Abstract The aim was to evaluate in vitro cytotoxicity and genotoxicity of Bio-C Repair (BCR), compared to Endosequence BC Root Repair (ERRM), MTA Angelus (MTA-Ang), and MTA Repair HP (MTA-HP). MC3T3 osteoblastic cells were exposed to extracts of the repairing bioceramic cements. After 1, 3, and 7 days, cytotoxicity and genotoxicity were evaluated by MTT and Micronucleus tests, respectively. Cells not exposed to biomaterials were used as a negative control. Data were compared using ANOVA two-way, followed by the Tukey Test (α=5%). MTA-Ang and MTA-HP showed no difference in relation to control regarding cytotoxicity in any experimental times. BCR and ERRM reduced cell viability after 3 and 7 days (p<0.05); however, the reduction caused by BCR was less than that caused by ERRM. Considering the micronucleus formation, all biomaterials caused an increase after 3 and 7 days (p<0.05), being greater for the BCR and ERRM groups. It can be concluded that BCR is non-cytotoxic in osteoblastic cells, as well as MTA-Ang e MTA Repair HP. BCR and ERRM showed greater genotoxicity than others tested biomaterials.

Resumo O objetivo foi avaliar in vitro a citotoxicidade e genotoxicidade do Bio-C Repair (BCR), em comparação com o Endosequence BC Root Repair (ERRM), MTA Angelus (MTA-Ang) e MTA Repair HP (MTA-HP). As células osteoblásticas MC3T3 foram expostas aos extratos dos cimentos biocerâmicos reparadores. Após 1, 3 e 7 dias, a citotoxicidade e a genotoxicidade foram avaliadas pelos testes MTT e Micronúcleo, respectivamente. Células não expostas aos biomateriais foram utilizadas como controle negativo. Os dados foram comparados por ANOVA de dois fatores, seguido do Teste de Tukey (p = 5 %). MTA-Ang e MTA-HP não apresentaram diferença em relação ao controle quanto à citotoxicidade em nenhum dos tempos experimentais. BCR e ERRM reduziram a viabilidade celular após 3 e 7 dias (p < 0,05); no entanto, a redução causada pelo BCR foi menor que aquela causada pelo ERRM. Todos os biomateriais causaram aumento na formação de micronúcleos após 3 e 7 dias (p < 0,05), sendo maior para os grupos BCR e ERRM. O BCR não é citotóxico em células osteoblásticas, assim como cimentos MTA-Ang e MTA Repair HP. BCR e ERRM apresentaram maior genotoxicidade do que outros biomateriais testados.

Resumo O objetivo do presente estudo foi avaliar a citotoxicidade dos cimentos dos canais radiculares em condições próximas à realidade clinica. Uma linhagem primária de fibrolastos humanos foi semeada em placas acrílicas de 24-poços com meio de cultura Dulbecco’s modified Eagle’s medium suplementado com 10% de soro fetal bovino e incubados por 24 h. Os canais radiculares de pré-molares foram obturados e individualmente adaptados aos dispositivos de nylon para serem estabilizados nos poços com as células já semeadas. Amostras foram dividas de acordo com os grupos: Controle: cones de gutta-percha (CGP); AH Plus+CGP; Sealapex+CGP; MTA Fillapex+CGP e Endofill+CGP. Após 24 e 48 h, a viabilidade e a morfologia celular foram avaliadas pelo ensaio de MTT e microscopia eletrônica de varredura (MEV), respectivamente. Análises estatísticas foram realizadas pelo teste de Mann-Whitney, complementadas por Kruskal Wallis (p<0,05). Apenas o Endofill apresentou citotoxicidade após 24 h. MTA Fillapex e Endofill reduziram a produção da enzima desidrogenase succinica após 48 h. AH Plus não apresentou toxicidade em nenhum momento. MEV mostrou que os grupos AH Plus e o MTA Fillapex apresentaram fibroblastos com morfologia próxima ao grupo controle, enquanto que o grupo do Endofill apresentou poucas células com finos prolongamentos. O presente estudo demonstrou que resultados satisfatórios foram apresentados nos grupos AH Plus e Sealapex, mas não para o Endofill após 48 h. O método utilizado permitiu avaliar a citotoxicidade dos cimentos que se difundem pelo ápice radicular.

