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Endodontic Sealers (endodontic + sealer)
Selected AbstractsFracture strength of bovine incisors after intra-radicular treatment with MTA in an experimental immature tooth modelINTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2007E. A. Bortoluzzi Abstract Aim, To evaluate, using an experimental immature tooth model, the fracture resistance of bovine incisors submitted to different reinforcement treatments with mineral trioxide aggregate (MTA). Methodology, An immature tooth model was created by sectioning the coronal and apical portions of 40 bovine incisors 8 mm above and 12 mm below the cementoenamel junction. The root canals were irrigated with 1.0% sodium hypochlorite. They were enlarged both coronally and apically using number 703 carbide burs (ISO: 500,104-168-007-021) and their internal diameter was standardized to 2.1 mm. The specimens were assigned to four groups (n = 10): GI-control (without filling); GII-apical MTA plug + filling with gutta-percha and endodontic sealer; GIII-filling with MTA; GIV-apical MTA plug + filling with MTA + metallic post (Reforpost I). A polyether impression material was used to simulate the periodontal ligament. The specimens were submitted to a compressive load at a crosshead speed of 0.5 mm min,1 in a servo-hydraulic universal testing machine (MTS 810) applied at 45° to the long axis of the tooth until failure. Data were submitted to statistical analysis by the Kruskal,Wallis test at 5% significance level. Results, GIV presented the highest fracture resistance (32.7N) and differed significantly from the other groups (P < 0.05). No statistically difference was found between GII (16.6N) and GIII (23.4N) (P > 0.05). GIII had a significantly higher fracture resistance than GI (P < 0.05). Conclusions, The use of MTA + metallic post as an intra-radicular reinforcement treatment increased the resistance to fracture of weakened bovine teeth in an experimental immature tooth model. [source] Cytotoxicity and sealing properties of four classes of endodontic sealers evaluated by succinic dehydrogenase activity and confocal laser scanning microscopyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2004Serge Bouillaguet The objectives of this study were to evaluate the cytotoxicity and sealing properties of four classes of endodontic sealers (PCS/Kerr, RoekoSeal/Roeko, TopSeal/Dentsply, and EndoREZ/Ultradent). For cytotoxicity testing (MTT method), the materials were either placed immediately in contact with cultured cells or 24 h after setting, then evaluated at three subsequent time points (24 h, 48 h, or 1 wk). For the leakage study, extracted human roots were obturated with acrylic cones and sealers and immersed for 48 h into rhodamine-labeled lipopolysaccharide. The roots were then observed under a confocal laser scanning microscope to estimate (semiquantitatively) the presence of the rhodamine-lipopolysaccharide (LPS) inside the canal. The results showed that cytotoxicity generally increased with time, and that most materials pose significant cytotoxic risks, particularly in the freshly mixed condition. Further, all materials showed significant leakage although there was large variation among teeth. Overall, the silicon-based material (Roeko Seal) was less cytotoxic and more effective in sealing root canals against LPS leakage than other materials. [source] Prostaglandin E2 production and viability of cells cultured in contact with freshly mixed endodontic materialsINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2006K. K. Melegari Abstract Aim, To determine whether commonly used endodontic sealers could either induce or increase the release of prostaglandin E2 (PGE2) when in contact with cell types found in the periapical tissues. Methodology, Freshly mixed samples of Roth 801 sealer, Sealapex® and ProRoot® mineral trioxide aggregate (MTA) were placed in contact with cultured macrophages and fibroblasts for 24 h. The supernatant from the cultures was assayed for PGE2 using enzyme-linked immunosorbent assay. Cell viability counts were made. As a positive control, similar cultures were also exposed to lipopolysaccharide and the supernatant analysed for PGE2. Data were compared by anova. Results, The three materials examined in these experiments did not stimulate increased PGE2 release from either of the cell lines. In control cultures, lipolysaccharide increased PGE2 release from macrophages but not from fibroblasts. Viability counts revealed that, whilst Roth 801 sealer caused some cell death in both fibroblasts and macrophages, Sealapex® led to cell death only in the macrophage cultures. ProRoot® MTA did not lead to statistically significant cell death in either culture. Conclusions, Under 24-h culture conditions, the three freshly mixed test materials did not increase directly either production or release of PGE2 from either macrophages or gingival fibroblasts. Roth 801 decreased cell viability counts for both fibroblasts and macrophages. Sealapex® decreases