Cleaning efficacy and debris extrusion of supplementary file systems XP-endo Finisher and XP-endo Finisher R in endodontic retreatment.

Aim: To evaluate cleaning efficacy and debris extrusion of supplementary file systems XP Endo Finisher (XPEF) and XP Endo Finisher R (XPEFR) in endodontic retreatment. Materials and Methods: Thirty single-rooted teeth with single canals were selected, canal preparation done till file #30 6% and obturation completed using lateral condensation technique with AH Plus sealer. The samples were stored at 37°C in a 100% humidity incubator for 7 days. The samples were distributed across the three groups according to the method of retreatment (n = 10): Group I: Neo Endo retreatment (NER) files, Group II: NER files + XPEF, and Group III: NER files + XPEFR. Removal of gutta percha using each file system according to the distributed groups was performed. The extruded debris was collected in an Eppendorf tube, dried in a hot air oven, and weighed. Teeth were sliced longitudinally using carborundum discs. Coronal, middle, and apical thirds were assessed for cleaning efficacy under a stereomicroscope. Results were tabulated and subjected to the statistical analysis using the Kruskal-Wallis H-test followed by post hoc turkey HSD test. All statistical tests were carried out at significance level P < 0.05. Results: It was seen that Group II (NER files + XPEF) exhibited better cleaning efficacy than Group III (NER files + XPEFR), although the results were not statistically significant. Greater debris extrusion was seen with Group III when compared to Group II. Conclusion: Supplementary files XPEF/XPEFR enhance the cleaning efficacy in endodontic retreatment, but the debris extrusion of XPEFR is more than XPEF.

The Effect of Matrix Metalloproteinase Inhibitors on the Microtensile Bond Strength of Dentin Bonding Agents in Caries Affected Dentin: A Systematic Review.

Aims and Objectives: Matrix metalloproteinases (MMPs) cause degradation of the dentinal matrix, as they act actively on collagen fibrils, leading to their deterioration and collapse. MMP inhibitors are known to be used for the pre-treatment of human dentin before bonding. Most studies on the MMP inhibitors examined the effect of MMP inhibitors on bonding to sound dentin (SD), but few examine their effect on bonding to caries affected dentin (CAD). This systematic review aims to identify and summarize studies that have applied MMP inhibitors for pre-treatment of CAD, and examine the microtensile bond strength (µTBS), bond durability, and the mode of failure. Materials and Methods: A systematic review was performed using the PubMed database according to the PRISMA guidelines. A total of 785 original articles published between 2010 and 2022 were initially retrieved. Six studies were selected based on predefined inclusion-exclusion criteria, and their outcomes were extracted and analyzed. The methodological quality assessment was performed using a combined checklist that utilizes the reporting criteria mentioned in the checklist for reporting in-vitro studies guidelines and guidelines for reporting pre-clinical in vitro studies on dental materials. Results: All six studies included here showed a definitive increase of the µTBS when MMP inhibitors were applied to the CAD. The mode of failure was found to be predominantly adhesive in nature. The deviation in the values of µTBS was approximately 2-5 MPa on immediate and delayed testing. Conclusion: MMP-inhibiting agents could be considered for the pretreatment of teeth with CAD as a part of their tooth preparation area, thereby allowing the clinician to retain CAD and bond to the CAD without endangering the vital pulp.