Reinforcing an immature tooth model using three different restorative materials.

Background: To compare and evaluate the strength rendering capacity of three restorative materials in tooth model simulated as immature teeth. Materials and Methods: In this in vitro study, 80 human maxillary permanent central incisors scheduled for periodontal extraction were collected, and an immature tooth model was prepared using a 3 mm twist drill. To simulate single-visit apical barrier, all the teeth were prepared with peso number 1-6. The teeth were segregated into three experimental and a control group. The experimental groups (n = 20) comprised of fiber-reinforced composite (FRC), Biodentine, and glass ionomer cement. The fracture resistance of all the teeth was tested using universal testing machine. The final reading of the applied load to cause fracture was noted and later was subjected to statistical analysis, P ≤ 0.05 was considered statistically significant, and the level of significance was fixed at 5%. Student's t-test was applied to compare values among experimental groups. Results: There was a significant difference in the values of peak load resulting in fracture among experimental groups which was observed statistically (P ≤ 0.001). FRC exhibited superior reinforcing capacity (mean: 1199.7 N) among the experimental materials followed by Biodentine and Bioglass R. The lowest value to fracture was observed in control group (mean: 236.7 N). Conclusion: The results indicate that FRC could substantially contribute positively in reinforcing the simulated thin-walled immature roots.

Mechanical and antimicrobial property of different surface treated glass ionomer cements under desiccated condition.

BACKGROUND: The purpose of this in vitro study was to evaluate the effect of five different surface treatments on the mechanical property and antimicrobial effect of three desiccated glass ionomer cements. MATERIALS AND METHODS: In this in vitro experimental study, 300 rectangular blocks of three different restorative materials were fabricated using an aluminum mold, Group I (n = 100) Micron bioactive, Group II (n = 100) GC Fuji IX GP Extra, and Group III (n = 100) bioglass R. These blocks were stored in 100% humidity for 24 h and then placed in air to desiccate for another 24 h. These groups were further divided into two major groups (n = 50) for both mechanical (Flexural) and antimicrobial testing. The blocks of mechanical and antimicrobial groups were further divided into five subgroups (n = 10) based on the medias used for surface treatment (senquelNaF, MI varnish, chlorhex plus, kedodent mouthwash, and 100% humidity [control]). Flexural strength (FS) was measured using the universal testing machine. Fracture strength of groups was compared using the one-way analysis of variance and Tukey's post hoc test with P ≤ 0.05 considered statistically significant. Antimicrobial effect was carried out by covering the specimens in a suspension of Streptococcus mutans followed by incubation for 24 h. The blocks were later washed, vortex mixed, serially diluted, and plated. Ccolony-forming unit/ml was calculated after 3 days of incubation. Data were then analyzed using the Kruskal-Wallis and Mann-Whitney U nonparametric test, with P ≤ 0.05 considered statistically significant. RESULTS: Micron bioactive with the surface treatment of MI varnish significantly exhibited highest FS. Surface treatment of desiccated restorative materials with chlorhex plus exhibited no growth of S. mutans. GC Fuji IX GP Extra with surface treatment of MI varnish exhibited highest reduction in S. mutans growth compared to other experimental group. CONCLUSION: Surface treatment of restorative material with MI varnish improved their mechanical and antimicrobial property while among three restorative materials Micron bioactive showed better mechanical property, whereas GC Fuji IX GP Extra exhibited better antimicrobial property.

Evaluation of antibacterial activity of three different glass ionomer cements on streptococcus mutans: an in-vitro antimicrobial study.

AIM: Purpose of this in-vitro study was to assess and compare the antimicrobial activity of three different glass ionomer cements (GIC) against streptococcus mutans (S. mutans) bacteria using agar plate diffusion test. METHODS: Thirty blood agar plates were prepared and three wells of 4mm diameter were made on each agar plate. Three different GIC (Micron bioactive, GC Fuji IX GP Extra, Bioglass r) were mixed and filled into the wells. These plates were inoculated with S. Mutans and incubated at 37°C for 24 hours. Bacterial growth inhibition zone around each well were recorded in millimeters using Hiantibiotic Zonescale-C. RESULT: All the restorative material used in the study exhibited antimicrobial property against S. Mutans. GC Fuji IX GP Extra showed superior antimicrobial efficacy with 17.3±2.6 mm mean diameter of bacterial inhibition zone, followed by Micron bioactive 14.4±1.07 mm and Bioglass r 10.8 ± .91 mm inhibition zone respectively. CONCLUSION: Within the limitation of this study, it can be concluded that all the GIC evaluated demonstrated antibacterial activity against S. mutans. The superior antimicrobial activity was demonstrated by GC Fuji IX GP Extra. Hence, it could be advantageous in patients with high caries risk.