title: Promotion of osseointegration of anodized titanium implants with a 1α,25-dihydroxyvitamin D3 submicron particle coating.
abstract: OBJECTIVE
  A biochemical approach to implant surface modification may offer an alternative to physicochemical and morphologic methods for obtaining desirable bone-implant interfaces. The objective of this study was to investigate the bone tissue response to anodized titanium implant surfaces coated with a poly(D,L-lactide-co-glycolide) (PLGA) solution mixed with 1α,25-diydroxyvitamin D3 (1α,25-(OH)2D3) via an electrospray technique.
  
  
  METHODS
  Threaded implants were manufactured and anodized under 300 V at 660 Hz for 3 minutes (control group). Half of the implants were then coated with 0.15 mL of the PLGA/1α,25-(OH)2D3 solution (5 μg/implant) via electrospray (experimental group). Surface topography was evaluated using field-emission scanning electron microscopy and optical interferometry. Forty-eight implants (12 implants per group per healing period) were surgically placed in random sites in the tibiae of 12 New Zealand white rabbits. After 4 and 12 weeks of healing, undecalcified ground sections were subjected to histologic and histomorphometric analyses.
  
  
  RESULTS
  At week 4, the mean bone-to-implant contact ratio (BIC%) over the entire length of the implant in the experimental group was 37.08% ± 10.18%, versus 28.01% ± 8.70% in the control group. The mean BIC% value in the first four consecutive threads of the experimental group was 48.64% ± 15.92%, compared to 36.11% ±13.49% in the control group (P < .05). At week 12, the mean overall BIC% values were 39.10% ± 7.68% in the experimental group and 29.53% ± 9.49% in the control group. The mean BIC% value in the first four consecutive threads of the experimental group was 51.80% ± 16.41%, versus 37.35% ± 11.77% in the control group (P < .05).
  
  
  CONCLUSIONS
  The current study demonstrated that the PLGA/1α,25-(OH)2D3 solution coating resulted in submicron-sized particles, which may stimulate bone formation adjacent to the surface of implants inserted into bone.
authors.affiliation: Department of Prosthodontics and Dental Research Institute, School of Dentistry, Seoul National University, Korea.
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Cho
authors.forename: Seong-Joo
authors.initials: SJ
authors.lastname: Heo
authors.forename: Jai-Young
authors.initials: JY
authors.lastname: Koak
authors.forename: Seong-Kyun
authors.initials: SK
authors.lastname: Kim
authors.forename: Shin-Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Joo-Hee
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000818:Animals; D002117:Calcitriol / Q000008:administration & dosage / Q000502:physiology*; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D004337:Drug Carriers / Q000008:administration & dosage; D019344:Lactic Acid / Q000008:administration & dosage; D016348:Osseointegration / Q000187:drug effects*; D010316:Particle Size; D011100:Polyglycolic Acid / Q000008:administration & dosage; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011817:Rabbits; D011897:Random Allocation; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013977:Tibia / Q000187:drug effects* / Q000601:surgery / Q000648:ultrastructure; D014025:Titanium / Q000737:chemistry
chemical_list: D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D004337:Drug Carriers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D014025:Titanium; D002117:Calcitriol