جستجوی مقالات مرتبط با کلیدواژه « Sealing » در نشریات گروه « پزشکی »

Statement of the Problem: The most common cause of endodontic treatment failures is improper coronal sealing. Therefore, besides to proper root sealing, coronal sealing which is supported by a proper restoration has a major role in endodontic treatment success, and coronal microleakage should be considered as an etiologic factor in endodontic treatment failure. Glass-ionomer (GI) has been proposed as a coronal barrier for microleakage after endodontic treatment. This study aimed to evaluate the coronal microleakage in GI-obturated root canals in endodontically treated teeth using different thicknesses of GI. In this invitro study, forty-five single-rooted extracted human teeth with single canals were collected and disinfected with 0.5% chloramine solution. After endodontic treatment, teeth were divided into 3 groups. In the group 1 to 3, 1 to 3 mm of gutta-percha was removed and GI was replaced at 1-, 2- and 3-mm thicknesses respectively. Then subgroups were placed in methylene blue dye and the microleakage was assessed using dye penetration. The mean dye penetration in groups 1, 2 and 3 were 5.1, 3.7 and 2.9, respectively, with statistically significant differences. Group 1 exhibited the highest amount of dye penetration while group 3 showed the least one. Moreover, a significant difference between groups 1 and 2 (p= 0.002) and a non-significant difference between groups 2 and 3 (p= 0.098) was detected in mean dye penetration.   Thicker layers of GI might decrease the coronal microleakage. GI at 3-mm thickness resulted in the best protective effect on coronal microleakage in endodontically treated teeth, though further studies are needed to confirm these results.

Sealing ability is one of the most important features of endodontic sealers. The main goal of the present study was to compare sealing ability of mineral trioxide aggregate (MTA)‑propylene glycol (PG) with two commonly used resin‑based and MTA‑based sealers. In This in vitro study Seventy extracted single‑root teeth were used. Canal preparation was carried out using hand and RaCe rotary files. Ten teeth were used as control. The root canals in positive and negative control groups were left empty. Remaining 60 teeth were randomly divided into following four groups (n = 15): In Group 1, the canals were dried using paper cones and obturated using MTA‑PG sealer. In Group 2, saline was removed from canal using a syring, but paper cones were not used. Obturation was done using MTA‑PG sealer. In Groups 3 and 4, the canals were dried using paper cones and obturated with AH26 and MTA Fillapex, respectively. Two‑chamber method was used to evaluate bacterial leakage using Enterococcus faecalis (ATCC 29212). Turbidity of the lower chambers was checked every day during 90 days. Chi‑square, Kaplan–Meier analysis, and logrank tests were used to compare groups regarding leaked samples at the end of the study. The level of significance was set at 0.05. There was no significant difference among groups regarding rate of leakage throughout the study. However, at the end of the study, the groups were statistically different regarding leaked samples (P = 0.034). MTA Fillapex and MTA‑PG in dry canal showed the most and least leaked samples at the end of the study, respectively (P < 0.05). MTA mixed with PG has superior sealing ability than MTA Fillapex.

The purpose of this paper was to review the composition, sealing ability, biocompatibility and various physical properties of cold ceramic (CC) material that potentially used as a root filling material. Thereview of the articles was performed by electronic and manual searching methods regarding theproperties of CC from November 2000 to May 2016. The results revealed that there were many published reports carried out on the properties of CC. Only one article had extensively studiedthe composition of CC, five studies had investigated the sealing ability of CC, three articles hadstudied the biocompatibility, and some studies had investigated the radiopacity, setting time, pH value, and solubility of CC. It was concluded that CC material had good potential for endodonticuse. Furthermore, clinical studies are needed in these areas.

Introduction
The materials used in sealing furcating perforation can have considerable effects on controlling the ensuing inflammation and periodontal repair. The objective of the present study was to carry out a histological comparison between the effects of pro-root, cold ceramic, glass-ionomer cement, and root MTA on the healing of periodontal tissues after furcal perforation in dog''s teeth.
Methods and Materials
One-hundred premolar teeth of one-year old dogs were used in this experimental/animal study. After anesthetizing the dogs and the premolar teeth, the access cavities were prepared at the occlusal level and the root canals were instrumented and filled with gutta percha and AH26 sealer, using the step-back technique. Furcations were perforated to a size of 3×3 mm2, using long burs. These areas were then randomly filled with aforementioned four test materials (a total number of 84 premolar teeth) while the access cavities were filled with amalgam. The remaining 16 teeth were selected to serve as positive and negative controls. Biopsy samples were taken from the perforated areas at 1, 2, and 3-month intervals and were transferred to laboratory for pathological examination. The results were statistically analyzed, using the Kruskal-Wallis and Mann Whitney tests.
Results
The statistical analysis revealed that under similar conditions, periodontal tissues surrounding Pro-root, show less inflammatory response than the other three materials. However, no significant differences were observed among the four studied materials during 1 and 2months as evidenced by the biopsy samples (P>0.05). For longer period (three month), however, samples surrounding cold ceramic and Root MTA showed decreasing inflammatory responses.

Discussion
From the findings of the present study, it may be concluded that although tissues adjacent to Pro-root showed less inflammatory response than other three test materials, all of them (Pro-root, Glass-ionomer cement, cold ceramic, and Root MTA) may be considered to be suitable materials for sealing furcal perforation providing. They receive approval by other tests including micro leakage, cytotoxicity, tissue analysis, and etc.