Cytotoxicity of two resin-based sealers and a fluoride varnish on human gingival fibroblasts.

INTRODUCTION: Assessment of cellular cytotoxicity is a regular method for evaluating the biocompatibility of novel materials. In a recent study, 5% fluoride varnish (Duraflur) has shown reasonable sealing ability and coverage of root canal walls when used as a sealer. The aim of the present study was to compare the cytotoxicity of Duraflur varnish with two popular commonly used root canal sealers (AH-Plus and AH-26) on human gingival fibroblasts (HGF). METHODS AND MATERIALS: The HGFs were incubated with different concentrations (1/2, 1/4, and 1/8) of AH-plus, AH-26, and Duraflur varnish for 24 h. The percentage of cell viability was assessed with methyl-thiazol-tetrazolium (MTT) assay. The data was analyzed using the one-way ANOVA followed by Student-Newman-Keuls test. The level of significance was set at 0.001. RESULTS: MTT assay showed that higher concentrations of the tested materials resulted in lower viability of HGFs. AH-Plus showed significantly greater cell viability compared to AH-26 at all dilutions (P<0.001); however, no significant difference was found between Duraflur and AH-Plus in terms of cell viability at 1/8 dilution (P>0.001). Duraflur showed significantly higher cell viability compared to AH-26 except at 1/2 dilution (P<0.001). CONCLUSION: Although Duraflur varnish had better biocompatibility compared to AH-26, it should still be evaluated with further biocompatibility tests such as intraosseous and subcutaneous implantation.

The effect of premedication with ibuprofen and indomethacin on the success of inferior alveolar nerve block for teeth with irreversible pulpitis.

INTRODUCTION: Achieving pulp anesthesia with irreversible pulpitis is difficult. This study evaluated whether nonsteroidal anti-inflammatory drugs assist local anesthesia. METHODS: In a randomized double-blinded clinical trial, 150 patients (50 per group) with irreversible pulpitis were given placebo, 600 mg ibuprofen, or 75 mg indomethacin 1 hour before local anesthesia. Each patient recorded their pain score on a visual analog scale before taking the medication, 15 minutes after anesthesia in response to a cold test, during access cavity preparation and during root canal instrumentation. No or mild pain at any stage was considered a success. Data were analyzed by the chi-square and analysis of variance tests. RESULTS: Overall success rates for placebo, ibuprofen, and indomethacin were 32%, 78%, and 62%, respectively (p < 0.001). Ibuprofen and indomethacin were significantly better than placebo (p < 0.01). There was no difference between ibuprofen and indomethacin (p = 0.24). CONCLUSIONS: Premedication with ibuprofen and indomethacin significantly increased the success rates of inferior alveolar nerve block anesthesia for teeth with irreversible pulpitis.

Effect of phosphate buffer saline on coronal leakage of mineral trioxide aggregate.

This study was carried out to compare the bacterial leakage of MTA used as a root-end filling material when it was kept in phosphate buffer saline (PBS) or normal saline. In this study, 72 freshly extracted teeth were used. The roots were randomly divided into four experimental groups of 15 each (groups I and II gutta-percha obturation + MTA, groups III and IV only MTA) and two positive and negative control groups of six each. The samples in groups I and III were kept in normal saline for 1 month while the samples in groups II and IV were kept in PBS. Enterococcus faecalis was used for determination of the bacterial penetration. Kaplan-Meier survival curve and chi(2) test were employed for data analysis. The obturated samples with root-end filling showed significantly longer duration of resistance to bacterial penetration than canals without obturation (P < 0.05). The roots that were placed in PBS (groups II and IV) showed significantly less bacterial penetration in comparison with the roots that were stored in normal saline (P < 0.05). In conclusion, MTA, which acts as a bioactive material, should be placed in a synthetic tissue fluid before any leakage evaluation.