Abstract The aim of the present study was to evaluate the cytotoxicity of root canal sealers under conditions closely resembling a clinical reality. A primary human fibroblast cell line was seeded in 24-well acrylic plates with Dulbecco’s modified Eagle’s medium supplemented with 10% serum fetal bovine (SFB) and incubated for 24 h. Root canals from premolars were filled and individually attached to nylon devices to be stabilized in the wells with the already seeded cells. Specimens were divided into groups as follows: Control: gutta-percha cones (GPC); AH Plus+GPC; Sealapex+GPC; MTA Fillapex+GPC and Endofill+GPC. After 24 and 48 h, cell viability and morphology were evaluated by MTT assay and scanning electron microscopy (SEM), respectively. Statistical analysis was performed by Mann-Whitney test, complemented by Kruskal Wallis test (p<0.05). Only Endofill presented cytotoxicity after 24 h. MTA Fillapex and Endofill reduced the production of succinic desidrogenase after 48 h. AH Plus was non-toxic at any time point. SEM showed that the AH Plus and MTA Fillapex groups presented fibroblasts with morphology close to the control group, while the Endofill group presented few cells with thin extensions cells. The present study showed that good results were present in AH Plus and Sealapex, but not the Endofill group after 48 h. The method used enabled evaluation of the cytotoxicity of the studied sealers that diffused through the root apex.

Abstract Ca3SiO5 is new cement based on the composition of Portland that has been developed to have superior physicochemical and biological properties. In a clinical evaluation, the cement did not appear to have cytotoxic properties and allowed for the proliferation of pulp cells and gingival fibroblasts. However, no previous studies have evaluated the genotoxicity or the mutagenicity of Ca3SiO5in vivo. Therefore, the goal of this study is to evaluate the genotoxic and mutagenic potential of Ca3SiO5-based cement in vivo. Twenty-four male Wistar rats were divided into 3 groups (n = 8). Group A rats received subcutaneous implantation of Ca3SiO5 in the dorsum. Group B rats received a single dose of cyclophosphamide (positive control). Group C rats received subcutaneous implantation of empty tubes in the dorsum (negative control). After 24 hours, all animals were euthanized and the bone marrow of the femurs was collected for use in the comet assay and the micronucleus test. The comet assay revealed that the Ca3SiO5 group had a tail intensity of 23.57 ± 7.70%, the cyclophosphamide group had a tail intensity of 27.43 ± 7.40%, and the negative control group had a tail intensity of 24.75 ± 5.55%. The average number of micronuclei was 6.25 (standard deviation, SD = 3.53) in the Ca3SiO5 group, 9.75 (SD = 2.49) in the cyclophosphamide group, and 0.75 (SD = 1.03) in the negative control group. There was an increase in the micronuclei frequency in the Ca3SiO5 group compared to that of the negative control group (p < 0.05). Our data showed that exposure to the Ca3SiO5-based cement resulted in an increase in the frequency of micronuclei, but no genotoxicity was detected according to the comet assay.

Este estudo avaliou a difusão de íons hidroxila de diferentes pastas de hidróxido de cálcio contendo Aloe vera através dos túbulos dentinários. Foram utilizados 60 dentes bovinos unirradiculares. As coroas dos dentes foram removidas, os canais radiculares foram instrumentados e divididos em 4 grupos (n=15) de acordo com a medicação intracanal: Grupo HC/SF - pasta de hidróxido de cálcio e soro fisiológico; Grupo HC/P - pasta de hidróxido de cálcio e propilenoglicol; Grupo HC/A - pasta de hidróxido de cálcio e Aloe vera gel; Grupo HC/A/P - pasta de hidróxido de cálcio, propilenoglicol e Aloe vera. Após o preenchimento dos canais radiculares com as respectivas pastas, os dentes foram selados coronalmente e na região do ápice radicular com adesivo epóxi. Os dentes foram colocados em frascos identificados contendo água deionizada e armazenados em estufa, com 100% de umidade, a 37°C. Após 3h, 24h, 72h, 7 dias, 15 dias e 30 dias, a água deionizada dos frascos foi coletada e realizada a medição do pH com auxílio de um pHmetro. Os dados obtidos foram submetidos à análise estatística, com grau de significância de 5%. Os resultados mostraram que todas as pastas estudadas promoveram a difusão dos íons hidroxila através dos túbulos dentinários. A associação do Aloe vera ao HC (grupo HC/A) resultou em uma liberação de forma constante de íons cálcio. O grupo HC/A/P mostrou o pH mais elevado que as demais pastas em 24 e 72 horas. Concluiu-se que as pastas experimentais contendo Aloe vera foram capazes de permitir a difusão de íons hidroxila através dos túbulos dentinários.

