title: Release of titanium ions from an implant surface and their effect on cytokine production related to alveolar bone resorption.
abstract: Although interest in peri-implant mucositis and peri-implantitis has recently been increasing, the mechanisms driving these diseases remain unknown. Here, the effects of titanium ions on the inflammation and bone resorption around an implant were investigated. First, the accumulated amount of Ti ions released into gingival and bone tissues from an implant exposed to sodium fluoride solution was measured using inductively coupled plasma mass spectrometry. Next, the cellular responses in gingival and bone tissues to Ti ions and/or Porphyromonas gingivalis-lipopolysaccharide (P. gingivalis-LPS) were assessed using a rat model. More Ti ions were detected in the gingival tissues around an implant after treatment with sodium fluoride (pH 4.2) than in its absence, which suggests that the fluoride corroded the implant surface under salivary buffering capacity. The injection of Ti ions (9ppm) significantly increased the mRNA expression and protein accumulation of chemokine (C-C motif) ligand 2, as well as the ratio of receptor activator of nuclear factor-κB ligand to osteoprotegerin, in rat gingival tissues exposed to P. gingivalis-LPS in a synergistic manner. In addition, the enhanced localization of toll-like receptor 4, which is an LPS receptor, was observed in gingival epithelium loaded with Ti ions (9ppm). These data suggest that Ti ions may be partly responsible for the infiltration of monocytes and osteoclast differentiation by increasing the sensitivity of gingival epithelial cells to microorganisms in the oral cavity. Therefore, Ti ions may be involved in the deteriorating effects of peri-implant mucositis, which can develop into peri-implantitis accompanied by alveolar bone resorption.
authors.affiliation: Section of Fixed Prosthodontics, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Wachi
authors.affiliation: Section of Fixed Prosthodontics, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shuto
authors.affiliation: Section of Fixed Prosthodontics, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Shinohara
authors.affiliation: Section of Fixed Prosthodontics, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Matono
authors.affiliation: Section of Fixed Prosthodontics, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Electronic address: makihira@dent.kyushu-u.ac.jp.
authors.forename: Seicho
authors.initials: S
authors.lastname: Makihira
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001862:Bone Resorption; D017077:Culture Media, Conditioned; D016207:Cytokines / Q000096:biosynthesis*; D017931:DNA Primers; D004797:Enzyme-Linked Immunosorbent Assay; D008070:Lipopolysaccharides / Q000494:pharmacology; D008334:Mandible / Q000473:pathology*; D051379:Mice; D008969:Molecular Sequence Data; D016966:Porphyromonas gingivalis / Q000378:metabolism; D019736:Prostheses and Implants; D011506:Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014025:Titanium / Q000378:metabolism*
chemical_list: D017077:Culture Media, Conditioned; D016207:Cytokines; D017931:DNA Primers; D008070:Lipopolysaccharides; D011506:Proteins; D012333:RNA, Messenger; D014025:Titanium
keywords: OPG; Peri-implantitis; RANKL; Titanium ion