Antibacterial, chemical and physical properties of sealants with polyhexamethylene guanidine hydrochloride

Abstract The aim of this study was to evaluate the influence of polyhexamethylene guanidine hydrochloride (PHMGH) in the physico-chemical properties and antibacterial activity of an experimental resin sealant. An experimental resin sealant was formulated with 60 wt.% of bisphenol A glycol dimethacrylate and 40 wt.% of triethylene glycol dimethacrylate with a photoinitiator/co-initiator system. PHMGH was added at 0.5 (G0.5%), 1 (G1%), and 2 (G2%) wt.% and one group remained without PHMGH, used as control (GCTRL). The resin sealants were analyzed for degree of conversion (DC), Knoop hardness (KHN), and softening in solvent ( Δ KHN), ultimate tensile strength (UTS), contact angle ( θ ) with water or α -bromonaphthalene, surface free energy (SFE), and antibacterial activity against Streptococcus mutans for biofilm formation and planktonic bacteria. There was no significant difference for DC (p> 0.05). The initial Knoop hardness ranged from 17.30 ( ±0.50) to 19.50 (± 0.45), with lower value for GCTRL (p< 0.05). All groups presented lower KHN after immersion in solvent (p< 0.05). The Δ KHN ranged from 47.22 ( ± 4.30) to 57.22 (± 5.42)%, without significant difference (p> 0.05). The UTS ranged from 54.72 ( ± 11.05) MPa to 60.46 (± 6.50) MPa, with lower value for G2% (p< 0.05). PHMGH groups presented no significant difference compared to GCTRL in θ (p> 0.05). G2% showed no difference in SFE compared to GCTRL (p> 0.05). The groups with PHMGH presented ...
Source: Brazilian Oral Research - Category: Dentistry Source Type: research