title: Promotive effect of insulin-like growth factor-1 for epithelial sealing to titanium implants.
abstract: Improvement of oral epithelial adhesion to titanium (Ti) may significantly enhance the efficacy of dental implants. Here, we investigated whether insulin-like growth factor-1 (IGF-1) improved the sealing of the peri-implant epithelium (PIE) around the implant. Right maxillary first molars were extracted from rats and replaced with experimental implants. After 4 weeks of IGF-1 treatment, the implant-PIE interface exhibited a band of immunoreactive laminin-332 (Ln-5), similar to the tooth-junctional epithelium interface, that was partially absent in the untreated group. Immunoelectron microscopy showed a characteristic Ln-5-positive band including hemidesmosomes at both the apical and upper portions of the implant-PIE interface in the IGF-1-treated group. We also investigated the effects of IGF-1/PI3K inhibitors on the dynamics of rat oral epithelial cells (OECs) grown on Ti plates. In OECs cultured with IGF-1, adhesion protein expression increased, cell adherence to Ti plates was higher, and proliferation was faster, whereas migration and apoptosis were induced in the absence of IGF-1 or in the presence of both IGF-1 and a PI3K inhibitor. These data suggest that PI3K mediates the promotive effects of IGF-1, and that IGF-1 is effective at enhancing epithelial integration around Ti implants.
authors.affiliation: Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan; Center for Craniofacial Molecular Biology, University of Southern California School of Dentistry, Los Angeles, California.
authors.forename: Ikiru
authors.initials: I
authors.lastname: Atsuta
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Ayukawa
authors.forename: Akihiro
authors.initials: A
authors.lastname: Furuhashi
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Yamaza
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Tsukiyama
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Koyano
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D004848:Epithelium / Q000187:drug effects*; D020007:Implants, Experimental; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D039663:Integrin beta4 / Q000378:metabolism; D007797:Laminin / Q000494:pharmacology; D009061:Mouth Mucosa / Q000187:drug effects; D051190:Plectin / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects; D014014:Tissue Adhesives / Q000494:pharmacology*; D014025:Titanium / Q000494:pharmacology*
chemical_list: D015815:Cell Adhesion Molecules; D039663:Integrin beta4; D007797:Laminin; D051190:Plectin; D014014:Tissue Adhesives; D007334:Insulin-Like Growth Factor I; D014025:Titanium
keywords: adhesion molecule; dental implant; epithelial cell; growth factor; titanium