title: Success rate and strength of osseointegration of immediately loaded UV-photofunctionalized implants in a rat model.
abstract: BACKGROUND
  Despite its clinical benefits, the immediate loading protocol might have a higher risk of implant failure than the regular protocol. Ultraviolet (UV) photofunctionalization is a novel surface enhancement technique for dental implants. However, the effect of photofunctionalization under loading conditions is unclear.
  
  
  OBJECTIVE
  The purpose of this animal study was to evaluate the effect of photofunctionalization on the biomechanical quality and strength of osseointegration under loaded conditions in a rat model.
  
  
  METHODS
  Untreated and photofunctionalized, acid-etched titanium implants were placed into rat femurs. The implants were immediately loaded with 0.46 N of constant lateral force. The implant positions were evaluated after 2 weeks of healing. The strength of osseointegration was evaluated by measuring the bone-implant interfacial breakdown point during biomechanical push-in testing.
  
  
  RESULTS
  Photofunctionalization induced hydrophilic surfaces on the implants. Osseointegration was successful in 28.6% of untreated implants and 100% of photofunctionalized implants. The strength of osseointegration in successful implants was 2.4 times higher in photofunctionalized implants than in untreated implants. The degree of tilt of untreated implants toward the origin of force was twice that of photofunctionalized implants.
  
  
  CONCLUSIONS
  Within the limit of an animal model, photofunctionalization significantly increased the success of osseointegration and prevented implant tilt. Even for the implants that underwent successful osseointegration, the strength of osseointegration was significantly higher for photofunctionalized implants than for untreated implants. Further experiments are warranted to determine the effectiveness of photofunctionalization on immediately loaded dental implants.
authors.affiliation: Research Assistant, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif; and Resident, Advanced Specialty Education Program in Prosthodontics, Loma Linda University, School of Dentistry, Loma Linda, Calif.
authors.forename: Pooya
authors.initials: P
authors.lastname: Soltanzadeh
authors.affiliation: Research Assistant, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif; and Resident, Periodontics Department, Saint Louis University, Center for Advanced Dental Education, St Louis, Mo.
authors.forename: Amirreza
authors.initials: A
authors.lastname: Ghassemi
authors.affiliation: Visiting Assistant Project Scientist, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif. Electronic address: mishijima@ucla.edu.
authors.forename: Manabu
authors.initials: M
authors.lastname: Ishijima
authors.affiliation: Visiting scholar, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Visiting scholar, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif.
authors.forename: Wonhee
authors.initials: W
authors.lastname: Park
authors.affiliation: Visiting scholar, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif.
authors.forename: Chika
authors.initials: C
authors.lastname: Iwasaki
authors.affiliation: Visiting scholar, Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, Calif.
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirota
authors.affiliation: Professor, Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, UCLA School of Dentistry, Los Angeles, Calif.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ogawa
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D015921:Dental Implants; D008297:Male; D023421:Models, Animal; D016348:Osseointegration / Q000502:physiology* / Q000528:radiation effects*; D017207:Rats, Sprague-Dawley; D013499:Surface Properties; D014467:Ultraviolet Therapy / Q000379:methods*; D016474:Weight-Bearing
chemical_list: D015921:Dental Implants