title: Antibacterial and Odontogenesis Efficacy of Mineral Trioxide Aggregate Combined with CO2 Laser Treatment.
abstract: BACKGROUND
  Mineral trioxide aggregate (MTA) has been successfully used in clinical applications in endodontics. Studies show that the antibacterial effects of CO2 laser irradiation are highly efficient when bacteria are embedded in biofilm because of a photothermal mechanism. The aim of this study was to confirm the effects of CO2 laser irradiation on MTA with regard to both material characterization and cell viability.
  
  
  METHODS
  MTA was irradiated with a dental CO2 laser using directly mounted fiber optics in the wound healing mode with a spot area of 0.25 cm(2) and then stored in an incubator at 100% relative humidity and 37°C for 1 day to set. The human dental pulp cells cultured on MTA were analyzed along with their proliferation and odontogenic differentiation behaviors.
  
  
  RESULTS
  The results indicate that the setting time of MTA after irradiation by the CO2 laser was significantly reduced to 118 minutes rather than the usual 143 minutes. The maximum diametral tensile strength and x-ray diffraction patterns were similar to those obtained without CO2 laser irradiation. However, the CO2 laser irradiation increased the amount of Ca and Si ions released from the MTA and regulated cell behavior. CO2 laser-irradiated MTA promoted odontogenic differentiation of hDPCs, with the increased formation of mineralized nodules on the substrate's surface. It also up-regulated the protein expression of multiple markers of odontogenic and the expression of dentin sialophosphoprotein protein.
  
  
  CONCLUSIONS
  The current study provides new and important data about the effects of CO2 laser irradiation on MTA with regard to the decreased setting time and increased ion release. Taking cell functions into account, the Si concentration released from MTA with laser irradiation may be lower than a critical value, and this information could lead to the development of new regenerative therapies for dentin and periodontal tissue.
authors: Institute of Oral Science, Chung Shan Medical University Hospital, Taichung City, Taiwan.
authors: Tuan-Ti
authors: TT
authors: Hsu
authors: 3D Printing Medical Research Center, China Medical University Hospital, Taichung City, Taiwan.
authors: Chia-Hung
authors: CH
authors: Yeh
authors: School of Dentistry, Chung Shan Medical University Hospital, Taichung City, Taiwan; Department of Stomatology, Chung Shan Medical University Hospital, Taichung City, Taiwan.
authors: Chia-Tze
authors: CT
authors: Kao
authors: 3D Printing Medical Research Center, China Medical University Hospital, Taichung City, Taiwan.
authors: Yi-Wen
authors: YW
authors: Chen
authors: School of Dentistry, Chung Shan Medical University Hospital, Taichung City, Taiwan; Department of Stomatology, Chung Shan Medical University Hospital, Taichung City, Taiwan.
authors: Tsui-Hsien
authors: TH
authors: Huang
authors: Institute of Oral Science, Chung Shan Medical University Hospital, Taichung City, Taiwan.
authors: Jaw-Ji
authors: JJ
authors: Yang
authors: 3D Printing Medical Research Center, China Medical University Hospital, Taichung City, Taiwan. Electronic address: eviltacasi@gmail.com.
authors: Ming-You
authors: MY
authors: Shie
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D017610:Calcium Compounds / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003782:Dental Pulp / Q000166:cytology* / Q000187:drug effects / Q000528:radiation effects; D004338:Drug Combinations; D006801:Humans; D007477:Ions; D054020:Lasers, Gas / Q000627:therapeutic use; D009805:Odontogenesis / Q000187:drug effects* / Q000528:radiation effects*; D010087:Oxides / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D017640:Silicates / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects
chemical_list: D017607:Aluminum Compounds; D000900:Anti-Bacterial Agents; D017610:Calcium Compounds; D004338:Drug Combinations; D007477:Ions; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; C031293:calcium silicate
keywords: Antibacterial; CO(2) laser; human dental pulp cell; mineral trioxide aggregate; odontogenic