Effects of Chlorhexidine and Sodium Hypochlorite on the Setting Time of Calcium-Enriched Mixture Cement

Effects of White Chicken Eggshell Powder on Compressive Strength, Water Solubility, and Setting Time of Calcium-Enriched Mixture

Introduction

The present study aimed to evaluate the effects of adding chicken eggshell powder (CESP) to calcium-enriched mixture (CEM) cement on its compressive strength (CS), solubility, and setting time.

Materials and Methods

In this study, CESP was added at weight percentages of 3% and 5% to the powder component of the CEM cement. To measure the CS, a total of 36 samples (height, 6 mm; diameter, 4 mm) were tested in a universal testing machine. The setting time was assessed for 18 disk-shaped samples (diameter, 10 mm; height, 1 mm). Additionally, solubility test was performed on 18 samples (diameter, 8 mm; height, 1 mm) after 24 hours, 72 hours, seven days, and 14 days under dehydration conditions by calculating the weight changes; the results were then subjected to a normality test. Next, for the comparison of different test groups, parametric ANOVA test and post-hoc Tukey's multiple comparison test were performed at a significance level of 0.05.

Results

The addition of 5% CESP to the CEM cement significantly reduced its setting time and water solubility (P=0.02 and P=0.01, respectively). Moreover, it significantly increased the CS over a 21-day period (P<0.001). Additionally, the addition of 3% CESP also resulted in a significant increase in CS (P<0.001). While 3% CESP reduced setting time and water solubility, the difference was not statistically significant.

Conclusion

The findings suggest that the addition of 5% CESP to CEM cement has the potential to improve its sealing ability, durability, and ability to withstand chewing forces in endodontic treatments. These results highlight the relevance of CESP as an additive for cement modifications and indicate its potential clinical implications.

Effect of the of Zeolite Containing Silver-Zinc Nanoparticles on the Push out Bond Strength of Mineral Trioxide Aggregate in Simulated Furcation Perforation

STATEMENT OF THE PROBLEM

Recently, zeolite has been regarded to improve the properties of dental materials such as mineral trioxide aggregate (MTA).

PURPOSE

The aim of the present study was to evaluate the effect of incorporating zeolite/silver/zinc (Ze/Ag/Zn) composite at 2 wt% to MTA powder on the push-out bond strength in simulated furcation perforations.

MATERIALS AND METHOD

Furcal perforations, measuring 1.3 mm in diameter and 2 mm in height, were simulated in 40 human mandibular first molars. The samples were allocated to two groups (n=20) based on the material used for the repair of perforations. In the group 1, MTA and in the group 2, MTA plus Ze/Ag/Zn (2%) was used. The samples were incubated at 37°C for 1 week. Then the universal testing machine was employed to measure bond strength. The resistance of materials to dislodgment was recorded in MPa. Data were analyzed using t-test. Statistical significance was set at p< 0.05.

RESULTS

The push-out bond strength in the group 1 (6.40±1.98 MPa) was significantly higher than that in the group 2 (2.1±0.6 MPa) with p= 0.001.

CONCLUSION

Under the limitations of the present study, it can be concluded that incorporation of Ze/Ag/Zn at 2 wt% to MTA powder had a negative effect on the push-out bond strength.

Effect of Calcium Hydroxide on the Push-out Bond Strength of Endodontic Biomaterials in Simulated Furcation Perforations

Introduction:

The aim of this in vitro study was to evaluate the effect of calcium hydroxide (CH) on push-out bond strength of white mineral trioxide aggregate (WMTA) and calcium-enriched mixture (CEM) cement in simulated furcation perforations.

Methods and Materials:

Furcation perforations, measuring 1.3 mm in diameter and 2 mm in height, were created in 80 human mandibular first molars. The teeth were then divided into 4 groups (n=20). In groups 1 and 3 CH was placed in the perforation for one week, before placement of WMTA and CEM. In groups 2 and 4 perforations were repaired without placement of CH. In groups 1 and 2 the perforation sites were repaired with WMTA and CEM cement was used in groups 3 and 4. After 7 days, the push-out test was carried out using a universal testing machine. Data were analyzed with two-way ANOVA. The level of significance was set at 0.05.

Results:

The maximum and minimum bond strength values were recorded in the WMTA/CH (13.08±1.8 MPa) and CEM cement groups (8.03±0.98 MPa), respectively. There were significant differences in resistance to dislodgement between the WMTA/CH and other groups (P<0.05).

Conclusion:

Placement of CH before placement of WMTA in furcation perforation improves the push-out bond strength of this material.