Spectrophotometric analysis of the color stability of white mineral trioxide aggregate in contact with four different irrigating solutions - An in vitro study.

AIMS: This study aims to compare the color stability of white mineral trioxide aggregate (wMTA) in contact with four irrigating solutions. SETTINGS AND DESIGN: Original research study. SUBJECTS AND METHODS: Fifty cylindrical discs of wMTA, 10 mm in diameter and 2 mm in height were prepared using a mold. Samples were incubated at a temperature of 37°C and at 100% humidity for the material to reach its optimal mechanical properties. The samples were divided into 6 groups: Group A: dry (n = 5); Group B: distilled water (DW) (n = 5); Group C: 5% sodium hypochlorite (NaOCl) (n = 10); Group D: 2% chlorhexidine gluconate (CHX) (n = 10); Group E: 17% aqueous ethylene diamine tetra-acetic acid (EDTA) (n = 10); Group F: 0.2% Chitosan (n = 10) Each disc was immersed into the irrigating solution for a period of 24 h. All the specimens were photographed using a digital camera before and after immersion. The assessment of color change of each disc of wMTA was conducted by a spectrophotometer. The Commission Internationale de l'eclairage system was used to calculate the differences in color. STATISTICAL ANALYSIS USED: Statistical Package for the Social Sciences version 16.0 (Chicago, IL, USA) at a significance level of P < 0.05 was used. RESULTS: All groups except group A exhibited discoloration of wMTA. The mean values for change in color was highest with Group D, followed by Group C, F, E, B, and group A. Only Group B when compared to group A did not show any statistically significant difference (P = 0.948) whereas all the other four groups showed a highly statistically significant difference (P < 0.001). CONCLUSIONS: 2% CHX causes maximum discoloration of wMTA followed by 5% NaOCl, 0.2% Chitosan and least discoloration with 17% aqueous EDTA and DW.

Micro-computed tomographic analysis of the marginal adaptation of a calcium silicate-based cement to radicular dentin after removal of three different intracanal medicaments - An in vitro study.

CONTEXT: This study focuses on the marginal adaptation of a calcium silicate-based cement to the root dentin after retrieval of different intracanal medicaments. AIM: This study compared the marginal adaptation of a calcium silicate-based cement to radicular dentin in the apical third of the root canal following the use of three different intracanal medicaments. MATERIALS AND METHODS: Forty single-rooted premolar teeth (n = 40) were decoronated 13 mm above the root apices; then, 3 mm of the root tips were resected to standardize the root length. Orthograde cleaning and shaping were done using the rotary files and apical enlargement using peeso reamers. Depending on the intracanal medicament used, the samples were equally divided into four groups: Group 1 - control, Group 2 - Metapex, Group 3 - triple antibiotic paste (TAP), and Group 4 - calcium hydroxide with Propolis. Subsequently, the medicament was removed and a 3 mm apical barrier of BiodentineTM was placed and later scanned using an ex vivo micro-computed tomography scanner. STATISTICAL ANALYSIS USED: One-way ANOVA F-test and Tukey's post hoc test were used. RESULTS: Maximum adaptation was seen in control group (0.65) > Propolis (1.47) > TAP (4.37) > Metapex (5.25); a high statistically significant difference between the four groups was found (P < 0.001) with regard to the external voids between BiodentineTM and radicular dentin. CONCLUSION: On comparison of the marginal adaptation of Biodentine to root canal dentin following the use of three different intracanal medicaments, maximum adaptation was seen in Group 1, followed by Group 4, Group 3, and Group 2.

Scanning electron microscopic evaluation of smear layer removal at the apical third of root canals using diode laser, endoActivator, and ultrasonics with chitosan: An in vitro study.

AIM: The aim of this study was to compare the effect of diode laser, endoActivator, and passive ultrasonics for smear layer removal at the apical third from root canals with 0.2% chitosan. MATERIALS AND METHODS: A total of 40 mandibular premolars were decoronated to establish a working length of 12 mm and shaped with ProTaper rotary files up to size F3. In Group A, canals were irrigated with 1 ml of 0.2% chitosan. In Group B, canals were initially irrigated with 0.8 ml of 0.2% chitosan and the remaining 0.2 ml was activated with diode laser. In Group C, canals were irrigated with 1 ml of 0.2% chitosan which was activated with endoActivator. In Group D, canals were irrigated with 0.2% chitosan and activated with passive ultrasonics. All samples were finally flushed with 3 ml of distilled water. The percentage of smear layer removal was analyzed with a scanning electron microscope examination at ×1000 and ×3000. Data were analyzed using Statistical Package for the Social Sciences version 16.0 (SPSS Inc., Chicago, IL, USA) at a significance level of P < 0.05. RESULTS: The mean value for Group B when compared to Group C for the removal of smear layer was higher, but there was no statistically significant difference between the two groups (P < 0.068 and P < 0.295). Both Group B and Group C showed a statistically significant difference (P < 0.001) when compared to Group A and Group D for the removal of smear layer. CONCLUSION: Diode laser and endoActivator with 0.2% chitosan proved better in the removal of the smear layer when compared to passive ultrasonic irrigation.