo bastante popularizado, novos produtos surgem e a luz aparece como forma de acelerar o processo clareador, entretanto a literatura ainda é controversa sobre usar ou não uma fonte de luz externa. Objetivo: Realizar uma revisão crítica da literatura dos últimos dez anos acerca do uso das fontes de luz como estratégia para acelerar e/ou ativar agentes clareadores, tendo como ênfase aspectos referentes à eficácia e possíveis efeitos adversos. Métodos: A pesquisa foi realizada utilizando a base de dados eletrônica Pubmed, para seleção de trabalhos em língua inglesa publicados entre 2004 e 2014, com foco na avaliação do uso de diferentes fontes de luz para ativação de agentes clareadores. A estratégia da pesquisa incluiu a utilização dos termos “Tooth bleaching agents” e “light”. Resultados: Foram identificados 314 artigos. Após a aplicação dos critérios de inclusão/exclusão, 20 trabalhos foram selecionados. Parte dos estudos reportaram melhorias significativas com o uso da luzou apontaram para uma efetividade limitada a curto prazo, enquanto outros não encontraram diferenças entre a utilização ou não da luz. Conclusão: Embora a literatura disponível seja controversa, a utilização de fontes de luz em associação ao clareamento dental de consultório deve ser analisada com cautela, a fim de que não haja riscos envolvidos no uso. Novas pesquisas devem ser realizadas para produção de evidências mais sólidas que condenem ou apoiem sua utilização.Palavras-chave: Agentes Clareadores. Luz. Clareamento Dental.AbstractIntroduction: Tooth whitening has been widely popularized, new products are emerging and light appears as a way to accelerate the whitening process. However, literature is still controversial about whether to use an external light or not. Objective: To review the literature of the last ten years about the use of light sources as a strategy to accelerate and/or activate bleaching agents, with emphasis on aspects concerning effectiveness and possible adverse effects. Methods: The search was performed using the PubMed electronic database, in order to select English-language papers published between 2004 and 2014, focusing on the evaluation of the use of different light sources for activation of bleaching agents. The search strategy included the use of "Tooth bleaching agents" and "light" terms. Results: 314 papers were identified. After inclusion/exclusion criteria application, 20 papers were selected. Some studies reported significant improvements with the use of light, or indicated a limited short-term effectiveness, while others found no difference in the use of light or not. Conclusion: Although the literature is controversial, use of light sources in association with clinical tooth whitening should be analyzed carefully, so that there are no risks involved in their use. New research should be carried out to produce more solid evidence to condemn or support their use.Keywords: Tooth Bleaching Agents. Light. Tooth Bleaching

Impact of Solvent Evaporation and Curing Protocol on Degree of Conversion of Etch-and-Rinse and Multimode Adhesives Systems

Objectives. This study evaluated the effect of air-drying time and light-curing time on the degree of conversion (DC) of three etch-and-rinse adhesive systems: ONE-STEP (OS) and ONE-STEP plus (OSP), Ambar (AMB), and two multimode adhesive systems: All-Bond Universal (ABU) and ScotchBond Universal (SBU) by Fourier transform infrared (FTIR) analysis. Materials and Methods. The DC of each adhesive system was analyzed with six experimental different protocols: (1) immediate light curing for 10 s without solvent volatilization; (2) 10 s solvent volatilization with air stream plus 10 s light curing; (3) 60 s solvent volatilization with air stream plus 10 s light curing; (4) immediate light curing for 20 s without solvent volatilization; (5) 10 s solvent volatilization with air stream plus 20 s light curing; and (6) 60 s solvent volatilization with air stream plus 20 s light curing. FTIR spectra were obtained, and the DC was calculated by comparing the ratio of aliphatic/aromatic double carbon bonds before and after light activation (Bluephase 20i). The DC means were analyzed by three-way analysis of variance (ANOVA) and post hoc Tukey tests (α = 0.05). Results. Three-way ANOVA showed statistically significant adhesive, air-drying, and light-cured time (p<0.001). In general, there was a trend of increased DC when the adhesives were dried and cured for longer times, but that was not observed for all the adhesives tested. The acetone-based adhesive systems require an air-drying prior to light activation. The light-curing time of 20 s increases the DC of all materials tested. Conclusion. The results suggested that the DC of the adhesive systems tested was material dependent. In general, the protocol with solvent evaporation for 10 seconds with air syringe plus 20 seconds of light curing finds the high values of DC

Shear Strength of Brackets Bonded with Universal Adhesive Containing 10-MDP after 20,000 Thermal Cycles

Objectives. The aim of this study was to evaluate the shear bond strength of metal brackets bonded with different universal adhesive systems containing 10-MDP and Transbond Plus Self Etching Primer after 20,000 thermal cycles. Materials and Methods. A total of 130 sound bovine teeth were used, which are divided into 5 groups (n = 26) according to the adhesive system used: All-Bond Universal (Bisco), Ambar Universal (FGM), Clearfil Universal Bond (Kuraray), Single Bond Universal (3M/ESPE), and Transbond Plus SEP (3M/ESPE) as control. The adhesives were applied for 20 seconds and bonded with a resin Transbond XT (3M/ESPE). After this, the teeth were submitted to 20,000 cycles at 5°C and 55°C. Afterwards, the shear bond strength test was performed in a universal test machine (Instron 3342). The adhesive remnant index (ARI) was evaluated under a stereomicroscope at 10x magnification and scanning electronic microscopy (SEM, Hitachi 3030). The shear bond strength data were submitted to One-Way ANOVA (α = 0.05) and the ARI to the Kruskal–Wallis test (α = 0.05). Results. Statistical analysis showed that the universal adhesive systems presented mean shear bond strength values similar to Transbond Plus SEP (p<0.05). The universal adhesive presented similar ARI values among them but differed from those of Transbond Plus SEP (p<0.001). Transbond Plus SEP presented a high ARI value when compared with the universal adhesive systems and high demineralization of enamel. Conclusions. The results show that universal adhesive systems may be used for bonding metal brackets if the orthodontist wants to maintain dental enamel health

Impact of Immersion Media on Physical Properties and Bioactivity of Epoxy Resin-Based and Bioceramic Endodontic Sealers

This study assessed the effects of immersion media [distilled water (dw), phosphate buffered saline (pbs) and simulated body fluid (sbf)] in the physical properties [fluid uptake/sorption/solubility and alkalinization activity (pH)] and bioactivity of a bioceramic sealer: the BioRoot RCS (BioRoot) (Septodont). The epoxy-resin sealer AH Plus (Dentsply) was used as comparison. Sealers were immersed in dw, pbs and sbf to evaluate the fluid uptake/sorption/solubility and pH’s media. Bioactivity was assessed with SEM/EDS, FTIR-ATR and XRD. BioRoot solubility was as follows: sbf > pbs = dw. BioRoot had alkaline pH, and AH Plus had neutral pH, regardless of the medium. BioRoot presented mineral precipitates and peaks indicating hydroxyapatite-precursors in pbs and sbf. AH Plus physical properties were not affected by immersion media and it had no bioactivity. pbs and sbf should be preferred to investigate bioceramic sealers over distilled water, because they were able to highlight the sealer properties. BioRoot maintained the alkaline environment and favored hard tissue deposition