Experimental Medications for Using in Endodontics: Cytotoxicity, Genotoxicity and Mutagenesis Analysis / Medicamentos Experimentais para Uso em Endodontia: Análise de Citotoxicidade, Genotoxicidade E Mutagênese

The objective was to evaluate the cytotoxic, genotoxic and mutagenic properties of two experimental medication in Endodontics. For cytotoxic evaluation, fibroblast and osteoblast cells (1x104 cells/well) were plated and divided into groups conforming to the product added in culture medium: EM1 - 20 µL of experimental medication 1 (EM1); EM2 - 20 µL of experimental medication 2 (EM2); VE - 20 µL of vehicle used in medications; C - without product. The MTT assay was performed at 24, 48 e 72 hours for cytotoxic analysis. For genotoxic and mutagenic evaluation, 42 male rats were used. After 1 and 7 days of tubes containing EM1 or EM2, or empty (NC) were subcutaneously implanted, and after 1 day, a single dose of cyclophosphamide (CY) to be applied, the bone marrow was collected and submitted to comet and micronuclei assay. The significance level of 5% was considered for all statistical analysis. The viability of fibroblasts was <70% to both medications at 24h, and EM1 at 72h; at 72h, the proliferation cells was observed in EM2 (>100%). Both medications were non-cytotoxic to osteoblasts, and the EM2 stimulate the cell proliferation at 72h. The damage frequency of CY was statistically similar to EM1 and different to EM2 (p<0.05). The number of micronuclei was insignificant to EM1 and EM2 and no difference to group NC (p>0.05). Despite the absence of mutagenesis and non-cytotoxicity to osteoblasts, the EM1 was cytotoxic and genotoxic to fibroblasts. The EM2 was non-genotoxic, non-cytotoxic and nonmutagenic. (AU)

O objetivo foi avaliar as propriedades citotóxicas, genotóxicas e mutagênicas de dois medicamentos experimentais em Endodontia. Para avaliação citotóxica, células fibroblásticas e osteoblásticas (1x104 células/poço) foram plaqueadas e divididas em grupos de acordo com o produto adicionado no meio de cultura: EM1 - 20 µL da medicação experimental 1 (EM1); EM2 - 20 µL da medicação experimental 2 (EM2); VE - 20 µL de veículo utilizado em medicamentos; C ­ sem produto. O ensaio MTT foi realizado aos 24, 48 e 72 horas para análise citotóxica. Para avaliação genotóxica e mutagênica foram utilizados 42 ratos machos. Após 1 e 7 dias foram implantados por via subcutânea tubos contendo EM1 ou EM2, ou vazios (NC), e após 1 dia, foi aplicada dose única de ciclofosfamida (CY), a medula óssea foi coletada e submetida ao ensaio de cometa e micronúcleos. O nível de significância de 5% foi considerado para todas as análises estatísticas. A viabilidade dos fibroblastos foi <70% para ambas as medicações às 24h e ao EM1 às 72h; às 72h, a proliferação de células foi observada em EM2 (>100%). Ambas as medicações foram não citotóxicas para os osteoblastos, e o EM2 estimulou a proliferação celular às 72h. A frequência de dano do CY foi estatisticamente semelhante ao EM1 e diferente do EM2 (p<0,05). O número de micronúcleos foi insignificante para EM1 e EM2 e não houve diferença para o grupo NC (p>0,05). Apesar da ausência de mutagênese e não citotoxicidade para osteoblastos, o EM1 foi citotóxico e genotóxico para fibroblastos. O EM2 era não genotóxico, não citotóxico e não mutagênico. (AU)

Cytotoxicity and genotoxicity of Bio-C Repair, Endosequence BC Root Repair, MTA Angelus and MTA Repair HP.

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.

Cytotoxicity and genotoxicity of Bio-C Repair, Endosequence BC Root Repair, MTA Angelus and MTA Repair HP

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.

Survey based assessment of diagnosis through periapical radiograph and CBCT and treatment of root resorption with Brazilian and American dentists and endodontists.

