title: Effect of platelet-rich plasma concentrations on the proliferation of periodontal cells: Anin vitrostudy.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of different concentrations of platelet-rich plasma (PRP) on the proliferation of undifferentiated periodontal ligament (PDL) fibroblasts.
  
  
  METHODS
  The undifferentiated PDL fibroblasts were obtained from two healthy human premolar teeth and cultured in Dulbecco's modified Eagle's medium. Cell wells were divided into five groups. Experimental groups received 0.1%, 5%, or 50% PRP; the positive and negative control groups were cultured in fetal bovine serum (FBS) 12% and in a medium without FBS 12%, respectively. The plates were incubated at 37°C for 1, 2, 3, 4, and 7 days. PDL cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide proliferation assay. Statistical analysis of the data was accomplished using repeated measure ANOVA and Tukey's test.P< 0.05 was considered statistically significant.
  
  
  RESULTS
  The 5% PRP had the greatest effect on undifferentiated fibroblast proliferation, which was significant on the 3rdday. There was no significant difference between 0.1% PRP and positive control during the first 3 days. The group with 50% PRP presented significantly lower proliferation, compared to other experimental and control groups.
  
  
  CONCLUSIONS
  It may be concluded that the growth-stimulating effect of PRP is dose dependent with the best results in low concentrations.
authors.affiliation: Department of Pediatric Dentistry, Dental School, Islamic Azad University, Tehran Branch, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Tavassoli-Hojjati
authors.affiliation: Department of Immunology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mandana
authors.initials: M
authors.lastname: Sattari
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Tayebeh
authors.initials: T
authors.lastname: Ghasemi
authors.affiliation: Department of Pediatric Dentistry, Dental School, Shahed University, Tehran, Iran.
authors.forename: Rahil
authors.initials: R
authors.lastname: Ahmadi
authors.affiliation: Department of Dermatology, Medical School, Islamic Azad University, Markazi, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Mashayekhi
keywords: Avulsion; cell culture; cell proliferation; periodontal ligament cell; platelet-rich plasma