This study evaluated the diffusion through the dentinal tubules of hydroxyl ions from different calcium hydroxide (CH) pastes containing Aloe vera. Sixty single-rooted bovine teeth were used. The tooth crowns were removed, the root canals were instrumented and the specimens were assigned to 4 groups (n=15) according to the intracanal medication: Group CH/S - CH powder and saline paste; Group CH/P - CH powder and propylene glycol paste; Group CH/A - calcium hydroxide powder and Aloe vera gel paste; Group CH/A/P - CH powder, Aloe vera powder and propylene glycol paste. After placement of the root canal dressings, the teeth were sealed coronally and apically with a two-step epoxy adhesive. The teeth were placed in identified flasks containing deionized water and stored in an oven with 100% humidity at 37 °C. After 3 h, 24 h, 72 h, 7 days, 15 days and 30 days, the deionized water in the flasks was collected and its pH was measured by a pH meter. The obtained data were subjected to statistical analysis at a significance level of 5%. The results demonstrated that all pastes provided diffusion of hydroxyl ions through the dentinal tubules. The combination of Aloe vera and CH (group CH/A) provided a constant release of calcium ions. Group CH/A/P showed the highest pH at 24 and 72 h. In conclusion, the experimental pastes containing Aloe vera were able to enable the diffusion of hydroxyl ions through the dentinal tubules.

Medicações intracanais são fundamentais para a desinfecção do sistema de canais radiculares e para a participação no reparo, a biocompatibilidade dos medicamentos deve ser considerada para não danificar os tecidos. Assim, esse estudo avaliou a biocompatibilidade de pasta experimental de hidróxido de cálcio associado à própolis em tecido subcutâneo de rato. Esse estudo foi conduzido em 15 ratos machos. Duas incisões foram feitas na região dorsal de cada animal para a introdução de 4 tubos. Um tubo estava vazio, um tubo tinha óxido de zinco e eugenol e os outros foram preenchidos com pasta experimental. Após 7, 14 e 30 dias, os animais foram mortos e os espécimes foram submetidos a preparação histotécnica. Os cortes histológicos foram analisados em microscópio de luz. Escores foram estabelecidos de acordo com o processo inflamatório e comparados estatisticamente por meio do teste de Tukey (p<0,05). A análise dos cortes histológicos evidenciou insignificante ou discreta presença de reação inflamatória em contato com o tubo vazio em todos os períodos estudados, enquanto que o tecido conjuntivo em contato com o óxido de zinco e eugenol mostrou inflamação moderada ou severa sem diferença ao longo dos períodos estudados. O tecido conjuntivo estava com inflamação moderada aos 7 dias quando em contato com a pasta; no entanto, aos 14 e 30 dias, o processo inflamatório foi discreto ou insignificante. A pasta experimental foi biocompatível com os tecidos após o 14° dia.

Intracanal medications are fundamental for disinfection of the root canal system and participate in periapical repair, so their biocompatibility is of utmost importance to avoid tissue damage. This study evaluated the biocompatibility of a experimental paste of calcium hydroxide and propolis in the subcutaneous tissue of rats. The study was conducted on 15 male Wistar rats. Two incisions were made on the dorsal region of each animal for introduction of 4 tubes: one tube was empty; one contained zinc oxide-eugenol cement, and the two other tubes were filled with experimental paste. After 7, 14 and 30 days, the animals were euthanized and the specimens were subjected to histotechnical preparation. The hematoxylin and eosin-stained histological sections were analyzed by light microscopy. Scores were established according to the inflammatory process and statistically compared by the Tukey test (α=5%). The analysis of histological sections showed non-significant or mild inflammatory reaction in the connective tissue in contact with the empty tubes in all study periods while the contact of subcutaneous tissue with zinc oxide-eugenol elicited moderate or severe inflammation similarly without significant difference among the study periods. The connective tissue was moderately inflamed at 7 days when contacting the experimental paste, but the inflammatory process was non-significant or mild at 14 and 30 days. The experimental paste was biocompatible with the tissues after 14 days of subcutaneous implantation.

