Vol. 11, Issue 3, Part F (2025)

Background: The restoration of non-vital teeth with extensive coronal destruction poses a significant clinical challenge due to compromised structural integrity and the risk of bacterial recontamination. Achieving an effective coronal seal while preserving remaining tooth structure is critical for long-term endodontic success.

Objective: This study aimed to evaluate and compare the micro-tensile bond strength (μTBS) of flowable short fiber-reinforced resin composite (FSFRRC) to root dentin following disinfection with four different agents: 2% Chlorhexidine (CHX), 17% Ethylenediaminetetraacetic acid (EDTA), 5.25% Sodium hypochlorite (NaOCl), and diode laser-activated photodynamic therapy (PDT) using Toluidine Blue.

Materials and Methods: Forty extracted single-rooted human mandibular premolars were prepared and obturated using standardized endodontic protocols. Post spaces were disinfected with the assigned agents, and 4 mm of FSFRRC was placed and light-cured. Micro-tensile bond strength testing was conducted on sectioned dumbbell-shaped specimens using a universal testing machine, and results were statistically analyzed using one-way analysis of variance (ANOVA).

Results: The NaOCl and CHX groups showed lower μTBS values, with no statistically significant difference between them. The EDTA group exhibited significantly higher bond strength compared to NaOCl and CHX and was statistically comparable to the PDT group. PDT demonstrated significantly higher μTBS than both CHX and NaOCl, indicating enhanced bonding performance.

Conclusion: Disinfection protocol plays a critical role in influencing the bonding efficacy of FSFRRC to root dentin. Both 17% EDTA and PDT enhanced micro-tensile bond strength, while NaOCl was associated with reduced bonding performance despite its antimicrobial advantages.