Evaluating the Effect of CPP-ACP as a Final Irrigant in Improving the Micro-Hardness of Erosive Root Dentin and its Influence on the Bond Strength of Self Etch Resin Sealer - An In-vitro Study

Antibacterial Efficacy of Casein Phosphopeptide-Amorphous Calcium Phosphate Compared to Calcium Hydroxide as Intracanal Medicaments against Enterococcus faecalis: In-vitro Study

Background:

Endodontic infection may persist despite root canal instrumentation. Thus, the use of intracanal medicaments plays an essential role in eliminating resistant bacteria like Enterococcus faecalis, known to be associated with persistent infections in endodontically treated teeth. Although calcium hydroxide is the gold standard intracanal medicament, it has been reported that Enterococcus faecalis is immune to its effects. Therefore, several studies assessed the efficacy of other intracanal medicaments, but none to date evaluated Casein Phosphopeptide-Amorphous Calcium Phosphate.

Objectives:

This in-vitro randomized controlled study aimed to assess the antibacterial efficacy of Casein phosphopeptide-amorphous calcium phosphate as an intracanal medicament against Enterococcus faecalis and compared it to calcium hydroxide.

Methods:

60 extracted single root canal permanent teeth were prepared and later divided into three equal groups according to the intracanal medicament used. Group 1: No intracanal medicament (negative control), Group 2: Calcium hydroxide paste, and Group 3: Casein phosphopeptide-amorphous calcium phosphate paste. The intracanal medicaments were placed on the canals for 7 days. The outcome of this procedure was measured by counting colony-forming units. Statistical analysis was carried out using One-Way ANOVA and Tukey’s Post Hoc Test to determine significant differences between the groups.

Results:

The mean bacterial count for Group 2 was significantly lower than Group 1 and Group 3. Calcium hydroxide showed significantly more antibacterial efficacy against Enterococcus faecalis than Casein phosphopeptide-amorphous calcium phosphate and the negative control groups.

Conclusion:

Casein Phosphopeptide-amorphous calcium phosphate is ineffective in inhibiting Enterococcus faecalis growth compared to Calcium hydroxide.

Adjunctive procedure with solvent mixtures in non-surgical endodontic retreatment: does it affect root dentin hardness?

The aim of this study was to compare the effects of new irrigation solvent mixtures with Methyl ethyl ketone (MEK)/Tetrachloroethylene (TCE) and MEK/Orange oil (OOil), and different agitation techniques on dentin hardness. One hundred forty-four mandibular teeth were prepared and standardized, with each root's middle part transversely sectioned. Initial hardness was measured using a Vickers microhardness tester. Specimens were divided into four groups of agitation techniques (n = 36): no agitation; EndoActivator; IrriSafe; and XP-endo Finisher R. Each group was subdivided into six subgroups of irrigation protocols (n = 6): saline solution; NaOCl + EDTA; NaOCl + EDTA + MEK/TCE; MEK/TCE; NaOCl + EDTA + MEK/OOil; MEK/OOil. Final hardness was measured. The irrigation protocols NaOCl + EDTA, NaOCl + EDTA + MEK/TCE, and NaOCl + EDTA + MEK/OOil significantly decreased dentin hardness, while MEK/OOil increased it (p < 0.05). Comparing to NaOCl + EDTA sequence, dentin hardness increased significantly with the additional exposure to MEK/TCE (3%NaOCl + 17%EDTA + MEK/TCE) or MEK/OOil (3%NaOCl + 17%EDTA + MEK/OOil) (p < 0.05). There were no significant differences regarding agitation effects on dentin hardness decrease. The irrigation protocols affected dentin hardness significantly. However, the additional solvent proposals do not seem to address further concerns on dentin's mechanical properties. Agitation did not show any influence on dentin's hardness reduction.