This study evaluated the ability of ions from a non-alcoholic calcium hydroxide-propolis paste to diffuse through dentinal tubules. Thirty-six single-rooted bovine teeth were used. The tooth crowns were removed, and the root canals were instrumented and divided into 3 groups: Group 1 - calcium hydroxide-propylene glycol paste; Group 2 - calcium hydroxide-saline solution paste; Group 3 - calcium hydroxide-propolis paste. After the root canal dressings were applied, the teeth were sealed and placed in containers with deionized water. The pH of the water was measured after 3, 24, 72 and 168 hours to determine the diffusion of calcium hydroxide ions through the dentinal tubules. All of the pastes studied promoted the diffusion of calcium hydroxide ions through the dentinal tubules. Associating propolis to calcium hydroxide resulted in a pH increase, which occurred with greater intensity after 72 hours. The calcium hydroxide-propolis paste was able to diffuse in dentin.

Este trabalho teve como objetivo avaliar o uso do ácido zoledrônico, um inibidor da reabsorção, como medicação para o tratamento da reabsorção radicular em dentes reimplantados tardiamente. Para isso, 24 incisivos centrais superiores direito de ratos foram avulsionados e mantidos a seco por 30 min. A seguir, os dentes foram divididos em 2 grupos. No grupo I, a superfície radicular foi tratada com solução de fluoreto de sódio a 2% por 20 min; no grupo II, foi usada solução de ácido zoledrônico a 10-6M, por 20 min. Todos os canais foram instrumentados e preenchidos com pasta de hidróxido de cálcio. Posteriormente, os dentes foram reimplantados em seus respectivos alvéolos. Após 15 e 60 dias do reimplante, os animais foram mortos e as peças obtidas foram preparadas para análise microscópica e morfométrica. Os resultados demonstraram que o ácido zoledrônico foi capaz de limitar a ocorrência da reabsorção radicular e previniu a reabsorção do cemento. Futuras pesquisas devem ser realizadas para confirmar o uso do ácido zoledrônico para o tratamento da superfície radicular em reimplantes tardios.

This study evaluated the use of zoledronic acid, a resorption inhibitor, as a medication for root resorption treatment of late replanted teeth. Twenty-four maxillary right central incisors of rats were avulsed and kept dry for 30 min. Then, the teeth were divided into 2 groups. In group I, root surface was treated with 2% sodium fluoride for 20 min; in group II, 10-6M zoledronic acid solution was used for 20 min. All root canals were filled with calcium hydroxide. Next, teeth were replanted in their respective sockets. After 15 and 60 days post-replantation, the animals were killed and the anatomic pieces were obtained and prepared for microscopic and morphometric analyses. The results showed that zoledronic acid was capable of limiting the occurrence of root resorption and preserving cementum resorption. Further research must be performed to confirm the use of zoledronic acid in root surface treatment of late replanted teeth.

This study aimed to evaluate the diffusion capacity of calcium hydroxide pastes with different vehicles through dentinal tubules. The study was conducted on 60 extracted single-rooted human teeth whose crowns had been removed. The root canals were instrumented and divided into 4 groups according to the vehicle of the calcium hydroxide paste: Group I - distilled water; Group II - propylene glycol; Group III - 0.2% chlorhexidine; Group IV - 2% chlorhexidine. After placement of the root canal dressings, the teeth were sealed and placed in flasks containing deionized water. After 1, 2, 7, 15, 30, 45 and 60 days, the pH of the water was measured to determine the diffusion of calcium hydroxide through the dentinal tubules. The data were recorded and statistically compared by the Tukey test. The results showed that all pastes presented a similar diffusion capacity through dentin. Group IV did not present difference compared to group I. Group II presented difference compared to the other groups, as did Group III. In conclusion, groups I and IV presented a better diffusion capacity through dentin than groups II and III; 2% chlorhexidine can be used as a vehicle in calcium hydroxide pastes.

