Efficacy of ClinproTMXT Varnish surrounding brackets on the enamel surface of white spot lesion

Abstract Orthodontics patients usual develop demineralization and present cavity caries lesions after six months. Minimally invasive procedures have been the goal in modern dental practice. The aim of this study was to evaluate the effect of ClinproTMXT Varnish, on the enamel surface roughness and severity of white spot lesions. Twenty premolars were submitted to bond brackets and experimental induction of demineralization and randomly divided into 2 groups: GI - fluoride varnish (Colgate Duraphat®); GII - Ionomeric Sealant (ClinproTMXT Varnish). The treatment was applied around the brackets. The surface roughness of specimens was analyzed, before treatment and 12 weeks after treatment by laser confocal microscopy, and the severity of the white spot lesion was by laser fluorescence device. The data were analyzed by non-parametric Wilcoxon and Mann-Whitney Test, at 5% significance, roughness percentage reduction was performed. The severity of demineralization decreased in both, GI (p = 0.005) and GII (p = 0.019). Enamel superficial roughness levels decreased in GI and GII. As well as the roughness percentage, being more expressive in the ClinproTMXT Varnish group (85,09%). Colgate Duraphat® or Clinpro™ XT Varnish reduced the severity of the demineralization and decreased the superficial roughness on the enamel. The Clinpro™ XT Varnish was superior to superficial roughness on enamel.

Resumo Pacientes ortodônticos geralmente desenvolvem desmineralização e apresentam lesões de cárie após seis meses de tratamento. Procedimentos minimamente invasivos têm sido o objetivo na prática odontológica moderna. O objetivo deste estudo foi avaliar o efeito do ClinproTM XT selante ionomérico, ao redor do bráquete, com relação a rugosidade superficial do esmalte e a severidade da lesão induzida. Vinte pré-molares foram submetidos a colagem de bráquetes e indução experimental de desmineralização e divididos aleatoriamente em 2 grupos: GI - verniz fluoretado (Colgate Duraphat®); GII - Selante Ionomérico (ClinproTM XT). O tratamento foi aplicado ao redor dos bráquetes. A rugosidade da superfície dos espécimes foi analisada, antes do tratamento e 12 semanas após o tratamento por microscopia confocal a laser e severidade da lesão de mancha branca por dispositivo de fluorescência a laser. Os dados foram analisados pelo teste não paramétrico de Wilcoxon e Mann-Whitney, a 5% de significância. A taxa de redução da lesão foi calculada. A severidade da desmineralização diminuiu tanto no GI (p = 0,005) quanto no GII (p = 0,019). Os níveis de rugosidade superficial do esmalte diminuíram no GI e GII, assim como o percentual de rugosidade, sendo mais expressivo no grupo ClinproTMXT (85,09%). Colgate Duraphat® e Clinpro™ XT reduziram a severidade da desmineralização e diminuíram a rugosidade superficial do esmalte. O selante ionomérico Clinpro™ XT foi superior na redução percentual de rugosidade.

Subcutaneous tissue reaction and gene expression of inflammatory markers after Biodentine and MTA implantation

Abstract The aim of this study was to evaluate the subcutaneous connective tissue response of isogenic mice exposed to tricalcium silicate (Biodentine) and aggregated mineral trioxide (ProRoot MTA). A total of 120 mice were divided into 4 groups in 3 different experimental periods (7, 21 and 63 days): Biodentine; Pro-Root MTA; zinc oxide-eugenol and; Negative control - Sham. After the experimental periods microscopic descriptive, semi-quantitative and quantitative analysis of the inflammatory process were analyzed on H&E sections and evaluation of the gene expression of Il10, Infg, Il6, Il1r1 and Tnf (qRT-PCR) were performed. The data obtained were analyzed using the chi-square test and two-way analysis of variance (ANOVA) followed by the Bonferroni post-test (5% significance level). Results: In the microscopic analysis, a slight inflammatory infiltrate was observed, with a predominance of sparse macrophages and polymorphonuclear cells, slight tissue fibrosis, regular fibrous capsule and with dystrophic calcifications, in all groups that received the materials (Biodentine and Pro-Root MTA). In parallel, all materials modulated the gene expression of the different cytokines and receptors evaluated. Conclusion: Pro-Root MTA and Biodentine showed a tissue compatibility, mediated inflammation, with increased fibrous tissue and production of pro- and anti-inflammatory cytokines.

