Antimicrobial andself‐crosslinkingpotential of experimentally developed dioctadecyldimethyl ammonium bromide and riboflavin dentin adhesive

Abstract

The aim of the study is to investigate a new formulation, based on dioctadecyldimethyl ammonium‐bromide (QA) and riboflavin (RF), combining antimicrobial activities and protease inhibitory properties with collagen crosslinking without interference to bonding capabilities in a rabbit model. Quaternary ammonium riboflavin (QARF) experimental adhesives modified with dioctadecyldimethyl ammonium‐bromide and riboflavin were bonded (0.5/1.0/2.0%) to rabbit dentin to investigate for pulpal‐histology, interfacial‐morphology, transmission electron microscopy, mechanical properties, collagen crosslinking, micro‐Raman analysis, antimicrobial, and anti‐protease activities. Collagen type‐I molecules were generated using molecular‐docking. Odontoblasts appeared with normal histology, were seen in controls with no inflammatory cells detected in 0.5% specimens at day 7 and mild inflammatory response at day 30. In QARF 2.0%, inflammatory cells were not detected at day 7 and 30 (p < .05). Dentinal tubules are seen with intact collagen surface in 1% specimens. Resin penetrated inside 1% adhesive specimens with few irregularly funnel‐shaped tags. Transmission electron microscopy showed thinner collagen in all specimens except 1% QARF specimens. Biofilms were influenced by QARF adhesives. Elastic moduli were significantly higher in 1.0% and 2.0% QARF adhesive specimens with a significant increase in total crosslinks. Stable amide groups with anti‐protease activity was observed in QARF groups. Charged residues were seen in the triple helix hCOL3A1, Gly489‐Gly510 after stabilisation with formulation. The 1% QARF modified adhesives improved biochemical and biomechanical properties of rabbit dentin.

MDPB-Containing Self-Etch Dental Adhesive: Antibacterial Activity and Effect of Different Dentinal Surface preparation

“…al. 5 demonstrated that the negatively charged bacterial cell wall comes in contact with the positive antimicrobial arms, incorporating inside the cell membrane, disrupting the osmotic balance and eventual breakage of the cellular wall. There is formed free volume in the cell membrane increasing the intracellular pressure.…”

“…RF has been reported to improve dentin bonding as well, by increasing mechanical properties of the collagen layer. 5 Dentin collagenolytic and gelatinolytic activities can be reduced or suppressed by protease inhibitors. 1 indicating that matrix metalloproteases (MMP) inhibition could be beneficial in the preservation of hybrid layers.…”

Effect of polyhydroxy-terminated PAMAM dendrimer on dentin matrix metalloproteinases within the hybrid layers

“…Another approach is to use collagen cross-linking agents such as riboflavin. The use of cross-linkers has been confirmed to improve the collagen stiffness, tensile strength and compressive modulus by strengthening the interfacial layer through additional hydrogen bonds and formation of covalent intra-and intermolecular crosslinks, and by inhibiting dentin MMPs via masking the cleavage sites of collagen [13][14][15][16][17][18][19][20][21]. Although cross-linker can maintain the integrity of the mineral-denuded collagen matrices, the waterfilled, resin-sparse and flaccid collagen fibrils are prone to cyclic fatigue breakdown after repetitive loads [8].…”