Este estudo investigou a biocompatibilidade de pastas experimentais a base de acetazolamida em tecido subcutâneo de rato. Duas pastas foram usadas neste estudo. Ambas continham a acetalozamida como componente principal em concentrações similares. O veículo usado na pasta experimental 1 foi o soro fisiológico e na pasta experimental 2 foi o propilenoglicol. Sessenta tubos de polietileno foram selados em uma das extremidades com guta-percha, que serviu como controle. Metade dos tubos foi preenchida com a pasta 1 e metade com a pasta 2. Os tubos foram introduzidos no tecido subcutâneo de 15 ratos (4 tubos por animal). Aos 7, 15 e 45 dias após a cirurgia, os animais foram sacrificados e os espécimes processados em laboratório. Os cortes histológicos foram corados com hematoxilina e eosina e analisados em microscópio de luz. Escores foram estabelecidos de acordo com a intensidade do processo inflamatório: 1-sem inflamação; 2-discreta; 3-moderada; 4-severa. Os dados obtidos foram comparados estatisticamente através do teste de Kruskal-Wallis (p≤0,05). A pasta 1 promoveu processo inflamatório aos 7 dias. Entretanto, sua intensidade diminuiu com o tempo e estava praticamente ausente aos 45 dias. Não foi observada diferença estatisticamente significante entre o controle (guta-percha) e a pasta 1. Entretanto, a pasta 2 promoveu reação inflamatória em todos os períodos experimentais, com diferença estatisticamente significante em relação ao controle. Assim, a pasta experimental de acetazolamida 1 foi considerada biocompatível como o controle deste trabalho. Já a pasta experimental 2 foi irritante aos tecidos.

This aim of this study was to investigate the biocompatibility of two experimental acetazolamide (AZ)-based pastes in the subcutaneous tissue of rats. Both pastes contained AZ as the main component in similar concentration. The vehicle in experimental paste 1 was saline, while experimental paste 2 was prepared with propylene glycol. Sixty polyethylene tubes were sealed at one end with gutta-percha (GP), which served as a control. Half of the tubes were filled with paste 1 and half with paste 2. The tubes were implanted in the subcutaneous tissue of 15 rats, being 4 tubes for each animal. The animals were killed 7, 15 and 45 days after surgery and the specimens were processed in laboratory. The histological sections were stained with hematoxylin and eosin and were analyzed by light microscopy. Scores were assigned to level of inflammatory process: 1- none; 2- mild; 3- moderate; 4- severe. The data were analyzed statistically by the Kruskal-Wallis test (p≤0.05). Paste 1 produced an inflammatory process at 7 days. However, the intensity of this inflammation decreased with time and was nearly absent at 45 days. No statistically significant difference (p>0.05) was observed between the control (GP) and paste 1. However, paste 2 produced inflammatory response at all study periods and differed significantly (p<0.05) from the control. In conclusion, in the present study, the experimental AZ-based paste 1 was considered as biocompatible as the control matrial (GP), while experimental paste 2 was irritating to rat subcutaneous tissue.

Tooth avulsion is a very common event in children and emergency care procedures are crucial for case prognosis. As anyone at the moment of accident can provide first-aid measures, knowledge of school professionals dealing with children is of paramount importance. An informative campaign about dental trauma was performed in urban schools in the city of Adamantina, São Paulo state, Brazil, in an attempt to educate school professionals about emergency procedures in cases of tooth avulsion. A questionnaire arguing on personal information, tooth avulsion knowledge and personal impressions of the campaign was handed out for evaluation of the informative campaign. Eighty school professionals participated in the survey. Most participants were females (93.75%) aged 41-60 years old (53.75%) with a college degree (77.5%). Time at work ranged from 1-5 years (22.5%). The efficacy of the campaign was considered positive, as 100% of the interviewees replied to the importance of emergency procedures in case of tooth avulsion. In addition, 81.25% of the respondents answered that they would store the avulsed tooth in some storage medium, of which milk was the most frequently mentioned (84.61%). The participants considered the campaign as satisfactory and a region-wide campaign will be accomplished at other schools.