Resumo Objetivo: Avaliar a resposta do tecido conjuntivo subcutâneo de camundongos isogênicos expostos à Biodentine™ e ao Trióxido Mineral Agregado (MTA). Métodos: Um total de 120 camundongos foram divididos em 4 grupos e 3 períodos experimentais diferentes (7, 21 e 63 dias): Biodentine™ (Septodont, Saint Maur des Fosses, França); Pro-Root MTA (Dentsplay, Tulsa, EUA); óxido de zinco eugenol (Biodinâmica Química e Farmacêutica LTDA., Ibiporã, PR - Brasil); e controle negativo - Sham. Após os períodos experimentais, análises microscópicas descritivas, semiquantitativas e quantitativas do processo inflamatório foram analisadas nos cortes de H&E e ainda, foi realizada a avaliação da expressão gênica de Il10, Infg, Il6, Il1r1 e Tnf (qRT-PCR). Os dados obtidos foram analisados por meio do teste do qui-quadrado e da análise de variância (ANOVA) two-way, seguido do pós-teste de Bonferroni (nível de significância de 5%). Resultados: Na análise microscópica observou-se discreto infiltrado inflamatório, com predomínio de macrófagos esparsos e polimorfonucleares, leve fibrose tecidual, cápsula fibrosa regular e com calcificações distróficas, em todos os grupos que receberam os materiais (Biodentine ™ e Pro-Root MTA). Paralelamente, todos os materiais modulam a expressão gênica das diferentes citocinas e receptores avaliados. Conclusão: Pro-Root MTA e Biodentine™ mostraram compatibilidade tecidual, inflamação mediada, com aumento do tecido fibroso e produção de citocinas pró- e antiinflamatórias.

Tissue response after subcutaneous implantation of different glass ionomer-based cements

Abstract The aim of this study was to evaluate the subcutaneous connective tissue response of isogenic mice after implantation of different glass ionomer-based cements (EQUIA® Forte Fil, EQUIA® Fil and Ketac™ Universal Aplicap™). Eighty-seven isogenic BALB/c mice were allocated in 12 groups, 9 were considered as experimental groups (Ketac, E. Fil and E. Forte at 7, 21 and 63 days) and 3 controls (empty polyethylene tubes at 7, 21 and 63 days). After the experimental periods, the subcutaneous connective tissue surrounding the implanted material was removed and subjected to histotechnical processing and staining with hematoxylin and eosin. A histopathological description of the tissue reaction surrounding each material and a semi-quantitative analysis of collagen fiber formation and inflammatory infiltrate were performed. Additionally, the thickness of the granulomatous tissue in contact with each material was measured. Data were analyzed statistically (α=0.05) by the Kruskal-Wallis test, followed by Dunn post-test. Initially, the collagen fiber formation was not different among all the tested materials (p>0.05) but was different at 21 days with the control group presenting the most advanced stage of collagen fiber formation. At 63 days, EQUIA® Forte Fil group showed the most advanced stage of collagen fiber formation, compared to EQUIA® Fil group (p<0.05). The inflammatory infiltrate was not different among the tested materials in any experimental period (p>0.05). The thickness of the granulomatous tissue was greater in the E. Forte group, compared to control in all periods. All glass ionomer-based cements showed tissue compatibility, according to the evaluated parameters.

