pH-dependent delivery of chlorhexidine from PGA grafted mesoporous silica nanoparticles at resin-dentin interface

Abstract Background A low pH environment is created due to the production of acids by oral biofilms that further leads dissolution hydroxyapatite crystal in tooth structure significantly altering equilibrium. Although overall bacterial counts may not be eradicated from cavity, however, synthesis engineered anti-bacterial materials are warranted reduce pathogenic impact biofilms. The purpose this study was synthesize and characterize chlorhexidine (CHX)-loaded mesoporous silica nanoparticles (MSN) grafted with poly-L-glycolic acid (PGA) test vitro drug release various environments, cytotoxicity, antimicrobial capacity. In addition, aimed investigate delivery CHX-loaded/MSN-PGA through demineralized dentin tubules how these interact after mixing commercial adhesive for potential clinical application. Results Characterization using SEM/TEM EDX confirmed CHX-loaded/MSN-PGA. An increase percentage encapsulation efficiency 81 85% CHX loaded/MSN 92–95% loaded/MSN-PGA proportionately increased increasing amount during fabrication nanoparticles. For both time-periods (24 h or 30 days), relative microbial viability decreased content ( P < 0.001). Generally, cell DPSCs exposed MSN-PGA/Blank, CHX-loaded/MSN, CHX-loaded/MSN-PGA, respectively > 80% indicating cytotoxicity profiles experimental After 9 months artificial saliva (pH 7.4), highest micro-tensile bond strength value recorded 25:50 CHX/MSN 25:50:50 CHX/MSN-PGA. homogenous widely distributed 50:50:50 exhibited excellent bonding application commercially available adhesive. Conclusions pH-sensitive response noted when loaded MSN PGA formulated drug-loaded nanocarrier demonstrated physicochemical, spectral, biological characteristics. Showing considerable capacity penetrate effectively inside dentinal having high antibacterial efficacy, system could potentially used restorative dentistry.