Este trabalho teve como objetivo testar o efeito da solução de nitrato de gálio, uma substância anti-reabsortiva, quando usada no tratamento da superfície radicular de dentes reimplantados tardiamente, com o intuito de inibir o processo de reabsorção radicular e facilitar o reparo. Para isso, foram utilizados 20 incisivos centrais superiores direitos de ratos, divididos em 2 grupos (n=10). No grupo I, a superfície radicular foi tratada com solução de nitrato de gálio a 10-4M por 20 min e no grupo II com fluoreto de sódio a 2% por 20 min. Todos os canais foram preenchidos com pasta de hidróxido de cálcio. Após 15 e 60 dias do reimplante, os animais foram mortos e as peças obtidas, processadas em laboratório para análise em microscópio de transmissão de luz. Em ambos os grupos, houve pequena ocorrência de anquilose e reabsorção radicular. O tecido conjuntivo formado no espaço do ligamento periodontal disposto paralelamente à raiz, na maioria dos espécimes dos dois grupos, mostrou-se inflamado e com algumas áreas de necrose. No grupo I, houve a formação de bolsa periodontal em todos os espécimes aos 60 dias, indicando a ausência de reparo. Estes achados desaconselham o uso do nitrato de gálio para o tratamento de superfície de dentes reimplantados tardiamente.

The aim of this study was to investigate the effect of gallium nitrate solution, an anti-resorption substance, when applied for root surface treatment in rat teeth submitted to delayed replantation, in order to inhibit the root resorption process and enhance repair. For such purpose, 20 maxillary right central incisors of rats were randomly assigned to 2 groups (n=10). In group I, root surface was treated with 10-4M gallium nitrate solution for 20 min, while in group II root surface was treated with 2% sodium fluoride for 20 min. All root canals were filled with a calcium hydroxide-based paste. At 15 and 60 days after replantation, the animals were killed and the specimens were processed in laboratory for light transmission microscopy. In both groups, there was mild occurrence of ankylosis and root resorption. The connective tissue formed at the periodontal ligament area was arranged parallel to the root in most specimens in both groups and presented signs of inflammation. In group I, there was periodontal pocket formation in all specimens at 60 days, revealing lack of repair. These findings contraindicate the use of gallium nitrate for root surface treatment of teeth submitted to late replantation.

Este trabalho tem como objetivo testar a solução de nitrato de gálio, um inibidor da reabsorção, como curativo intracanal para dentes reimplantados tardiamente. Trinta incisivos centrais superiores direitos de ratos foram avulsionados e mantidos a seco por trinta minutos. Todos os dentes tiveram os canais radiculares instrumentados e a superfície radicular tratada com hipoclorito de sódio a 1%, seguido de fluoreto de sódio a 2%. Após isso, os dentes foram divididos em dois grupos de acordo com a medicação intracanal: no grupo I, foi usada solução de nitrato de gálio e grupo II, pasta de hidróxido de cálcio. Todos os dentes foram, então, reimplantados em seus respectivos alvéolos. Passados 15, 30 e 60 dias do reimplante, os animais foram sacrificados e as peças obtidas, processadas em laboratório para análise microscópica e morfométrica. Os resultados mostraram que a solução de nitrato de gálio e a pasta de hidróxido de cálcio limitaram a reabsorção radicular, mas não impediram a sua ocorrência. Conclui-se que ambos os medicamentos têm ação semelhante.

The purpose of this study was to test a gallium nitrate solution, a resorption inhibitor, employed as a root canal dressing in teeth submitted to late replantation. Thirty maxillary right central incisors of rats were avulsed and kept dry for thirty minutes. The teeth were instrumented and the root surfaces were treated with 1% hypochlorite solution followed by application of 2% sodium fluoride. Thereafter, the teeth were divided into two groups according to the root canal dressing: Group I, solution of gallium nitrate; and Group II, calcium hydroxide paste. The teeth were then replanted in their respective sockets. The animals were killed at 15, 30 and 60 days after replantation and the samples were processed for morphometric and microscopic analysis. The results demonstrated that the gallium nitrate solution and the calcium hydroxide paste limited the root resorption, yet they did not impair its occurrence. It may be concluded that gallium nitrate solution and calcium hydroxide paste demonstrated similar performance.