BACKGROUND: This study assesses and compares the knowledge level of endodontists (ENDs) and general dental practitioners (GPs) from Brazil and United States of America (USA) in the diagnosis and treatment of internal and external inflammatory root resorptions through periapical radiographic (PA) and cone beam computed tomography (CBCT) examinations. MATERIAL AND METHODS: A cross-sectional online questionnaire-based survey was presented to the volunteers containing questions regarding personal and professional profile, as well as three clinical cases of internal and external inflammatory root resorption. A series of multiple-choice questions about the diagnosis and treatment options were surveyed. The data collected was analysed by the Chi-square test with Yates correction with a significance level of 5 %. RESULTS: Most answers were considered adequate when all three questions about the diagnosis and all two questions relating to the treatment were answered accurately. A total of 374 dentists answered the survey (n: 229 from Brazil vs. 145 from USA) being 41% END and 59% GP. END presented higher level of knowledge than GP regarding to diagnosis and treatment of inflammatory root resorptions both in Brazil and USA (p<0.05); USA presented higher level of adequate responses than Brazil (p<0.05). CONCLUSIONS: END achieved a level of knowledge of the diagnosis and treatment of root resorption superior to the GP. Comparing the results obtained in both countries, it was observed that the USA had a higher correct response rate than Brazil. Key words:Internal root resorption, external root resorption, management, diagnosis, treatment.

Estudo in vitro da ação antimicrobiana de medicações intracanal experimentais sobre biofilmes de Enterococcus faecalis / In vitro study of the antimicrobial action of experimental intracanal medications on Enterococcus faecalis biofilm

Introdução: A eliminação do Enterococcus faecalis dos canais radiculares é fundamental para o sucesso do tratamento endodôntico, uma vez que esses microrganismos são de difícil eliminação, principalmente quando organizados em forma de biofilmes. A busca por drogas ou suas combinações que possam eliminar esses microrganismos é um dos principais objetivos terapêuticos. Objetivo: O presente estudo avaliou a ação antimicrobiana de medicações intracanal experimentais sobre biofilmes de Enterococcus faecalis. Métodos: Quarenta dentes bovinos unirradiculares foram utilizados; suas coroas foram seccionadas e as raízes foram instrumentadas e esterilizadas. As raízes foram contaminadas com suspensão contendo Enterococcus faecalis, mantidas em estufa a 37°C por 30 dias e divididas em quatro grupos, de acordo com a medicação intracanal: GI) medicação experimental 1 (clorexidina [CHX] 0,2%/metronidazol, doxiciclina); GII) medicação experimental 2 (CHX 0,2%/metronidazol, minociclina); GIII) clorexidina a 2% (CHX 2%); e GIV) solução salina. As raízes foram seladas e mantidas em estufa por 7 dias, em tubos contendo TSB. Dentina foi coletada e semeada por 24 h, para formação de UFCs. Os valores obtidos foram comparados pelos testes ANOVA e Tukey (p<0,05). Quando comparados os resultados, não houve diferenças entre os Grupos I, II e III; no entanto, eles foram significativamente diferentes do Grupo IV. Conclusão: As medicações intracanal experimentais exerceram ação antimicrobiana sobre biofilmes de Enterococcus faecalis (AU).

Background: The elimination of Enterococcus faecalis of the root canals is fundamental for endodontic success, since these microorganisms are difficult to killed, especially when organized in biofilms. The search for drugs or their combinations that can eliminate these microorganisms is one of the main therapeutic aim. This study evaluated the antimicrobial action of experimental intracanal medications on Enterococcus faecalis biofilms. Methods: Forty uniradicular bovine teeth were used; their crowns were removed, and the roots were instrumented and sterilized. The roots were contaminated with suspension containing Enterococcus faecalis and kept in an oven at 37°C for 30 days. The roots were divided into 4 groups according to the intracanal medication: I- experimental medication 1 (0.2% CHX/metronidazole/ doxycycline); II- experimental medication 2 (0.2% CHX/ metronidazole/minocycline), III- 2% chlorhexidine (2% CHX), and IV- saline solution. The roots were sealed and kept in tubes containing TSB in an oven for 7 days. Dentin was collected and seeded for 24 h for perform of CFUs. The values obtained were compared using ANOVA and Tukeys tests (p<0.05). When comparing the results, there were no differences among groups I, II and III; however, they were significantly different from group IV. Conclusion: The experimental intracanal medications exerted an antimicrobial action on Enterococcus faecalis biofilms (AU).

Antimicrobial action of NeoMTA Plus on mono- and dual-species biofilms of Enterococcus faecalis and Candida albicans: An in vitro study.