Resumo O objetivo deste estudo foi avaliar a resposta subcutânea do tecido conjuntivo de camundongos isogênicos após o implante de diferentes cimentos à base de ionômero de vidro (EQUIA® Forte Fil, EQUIA® Fil e Ketac ™ Universal Aplicap ™). Oitenta e sete camundongos isogênicos BALB/c foram alocados em 12 grupos, 9 como grupos experimentais (Ketac, E. Fil e E. Forte aos 7, 21 e 63 dias) e 3 controles (tubos de polietileno vazios aos 7, 21 e 63 dias). Após os períodos experimentais, o tecido conjuntivo subcutâneo ao redor do material implantado foi removido e submetido ao processamento histotécnico e coloração com hematoxilina e eosina. Uma descrição histopatológica da reação tecidual envolvendo cada material e uma análise semi-quantitativa da fibrose e infiltrado inflamatório foram realizadas. Além disso, foi realizada a mensuração da espessura do tecido granulomatoso em contato com cada material. Os dados foram analisados estatisticamente (α=0,05) pelo teste de Kruskal-Wallis, seguido do pós-teste de Dunn. Inicialmente, a fibrose não foi diferente entre todos os materiais testados (p>0,05), mas foi diferente aos 21 dias, com o grupo controle apresentando o estágio mais avançado de fibrose. Aos 63 dias, o grupo EQUIA® Forte Fil apresentou o estágio mais avançado de fibrose, comparado ao grupo EQUIA® Fil (p<0,05). O infiltrado inflamatório não foi diferente entre os materiais testados em nenhum período experimental (p>0,05). A espessura do tecido granulomatoso foi maior no grupo E. Forte, comparado ao controle em todos os períodos. Todos os cimentos à base de ionômero de vidro apresentaram compatibilidade tecidual, de acordo com os parâmetros avaliados.

Adhesion and Initial Colonization of Streptococcus mutans is Influenced by Time and Composition of Different Composites / La Adhesión y la Colonización Inicial de Streptococcus mutans están Asociadas al Tiempo y la Composición de Diferentes Compuestos

ABSTRACT: The aim of this study was to evaluate the adhesion and initial colonization of S. mutans on the surface of novel composite resins during three experimental periods. Biofilms were formed on specimens of Enamel Plus HRI (Hri), FiltekTM Silorane (Si), Tetric EvoCeram® Bulk Fill (Te), KaloreTM (K), and FiltekTM Z250 (Z) (n=4/experimental period). After 4, 8 and 24 hours, the specimens were assessed for bacterial colony forming unit (CFU/mm2) levels and scanned by electron microscopy. All material surfaces showed a similar susceptibility to bacterial adhesion at 4 hours (p>0.05). The amount of microorganisms in the formed biofilms increased at 8 hours for all groups (p<0.05) and decreased at 24 hours only for Te and Z groups (p<0.05). After 24 h, the K group showed higher microorganism counts compared to the other groups. All composite resins evaluated were susceptible to adhesion by streptococci. However, bacteria attachment was not sufficient to maintain S. mutans colonization on Tetric EvoCeram® Bulk Fill and FiltekTM Z250 composites. Composite K presented the highest mean values for bacterial adhesion. Also, it was observed that the composition of resins could interfere with colonization mechanisms.

RESUMEN: El objetivo de este estudio fue evaluar la adhesión y la colonización inicial de S. mutans en la superficie de nuevas resinas compuestas durante tres períodos experimentales. Las biopelículas se formaron en muestras de Enamel Plus HRI (Hri), FiltekTM Silorane (Si), Tetric EvoCeram® Bulk Fill (Te), KaloreTM (K) y FiltekTM Z250 (Z) (n = 4 / período experimental). Después de 4, 8 y 24 horas, las muestras se evaluaron para determinar los niveles de la unidad formadora de colonias bacterianas (UFC / mm2) y se escanearon por microscopía electrónica. Todas las superficies del material mostraron una susceptibilidad similar a la adhesión bacteriana a las 4 horas (p> 0,05). La cantidad de microorganismos en las biopelículas formadas aumentó a las 8 horas para todos los grupos (p <0,05) y disminuyó a las 24 horas solo para los grupos Te y Z (p <0,05). Después de 24 horas, el grupo K mostró mayores recuentos de microorganismos en comparación con los otros grupos. Todas las resinas compuestas evaluadas fueron susceptibles a la adhesión por estreptococos. Sin embargo, la unión de bacterias no fue suficiente para mantener la colonización de S. mutans en los compuestos Tetric EvoCeram® Bulk Fill y FiltekTM Z250. El compuesto K presentó los valores medios más altos para la adhesión bacteriana. Además, se observó que la composición de las resinas podría interferir con los mecanismos de colonización.