Objetivou-se avaliar a influência do curativo intracanal de hidróxido de cálcio sobre a capacidade dos corantes azul de metileno e rhodamine B de marcar a dentina, quando incorporados à massa obturadora, no momento da espatulação. Quarenta pré-molares inferiores humanos extraídos tiveram seus canais instrumentados sendo, então, divididos em quatro grupos. Em dois grupos, os canais foram preenchidos com pasta de hidróxido de cálcio e propilenoglicol por 15 dias. Os outros, permaneceram em água destilada. Após a remoção do curativo, todos os canais foram obturados com condensação lateral e cimento de óxido de zinco e eugenol acrescidos de azul de metileno ou rhodamine B. Assim, em dois grupos (com e sem curativo), os canais foram obturados com cimento contendo azul de metileno e os outros, rhodamine B. Decorridos 15 dias, as raízes foram seccionadas transversalmente nos terços cervical, médio e apical, procedendo-se à análise da marcação, com atribuição de escores às características da mesma. O teste de Mann-Whitney acusou marcação estatisticamente menor (p < 0,05) no grupo curativo/azul de metileno. Baseado nos resultados, concluiu-se que o curativo intracanal de hidróxido de cálcio interfere negativamente na capacidade marcadora do azul de metileno, diminuindo-a consideravelmente.

The objective of this study was to evaluate the influence of calcium hydroxide in intracanal dressing on the ability of the dyes rhodamine B and methylene blue to label the dentine. Forty extracted human mandibular premolars had their canals instrumented and were divided into four groups: in two groups, the canals were filled with a calcium hydroxide paste and the others remained in distilled water. After 15 days, in two groups (with and without dressing), the canals were obturated with sealer containing methylene blue, whereas the others contained rhodamine B. For analysis, the roots were transversally sectioned in their cervical, medium and apical thirds, and the labeling was analyzed. The Mann-Whitney test showed statistically significant difference between the dressing/methylene blue group and the others. Based on these results, it was concluded that calcium hydroxide in intracanal dressing negatively interferes with the labeling ability of methylene blue.

Os cimentos ionoméricos representam importante opção de material restaurador em Odontologia e sua adesão à estrutura dental, diminuindo a infiltração marginal, somada à liberação de flúor, inibindo o metabolismo de microrganismos acidogênicos e favorecendo a remineralização dental, podem diminuir a ocorrência de cárie secundária. A aplicação tópica de géis acidulados ou neutros contendo flúor tem sido largamente utilizada em Odontologia. No entanto, este procedimento pode afetar a integridade dos materiais restauradores, aumentando sua rugosidade e a retenção de placa bacteriana. Dessa forma, o presente estudo avaliou o período de tempo no qual o cimento ionomérico Vitremer mantém sua capacidade inibitória sobre Streptococcus mutans ATCC 25175 e a adesão dos mesmos sobre a superfície do material, bem como a influência da aplicação tópica de flúor acidulado e neutro sobre esses parâmetros microbiológicos e as características superficiais daquele material. Verificou-se que a atividade antimicrobiana do cimento ionomérico Vitremer se mantém por aproximadamente quatro dias e não é recuperada com o uso de flúor gel acidulado ou neutro. Observou-se, também, que Streptococcus mutans ATCC 25175 adere ao material restaurador testado sendo que a aplicação tópica de flúor não influenciou esta adesão. As características superficiais desses materiais não se alteraram com a aplicação dos géis.

Glass ionomer cements are important options in restorative and preventive dentistry due to their adhesion to the tooth surface and to fluoride release, which can decrease the risk of recurrent caries. The topical use of acidulated and neutral fluoride gels has been frequent in dentistry. However, this procedure can adversely affect the surface of restorative materials, increasing their roughness and the retention of dental plaque. Thus, this study evaluated the period in which Vitremer glass ionomer cement maintains its antimicrobial activity over Streptococcus mutans ATCC 25175, as well as the effects of topical application of acidulated and neutral fluoride gels on these microbiological parameters and on the superficial characteristics of the restorative material. It was verified that the antimicrobial activity of Vitremer is very transient, decreasing to an undetectable level after four days, and the topical application of fluoride gel did not restore this activity. It was observed that S. mutans ATCC 25175 adheres to this restorative material, and the topical fluorides did not affect this event. The surface of Vitremer was not altered by the application of fluoride gels.