Association of Toll-like receptors 2, 3, and 4 genes polymorphisms with periapical pathosis risk.

BACKGROUND: The aim of this study was to investigate the role of gene variations of Toll-like receptors (TLR) 2, 3, and 4 on genetic susceptibility to periapical pathosis. MATERIAL AND METHODS: One hundred patients were included in the study and divided into two groups as follows; Control Group (n=50) that have root canal treatment and no periapical lesion, Patient Group (n=50) that have root canal treatment and periapical lesion. TLR2 Arg753Gln, TLR3 (c.1377C/T) and TLR4 Asp299Gly and Thr399Ile polymorphisms were genotyped by using PCR-RFLP. Genotypical analysis of control and patient groups were investigated to disclose whether there is any association between periapical lesions and gene variations. RESULTS: There are no significant statistical differences between control and patient groups according to TLR 2 and 4 gene sequence. On the contrary, CC allele detected 74% for TLR 3 in patient group, and this difference was found to be statistically significant (p < 0.005). CONCLUSIONS: According to these results, it can be suggested that patients with Toll-like receptor 3 gene polymorphisms could be susceptible to periapical pathosis.

Evaluation of the permeability of five desensitizing agents using computerized fluid filtration.

OBJECTIVE: The aim of this study was to evaluate the permeability of five desensitizing agents using computerized fluid filtration (CFF) test method. MATERIALS AND METHODS: Sixty dentin discs of 500 ± 200-mm-thick were prepared from middle dentin of bovine incisors without exposed the pulp and then randomly divided into five groups (n = 12). The permeability of the discs was measured using the CFF test method before and after application of the following desensitizers: Admira Protect (Voco, Cuxhaven, Germany), Seal and Protect (Dentsply, Konstanz, Germany), Sensi Kill (DFL, Brazil), Systemp Desensitizer (Ivoclar Vivadent, Liechtenstein), BisBlock (Bisco, USA). Fluid movement measurements were made at 2-min intervals for 8 min, and a mean of the values obtained was calculated for each specimen. The results were analyzed using Kruskal-Wallis test and Wilcoxon signed ranks tests with a significance threshold of P < 0.05. RESULTS: There were no significant differences in permeability among desensitizing agents (P > 0.05); however dentin permeability was reduced in all groups (P < 0.05). CONCLUSION: The in vitro fluid conductance of dentin discs were reduced by treating with these five desensitizing agents.

Push-out bond strengths: the Epiphany-Resilon endodontic obturation system compared with different pairings of Epiphany, Resilon, AH Plus and gutta-percha.

AIM: To assess the bond strength of the new resin-based Epiphany-Resilon root canal filling system, and to compare this with bond strengths of different pairings of AH Plus, gutta-percha, Epiphany and Resilon. METHODOLOGY: A total of 65 extracted human single-rooted teeth were used. All teeth were instrumented using a set of ProTaper rotary instruments. Irrigation was performed with 15 mL of 1.25% NaOCl between each instrument and the smear layer was removed during and after instrumentation with 5 mL of 17% EDTA. The canal spaces were filled with different combinations of core and sealer using lateral condensation, as follows: group 1, AH Plus + gutta-percha; group 2, AH Plus + Resilon; group 3, Epiphany + Resilon; group 4, Epiphany + gutta-percha; group 5 (control), gutta-percha only. Cylinders of root dentine 1.13 (0.06)-mm long were prepared from the coronal sections of the 65 teeth. The test specimens were subjected to the push-out test method. After adhesion testing, the remaining sections were examined under a stereomicroscope at x 25 magnification to determine the nature of bond failure. The values of bond strength were analyzed by one-way analysis of variance (ANOVA) and the post hoc Tukey's test, with significance set at P < 0.05. RESULTS: The respective mean push-out test values for groups 1-5 were: 2.000 +/- 0.369, 1.380 +/- 0.154, 1.706 +/- 0.340, 2.857 +/- 0.523 and 0.078 +/- 0.027 MPa. Significant difference (P < 0.001) occurred between the groups. Multiple paired comparisons (Tukey's test) revealed that group 4 (Epiphany + gutta-percha) had significantly (P < 0.001) greater bonding strength than all the other groups; group 1 (AH Plus + gutta-percha) had significantly (P < 0.05) greater bonding strength than group 2 (AH Plus + Resilon); and group 5 (control) had significantly (P < 0.05) lower bonding strength than all the other groups. Inspection of the surfaces revealed the bond failure to be mainly adhesive to dentine for all groups. CONCLUSIONS: The Epiphany-Resilon combination (group 3) was not superior to that of the AH Plus-gutta percha combination (group 1).