RÉSUMÉ
Objective: To evaluate the feasibility of immature permanent teeth pulp regeneration with a new method that utilizes the integration of concentrated growth factor (CGF) as a scaffold and stromal cell-derived factor-1 (SDF-1). Methods: Canine dental pulp cells (DPC) were isolated and cultured in vitro. Then the effects of SDF-1 and CGF were observed on DPC proliferation and differentiation. The pulpless model was established on the beagle’s immature incisors which were divided into four groups: natural pulp (A), empty cannel (B), CGF-filling (C) and SDF-1/CGF-filling (D). After 10 weeks, specimens were checked by imaging examination, RT-PCR and histological observation. Results: CGF extraction (CGFe) induced DPC proliferation while the combination of SDF-1 and CGFe enhanced this effect and also facilitated odontogenic and angiogenic differentiation of DPC. According to imaging examination, the apex growth of all four groups was in varying degrees. RT-PCR indicated the expressions of odontogenesis and angiogenesis related genes in group D were higher than those in group C. Besides, neonatal dentin and dental-pulp-like tissue were observed inside the canal of both group C and D, while only cementum-like tissue existed around root apex of group B. Conclusion:SDF-1 plays an important role in driving the process of pulp-like-tissue regeneration of immature permanent teeth by using CGF as an effective scaffold.
RÉSUMÉ
PURPOSE: The purpose of this study was to compare the removal torques of a chemically modified SLActive implant and a blasted, laser-treated (BLT) implant, which were soaked in saline for 2 weeks after their surface modifications. The removal torques of the two implants were measured 4 weeks after their implantation into the bone defect area in rabbit tibias with concentrated growth factor (CGF) application. MATERIALS AND METHODS: To make artificial bone defects in the cortical layers of both tibias, an 8-mm diameter trephine bur was used. Then, prepared CGF was applied to the bony defect of the left tibia, and the bony defect of the right tibia was left unfilled. Four weeks later, the surgical sites of 16 rabbits were re-exposed. For 8 rabbits, the SLActive implants (Straumann, Switzerland) were inserted in the left tibia, and the BLT implants (CSM implant, Daegu, Korea) were inserted in the right tibia. For other rabbits, the BLT implants were inserted in the left tibia, and the SLActive implants were inserted in the right. Four weeks afger the insertion, torque removal was measured from 4 rabbits exterminated via CO2 inhalation. RESULTS: No significant difference was observed between removal torques of the BLT implant and the SLActive implant (P>.05). CONCLUSION: It was found that BLT surface modification exhibited excellent osseointegration. In addition, CGF application did not affect the insertion and removal torque of the implants.