Recently, various calcium silicate-based sealers have been introduced for use in root canal filling. The MTA Fillapex is one of these sealers, but some of its physicochemical properties are not in accordance with the ISO requirements. Objective: The aim of this study was to evaluate the flowability, pH level and calcium release of pure MTA Fillapex (MTAF) or containing 5% (MTAF5) or 10% (MTAF10) calcium hydroxide (CH), in weight, in comparison with AH Plus sealer. Material and Methods: The flowability test was performed according to the ISO 6876:2001 requirements. For the pH level and calcium ion release analyses, the sealers were placed individually (n=10) in plastic tubes and immersed in deionized water. After 24 hours, 7 and 14 days, the water in which each specimen had been immersed was evaluated to determine the pH level changes and calcium released. Flowability, pH level and calcium release data were analyzed statistically by the ANOVA test (α=5%). Results: In relation to flowability: MTAF>AH Plus>MTAF5>MTAF10. In relation to the pH level, for 24 h: MTAF5=MTAF10=MTAF>AH Plus; for 7 and 14 days: MTAF5=MTAF10>MTAF>AH Plus. For the calcium release, for all periods: MTAF>MTAF5=MTAF10>AH Plus. Conclusions: The addition of 5% CH to the MTA Fillapex (in weight) is an alternative to reduce the high flowability presented by the sealer, without interfering in its alkalization potential.

The aim of the present study was to evaluate the effect of calcium hydroxide dressing on the bond strength of three commercially available endodontic sealers (MTA Fillapex, Sealapex, and AH Plus) to root canal dentin. Sixty slices of extracted human canines were obtained from cervical, middle, and apical root thirds. Root canals were standardized and specimens were filled and divided into six groups (n = 10): G1, MTA Fillapex; G2, Sealapex; and G3, AH Plus, with prior application of calcium hydroxide dressing; and G4, G5 and G6, without prior application of intracanal dressing. After 7 days, specimens were submitted to a push-out test. The data obtained were analyzed using the ANOVA and Tukey tests (a = 5%). Fracture modes were classified as adhesive, cohesive or mixed. The results of sealer bond strength to root canal dentin varied according to the sealer, root third and prior dressing application. Overall, calcium hydroxide dressing reduced bond strength in all root thirds, but the reduction was significant only for AH Plus, at the cervical (3.25 ± 1.69) and apical (4.43 ± 1.65) thirds (p < 0.05). AH Plus showed the highest bond strength for all root thirds (p < 0.05) compared to the other groups. G1, G2, G4 and G5 showed similar bond strength values for all root thirds (p > 0.05). In conclusion, the calcium hydroxide dressing only had a negative effect on the bond strength of AH Plus, at the cervical and apical thirds. On the other hand, the bond strength values for MTA Fillapex and Sealapex were lower than those for AH Plus and, whereas the mixed failure mode predominated for AH Plus, the adhesive failure mode predominated for MTA Fillapex and Sealapex.

