title: Exploring antibacterial activity and hydrolytic stability of resin dental composite restorative materials containing chitosan.
abstract: BACKGROUND
  The development of resin dental composite restorative materials (RDCRM) with antimicrobial activity may prevent the problem of secondary caries and consequently prolong longevity of RDCRM.
  
  
  OBJECTIVE
  This study explored antibacterial activity and hydrolytic stability of RDCRM containing chitosan.
  
  
  METHODS
  The antibacterial activity of microhybrid and flowable RDCRM containing 0, 0.25, 0.5 and 1% wt/wt chitosan (CS) against Lactobacilli casei bacteria was investigated using agar diffusion test and direct contact methods. Hydrolytic stability of experimental RDCRM was evaluated using gravimetric analysis.
  
  
  RESULTS
  The control and experimental flowable and microhybrid RDCRM exhibited no growth inhibition zone in the lawn growth of Lactobacilli casei. The direct contact test revealed that colony forming unit count of Lactobacilli casei was comparable among the experimental and control RDCRM. The water sorption and solubility values of control as well as experimental flowable and microhybrid RDCRM were found to be within the ISO accepted range. There was statistically no significant difference in water sorption and solubility of different experimental RDCRM groups.
  
  
  CONCLUSIONS
  The one percentage of CS into experimental RDCRM have no antibacterial activity against Lactobacilli casei. The hydrolytic stability of RDCRM containing CS was acceptable.
authors.affiliation: Medical Research Centre, Liaquat University of Medical & Health Sciences, Jamshoro, Pakistan.
authors.forename: Shahid
authors.initials: S
authors.lastname: Ali
authors.affiliation: Department of Operative Dentistry, Liaquat University of Medical & Health Sciences, Jamshoro, Pakistan.
authors.forename: Laila
authors.initials: L
authors.lastname: Sangi
authors.affiliation: Department of Science of Dental Materials, Liaquat University of Medical & Health Sciences, Jamshoro, Pakistan.|Department of Restorative Dental Sciences, College of Dentistry, King Faisal University, Al Ahsa, Kingdom of Saudi Arabia.
authors.forename: Naresh
authors.initials: N
authors.lastname: Kumar
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001431:Bacteriological Techniques; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology*; D003188:Composite Resins / Q000737:chemistry / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004355:Drug Stability; D006801:Humans; D007780:Lacticaseibacillus casei / Q000187:drug effects; D008422:Materials Testing; D011140:Polyurethanes / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000180:Acrylic Resins; D000900:Anti-Bacterial Agents; C029012:Composite Dental Resin; D003188:Composite Resins; D011140:Polyurethanes; D048271:Chitosan
keywords: Resin dental composites; antibacterial activity; chitosan; water solubility; water sorption