Comparative evaluation of coronal discoloration induced by two triple antibiotic revascularization protocols when used at varying depths of temporary sealing material at the end of varying time periods

Assessment of Nitrofurantoin as an Experimental Intracanal Medicament in Endodontics

Background and Objectives. Multiple antibacterial agents have been mixed and used as an intracanal medicament-like modified triple antibiotic paste (MTAP) to eliminate Enterococcus faecalis (EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of Materials and Methods. Three strains of EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of n = 90), group M (MTAP) (n = 90), group M (MTAP) (n = 90), group M (MTAP) (EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of n = 90), group M (MTAP) (n = 90), group M (MTAP) (n = 90), group M (MTAP) (EF), which has been most frequently identified in the cases of failed root canal treatment and periapical lesions. This study is aimed at using a single antibacterial agent, nitrofurantoin (Nit), as an experimental intracanal medicament paste against different clinical isolates of

The Effect of Bleaching Agents on the Microstructure and Surface Microhardness of Three Calcium Silicate-Based Barrier Materials

Introduction

The aim of this study was to evaluate the effects of exposure to sodium perborate and H₂O₂ on the surface characteristics of MTA Angelus, Biodentine and MTA Repair HP after 1 and 6 month time intervals.

Methods and Materials

Three calcium silicate-based cements were evaluated: MTA Angelus, Biodentine, MTA Repair HP. A total of 234 specimens were stored in Hank's balanced salt solution (HBSS) for 1 month or 6 months in which afterwards were divided into 3 groups according to bleaching agent applied: control, sodium perborate, 35% hydrogen peroxide. The microstructural changes were evaluated by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The surface microhardness was also evaluated. Data were analyzed by one-way analysis of variance and Games-Howell post-hoc tests for the effect bleaching agents and hydraulic calcium silicate-based cements and t-test was for the effect of time.

Results

Distinctive alterations with uneven depression areas, woodpecker defects and cracks were seen due to exposure to perborate and H₂O₂ on all evaluated cements. Exposure to H₂O₂ caused a decrease in Ca/Si ratio in all experimental cements. Both H₂O₂ and perborate significantly decreased the microhardness of all cement (P<0.05) with H₂O₂ having a more profound effect (P<0.01). A 6-month delay in exposure to bleaching agents significantly increased the microhardness of Biodentine compared to 1 month (P<0.001 for both bleaching agents).

Conclusion

Based on this in vitro study, H₂O₂ had more detrimental effects on MTA Angelus, Biodentine and MTA Repair HP. Sodium perborate may be a more conservative selection when considering effects on barrier materials.