title: Effect of UV Photofunctionalization on Osseointegration in Aged Rats.
abstract: OBJECTIVE
  This study evaluated the effect of photofunctionalization on osseointegration under the biologically adverse conditions of aging.
  
  
  METHODS
  First of all, bone marrow-derived osteoblastic cells from young (8 weeks old) and aged (15 months old) rats were biologically characterized. Then, the osteoblasts from aged rats were seeded on titanium discs with and without photofunctionalization, and assessed for initial cell attachment and osteoblastic functions. Titanium mini-implants, with and without photofunctionalization, were placed in the femur of aged rats, and the strength of osseointegration was measured at week 2 of healing. Periimplant tissue was examined morphologically and chemically using scanning electron microscopy and energy dispersive x-ray spectroscopy, respectively.
  
  
  RESULTS
  Cells from the aged rats showed substantially reduced biological capabilities compared with those derived from young rats. The cells from aged rats showed significantly increased cell attachment and the expression of osteoblastic function on photofunctionalized titanium than on untreated titanium. In addition, the strength of osseointegration was increased by 40% in aged rats carrying the photofunctionalized implants. Robust bone formation was observed around the photofunctionalized implants with strong elemental peaks of calcium and phosphorus, whereas the tissue around untreated implants showed weaker calcium and phosphate signals than titanium ones.
  
  
  CONCLUSIONS
  These in vivo and in vitro results corroboratively demonstrate that photofunctionalization is effective for enhancing osseointegration in aged rats.
authors: *Visiting Scholar, Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA; Research Assistant, Department of Partial Denture Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan. †Visiting Scholar, Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA. ‡Associate Professor, Department of Partial Denture Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan. §Professor, Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, CA.
authors: Manabu
authors: M
authors: Ishijima
authors: Amirreza
authors: A
authors: Ghassemi
authors: Pooya
authors: P
authors: Soltanzadeh
authors: Miyuki
authors: M
authors: Tanaka
authors: Kourosh
authors: K
authors: Nakhaei
authors: Wonhee
authors: W
authors: Park
authors: Makoto
authors: M
authors: Hirota
authors: Naoki
authors: N
authors: Tsukimura
authors: Takahiro
authors: T
authors: Ogawa
mesh_terms: D000367:Age Factors; D000818:Animals; D000069343:Bone-Implant Interface / Q000528:radiation effects; D015921:Dental Implants; D005269:Femur / Q000601:surgery; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D008855:Microscopy, Electron, Scanning; D016348:Osseointegration / Q000528:radiation effects*; D010006:Osteoblasts / Q000528:radiation effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013052:Spectrometry, X-Ray Emission; D014025:Titanium; D014467:Ultraviolet Therapy / Q000379:methods*
chemical_list: D015921:Dental Implants; D014025:Titanium