OBJECTIVE: To evaluate the antimicrobial action of NeoMTA Plus on mono- and dual-species biofilms of Enterococcus faecalis and Candida albicans. MATERIAL AND METHODS: A total of 171 sterile dentin blocks, measuring 4 mm × 4 mm × 1 mm, were incubated in media containing E. faecalis (3.1 × 108 cells/mL) and/or C. albicans (1 × 107 cells/mL) for 2 d. These blocks were randomly divided into three groups: the control (no treatment with biomaterials), MTA (treated with an MTA sample with width and thickness same as those of the dentin block after the material was set), and NeoMTA Plus (treated with NeoMTA Plus in a fashion similar to the treatment of the MTA group) groups. The biomaterials remained in contact with the biofilms for 24 h. Quantitative analyses of the number of colony-forming units (CFUs) and metabolic activity (XTT), were performed. Furthermore, qualitative analysis of biofilm structure was performed by scanning electron microscopy. Data were statistically analyzed considering a significance level of 5%. RESULTS: XTT and the number of CFUs were similar among the groups (p > 0.05). The type of biofilm (mono- or dual-species) or the biomaterial used (MTA or NeoMTA Plus) did not affect the results. Biofilm structure exhibited a robust architecture composed of yeast and bacterial cell multilayers and was homogeneous among the groups. CONCLUSION: NeoMTA Plus was not effective against mono- and dual-species biofilms of E. faecalis and C. albicans. Further research investigating biofilm removal methods including those involving the use of biomaterials with antiseptics and other supporting therapies is warranted.

Endodontic approach in a replanted tooth with an immature root apex and chronic apical periodontitis: a case report.

This study describes the clinical steps taken in the treatment of a patient who had an avulsed right upper central incisor that presented with incomplete root development and chronic apical periodontitis. A 7-year-old boy was referred from a private dentist to a dental office specializing in endodontics. The tooth had remained in a dry environment for 20 minutes, and tooth replantation was performed at an emergency appointment. After clinical and radiographic examinations, root canal decontamination was performed, followed by several changes in intracanal calcium hydroxide medication. Blood clot formation was attempted, but bleeding within the root canal was insufficient; therefore, we opted for an intracanal medication change to stimulate mineralized tissue formation in the apical region. Root obturation was performed 45 days after the last change of intracanal medication, and clinical, radiographic, and tomographic follow-up examinations were performed at 3, 6, 18, and 40 months after the endodontic intervention. The increase in thickness and length of the root structure and the absence of root resorption were verified through follow-up examinations. Therefore, it was concluded that the procedures used were successful for tooth replantation.

Influence of anti-allergic drugs used systemically on the process of root resorption during delayed tooth replantation: A study in rats.

BACKGROUND/AIM: Anti-allergic drugs can inhibit the hard tissue resorption process, and due to similarities between root resorption and bone mechanisms, it can be inferred that these drugs may also control root resorption. The aim of this study was to analyze the effects of anti-allergic drugs used systemically on the process of root resorption following delayed tooth replantation. MATERIALS AND METHODS: Thirty-two maxillary right incisors of rats were extracted and subsequently replanted. Rats were divided into four groups according to the anti-allergic drug administered: the rats in groups DEX, Q, and MO were treated systemically with dexamethasone phosphate, quercetin, and montelukast, respectively, and no systemic medication was administered to rats in group C. After 60 days, the animals were euthanized, and the specimens were processed for histomorphometric and immunohistochemical analyses. Statistical significance was set at P < .05. RESULTS: There were no significant differences between the groups in terms of inflammatory resorption, replacement resorption, or presence of tartrate-resistant acid phosphatase. In terms of events occurring in the periodontal ligament space, there was a difference between groups Q and MO due to the presence of dental ankylosis and inflammatory connective tissue (P < .05). A difference in inflammatory cells was also observed through CD45 immunolabeling between the DEX and Q groups when compared to the C group (P < .05). CONCLUSION: The systemic administration of anti-allergic drugs did not have an effect on the process of root resorption following delayed tooth replantation.

Reciprocating kinematics leads to lower incidences of postoperative pain than rotary kinematics after endodontic treatment: A systematic review and meta-analysis of randomized controlled trial.

BACKGROUND: Extrusion of infected debris into the periapical tissue has been cited as the major cause of postoperative pain, regardless of instrumentation technique. AIM: Comprehensively review two different kinematics of instrumentation (reciprocating and rotary) and association to the postoperative pain after endodontic treatment. METHODS: Two investigators performed a systematic review with meta-analysis. MEDLINE/PubMed, Cochrane Library, and Scopus supplied relevant data from studies published until February 2018 to answer the PICO question. Primary outcome was overall postoperative pain, and the secondary outcomes were nature of the pain (mild, moderate, and severe) at 12, 24, and 48 h. RESULTS: Ten randomized clinical trials fulfilled eligibility criteria, and five of them were submitted in the meta-analysis. Primary outcome indicated that reciprocating system results in less postoperative pain compared to rotary system (P < 0.05). As a secondary outcome, there was no statistical difference for mild, moderate, and severe pain after 12 and 24 h using reciprocating or rotary systems (P > 0.05). However, the reciprocation system showed less severe pain after 48 h (P < 0.05). CONCLUSION: Rotary motion had a negative impact on postoperative pain after endodontic treatment. Furthermore, after 48 h, more patients presented severe pain under rotary motion. More randomized clinical studies would be helpful.

