Comparative Evaluation of the Effect of Different Matrix Metalloproteinase Inhibitors on Shear Bond Strength between Composite and Dentin: An In Vitro Study.

Background: Matrix metalloproteinases (MMPs) degrade the hybrid layer in dentin bonding, affecting composite restoration longevity. Inhibitors like tetracyclines, chlorhexidine (CHX), and ethylenediaminetetraacetic acid (EDTA) can enhance bond strength. In vitro studies compare these inhibitors' effects on shear bond strength (SBS), aiming to improve clinical outcomes and extend restoration lifespan. Aim and objective: This study aims to compare the effects of different MMP inhibitors on the SBS between composite and dentin using a universal testing machine. Materials and methods: A total of 64 freshly extracted human premolars, free from cracks or defects, were collected, disinfected in 0.5% chloramine T solution, and stored in distilled water for use within 6 months. These premolars, exhibiting normal anatomy and from patients without orthodontic treatment history, were divided into four groups, including a control group. Teeth were meticulously cleaned, embedded in acrylic resin blocks, and underwent prophylaxis with pumice and water. Composite cylinder build-ups were performed on the specimens, and their SBS was measured. Results: SBS among four different MMP inhibitors, with and without thermocycling, shows a significant difference (p = 0.003 and p < 0.001, respectively). Without thermocycling, the control group (10.97 MPa) shows the highest SBS, while 17% EDTA (5.32 MPa) showed the lowest. Similarly, with thermocycling, 2% CHX (10.97 MPa) exhibited the highest SBS, and 17% EDTA (3.92 MPa) showed the lowest. Conclusion: CHX emerged as the most effective MMP inhibitor, with 2% chlorhexidine showing the highest SBS in both thermocycling and nonthermocycling groups, while 17% EDTA showed the lowest. MMP inhibitors, particularly 2% chlorhexidine, help maintain improved dentin bonding durability of adhesive restorations after thermocycling. How to cite this article: Honaje NV, Ninawe N, Anija CK, et al. Comparative Evaluation of the Effect of Different Matrix Metalloproteinase Inhibitors on Shear Bond Strength between Composite and Dentin: An In Vitro Study. Int J Clin Pediatr Dent 2025;18(9):1066-1070.