title: Histologic examinations of teeth treated with 2 scaffolds: a pilot animal investigation.
abstract: BACKGROUND
  A growing body of evidence is building a case for the possibility of tissue regeneration within the root canal of necrotic teeth, allowing for continued root development. However, it remains unknown what type of tissue is produced after regenerative endodontics. The purpose of this study was to use blood clots and platelet-rich plasma (PRP) as scaffolds in regenerative endodontics under ideal conditions in a ferret model to examine the tissues generated within the root canals.
  
  
  METHODS
  The pulps of 21 canine teeth from 7 young ferrets were extirpated using broaches without filing the canal walls. Bleeding was stimulated from the periapical tissues, and a blood clot was induced in the canal space to the level of the cementoenamel junction in 12 teeth. PRP was prepared and placed in the canals to the level of the cementoenamel junction in 9 teeth. The coronal access was sealed with mineral trioxide aggregate. Seven canines were not operated on and served as controls. Three months later, block sections including each canine and its surrounding tissues were removed for histologic evaluation. The tissues found in the canals of experimental teeth were compared with those in the control teeth.
  
  
  RESULTS
  Almost all of the experimental teeth showed the presence of intracanal bonelike tissue. No evidence of dentinal wall thickening or apical narrowing was noted in the experimental teeth.
  
  
  CONCLUSIONS
  In this experimental model, the use of either PRP or blood clots during regenerative endodontics leads to the formation of intracanal bonelike tissue without continual root maturation.
authors.affiliation: Loma Linda University, Loma Linda, California. Electronic address: mtorabinejad@llu.edu.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Torabinejad
authors.affiliation: Loma Linda University, Loma Linda, California.
authors.forename: Hadi
authors.initials: H
authors.lastname: Faras
authors.affiliation: Loma Linda University, Loma Linda, California.
authors.forename: Robert
authors.initials: R
authors.lastname: Corr
authors.affiliation: Loma Linda University, Loma Linda, California.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Wright
authors.affiliation: Loma Linda University, Loma Linda, California.
authors.forename: Shahrokh
authors.initials: S
authors.lastname: Shabahang
mesh_terms: D017607:Aluminum Compounds / Q000627:therapeutic use; D000818:Animals; D001777:Blood Coagulation / Q000502:physiology*; D017610:Calcium Compounds / Q000627:therapeutic use; D003481:Cuspid / Q000033:anatomy & histology* / Q000502:physiology; D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000098:blood supply / Q000502:physiology; D003809:Dentin, Secondary / Q000033:anatomy & histology / Q000502:physiology; D004338:Drug Combinations; D004492:Edetic Acid / Q000627:therapeutic use; D005289:Ferrets; D005347:Fibroblasts / Q000502:physiology; D008214:Lymphocytes / Q000502:physiology; D008264:Macrophages / Q000502:physiology; D008297:Male; D023421:Models, Animal; D009805:Odontogenesis / Q000502:physiology; D010006:Osteoblasts / Q000502:physiology; D010010:Osteoclasts / Q000502:physiology; D010087:Oxides / Q000627:therapeutic use; D053657:Platelet-Rich Plasma / Q000502:physiology*; D011670:Pulpectomy / Q000379:methods; D011897:Random Allocation; D012038:Regeneration / Q000502:physiology; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012388:Root Canal Irrigants / Q000627:therapeutic use; D017640:Silicates / Q000627:therapeutic use; D013997:Time Factors; D054457:Tissue Scaffolds
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D017640:Silicates; C086631:mineral trioxide aggregate; D004492:Edetic Acid
keywords: Bone; cementum; dentin; ferret; regeneration; revascularization