title: Growth kinetics and characterization of human dental pulp stem cells: Comparison between third molar and first premolar teeth.
abstract: BACKGROUND
  Dental pulp stem cells (DPSCs) play an important role in tissue regeneration. This study compares the growth kinetics and characterization of third molar and first premolar human DPSCs.
  
  
  METHODS
  Dental pulp tissues were isolated from human first premolar and third molar teeth and were digested by treating them with collagenase type I. Single-cell suspensions from each dental pulp were seeded in T25 culture flasks and the media were replaced every 3 days until 70% confluence. The cells were enumerated to determine the population doubling time (PDT). Cells were characterized using flow cytometry, RT-PCR and osteogenic medium for differentiation of DPSCs. Karyotyping assay was also performed till passage 7th.
  
  
  RESULTS
  The DPSCs had spindle-shaped morphology. There was an increase in PDT in third molar DPSCs when compared to first premolar teeth. Positive expression of CD44, CD73, and CD90 and negative expression of CD34 and CD45 were illustrated. A normal karyotype was visible for all seven passages. The Alizarin red staining was positive for osteogenic induction of DPSCs.
  
  
  CONCLUSIONS
  When DPSCs are needed, third molar teeth can be a good and convenient candidate for cell transplantation, yielding high number of cells with mesenchymal characteristics. They can be a source for further investigationsin vitroand work on tissue engineering protocols.Key words:Stem cells, dental pulp, growth kinetics, characterization.
authors.affiliation: Assistant Professor of Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Assistant Professor of Department of Developmental Biology, Science and Research Branch, Islamic Azad University, Fars, Iran; Assistant Professor of Department of Regenerative Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Davood
authors.initials: D
authors.lastname: Mehrabani
authors.affiliation: Assistant Professor of Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Parisa
authors.initials: P
authors.lastname: Mahdiyar
authors.affiliation: Associate Professor of Department of Fixed Prosthodontics, Faculty of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Kianoosh
authors.initials: K
authors.lastname: Torabi
authors.affiliation: Assistant Professor of Department of Developmental Biology, Science and Research Branch, Islamic Azad University, Fars, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Robati
authors.affiliation: Assistant Professor of Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Shahrokh
authors.initials: S
authors.lastname: Zare
authors.affiliation: Assistant Professor of Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Assistant Professor of Department of Medical Genetics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Dianatpour
authors.affiliation: Assistant Professor of Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Amin
authors.initials: A
authors.lastname: Tamadon