Luting agents differentially modulate inflammation and matrix metalloproteinases in connective tissue

Objective: The objective of this study was to evaluate the tissue response and expression of matrix metalloproteinases (MMP) -2 and -9 to resinous and glass ionomer cements in direct contact with the subcutaneous connective tissue. Methods: RelyXTM Unicem resinous cement (RC; n=30), KetacTM Cem Easymix glass ionomer cement (GI; n=30), and polyethylene empty tubes (control; n=30) were implanted in the dorsal subcutaneous tissue of isogenic BALB/c mice, and the tissues were biopsied after 7, 21, and 63 days for histological analysis. The inflammatory cells and fibroblasts were counted, and the fibrous capsule thickness was measured. MMP -2 and MMP-9 expression levels were investigated by immunohistochemistry. Data were analyzed statistically (significance level=5%). Results: We found that RC induced a low inflammation at day 7 and 21, which was increased at day 63 (p<0.05). GI induced a more intense mononuclear inflammatory response at day 7 and 21 (p<0.05), which was reduced at day 63 to levels similar to the control (p>0.05). The fibrous capsule thickness was thin for RC, GI, and control (p>0.05).MMP-2 was detected early for GI and RC and decreased afterwards. MMP-9 presented a similar pattern for GI, whereas the MMP -9 expression was late for RC. Conclusion: Resinous cementRelyXTM Unicem induced an inflammatory response and late MMP -9 expression in the subcutaneous connective tissue that was different from that induced by KetacTM Cem Easymixglass ionomer cement.

Objetivo: Avaliar a resposta tecidual e a expressão de metaloproteinases da matriz (MMP) -2 e -9 frente a um cimento resinoso e um cimento ionomérico, após implantação no tecido conjuntivo subcutâneo de camundongos. Métodos: O cimento resinoso RelyXTM Unicem (CR; n=30), o cimento ionomérico KetacTM Cem Easymix (CI; n=30) e tubo de polietileno vazio (controle; n=30) foram implantados no tecido subcutâneo dorsal de camundongos isogênicos BALB/c e os tecidos removidos para análise histológica após 7, 21 e 63 dias. Foram analisadas a resposta celular local, por meio da contagem de células inflamatórias e a espessura da cápsula fibrosa. A expressão de MMP -2 e -9 foi investigada por meio de imunohistoquímica. Os dados foram submetidos à análise estatística (α=5%). Resultados: Foi observado que CR induziu uma inflamação leve aos 7 e 21 dias com aumento do número de células inflamatórias aos 63 dias (p<0,05). CI induziu uma resposta inflamatória mononuclear mais intensa aos 7 e 21 dias (p<0,05), com redução do infiltrado aos 63 dias, semelhante ao observado no controle (p>0,05). Em todos os grupos a espessura da cápsula foi considerada fina (p>0,05). MMP -2 foi detectada em períodos precoces para CR e CI, com diminuição com o passar do tempo. MMP -9 apresentou um padrão semelhante ao controle para o CI, enquanto para o CR houve aumento com o passar do tempo. Conclusão: O cimento resinoso RelyXTM Unicem induziu uma resposta inflamatória e a expressão de MMP -9 mais tardia no tecido conjuntivo subcutâneo que foi diferente da resposta induzida pelo cimento ionomérico KetacTM Cem Easymix.

