How Irrigants Affect Mineral Trioxide Aggregate (MTA) Sealing in Furcal Perforations: An In Vitro Study

Objective This study aimed to evaluate the effect of 5.25% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) on ProRoot mineral trioxide aggregate (MTA) used for treating furcal perforations, compared to no solution application, using the dye penetration (DP) method. Materials and methods The study included 36 intact mandibular molars in the furcal area (FA) with well-spaced roots. Using dental operating microscopes, perforations were created at the FA of the molars with a 1.2 mm diameter. Subsequently, ProRoot MTA (Dentsply, Germany) was applied to seal the perforations. After 24 hours, the samples were randomly assigned to three groups: Group A (n = 12), irrigated with 5.25% NaOCl; Group B (n = 12), irrigated with 2% CHX; and Group C (n = 12), without irrigation (control group). Specimens' pulp chambers were immersed in 2% methylene blue for 24 hours. Buccal-lingual sections were performed, and the depth of marginal dye leakage was assessed using a stereomicroscope at 20x magnification. Data analysis employed the one-way analysis of variance (ANOVA) test and Bonferroni post-hoc test (α = 0.05). Results The study revealed significant differences in DP values between groups (p-value < 0.01). DP values in the control group (no irrigation) were lower than both NaOCl (p < 0.05) and CHX (p < 0.01) groups. Furthermore, DP values in the CHX group were higher than those in the NaOCl group (p < 0.01), suggesting the order: no irrigation < NaOCl < CHX (p < 0.05). Conclusions The sealing ability of MTA was compromised when irrigated with 2% CHX and 5.25% NaOCl. CHX significantly impacted the marginal leakage and sealing ability of MTA. Care should be taken when resuming endodontic treatment after the application of MTA in cases of furcal perforations as the use of CHX and NaOCl may affect the marginal leakage of MTA.