title: Micro-CT and PET analysis of bone regeneration induced by biodegradable scaffolds as carriers for dental pulp stem cells in a rat model of calvarial "critical size" defect: Preliminary data.
abstract: Bone regeneration strategies in dentistry utilize biodegradable scaffolds seeded with stem cells able to induce bone formation. However, data on regeneration capacity of these tissue engineering constructs are still deficient. In this study micro-Computed tomography (micro-CT) and positron emission tomography (PET) analyses were used to investigate bone regeneration induced by two scaffolds [Granular deproteinized bovine bone (GDPB) and Beta-tricalcium phosphate (β-TCP)] used alone or in combination with dental pulp stem cells (DPSC) in a tissue engineered construct implanted in a rat critical calvarial defect. Bone mineral density (BMD) and standard uptake value (SUV) of tracer incorporation were measured after 2, 4, 8, and 12 weeks post-implant. The results showed that: (1) GDPB implants were mostly well positioned, as compared to ß-TCP; (2) GDPB induced higher BMD and SUV values within the cranial defect as compared to ß-TCP, either alone or in combination with stem cells; (3) addition of DPSC to the grafts did not significantly induce an increase in BMD and SUV values as compared to the scaffolds grafted alone, although a small tendency to increase was observed. Thus our study demonstrates that GDPB, when used to fill critical calvarial defects, induces a greater percentage of bone formation as compared to ß-TCP. Moreover, this study shows that addition of DPSC to pre-wetted scaffolds has the potential to ameliorate bone regeneration process, although the set of optimal conditions requires further investigation.
authors.affiliation: Department of Oral and Maxillofacial Sciences, "Sapienza" University of Rome, Rome, Italy.
authors.forename: Susanna
authors.initials: S
authors.lastname: Annibali
authors.forename: Diana
authors.initials: D
authors.lastname: Bellavia
authors.forename: Livia
authors.initials: L
authors.lastname: Ottolenghi
authors.forename: Andrea
authors.initials: A
authors.lastname: Cicconetti
authors.forename: Maria Paola
authors.initials: MP
authors.lastname: Cristalli
authors.forename: Roberta
authors.initials: R
authors.lastname: Quaranta
authors.forename: Andrea
authors.initials: A
authors.lastname: Pilloni
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D015519:Bone Density; D001861:Bone Regeneration; D018786:Bone Substitutes; D002130:Calcium Phosphates; D002417:Cattle; D002454:Cell Differentiation; D002478:Cells, Cultured; D003094:Collagen; D003399:Craniotomy; D003782:Dental Pulp / Q000166:cytology; D020007:Implants, Experimental; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology; D016348:Osseointegration; D010006:Osteoblasts / Q000166:cytology; D049268:Positron-Emission Tomography / Q000379:methods*; D051381:Rats; D011923:Rats, Nude; D012886:Skull / Q000503:physiopathology / Q000601:surgery*; D013552:Swine; D054457:Tissue Scaffolds; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014945:Wound Healing
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate; D003094:Collagen
keywords: [18F]-NaF; biomaterials; bone regeneration; stem cells; μ-CT; μ-PET