title: Interactions of liposomes with dental restorative materials.
abstract: The in vitro adsorption and retention of liposomes onto four common types of dental restorative materials (conventional and silorane-based resin composites as well as conventional and resin-modified glass ionomer cements (GIC)) have been investigated due to their potential use in the oral cavity. Uncoated liposomes (positively and negatively charged) and pectin (low- and high-methoxylated) coated liposomes were prepared and characterized in terms of particle size and zeta potential. The adsorption of liposomes was performed by immersion, quantified by fluorescence detection, and visualized by fluorescence imaging and atomic force microscopy. Positive liposomes demonstrated the highest adsorption on all four types of materials likely due to their attractive surface charge. They also retained well (minimum 40% after 60 min) on both conventional resin composite and GIC even when exposed to simulated salivary flow. Although an intermediate initial level of adsorption was found for the pectin coated liposomes, at least 70% high methoxylated-pectin coated liposomes still remained on the conventional resin composite after 60 min flow exposure. This indicates significant contribution of hydrophobic interactions in the prolonged binding of liposomes to resin composites. Based on these results, the present paper suggests two new possible applications of liposomes in the preservation of dental restorations.
authors.affiliation: Nordic Institute of Dental Materials (NIOM), Sognsveien 70A, NO-0855 Oslo, Norway. Electronic address: s.h.nguyen@farmasi.uio.no.
authors.forename: Sanko
authors.initials: S
authors.lastname: Nguyen
authors.affiliation: Department of Pharmacy, School of Pharmacy, University of Oslo, Sem Sælands vei 3, NO-0371 Oslo, Norway. Electronic address: m.i.adamczak@farmasi.uio.no.
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Adamczak
authors.affiliation: Department of Pharmacy, School of Pharmacy, University of Oslo, Sem Sælands vei 3, NO-0371 Oslo, Norway. Electronic address: marianne.hiorth@farmasi.uio.no.
authors.forename: Marianne
authors.initials: M
authors.lastname: Hiorth
authors.affiliation: Department of Pharmacy, School of Pharmacy, University of Oslo, Sem Sælands vei 3, NO-0371 Oslo, Norway. Electronic address: gro.smistad@farmasi.uio.no.
authors.forename: Gro
authors.initials: G
authors.lastname: Smistad
authors.affiliation: Nordic Institute of Dental Materials (NIOM), Sognsveien 70A, NO-0855 Oslo, Norway. Electronic address: h.b.m.kopperud@niom.no.
authors.forename: Hilde Molvig
authors.initials: HM
authors.lastname: Kopperud
mesh_terms: D000327:Adsorption; D003764:Dental Materials; D003793:Dental Restoration, Permanent; D008081:Liposomes; D018625:Microscopy, Atomic Force
chemical_list: D003764:Dental Materials; D008081:Liposomes
keywords: Adsorption; Dental restorative materials; Glass ionomer cements; Liposomes; Resin composites; Retention