macrophage viability. ProRoot® MTA did not affect viability in either cell line. [source] Presence of pores and vacuoles in set endodontic sealersINTERNATIONAL ENDODONTIC JOURNAL, Issue 10 2005L. Mutal Abstract Aim, To assess qualitatively the presence of pores and vacuoles in the structure of various endodontic sealers when set. Methodology, Eight specimens were prepared in keeping with Instituto Argentino de Racionalización de Materiales (IRAM) and ISO regulations for each of the 10 sealers assessed. Four specimens per sealer were examined to identify the presence of structural defects, termed pores, on the external surface. The remaining four specimens were used to examine the presence of defects on the surface exposed by cross-sectional fracture; these were termed vacuoles. The largest and smallest diameters of the pores and vacuoles were measured by scanning electron microscope on both surfaces. The structural defects were classified according to their frequency as abundant, frequent, scarce or exceptional. Results, Pores and vacuoles were consistently found in every specimen of each sealer. However, their frequency and dimensions were greater in zinc-eugenol-based sealers than in epoxy-resins and glass,ionomer sealers; they increased if the sealer contained calcium hydroxide. The diameter of the pores ranged from 5 to 320 ,m and the diameter of the vacuoles ranged from 80 to 500 ,m. The diameter of the vacuoles always exceeded that of the pores. Conclusions, Pores and vacuoles were a consistent finding in set sealers. Their frequency and size depended on the density of the sealer and increased when the sealers contained calcium hydroxide. [source] Rheological properties and biocompatibility of endodontic sealersINTERNATIONAL ENDODONTIC JOURNAL, Issue 8 2003A. E. Kaplan No abstract is available for this article. [source] Dissolution of root canal sealer cements in volatile solventsINTERNATIONAL ENDODONTIC JOURNAL, Issue 1 2000J. M. Whitworth Whitworth JM, Boursin EM. Dissolution of root canal sealer cements in volatile solvents. International Endodontic Journal, 33, 19,24, 2000. Aim There are few published data on the solubility profiles of endodontic sealers in solvents commonly employed in root canal retreatment. This study tested the hypothesis that root canal sealer cements are insoluble in the volatile solvents chloroform and halothane. Methodology Standardized samples (n=5) of glass ionomer (Ketac Endo), zinc oxide-eugenol (Tubli-Seal EWT), calcium hydroxide (Apexit) and epoxy resin (AH Plus) based sealers were immersed in chloroform or halothane for 30 s, 1 min, 5 min and 10 min. Mean loss of weight was plotted against time of exposure, and differences in behaviour assessed by multiple paired t-tests (P <0.01). Results Clear differences were shown in the solubility profiles of major classes of root canal sealer cements in two common volatile solvents. In comparison with other classes of material, Ketac Endo was the least soluble in chloroform and halothane (P <0.01), with less than 1% weight loss after 10 min exposure to either solvent. Apexit had low solubility with 11.6% and 14.19% weight loss after 10 min exposure to chloroform and halothane, respectively. The difference between solvents was not significant (P >0.01). Tubli-Seal EWT was significantly less soluble in halothane than chloroform (5.19% and 62.5% weight loss after 10 min exposure, respectively (P <0.01)). Its solubility in halothane was not significantly different from that of Apexit. AH Plus was significantly more soluble than all other materials in both chloroform and halothane (96% and 68% weight loss after 10 min exposure, respectively (P <0.01)). Conclusions There are significant differences in the solubility profiles of major classes of root canal sealer in common organic solvents. Efforts should continue to find a more universally effective solvent for use in root canal retreatment. [source] Evaluation of penetration and adaptation of three different sealers: a SEM studyJOURNAL OF ORAL REHABILITATION, Issue 9 2003S. Sevimay Summary, In this study, dentinal penetration and adaptation of three endodontic sealers were evaluated by using scanning electron microscope (SEM). Seventeen recently extracted, human maxillary anterior teeth were used. After the crowns were removed from the cementoenamel junction, the root canals were instrumented. The teeth were then randomly divided into three groups of five roots each and two teeth were used as controls. The smear layer was removed with EDTA and NaOCl. The canals were obturated with AH 26, CRCS, RSA sealers and gutta-percha using lateral condensation technique. Each root was sectioned longitudinally and then prepared for SEM evaluation. The SEM results showed that AH 26 was the best sealer penetrating into dentinal tubules and adapted to dentinal walls when compared with the CRCS and RSA. The CRCS and RSA occluded the orificies of dentinal tubules. The RSA showed that the penetration was less than AH 26 and more than CRCS. [source] | ||||||||||