Search

Aims To test the immobilization of vascular endothelial growth factor ( VEGF165) on the surface of titanium implants using DNA oligonucleotide ( ODN) anchor strands for the ability to enhance periimplant bone formation. Materials and Methods DNA oligonucleotides were anchored to the surface of sandblasted acid-etched ( SAE) titanium screw implants and were hybridized with complementary strands of ODN conjugated to rh VEGF165. The implants were tested against blank SAE implants and SAE implants with nano-anchored ODN. The implants were inserted into the tibiae of 36 Sprague-Dawley rats. Primary outcome parameters were bone-implant contact ( BIC), amount of new bone formation and periimplant bone density ( BD). density after 1, 4 and 13 weeks. Unit of analysis has been the individual implant. Results Implants with rh VEGF165 hybridized to ODN anchor strands exhibited significantly increased average BIC after 1 month compared to blank implants and implants with anchored ODN strands. Conclusions It is concluded that rh VEGF165immobilized on the surface of titanium implants through nano-anchored oligonucleotide strands can accelerate BIC of sandblasted and etched titanium implants to a certain extent. The radius of effect of the growth factor appears to be limited to tissue immediately adjacent to the implant surface. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to assess the antimicrobial activity and flow of root canal sealers after incorporating novel highly loaded antimicrobial drug-silica coassembled particles (DSPs)., Methods: DSPs were synthesized through coassembly of silica and octenidine dihydrochloride (OCT) antimicrobial surfactant. DSPs were loaded (1% and 2% wt) into epoxy resin sealer (AH Plus [AH]; Dentsply DeTrey GmbH, Konstanz, Germany) or calcium silicate-based sealer (EndoSequence Bioceramic Sealer (BC); Brasseler, Savannah, GA). OCT release from DSP-modified sealers was determined using liquid chromatography. Antimicrobial activity of sealers against planktonic or biofilm form Enterococcus faecalis was assessed using direct contact and membrane restricted tests. Sealer flow was tested according to ISO6876:2012., Results: OCT release from BC + 1% or 2% DSPs was above the minimum inhibitory concentration following 2 days throughout the 30-day experiment, whereas OCT release from AH + 1% or 2% DSP was significantly below the minimum inhibitory concentration against E. faecalis (4 μg/mL) over the whole 30-day experimental period. All materials (with or without DSPs) killed planktonic bacteria initially. AH ± 1% or 2% DSPs had no antimicrobial activity after 7 days. BC + 1% or 2% DSPs maintained antibacterial activity over the 30-day period. Both modified and unmodified sealers completely inhibited the growth of E. faecalis biofilms after 24 hours of contact. DSPs decreased the flow of AH and BC sealers; for AH, the reduction was proportional to the amount of DSPs added. All modified and unmodified sealers, except for AH + 2% DSPs, were within the acceptable limits of ISO 6876 flow tests., Conclusions: DSPs enhanced the antimicrobial performance of BC but not AH, whereas the material's flow remained compliant with ISO 6876 standards. Depending on the sealer, DSPs may enhance antimicrobial efficacy in root canal treatment and potentially improve treatment outcome., (Copyright © 2021 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)