ABSTRACT
Background: Root canal obturation is an important step in endodontic treatment, which is performed aiming to three-dimensionally seal the canal and prevent microleakage, reentry, and proliferation of microorganisms in the root canal system. On the other hand, microleakage eventually leads to root canal treatment failure. Sealing ability is an important property of endodontic sealers. This in vitro study aimed to compare the quality of apical seals obtained by three endodontic sealers. Materials and Methods: This in vitro experimental study evaluated 48 extracted single-canal maxillary incisors. Hard- and soft-tissue residues were removed and the teeth were immersed in 5.25% of sodium hypochlorite for disinfection. The teeth were decoronated at the cementoenamel junction with a diamond disc such that 10 mm of root length remained. Canal patency was ensured using a #10 K-file. The canals were then instrumented with ProTaper rotary system. The canals were randomly divided into three experimental groups for the application of Adseal, Proseal, and AH26 sealers, and positive and negative control groups. Sealers were applied in the canals using lateral compaction technique. The external root surfaces were then coated with two layers of nail varnish except for the apical 3 mm. The amount of microleakage was quantified using the dye-penetration technique. The Tukey's test was used to compare the microleakage between the experimental and control groups. The Kruskal-Wallis test was applied to compare the microleakage of experimental groups (P < 0.05). Results: The amount of microleakage in canals filled with Adseal, Proseal, and AH26 sealers with lateral compaction technique was 2.33 ± 0.64, 2.2 ± 0.81, and 2.22 ± 0.71 µm, respectively. No significant difference was noted among the three sealers regarding microleakage (P = 0.84). However, the amount of microleakage in the sealer groups was significantly lower than that in the control group (P < 0.001). Conclusion: The application of Adseal, Proseal, and AH26 had equal efficacy for the provision of optimal apical seal in filling of root canals with lateral compaction technique. The application of sealers yielded a significantly superior apical seal compared with the control group.
ABSTRACT
Due to the widespread use of MTA in dentistry and various brands of this product, we decided to compare the three brands available in the country market by their biocompatibility. We divided 20 male Wistar rats into four groups. After local anesthesia and washing, we made two incisions on both sides (4 incisions in total). The experimental groups were Angelus MTA (Angelus, Brazil), BioMTA (CERKAMED, Poland), Root MTA (Dr. Lotfi, Tabriz, Iran), and the control group. The resulting paste was placed in a tube and implanted subcutaneously into male Wistar rats. Wistar rats were sacrificed 7, 15, 30, and 60 days later, with high anesthetic doses. The sample implanted in 10% formalin was stabilized after tissue processing and H&E staining under a microscope. The inflammatory reaction in the tissues received different scores at the beginning of the tube opening. BioMTA had the highest inflammatory response among the groups, but the difference was not statistically significant (p > 0.05). Also, there was no significant difference between the groups' granulation and calcification (p < 0.05). There was a significant difference between BioMTA, Angelus MTA, Root MTA, and control groups in fibrous capsule formation (p < 0.05). Angelus MTA showed the lowest mean fibrous capsule formation in all periods. The effects of Angelus MTA, Root MTA, and BioMTA on connective tissue were investigated and compared. According to this study, these materials have good biocompatibility. According to the findings and statistical analysis, Angelus MTA has the most biocompatibility.
ABSTRACT
INTRODUCTION: Apical transportation changes the physical shape and physiologic environment of the root canal terminus. The aim of the present experimental study was to determine the extent of apical transportation after instrumentation with hand K-Flexofile and K3 rotary instruments by means of cone-beam computed tomography (CBCT). METHODS AND MATERIALS: Forty mesiobuccal root canals of maxillary first molars, with 19-22 mm length and 20-40(°) canal curvature, were selected and assigned into two preparation groups. The first group was prepared with K-Flexofile with passive step-back technique and the second group was prepared with K3 rotary instruments. Pre and post instrumentation CBCT images were taken under similar conditions. The amount of root canal transportation was evaluated by Mann-Whitney U test and the chi-square test was used for the qualitative evaluation. RESULTS: The amounts of apical canal transportation with the K3 and K-Flexofile instruments were 0.105±0.088 and 0.150±0.127 mm, respectively with no statistically significant differences. In the manual technique, 25% of the canals had no apical transportation; while 30% of the canals in the K3 group were transportation free. CONCLUSION: Both systems were able to preserve the initial curvature of the canals and both had sufficient accuracy. Preparation with K3 rotary instruments resulted in apical transportation similar to that of K-Flexofile.
