Influência do polimento e tipo de solução extrínseca na pigmentação de restaurações de resina composta / Influence of the dental polishing and type of extrinsic solution in the pigmentation of composite resin restorations

Objetivo: avaliar a pigmentação de restaurações de resina composta (RC) submetidas a diferentes métodos de polimento. Materiais e método: foram realizadas restaurações de RC classe V em 80 dentes bovinos, corpos de prova, divididos em dois grupos experimentais: G1, polimento com Ultra-Gloss, e G2, polimento com um sistema que utiliza uma ponta siliconada impregnada com abrasivo, Enhance. Após, todos os grupos experimentais foram submetidos a soluções pigmentantes de café, chimarrão e refrigerante, 2 vezes ao dia, por 5 minutos, num período de 15 dias. Os corpos de prova foram analisados pela coloração da RC através de um colorímetro utilizando o sistema CIE-Lab. Aplicou-se a análise de variância seguida do método de comparação múltipla de Tukey, quando observada diferença significativa entre os corpos de prova. Resultados: os resultados mostraram que houve diferença estatística nos valores de médios (valor-p < 0,05), sugerindo o café com variação mais elevada; também para as variações entre a condição experimental (valor-p < 0,05), com exceção de delta a (valor-p = 0,817). Conclusão: o tipo de método para polimento de restaurações em RC não apresenta associação significativa com a pigmentação do material, sendo que esta está relacionada com o tipo da solução corante e com o tempo de exposição do compósito às pigmentações. (AU)

Objective: to evaluate the pigmentation of composite resin restorations submitted to different polishing methods. Materials and method: Class V composite resin restorations were performed on 80 bovine teeth, specimens, and divided into two experimental groups: G1-polishing with Ultra-Gloss and G2-polishing with a system using a silicon tip impregnated with abrasive, Enhance. Afterwards, all the experimental groups were submitted to pigmenting solutions of coffee, chimarrão and refrigerante, 2 times a day, for 5 minutes, in a period of 15 days. The specimens were analyzed by coloring the composite resin using a colorimeter using the CIE-Lab system. The analysis of variance was applied followed by Tukey's multiple comparison method when a significant difference was observed between the test specimens. Results: The results showed that there was statistical difference in the mean values (p-value <0.05), suggesting coffee with the highest variation; (p-value <0.05), with the exception of delta a (p-value = 0.817). Conclusion: The type of method for polishing restorations in composite resin does not present a significant association with the pigmentation of the material, which is related to the type of the dye solution and the time of exposure of the composite to pigmentation. (AU)

Graduate and Undergraduate Teaching of Primary Tooth Pulpectomy: A Comparison among Brazilian Dental Schools

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 oxidethickened 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.

Bonding of universal adhesive system to enamel surrounding real-life carious cavities

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.

Is there a best conventional material for restoring posterior primary teeth? A network meta-analysis

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.

Microscópio odontológico como uma ferramenta útil para detectar foraminas na furca e no assoalho da câmara pulpar de dentes permanentes / Dental microscope as a useful tool to detect foramina in the furcation and pulp chamber floor of permanent teeth

This study assessed the influence of evaluation methods in the occurrence of foramina in the pulp chamber floor and in the furcation area of molars with complete and incomplete root formation. Methodology: A sample of 360 sound mandibular permanent molars was selected and prepared. A single experienced operator evaluated the whole sample using two methods: clinical inspection (with the naked eye) and dental microscope (at 30x magnification). Chisquare test was used to compare the detection of foramina between evaluation methods in both regions (p<0.05). Results: A limited number of specimens with foramina in the pulp chamber floor was observed, while there were more teeth with foramina in the furcation area, according both methods. The dental microscope identified significantly more molars with foramina in the furcation (p=0.000) and in the pulp chamber floor (p=0.031) than the clinical inspection. Conclusions: The presence of foramina in the furcation region is substantially greater than in the pulp chamber floor, regardless of the evaluation method. The presence of foramina is not influenced by the rhizogenesis stage. The dental microscope is an excellent tool to view dental anatomical details.

