Effect of Poly-L-Lysine coating on titanium osseointegration: from characterization to in vivo studies

Abstract

Dental implant prostheses cannot preclude a correct and stable implant osseointegration, which is still a challenge and greatly depends on biomaterial-cell interface. Titanium (Ti) coating using polyelectrolyte poly-L-lysine (PLL) may represent an interesting and simple approach, to provide a charged surface net able to improve cell adherence. However, in vitro and in vivo effects of Ti coated with PLL have been poorly investigated. The aims of the present study are (1) to obtain and characterize, chemically and physically, Ti disks coated with PLL (TiPLL); (2) to perform in vitro studies on osteoblast cell lines' cytocompatibility and functionality (alkaline phosphatase [ALP] activity, calcium deposition, proinflammatory interleukin 6 production); (3) to obtain in vivo evidence of osseointegration, using a sheep animal model. XPS, AFM, and contact-angle analyses demonstrated that the Ti disk was successfully covered with PLL, providing higher hydrophilicity to the Ti disk. No cellular toxicity, enhanced calcium deposition, and a decreased tendency toward interleukin-6 production were observed in the osteoblast seeded onto TiPLL. In vivo experiments showed cortical bone microhardness at 3 months significantly improved in the presence of the PLL coating. PLL coating on Ti implants seemed to safely enhance calcium deposition and implant early osseointegration in animals, suggesting promising evidence to optimize the surface properties of dental implants.

Peptide-Enriched Silk Fibroin Sponge and Trabecular Titanium Composites to Enhance Bone Ingrowth of Prosthetic Implants in an Ovine Model of Bone Gaps

“…The percentage ratio between the linear contact of the newly formed tissue including lamellar bone, woven bone and osteoid within the implants and the total perimeter of the implants was calculated on the same slides used for the stereological analysis in order to quantify the amount of osseointegration using a dedicated navigation software (Image J, NIH; Varoni et al, 2015). A mean value over the 10 photos was then computed and an average tissue to implant contact (TIC) was obtained for each section (Fabbro et al, 2017;Ragone et al, 2020).…”

Double acid etching treatment of dental implants for enhanced biological properties

“…Among the different variables, surface features are one of the most important factors, including physicochemical and topographical properties. Previous studies have shown that the modulation of the surface properties has enhanced the osseointegration of dental implants in the short and long term (4-7). In this sense, many studies suggest that microstructured and nanostructured topographies may better guide cell behavior compared with surface chemistry (8).…”

Biodegradable polymers for dental tissue engineering and regeneration

“…Similarly, Varoni et al studied in vitro and in vivo effects of poly-L-lysine coating on titanium osseointegration. Such coating safely enhanced calcium deposition and implant early osseointegration in animals, suggesting promising evidence to optimize the surface properties of these dental implants [356]. Walters et al investigated the antimicrobial properties of poly(L-lysine) in mono/tricalcium phosphates-HA composites.…”