Histologic characterization of engineered tissues in the canal space of closed-apex teeth with apical periodontitis.
BACKGROUND
The aim of this study was to investigate the capacity of endodontic regenerative procedures combining an induced blood clot, platelet-rich plasma (PRP), and bone marrow aspirate (BMA) to regenerate dental pulp in canine closed-apex necrotic teeth.


METHODS
Apical periodontitis was induced in 20 upper and lower premolars of 2 dogs. After biomechanical preparation, enlargement to a #60 file, and disinfection with a triantibiotic paste for 28 days, the roots were randomly assigned to 4 treatment groups: blood clot (BC), BC + PRP gel, BC + BMA gel, and BC + BMA/PRP gel. Negative controls were also included. After a 3-month follow-up period, the animals were killed.


RESULTS
Histologic analysis showed the presence of newly formed vital tissues (connective, cement-like, and bone-like tissue) in 23 of the 32 treated roots (71.87%). There was no statistically significant difference between the treatment groups.


CONCLUSIONS
New vital tissues were formed and characterized as connective, cementum-like, or bone-like, but not as pulp-like tissue; PRP and/or BMA did not improve the tissue ingrowth.
Department of Endodontics, Araçatuba School of Dentistry, Universidade Estadual Paulista, Araçatuba, São Paulo, Brazil. Electronic address: jegomesfilho@yahoo.com.br.
João Eduardo
JE
Gomes-Filho
Paulo Carvalho Tobias
PC
Duarte
Edilson
E
Ervolino
Suely Regina
SR
Mogami Bomfim
Caio José
CJ
Xavier Abimussi
Ludmilla
L
Mota da Silva Santos
Carolina Simonetti
CS
Lodi
Sandra Helena
SH
Penha De Oliveira
Elói
E
Dezan
Luciano Tavares Angelo
LT
Cintra
D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001641:Bicuspid / Q000473:pathology; D001777:Blood Coagulation / Q000502:physiology; D001854:Bone Marrow Cells / Q000502:physiology; D001842:Bone and Bones / Q000473:pathology; D002939:Ciprofloxacin / Q000627:therapeutic use; D003238:Connective Tissue / Q000473:pathology; D003739:Dental Cementum / Q000473:pathology; D003786:Dental Pulp Cavity / Q000473:pathology*; D003789:Dental Pulp Exposure / Q000628:therapy; D003790:Dental Pulp Necrosis / Q000628:therapy; D004285:Dogs; D004338:Drug Combinations; D005347:Fibroblasts / Q000473:pathology; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use; D008911:Minocycline / Q000627:therapeutic use; D018919:Neovascularization, Physiologic / Q000502:physiology; D010485:Periapical Periodontitis / Q000628:therapy*; D053657:Platelet-Rich Plasma / Q000502:physiology; D011897:Random Allocation; D012038:Regeneration / Q000502:physiology; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000379:methods; D013917:Thrombin / Q000627:therapeutic use; D023822:Tissue Engineering / Q000379:methods*
D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D012388:Root Canal Irrigants; D008795:Metronidazole; D002939:Ciprofloxacin; D013917:Thrombin; D008911:Minocycline
Bone marrow aspirate; necrotic teeth; platelet-rich plasma; regenerative endodontics; tissue engineering; vital tissue growth