Este estudo avaliou a influência dos métodos de avaliação na ocorrência de foraminas no assoalho da câmara pulpar e na área de furca dos molares com formação radicular completa e incompleta. Metodologia: Uma amostra de 360 molares permanentes inferiores hígidos foi selecionada e preparada. Um único operador experiente avaliou toda a amostra utilizando dois métodos: exame clínico (a olho nu) e microscópio odontológico (com aumento de 30x). O teste do qui-quadrado foi utilizado para comparar a detecção de foraminas entre os métodos de avaliação em ambas as regiões (p<0,05). Resultados: Observou-se um número limitado de espécimes com foraminas no assoalho da câmara pulpar, enquanto que havia mais dentes com foraminas na área de furca, de acordo com ambos os métodos. O microscópio odontológico identificou significativamente mais molares com foraminas na furca (p=0,000) e no assoalho da câmara pulpar (p=0,031) do que na inspeção clínica. Conclusões: A presença de foraminas na região de furca é substancialmente maior do que no assoalho da câmara pulpar, independentemente do método de avaliação. A presença de foraminas não é influenciada pelo estágio de rizogênese. O microscópio odontológico é uma excelente ferramenta para ver detalhes anatômicos dentários.

Antimicrobial activity of different filling pastes for deciduous tooth treatment

Guedes-Pinto paste is the filling material most employed in Brazil for endodontic treatment of deciduous teeth; however, the Rifocort® ointment has been removed. Thus, the aim of this study was to investigate the antimicrobial potential of filling pastes, by proposing three new pharmacological associations to replace Rifocort® ointment with drugs of already established antimicrobial power: Nebacetin® ointment, 2% Chlorhexidine Gluconate gel, and Maxitrol® ointment. A paste composed of Iodoform, Rifocort® ointment and Camphorated Paramonochlorophenol (CPC) was employed as the gold standard (G1). The other associations were: Iodoform, Nebacetin® ointment and CPC (G2); Iodoform, 2% Chlorhexidine Digluconate gel and CPC (G3); Iodoform, Maxitrol® ointment and CPC (G4). The associations were tested for Staphylococcus aureus (S. aureus), Streptococcus mutans (S. mutans), Streptococcus oralis (S. oralis), Enterococcus faecalis (E. faecalis), Escherichia coli (E. coli), and Bacillus subtilis (B. subtilis), using the methods of dilution on solid medium – orifice agar – and broth dilution. The results were tested using statistical analysis ANOVA and Kruskal-Wallis. They showed that all the pastes had a bacteriostatic effect on all the microorganisms, without any statistically significant difference, compared with G1. S. aureus was statistically significant (multiple comparison test of Tukey), insofar as G2 and G3 presented the worst and the best performance, respectively. All associations were bactericidal for E. coli, S. aureus, S. mutans and S. oralis. Only G3 and G4 were bactericidal for E. faecalis, whereas no product was bactericidal for B. subtilis. Thus, the tested pastes have antimicrobial potential and have proved acceptable for endodontic treatment of primary teeth.

Evaluation of accessory furcation canals of permanent mandibular molars sing radiography and clearing / Avaliação do canal cavo-interradicular em molares inferiores permanentes através de Rx e diafanização

Purpose: To evaluate the presence of furcation canals of permanent mandibular teeth using radiography and a clearing technique. Methods: The sample comprised 344 extracted mandibular molars. The presence of furcation canals was assessed by a single trained observer using magnifying lens (4x) for the dental radiographs and a dental optical microscope (30x) for the cleared specimens. Scanning electron microscopy (SEM) was used to evaluate morphological differences in the pulp chamber floor. Results: Radiographs showed that 9% of the specimens had radiolucent areas, 2% had an image that suggested a canal, and 89% had no abnormal findings. Clearing techniques did not show any accessory canal. SEM images revealed dentin tubules in recently extracted teeth; the other specimens had small areas with dentin tubules. Conclusion: Radiography was not better than the clearing technique to diagnose furcation canals. The clearing technique can provide three-dimensional visualization of the internal tooth anatomy for in vitro studies.

Objetivo: Avaliar a presença do canal cavo-interradicular em molares inferiores permanentes através de radiografias e diafanização. Metodologia: A amostra foi constituída por 344 molares inferiores re-hidratados, preparados e armazenados individualmente em recipientes de vidro. A presença do canal cavo-interradicular foi investigada por um único operador treinado usando lupa (4x) para as radiografias e microscópio óptico odontológico (30x) para as amostras diafanizadas. Microscopia eletrônica de varredura (MEV) foi usada para verificar diferenças morfológicas do assoalho pulpar. Resultados: A análise radiográfica mostrou que 9% das amostras tinham uma zona levemente radiolúcida, 2% mostravam uma imagem sugestiva, e 89% das amostras não tinham nenhuma evidência. Pela diafanização, o canal não foi encontrado nas amostras avaliadas. Pela MEV, as amostras recém extraídas mostraram com canalículos dentinários uniformes; as demais apresentaram pequenos sítios com canalículos uniformes. Conclusão: O exame radiográfico não foi o melhor método de diagnóstico; a diafanização é um excelente método avaliativo, pois permite a visualização tridimensional da anatomia interna dental em pesquisas in vitro.