title: In situ antibiofilm effect of glass-ionomer cement containing dimethylaminododecyl methacrylate.
abstract: OBJECTIVE
  The aim of this study was to investigate antibiofilm effects of a recently developed glass ionomer cement (GIC) containing dimethylaminododecyl methacrylate (DMADDM) under oral conditions.
  
  
  METHODS
  Biofilms were allowed to form in situ on GIC specimens (n=216) which contained DMADDM (1.1wt.% or 2.2wt.%). Samples without DMADDM served as control (n=108). GIC specimens were fixed on custom made splints and exposed to the oral cavity in six healthy volunteers for 24, 48 and 72h, respectively. Biofilm viability and coverage were analyzed by fluorescence microscopy (FM) and evaluated by red/green ratios and an established scoring system. Bacterial morphology and biofilm accumulation were determined by scanning electron microscopy (SEM). Additionally, material properties as surface charge density of quaternary ammonium groups, surface roughness and DMADDM release were recorded.
  
  
  RESULTS
  FM results showed a higher ratio (24h: 0%: 0.5, 1.1%: 1.2, 2.2%: 2.5) of red/green fluorescence on GIC samples containing DMADDM. Biofilm coverage and viability scores were significantly reduced (24h: q1/median/q3 for: 0%: 3/4/5, 1.1%: 2/3/3, 2.2%: 1/2/2) on DMADDM containing samples compared to controls after 24h as well as 48 and 72h in situ (p<0.05). While surface charge density of quaternary ammonium groups and DMADDM release increased with the DMADDM concentration, surface roughness was lowest on specimens containing 2.2wt.% DMADDM.
  
  
  CONCLUSIONS
  An in situ dental biofilm model was used to evaluate the novel GIC containing DMADDM. This material strongly inhibited biofilms in situ and is promising to prevent bacterial colonization on the surface of restorations.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China; Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University Hospital, Homburg/Saar, Germany.
authors.forename: Jin
authors.initials: J
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China. Electronic address: zhouxd@scu.edu.cn.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Biomaterials & Tissue Engineering Division, Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, Baltimore, MD 21201, USA.
authors.forename: Hockin H K
authors.initials: HH
authors.lastname: Xu
authors.affiliation: Biomaterials & Tissue Engineering Division, Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, Baltimore, MD 21201, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Weir
authors.affiliation: Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Meyer
authors.affiliation: Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Maurer
authors.affiliation: Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University Hospital, Homburg/Saar, Germany.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University Hospital, Homburg/Saar, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Hannig
authors.affiliation: Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University Hospital, Homburg/Saar, Germany. Electronic address: stefan.rupf@uks.eu.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rupf
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D004311:Double-Blind Method; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000494:pharmacology*; D050296:Microbial Viability / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D011446:Prospective Studies; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D005899:Glass Ionomer Cements; D008689:Methacrylates; D000644:Quaternary Ammonium Compounds; C586974:dimethylaminododecyl methacrylate; C110713:fuji IX
keywords: Anti-bacterial agents; Biofilms; Dimethylaminododecyl methacrylate; Glass ionomer cements