Epidemiology of Maxillofacial Trauma in a Prehospital Service in Brazil.

Understanding facial trauma behaviors in different populations can help enhance effective prevention and efficient management of public resources in order to offer better treatment in large health systems. The aim of this study was to assess the epidemiology of maxillofacial trauma treated by a public health emergency care service. A cross-sectional study was conducted to assess maxillofacial trauma in patients treated by a public health service of emergency care at a midsize city in southern Brazil. Facial trauma records were retrieved directly from medical records from January 2010 to April 2014. The following variables were collected: patient age, sex, destination of patient after initial treatment, cause of trauma, and type of injury. Statistical analyses were performed using G tests with Williams' corrections (p < .05). The most frequent cause was road traffic collision (39.6%), followed by falls (33.6%) and interpersonal violence (22.0%). The prevalence of falls was higher in older adults. A statistically significant association was observed between age and causes (p < .05). After the initial care provided by the prehospital service, 44.1% of the patients were referred to secondary care centers and 40.1% to hospitals. Traffic accidents were the most common cause of facial trauma in Brazil, with a higher prevalence in young men. Falls were also a big concern for facial injuries, especially among older adults. Although most lesions could be classified as minor trauma, many patients are being treated at hospitals, which may increase the costs to the public health system.

Evaluation of Knowledge of Physical Education Students on Dental Trauma.

INTRODUCTION: Sports' practitioners are vulnerable to dental trauma; if this occurs, the emergency treatment should be fast and efficient. This may be performed by any person at the site of the accident, not only by dental professionals. Physical educators may face dental trauma and should be able to provide proper care. This study had the objective evaluated the knowledge of physical education graduates on dental trauma. MATERIALS AND METHODS: A questionnaire containing questions on dental trauma was applied to 199 physical education students; after collection of the questionnaires, data were tabulated and processed on the software Epi Info 2000 (Centers for Disease Control and Prevention, 1600 Clifton Rd., Atlanta, GA 30333, USA). As a result, only 36.7% of participants would take the individual suffering trauma to the dental professional, 56.8% believe that the avulsed tooth should be replanted, and 42.2% would replant it. Only 7.5% would store the avulsed tooth in an ideal storage medium for transportation. CONCLUSION: It was concluded that there is a lack of knowledge on dental trauma among physical education graduates, evidencing the need of public policies to allow education on this issue.

Cytotoxicity Evaluation of Root Canal Sealers Using an In Vitro Experimental Model with Roots.

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.

Cytotoxicity Evaluation of Root Canal Sealers Using an In Vitro Experimental Model with Roots

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.

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.

Evaluation of the genotoxicity and mutagenicity of Ca3SiO5-based cement.

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.

Evaluation of the genotoxicity and mutagenicity of Ca3SiO5-based cement

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.

Diffusion of hydroxyl ions from calcium hydroxide and Aloe vera pastes.

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.

Biocompatibility evaluation of biodentine in subcutaneous tissue of rats.

INTRODUCTION: Biodentine (Septodont, St-Maur-des-Fossés, France) is a new material suitable for various clinical situations in endodontics, such as perforation repair, retrograde filling, pulp capping, and others. Because it is a new material, its properties should be analyzed before routine clinical use. Thus, this study evaluated the biocompatibility of Biodentine in the subcutaneous tissue of rats. METHODS: This study was conducted on 15 male rats. Two incisions were made on the dorsal region of each animal for the introduction of 4 tubes. One tube was empty, 1 was filled with zinc oxide-eugenol cement, 1 was filled with mineral trioxide aggregate, and the last tube was filled with Biodentine. After 7, 14, and 30 days, the animals were sacrificed, and the specimens were submitted to histotechnical preparation. The histologic sections were stained with hematoxylin-eosin and analyzed using light microscopy. Scores were established according to the inflammatory process and were statistically compared using the Kruskal-Wallis test (P < .05). RESULTS: The analysis of the histologic sections evidenced a nonsignificant or mild presence of inflammatory reaction in the connective tissue in contact with the empty tube and the tube containing MTA, which was different from the tube containing zinc oxide eugenol. The connective tissue was moderately inflamed at 7 days when in contact with Biodentine; however, at 14 and 30 days, the inflammatory process was mild or nonsignificant. CONCLUSIONS: Biodentine was biocompatible with tissue after the 14th day.

Biocompatibility of a calcium hydroxide-propolis experimental paste in rat subcutaneous tissue.

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.

Diffusion of Hydroxyl Ions from Calcium Hydroxide and Aloe vera Pastes

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.

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.

Biocompatibility of a Calcium Hydroxide-Propolis Experimental Paste in Rat Subcutaneous Tissue

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.

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.