title: Assessment of Pulp Regeneration Induced by Stem Cell Therapy by Magnetic Resonance Imaging.
abstract: BACKGROUND
  This study was designed to evaluate the usefulness of magnetic resonance imaging (MRI) to assess the regeneration of pulp tissue.
  
  
  METHODS
  Mobilized dental pulp stem cells and granulocyte colony-stimulating factor with collagen were transplanted into mature pulpectomized teeth for pulp regeneration (n = 4). The controls consisted of pulpectomized teeth with or without collagen and normal teeth with intact pulp tissue (n = 4, each). The signal intensity (SI) of MRI using T2 sequences was compared after the extraction of teeth in dogs. MRI was correlated with the corresponding histologic findings.
  
  
  RESULTS
  Pulp tissue was fully regenerated 90 days after cell transplantation. On the other hand, the root canal was empty in the control collagen-transplanted teeth at 90 days. The SI of the normal teeth was significantly higher than that of nonvital pulpectomized teeth and the controls of collagen transplanted teeth at 90 days. The stem cell transplanted teeth showed a gradual decrease in the SI until 180 days at which time the SI was similar to that in the normal teeth and significantly higher than that in the teeth transplanted with collagen alone without the stem cells.
  
  
  CONCLUSIONS
  The changes in the SI of the pulplike tissue were consistent with the histologic findings, showing the potential usefulness of the noninvasive method to serially access the efficacy of pulp regenerative therapy.
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, National Center for Geriatrics and Gerontology, Research Institute, Obu, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Iohara
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, National Center for Geriatrics and Gerontology, Research Institute, Obu, Japan; Department of Endodontology, School of Dentistry, Aichi-gakuin University, Nagoya, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Fujita
authors.affiliation: Department of Oral and Maxillofacial Radiology, School of Dentistry, Aichi-gakuin University, Nagoya, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ariji
authors.affiliation: Department of Aging Neurobiology, Center of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Research Institute, Obu, Japan.
authors.forename: Misato
authors.initials: M
authors.lastname: Yoshikawa
authors.affiliation: Institute for Molecular Science of Medicine, Aichi Medical University, Nagakute, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Watanabe
authors.affiliation: Department of Aging Neurobiology, Center of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Research Institute, Obu, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Takashima
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, National Center for Geriatrics and Gerontology, Research Institute, Obu, Japan. Electronic address: misako@ncgg.go.jp.
authors.forename: Misako
authors.initials: M
authors.lastname: Nakashima
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D003481:Cuspid / Q000166:cytology / Q000187:drug effects / Q000254:growth & development; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D003786:Dental Pulp Cavity / Q000033:anatomy & histology / Q000166:cytology; D004285:Dogs; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D023421:Models, Animal; D011897:Random Allocation; D012038:Regeneration / Q000187:drug effects / Q000502:physiology*; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*
chemical_list: D016179:Granulocyte Colony-Stimulating Factor
keywords: Efficacy; MRI; pulp regeneration