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Made available in DSpace on 2015-08-06T16:14:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-24. Added 1 bitstream(s) on 2015-08-06T16:44:25Z : No. of bitstreams: 1 S1806-83242014000100204.pdf: 317262 bytes, checksum: e4dcb4d3e8d4a7d0f7b84170b5fa5780 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) 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. Univ. Estadual Paulista Araraquara Dental School Department of Restorative Dentistry Universidade de São Paulo Bauru Dental School Department of Dentistry, Endodontics and Dental Materials

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:58:56Z No. of bitstreams: 1 S0103-64402005000100002.pdf: 590917 bytes, checksum: 6d64c3be46b629a5bfffd10330feb682 (MD5) Made available in DSpace on 2013-08-22T18:58:56Z (GMT). No. of bitstreams: 1 S0103-64402005000100002.pdf: 590917 bytes, checksum: 6d64c3be46b629a5bfffd10330feb682 (MD5) Previous issue date: 2005-04-01 Made available in DSpace on 2013-09-30T19:55:10Z (GMT). No. of bitstreams: 2 S0103-64402005000100002.pdf: 590917 bytes, checksum: 6d64c3be46b629a5bfffd10330feb682 (MD5) S0103-64402005000100002.pdf.txt: 27938 bytes, checksum: eeaab533c833a643bb0d334915730646 (MD5) Previous issue date: 2005-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:44:27Z No. of bitstreams: 2 S0103-64402005000100002.pdf: 590917 bytes, checksum: 6d64c3be46b629a5bfffd10330feb682 (MD5) S0103-64402005000100002.pdf.txt: 27938 bytes, checksum: eeaab533c833a643bb0d334915730646 (MD5) Made available in DSpace on 2014-05-20T13:44:27Z (GMT). No. of bitstreams: 2 S0103-64402005000100002.pdf: 590917 bytes, checksum: 6d64c3be46b629a5bfffd10330feb682 (MD5) S0103-64402005000100002.pdf.txt: 27938 bytes, checksum: eeaab533c833a643bb0d334915730646 (MD5) Previous issue date: 2005-04-01 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. UNESP Faculty of Dentistry of Araçatuba Department of Restorative Dentistry UNIMAR Faculty of Dentistry UNIP Faculty of Dentistry UNESP Faculty of Dentistry Department of Pediatric and Social Dentistry UNESP Faculty of Dentistry of Araçatuba Department of Restorative Dentistry UNESP Faculty of Dentistry Department of Pediatric and Social Dentistry

The aim of this study was to evaluate the effects of large apical preparations in the danger zones of the mesial root canals of mandibular molars instrumented with the Mtwo and Reciproc systems (VDW, Munich, Germany) until reaching apical diameters of 0.25 and 0.40 mm.Twelve mandibular molars, the mesial roots of which presented distinct foramens and similar anatomies, were selected using micro-computed tomographic scanning. Mtwo and Reciproc instruments were used to shape the mesiobuccal or mesiolingual canals. The mesial canals were scanned before and after the use of 0.25- and 0.40-mm Mtwo and Reciproc instruments. The analyzed parameters included the root canal volume and remaining dentin thickness at 5 different levels. The obtained data were subjected to paired analysis of variance and Tukey or Friedman and Dunn tests for intragroup analysis and the Mann-Whitney U test for comparison between the mesial and distal walls.There were no significant differences between the mesial and distal dentin thickness for the points analyzed with both instrumentation techniques (P.05). The volumetric analysis revealed a significant difference (P.05) among the initial volume and after the use of the 0.25- and 0.40-mm instruments for both systems. The use of the 0.40-mm instrument increased the root canal volume in comparison to the 0.25-mm instrument (P.05).Both systems performed similarly for the preparation of curved root canals with separate apical foramens. The increase of the root canal preparation with the 0.40-mm instrument significantly increased the root canal volume at the apical third without significantly reducing the dentin thickness in the danger zone for both instrument systems.