Cytotoxicity and cytokine expression induced by silorane and methacrylate-based composite resins

ABSTRACT The successful use of composite resins in Dentistry depends on physicochemical properties, but also on the biological compatibility of resins, because of the close association between pulp and dentin. Objective The aim of this study was to evaluate cytotoxicity and cytokine production induced by light-cured or non-light-cured methacrylate-based and silorane composite resins in RAW 264.7 macrophages. Material and Methods Cells were stimulated with the extracts from light-cured or non-light-cured composite resins. After incubation for 24 h, cytotoxicity was assessed with the lactate dehydrogenase (LDH) and methyl thiazolyl tetrazolium (MTT) assays, and total protein was quantified using the Lowry method. TNF-α detection was examined with an enzyme-linked immunosorbent assay (ELISA) conducted with cell supernatants after cell stimulation for 6, 12, and 24 h. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey’s post hoc test (α=0.05). Results KaloreTM and FiltekTM Silorane were cytotoxic with or without light curing (p<0.05) after 24 h of incubation. KaloreTM stimulated the early production of TNF-α in comparison with control (p<0.05), whereas FiltekTM Silorane did not affect TNF-α levels after 6 and 12 h (p>0.05). However, after 24 h FiltekTM Silorane inhibited the production of TNF-α (p<0.05). Conclusions KaloreTM and FiltekTM Silorane were cytotoxic regardless of light curing. The extract obtained from KaloreTM after 15 days of incubation stimulated the production of TNF-α, unlike that obtained from FiltekTM Silorane.

Microbial contamination and disinfection methods of pacifiers

Objectives To evaluate the microbial contamination of pacifiers by Mutans Streptococci(MS) and the efficacy of different methods for their disinfection.Methods Twenty-eight children were assigned to a 4-stage changeover system with a 1-week interval. In each stage, children received a new pacifier and the parents were instructed to maintain their normal habits for 1 week. After this time, the pacifiers were subjected to the following 4 disinfection methods: spraying with 0.12% chlorhexidine solution, Brushtox® or sterile tap water, and immersion in boiling tap water for 15 minutes. Microbiological culture for MS and Scanning Electron Microscopy (SEM) were performed. The results were analyzed statistically by Friedman’s non-parametric test (a=0.05).Results The 0.12% chlorhexidine spray was statistically similar to the boiling water (p>0.05) and more effective than the Brushtox®spray and control (p<0.05). The analysis of SEM showed the formation of a cariogenic biofilm in all groups with positive culture.Conclusions Pacifiers become contaminated by MS after their use by children and should be disinfected routinely. Spraying with a 0.12% chlorhexidine solution and immersion in boiling water promoted better disinfection of the pacifiers compared with a commercial antiseptic toothbrush cleanser (Brushtox®).

Physicochemical Properties and Interfacial Adaptation of Root Canal Sealers

This study compared the physicochemical properties and interfacial adaptation to canal walls of Endo-CPM-Sealer, Sealapex and Activ GP with the well-established AH Plus sealer. The following analyses were performed: radiopacity, pH variation and solubility using samples of each material and scanning electron microscopy of root-filled bovine incisors to evaluate the interfacial adaptation. Data were analyzed by the parametric and no-parametric tests (α=0.05). All materials were in accordance with the ANSI/ADA requirements for radiopacity. Endo-CPM-Sealer presented the lowest radiopacity values and AH Plus was the most radiopaque sealer (p=0.0001). Except for ActiV GP, which was acidic, all other sealers had basic chemical nature and released hydroxyl ions. Regarding solubility, all materials met the ANSI/ADA recommendations, with no statistically significant difference between the sealers (p=0.0834). AH Plus presented the best adaptation to canal walls in the middle (p=0.0023) and apical (p=0.0012) thirds, while the sealers Activ GP and Endo-CPM-Sealer had poor adaptation to the canal walls. All sealers, except for ActiV GP, were alkaline and all of them fulfilled the ANSI/ADA requirements for radiopacity and solubility. Regarding the interfacial adaptation, AH Plus was superior to the others considering the adaptation to the bovine root canal walls.

