Experimental and Theoretical Investigation of Multispecies Oral Biofilm Resistance to Chlorhexidine Treatment.
We investigate recovery of multispecies oral biofilms following chlorhexidine gluconate (CHX) and CHX with surface modifiers (CHX-Plus) treatment. Specifically, we examine the percentage of viable bacteria in the biofilms following their exposure to CHX and CHX-Plus for 1, 3, and 10 minutes, respectively. Before antimicrobial treatment, the biofilms are allowed to grow for three weeks. We find that (a). CHX-Plus kills bacteria in biofilms more effectively than the regular 2% CHX does, (b). cell continues to be killed for up to one week after exposure to the CHX solutions, (c). the biofilms start to recover after two weeks, the percentage of the viable bacteria recovers in the 1 and 3 minutes treatment groups but not in the 10 minutes treatment group after five weeks, and the biofilms fully return to the pretreatment levels after eight weeks. To understand the mechanism, a mathematical model for multiple bacterial phenotypes is developed, adopting the notion that bacterial persisters exist in the biofilms together with regulatory quorum sensing molecules and growth factor proteins. The model reveals the crucial role played by the persisters, quorum sensing molecules, and growth factors in biofilm recovery, accurately predicting the viable bacterial population after CHX treatment.
Division of Endodontics, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada.
Ya
Y
Shen
Department of Mathematics, University of South Carolina, Columbia, SC 29208, USA.
Jia
J
Zhao
Centre for Microbial Diseases and Immunity Research, Department of Microbiology and Immunology, University of British Columbia, Vancouver, V6T 1Z3 Canada.|Synthetic Biology Group, MIT Synthetic Biology Center, Research Laboratory of Electronics, Department of Biological Engineering, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
César
C
de la Fuente-Núñez
Division of Endodontics, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada.
Zhejun
Z
Wang
Centre for Microbial Diseases and Immunity Research, Department of Microbiology and Immunology, University of British Columbia, Vancouver, V6T 1Z3 Canada.
Robert E W
RE
Hancock
Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada.
Clive R
CR
Roberts
Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 China.
Jingzhi
J
Ma
School of Mathematical Sciences, Nankai University, Tianjin 300071, China.
Jun
J
Li
Division of Endodontics, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada.
Markus
M
Haapasalo
Department of Mathematics, University of South Carolina, Columbia, SC 29208, USA.|Beijing Computational Science Research Center, Beijing 100193, China and School of Materials Science and Engineering, Nankai University, Tianjin 300071, China.
Qi
Q
Wang
D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002710:Chlorhexidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects; D018613:Microscopy, Confocal; D009059:Mouth Diseases / Q000188:drug therapy* / Q000382:microbiology; D053038:Quorum Sensing / Q000187:drug effects; D013499:Surface Properties
D000900:Anti-Bacterial Agents; C010882:chlorhexidine gluconate; D002710:Chlorhexidine