OBJECTIVETo establish a miniature pig model of mandibular osteoradionecrosis (ORN).

METHODSA single dose of irradiation (IR25 Gy, 28 Gy) was delivered via an electronic linear accelerator to the right mandible of 24 miniature pigs by utilizing three dimensional conformal radiotherapy (3D-CRT). The first molar of the mandible was extracted 2 months after radiation. Mandibular ORN was diagnosed through gross observation, X-ray film, CT, and histopathologic examination.

RESULTSAt 3-4 months after radiation, all animals suffered from mandibular ORN after dental extraction. The symptoms of ORN were more severe in the 28 Gy group than in the 25 Gy group.

CONCLUSIONA miniature pig model of mandibular ORN can be established through 25 Gy irradiation + dental extraction.

Animals ; Mandible ; Mandibular Diseases ; pathology ; Molar ; Osteoradionecrosis ; pathology ; Particle Accelerators ; Radiation Injuries, Experimental ; pathology ; Radiotherapy, Conformal ; adverse effects ; Swine ; Swine, Miniature ; Tooth Extraction

OBJECTIVETo investigate the effect of Eucommiol on osteogenic differentiation of adipose-derived stem cells (ADSCs), and the feasibility of applying in mandibular defects repair using ADSCs combined with the extract of Eucommiol scaffold material.

METHODSForty-eight New Zealand rabbits were randomly divided into four groups and bilateral mandibular defect was prepared. Group A: Implanted the ADSCs combined with the extract of Eucommiol scaffold, group B: Implanted the ADSCs combined with hydroxyapatite materials, group C: Implanted hydroxyapatite materials, group D: The control group. All the experimental animals were sacrificed after 2, 4, 8, 12 weeks. Tissue samples were observed by gross observation, radiographic analysis, hematoxylin-eosin (HE) staining, scanning electron microscope (SEM). The value of imaging analysis and osteogenesis were evaluated. The results were analyzed by SPSS 17.0 statistical software.

RESULTSIn vivo imaging and histological staining showed that the healing of bone defect and bone quality in group A was significantly better than those in the other groups. SEM showed well biocompatibility between composite material and tissue without inflammation reaction. By measuring and analyzing the dental CT data and new bone area, the bone in group A was obviously better than those in other groups (P < 0.05).

CONCLUSIONThe extract of Eucommiol can promote ADSCs into bone cells. The role of ADSCs combined with extract of Eucommiol scaffold materials has significant bone induction. It is expected that this material could become a new composite material and be used to fix the jaw bone defects.

Adipocytes ; Alcohols ; Animals ; Bone and Bones ; Cell Differentiation ; Cells, Cultured ; Cyclopentanes ; Durapatite ; Mandible ; Osteogenesis ; Rabbits ; Stem Cells ; Tissue Engineering ; Tissue Scaffolds

OBJECTIVETo investigate the treatment effect of mandibular osteoradionecrosis (ORN) by autologous bone marrow mesenchymal stem cells (BMMSC) in miniature pigs.

METHODSSix miniature pigs with mandibular ORN (25 Gy) were used. BMMSC were separated and cultured in vitro and then implanted on to the premolded hydroxyapatite-tricalcium phosphate (HA-TCP). The BMMSC-HA-TCP complexes were implanted into the defective area of mandibular ORN in 4 animals. Implantation of only HA-TCP in 2 animals served as control. Gross observation, spiral CT, coronary CT and histopathologic examination were carried out.

RESULTSFistula disappeared in animals with BMMSC-HA-TCP complexes 3 months after implantation, while fistula was found in controls. Spiral CT analysis showed that cortical bone repair were found 4 months after BMMSC-HA-TCP complexes implantation, while bone damage (cortical and cancellous bone fracture) increased in controls. Histopathologic examination revealed that 4 months later after BMMSC-HA-TCP complexes implantation, new bone formation and bone cells could be observed, but there was a large number of fibrous tissue and no new bone in controls.

CONCLUSIONSTransplantation of autologous BMMSC with HA-TCP may have therapeutic effect in the treatment of mandibular ORN.

Animals ; Bone Marrow Cells ; Calcium Phosphates ; therapeutic use ; Durapatite ; therapeutic use ; Mandibular Diseases ; therapy ; Mesenchymal Stem Cell Transplantation ; Osteoradionecrosis ; therapy ; Swine ; Swine, Miniature ; Transplantation, Autologous