The Effect of Er:YAG Laser on Entroccocus faecalis Bacterium in the Pulpectomy of Anterior Primary Teeth

Introduction: Successful root canal therapy depends on the complete elimination of micro-organisms such as Entroccocus faecalis, which is impossible to achieve with the traditional methods. Lasers are recently introduced as a new method to solve the problem. The present study is planned and performed to examining the antibacterial effect of Er: YAG laser.Methods: Sixty extracted anterior primary teeth were prepared and sterilized. E. faecalis bacterium was cultured in canals. Samples were randomly divided into two groups. The first group was disinfected by NaOCl 5/25% and Er: YAG laser and the second group just by NaOCl 5/25%. Samples of canal contents were cultured and colony counts were calculated. The results were analyzed statistically by SPSS software and Mann Whitney test.Results: There was no significant difference between colony counts in both groups (P = 0.142). But the number of colonies in the first group was lower than in the second group.Conclusion: Although, Er: YAG laser cannot completely eliminate E. faecalis bacterium, its simultaneous use with NaOCl decreases E. faecalis

Knowledge and Attitudes of Elementary Schoolteachers on Dental Trauma and its Management in Yazd, Iran

Statement of the Problem: School is one of the places with the greatest prevalence of occurrence of traumatic dental injuries. Purpose: The aim of this study was to assess the knowledge levels and attitudes of elementary school teachers towards dental trauma and its management. Materials and Method: In this cross-sectional study, 281 elementary school teachers were selected through cluster sampling to answer the prepared questionnaire. The data obtained from the questionnaires were analyzed in SPSS software by using ANOVA test and t-test. p Value<0.05 was considered to be significant. Results: The total knowledge and attitude were low and normal, respectively. No previous exposure to or close observation of a dental trauma was reported by 61.2% of teachers; while, 12.5% were trained on dental traumas first aid management. There was statistically significant relationship between the teacher’s knowledge and previous first aids training. Conclusion: The knowledge of schoolteachers on emergency management of dental trauma is poor. Therefore, it seems to be helpful to consider the management of dental injuries especially avulsed teeth as a part of teachers' education

Thermal Changes of Root Surface of Anterior Primary Teeth in Pulpectomy with Er:YAG Laser

Objectives: Successful root treatment depends on elimination of microorganisms from the root canal. Considering incomplete removal of bacteria from the canal by usual methods, lasers have been suggested as a new modality. Despite their anti-bacterial properties, lasers can cause thermal changes. This study assessed the thermal changes of root surface in pulpectomy of primary teeth following the use of Er:YAG laser. Materials and Methods: Sixty primary anterior teeth were collected and prepared by K-file up to number 50. Then, they were randomly divided into two groups and were irradiated with Er:YAG laser. The first group was irradiated with 1 W laser and the second group with 1.5 W laser. The laser irradiation time was two 10-second cycles with a 2-second interval in both groups. Thermal changes were measured by a thermometer in the apical and coronal areas per second. The results were analyzed by repeated measures ANOVA considering the laser power as between-subject variable. Results: There was a temperature increase in the coronal and apical areas in use of 1 W power. There was a temperature rise in the coronal and apical areas in use of 1.5 W power. The temperature rise in the apical third was more than that in the coronal third; also, the average temperature rise was more in use of 1.5 W power than 1 W power. Conclusions: As the average temperature increase was not more than 7°C in any group, this type of laser seems to be suitable for root treatment of primary anterior teeth

Association of vitamin D receptor BsmI, TaqI, FokI, and ApaI polymorphisms with susceptibility of chronic periodontitis: A systematic review and meta-analysis based on 38 case–control studies

Background: There has been increasing interest in the study of the association between Vitamin D receptor (VDR) gene polymorphisms and risk of chronic periodontitis. However, the results remain inconclusive. To better understand the roles of VDR polymorphisms (BsmI, TaqI, FokI, and ApaI) in chronic periodontitis susceptibility, we conducted this systematic review and meta-analysis. Materials and Methods: The PubMed, Google Scholar, and Web of Science database were systemically searched to determine all the eligible studies about VDR polymorphisms and risk of chronic periodontitis up to April 2017. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the associations between VDR polymorphisms and chronic periodontitis risk. All the statistical analyses were performed by Comprehensive Meta-Analysis. All P values were two-tailed with a significant level at 0.05. Results: Finally, a total of 38 case–control studies in 19 publications were identified which met our inclusion criteria. There are ten studies with 866 chronic periodontitis cases and 786 controls for BsmI, 16 studies with 1570 chronic periodontitis cases and 1676 controls for TaqI, five studies with 374 chronic periodontitis cases and 382 controls for FokI, and seven studies with 632 chronic periodontitis cases and 604 controls for ApaI. Overall, no significant association was observed between VDR gene BsmI, TaqI, FokI, and ApaI polymorphisms and risk of chronic periodontitis in any genetic model. Subgroup analysis stratified by ethnicity suggested a significant association between BsmI polymorphism and chronic periodontitis risk in the Caucasian subgroup under allele model (A vs. G: OR = 1.747, 95% CI = 1.099–2.778, P = 0.018). Further, no significant associations were observed when stratified by Hardy–Weinberg equilibrium status for BsmI, TaqI, and ApaI. Conclusion: Our results suggest that BsmI, TaqI, FokI, and ApaI polymorphisms in the VDR gene might not be associated with risk of chronic periodontitis in overall population

ASSOCIATION OF INTERLEUKIN-10 -1082 A/G (RS1800896) POLYMORPHISM WITH SUSCEPTIBILITY TO GASTRIC CANCER: META-ANALYSIS OF 6,101 CASES AND 8,557 CONTROLS

ABSTRACT BACKGROUND: The promoter -1082 A/G (rs1800896) polymorphism of Interleukin-10 (IL-10) gene have been widely reported and considered to have a significant role on gastric cancer risk, but the results are inconsistent. OBJECTIVE: To clarify the association, we conducted a meta-analysis to investigate the associations IL-10 -1082 A/G polymorphism with gastric cancer. METHODS: Eligible articles were identified by searching databases including PubMed, Web of Science, and Google Scholar up to August 03, 2017. Odds ratios (OR) with corresponding 95% confidence intervals (CIs) were used to assess the association. RESULTS: A total of 30 case-control studies with 6,101 cases and 8,557 controls were included in this meta-analysis. Overall, a significant association between IL-10 -1082 A/G polymorphism and gastric cancer risk was observed under the allele model (G vs A: OR=1.305, 95% CI=1.076-1.584; P=0.007), heterozygote model and (GA vs AA: OR=1.252, 95% CI=1.252-1.054; P=0.011) and dominant model (GG+GA vs AA: OR=1.264, 95% CI=1.053-1.516; P=0.012). In the subgroup analysis by ethnicity, increased gastric cancer risk were found in Asians under the allele model (G vs A: OR=1.520, 95% CI=1.172-1.973; P=0.002), homozygote model (GG+GA vs AA: OR=1.571, 95% CI=1.023-2.414; P= 0.039), heterozygote model (GA vs AA: OR=1.465, 95% CI=1.192-1.801; P≤0.001) and dominant model (GG+GA vs AA: OR=1.448, 95% CI=1.152-1.821; P=0.002), but not among Caucasian and Latinos populations. CONCLUSION: These results suggested that the IL-10 -1082 A/G (rs1800896) polymorphism might contribute to the gastric cancer susceptibility, especially among Asians