OBJETIVO: O objetivo do estudo foi avaliar a efetividade da guta-percha e Resilon no preenchimento de canais laterais nos terços cervical, médio e apical radicular quando utilizada a técnica termomecânica. MATERIAL E MÉTODO: Canais radiculares de dentes artificiais foram preparados utilizando um método padrão. Canais laterais foram confeccionados utilizando broca com 0,3 mm de diâmetro nos três terços radiculares. Os canais radiculares foram obturados pela técnica híbrida de Tagger utilizando-se o compactador de McSpadden. Foi avaliado o preenchimento dos canais laterais pelos seguintes materiais: cones de guta-percha Dentsply, guta-percha Endopoint e Resilon. A avaliação foi realizada por meio da análise de radiografias digitalizadas usando o programa Image Tool. A porcentagem da área preenchida pela área total de cada canal lateral foi determinada. Os dados foram submetidos à análise de variância (ANOVA) e teste de Tukey com nível de significância de 5%. RESULTADO: O Resilon mostrou melhor efetividade como material de preenchimento. Na comparação entre os terços, o Resilon foi mais efetivo no terço apical que no cervical (p < 0,05). CONCLUSÃO: O Resilon foi o material mais efetivo para o preenchimento dos canais laterais quando utilizada a técnica termoplástica.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of gutta-percha and Resilon in filling lateral root canals in cervical, middle, and apical third using a thermomechanical technique. MATERIAL AND METHOD: Root canals of artificial teeth were prepared using a standard preparation. The lateral canals were fabricated using a 0.3-mm-diameter bur at 3 parts of each root. By using Tagger's hybrid technique with a McSpadden thermomechanical compactor, the root canal was filled using the following filling materials: Dentsply gutta-percha, Endopoint gutta-percha, and Resilon cones. The root canal fillings were evaluated using digitized radiographs and the Image Tool software. The percentage of filled area of each lateral canal was determined. The data were subjected to analysis of variance (ANOVA) and Tukey tests at a 5% significance level. RESULT: Resilon showed better effectiveness as a filling material. When the three thirds were compared, Resilon was more effective in the apical third than in the cervical third (p < 0.05). CONCLUSION: Resilon is an effective filling material for lateral root canals using a thermomechanical technique.

Foi propósito deste trabalho observar o processo de reparo de dentes de cães após obturação dos canais com dois cimentos diferentes, fazendo ou não a patência apical. Após uma sobreinstrumentação, os canais receberam um curativo de uma solução de corticosteróide-antibiótico por 7 dias, com o objetivo de obter invaginação de tecido conjuntivo para dentro dos canais. Após esse período, esse tecido foi totalmente removido em metade dos casos (grupos com patência apical) e preservados no restante dos casos (grupos sem patência apical). Os canais foram obturados pela técnica da condensação lateral empregando um cimento a base de hidróxido de cálcio (Sealer Plus) ou um cimento de Grossman (Fill Canal). Os animais foram sacrificados por overdose anestésica 60 dias após o tratamento endodôntico e as peças anatômicas foram obtidas e preparadas para análise histológica. Os dados obtidos foram analisados com base em diversos parâmetros histomorfológicos. Os resultados foram melhores nos grupos sem patência apical (p=0,01) do que nos grupos com patência. Dentre os cimentos estudados, os melhores resultados foram observados com o cimento Sealer Plus (p=0,01). Em conclusão, tanto a patência apical (presença ou ausência) quanto o tipo de material obturador de canal influíram no processo de reparo apical de dentes de cães com polpas vitais após tratamento endodôntico. O emprego de um cimento a base de hidróxido de cálcio em dentes sem patência apical promoveu os melhores resultados, dentre as condições experimentais propostas.

The purpose of this study was to investigate the periapical healing process of dogs' teeth with or without apical patency and after root canal filling with two types of sealers. Forty roots of premolars and incisors were utilized. The root canals were overinstrumented and dressed with a corticosteroid-antibiotic solution for 7 days to obtain ingrowth of periapical connective tissue into the canals. After this period, the tissue was removed in half of the specimens (groups with patency) and preserved in the other half (groups without patency). Canals were filled by lateral condensation technique with gutta-percha points and either a calcium hydroxide-based sealer (Sealer Plus) or a Grossman's cement (Fill Canal). The animals were killed by anesthetic overdose 60 days after the endodontic treatment and anatomic pieces were obtained and prepared for histologic examination. Data were evaluated in a blind analysis on the basis of several histomorphologic parameters. The groups without patency had better results (p=0.01) than those in which the ingrown connective tissue was removed. Comparing the sealers, Sealer Plus had significantly better results (p=0.01) than Fill Canal. In conclusion, both the apical patency (presence or absence) and the type of root canal filling material influenced the periapical healing process in dogs' teeth with vital pulp after root canal treatment. The use of a calcium hydroxide-based sealer in teeth without apical patency yielded the best results among the experimental conditions proposed.