Este estudo comparou as propriedades físico-químicas e a adaptação interfacial às paredes do canal dos cimentos Endo-CPM-Sealer, Sealapex e Activ GP com o bem estabelecido cimento AH Plus. As seguintes análises foram realizadas: radiopacidade, variação de pH e de solubilidade utilizando amostras de cada material, e microscopia eletrônica de varredura utilizando incisivos bovinos obturados para avaliar a adaptação interfacial. Os dados foram analisados utilizando testes paramétricos e não-paramétricos (α=0,05). Todos os materiais estavam de acordo com os requerimentos da ANSI/ADA para radiopacidade, sendo que o Endo-CPM-Sealer apresentou os menores valores de radiopacidade e o AH Plus foi o cimento mais radiopaco (p=0,0001). Exceto o Activ GP, que foi ácido, todos os outros cimentos apresentaram natureza química básica e liberaram íons hidroxila. Com relação à solubilidade, todos os materiais estavam de acordo com as recomendações da ANSI /ADA, sem diferença significante entre os cimentos (p=0,0834). O AH Plus apresentou a melhor adaptação às paredes do canal nos terços médio (p=0,0023) e apical (p=0,0012), enquanto que os cimentos Activ GP e Endo-CPM-Sealer apresentaram uma pobre adaptação às paredes do canal. Em conclusão, todos os cimentos, exceto o Activ GP, foram alcalinos e todos preencheram os requerimentos da ANSI/ADA para radiopacidade e solubilidade. Com relação à adaptação interfacial, o AH Plus foi superior aos demais para adaptação às paredes do canal radicular de incisivos bovinos.

FiltekTM Silorane and FiltekTM Supreme XT resins: tissue reaction after subcutaneous implantation in isogenic mice

The aim of this study was to evaluate the tissue compatibility of a silorane-based resin system (FiltekTM Silorane) and a methacrylate-based nanoparticle resin (FiltekTM Supreme XT) after implantation in the subcutaneous connective tissue of isogenic mice. One hundred and thirty five male isogenic BALB/c mice were randomly assigned to 12 experimental and 3 control groups, according to the implanted material and the experimental period of 7, 21 and 63 days. At the end of each period, the animals were killed and the tubes with the surrounding tissues were removed and processed for microscopic analysis. Samples were subjected to a descriptive and a semi-quantitative analyses using a 4-point scoring system (0-3) to evaluate the collagen fiber formation and inflammatory infiltrate. Data were statistically analyzed using the Kruskal Wallis test (?=0.05). The results showed that there was no significant difference between the experimental and control groups considering the three evaluation periods (p>0.05). The silorane-based and the methacrylate-based nanoparticle resins presented similar tissue response to that of the empty tube (control group) after subcutaneous implantation in isogenic mice.

O objetivo do presente estudo foi avaliar a compatibilidade tecidual de um sistema resinoso à base de silorane (FiltekTM Silorane) e de uma resina nanoparticulada à base de metacrilato (FiltekTM Supreme XT), após implantação no tecido conjuntivo subcutâneo de camundongos isogênicos. Um total de 135 camundongos isogênicos BALB/c machos foram randomicamente divididos em 12 grupos experimentais e em 3 grupos controles, de acordo com o material implantado e com o período experimental (7, 21 e 63 dias). Ao final de cada período, os animais foram mortos, sendo os tubos removidos com o tecido circundante e processados para análise microscópica. As lâminas foram submetidas a análise descritiva e análise semi-quantitativa empregando um sistema de escores de 4 pontos (0-3), a fim de avaliar a formação de fibras colágenas e o infiltrado inflamatório. Os dados obtidos foram submetidos à análise estatística por meio do teste de Kruskal Wallis (?=0,05). Os resultados mostraram que não houve diferença estatisticamente significante entre os grupos experimentais e controles, considerando os três períodos de avaliação (p>0,05). As resinas à base de silorane e à base de metacrilato apresentaram resposta tecidual semelhante à do tubo vazio (controle), após implantação no tecido conjuntivo de camundongos isogênicos.