Tissue Response and Immunoexpression of Interleukin 6 Promoted by Tricalcium Silicate-based Repair Materials after Subcutaneous Implantation in Rats

Made available in DSpace on 2018-12-11T17:17:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-03-01Introduction: The aim of the present study was to evaluate the inflammatory response induced by experimental tricalcium silicate cement with 20% zirconium oxide (TSC) and MTA Plus (MTAP; Avalon Biomed Inc, Bradenton, FL) in rat subcutaneous tissues. Methods: Polyethylene tubes were filled with TSC (n = 20) and MTAP (n = 20) and implanted in the dorsal subcutaneous tissues of 32 rats. Empty tubes were used as the control (control group [CG], n = 20). After 7, 15, 30, and 60 days, the tubes with connective tissue were removed, and the inflammatory cells and immunolabeled cells for interleukin 6 (IL-6) were counted. Data were statistically analyzed using analysis of variance and the Tukey test (P ≤.05). Results: An increased number of inflammatory and immunolabeled cells for IL-6 were observed at 7 days. The number of inflammatory cells was higher for TSC and MTAP than the CG (P <.001) at 7 days; after 30 and 60 days, no significant differences were observed among the TSC, MTAP, and CG (P =.955). The number of immunolabeled cells for IL-6 was similar for TSC, MTAP, and CG at all evaluated periods. A gradual and significant decrease was observed in the number of inflammatory cells and IL-6–immunopositive cells. At 60 days, the capsules adjacent to TSC and MTAP exhibited fibroblasts and bundles of collagen fibers. Conclusions: TSC and MTAP caused a similar subcutaneous reaction in rats, suggesting that they are biocompatible and present similar immune responses.Department of Restorative Dentistry Araraquara Dental School UNESP–São Paulo State UniversityDepartment of Morphology Araraquara Dental School UNESP–São Paulo State University AraraquaraInstitute of Clinical Sciences College of Medical and Dental Sciences University of BirminghamDepartment of Restorative Dentistry Araraquara Dental School UNESP–São Paulo State UniversityDepartment of Morphology Araraquara Dental School UNESP–São Paulo State University Araraquar

The impact of the addition of iodoform on the physicochemical properties of an epoxy-based endodontic sealer

Due to the low radiopacity of Sealer 26, iodoform is frequently empirically added to this sealer. Thus, the interference of this procedure with the physicochemical properties of Sealer 26 must be evaluated. OBJECTIVE: This study evaluated the influence of the addition of iodoform on setting time, flow, solubility, pH, and calcium release of an epoxy-based sealer. MATERIAL AND METHODS: The control group was pure Sealer 26, and the experimental groups were Sealer 26 added with 1.1 g, 0.55 g or 0.275 g of iodoform. Setting time evaluation was performed in accordance with the ASTM C266-03 speciflcation. The analysis of flow and solubility was in accordance with the ISO 6876-2001 speciflcation. For the evaluation of pH and calcium ion release, polyethylene tubes were filled with the materials and immersed in flasks with 10 ml of deionized water. After 24 h, 7, 14, 21, 28, and 45 days pH was measured. In 45 days, the calcium released was evaluated with an atomic absorption spectrophotometer. RESULTS: The addition of iodoform increased setting time in comparison with pure sealer (P<0.05). As for flow, solubility, and calcium release, the mixtures presented results similar to pure sealer (p>0.05). In the 24 h period, the mixture with 1.1 g and 0.55 g of iodoform showed lower pH than pure sealer and than sealer added with 0.275 g of iodoform (P<0.05). CONCLUSIONS: The iodoform added to Sealer 26 interferes with its setting time and solubility properties. Further studies are needed to address the clinical signiflcance of this interference

Sealability of MTA and calcium hydroxidecontaining sealers

OBJECTIVES: The aim of this study was to evaluate the apical sealability of Fillapex(®), Endo-CPM-Sealer(®) and Sealapex(®). MATERIAL AND METHODS: Ninety-four freshly extracted single-rooted teeth were selected and decoronated. All teeth were radiographed to confirm the existence of a single and straight root canal, which was prepared using Protaper Universal and 2.5% sodium hypochlorite. The teeth were randomly divided in groups of 10 specimens each according to the sealer, and the canals were filled using the single cone technique and one of the sealers. Four additional teeth were used as controls. The teeth were submitted to dye leakage with Rhodamine B for 24 h but using vacuum on the initial 15 min. Thereafter, they were cut longitudinally and the leakage was measured in a linear fashion from apex to crown. Data were analyzed by ANOVA and Tukey's tests at 5% significance level. RESULTS: Fillapex(®) and Sealapex(®) showed significantly less dye leakage than Endo-CPM-Sealer(®) (p<0.05). CONCLUSIONS: It was concluded that Fillapex(®) and Sealapex(®) were able to prevent apical dye leakage differently from Endo-CPM-Sealer(®)

Radiopacity evaluation of Portland and MTA-based cements by digital radiographic system

OBJECTIVE: The aim of the present study was to evaluate the radiopacity of Portland and MTA-based cements using the Digora TM digital radiographic system. MATERIAL AND METHODS: The performed tests followed specification number 57 from the American National Standard Institute/American Dental Association (2000) for endodontic sealing materials. The materials were placed in 5 acrylic plates, especially designed for this experiment, along with a graduated aluminum stepwedge varying from 1 to 10 mm in thickness. The set was radiographed at a 30 cm focus-object distance and with 0.2 s exposure time. After the radiographs were taken, the optical laser readings of radiographs were performed by Digora TM system. Five radiographic density readings were performed for each studied material and for each step of the aluminum scale. RESULTS: White ProRoot MTA (155.99±8.04), gray ProRoot MTA (155.96±16.30) and MTA BIO (143.13±16.94) presented higher radiopacity values (p<0.05), while white non-structural Portland (119.76±22.34), gray Portland (109.71±4.90) and white structural Portland (99.59±12.88) presented lower radiopacity values (p<0.05). CONCLUSIONS: It was concluded that MTA-based cements were the only materials presenting radiopacity within the ANSI/ADA specifications