title: Viability of pulp stromal cells in cryopreserved deciduous teeth.
abstract: The cryopreservation of exfoliated deciduous teeth and harvesting of stem cells from them as required would reduce the costs and efforts associated with banking stem cells from primary teeth. The aim of this study was determine whether the viability of pulp stromal cells from deciduous teeth was influenced by the cryopreservation process itself or the period of cryopreservation. In total, 126 deciduous teeth were divided into three groups: (1) fresh, (2) cryopreserved for <3 months (cryo<3), and (3) cryopreserved for 3-9 months (cryo3-9). The viability of the pulp tissues was compared among the three groups by evaluating the outgrowth from pulp tissues and cell activity within those pulp tissues. In addition, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay was performed to compare cell apoptosis within fresh pulp tissue and pulp tissue that had been cryopreserved for 4 months. The outgrowth from and cell activity within the pulp tissues did not differ significantly between the fresh and cryo<3 pulp tissues. However, these parameters were significantly reduced in the cryo3-9 pulp tissue. In TUNEL assay, 4-month cryopreserved pulp tissues has more apoptotic cells than fresh group. In conclusion, it is possible to acquire pulp stromal cells from cryopreserved deciduous teeth. However, as the period of cryopreservation becomes longer, it is difficult to get pulp cells due to reduced cell viability.
authors.affiliation: Department of Pediatric Dentistry, College of Dentistry, Yonsei University, 250 Seongsanno, Seodaemun-gu, Seoul, 120-752, Korea.
authors.forename: Eun Hye
authors.initials: EH
authors.lastname: Ji
authors.forename: Je Seon
authors.initials: JS
authors.lastname: Song
authors.forename: Seong-Oh
authors.initials: SO
authors.lastname: Kim
authors.forename: Mijeong
authors.initials: M
authors.lastname: Jeon
authors.forename: Byung-Jai
authors.initials: BJ
authors.lastname: Choi
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D017209:Apoptosis; D002454:Cell Differentiation; D002469:Cell Separation; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D015925:Cryopreservation; D003782:Dental Pulp / Q000166:cytology*; D005260:Female; D006801:Humans; D020287:In Situ Nick-End Labeling; D008297:Male; D013234:Stem Cells / Q000166:cytology*; D017154:Stromal Cells / Q000166:cytology*; D014094:Tooth, Deciduous / Q000166:cytology*