title: Efficacy and safety of porous hydroxyapatite/type 1 collagen composite implantation for bone regeneration: A randomized controlled study.
abstract: BACKGROUND
  Porous hydroxyapatite/collagen composite (HAp/Col) is a bioresorbable bone substitute composed of nano-scale HAp and porcine type 1 collagen. In this study, the efficacy and safety were assessed in comparison to commercially available porous β-tricalcium phosphate (β-TCP).
  
  
  METHODS
  Patients with bone defects caused by benign bone tumors, fractures, or harvesting of autografts were randomly allocated for implantation of porous HAp/Col (n = 63) or porous β-TCP (n = 63). X-ray images were scored and used to evaluate the efficacy of the implantation until 24 weeks after surgery. Blood tests and observation of the surgical site were also performed to evaluate the safety of the implants. In total, 59 and 60 cases were analyzed in the porous HAp/Col and β-TCP groups, respectively.
  
  
  RESULTS
  At 18 and 24 weeks after surgery, the highest grade of bone regeneration was more frequent in the porous HAp/Col group than in the porous β-TCP group (p = 0.0004 and 0.0254 respectively). Wilcoxon's rank sum test confirmed the superiority of porous HAp/Col from early time points onward (p = 0.0084, 4 w; p = 0.0037, 8 w; p = 0.0030, 12 w; p < 0.0001, 18 w; and p = 0.0316, 24 w). The incidence of adverse effects was higher in the porous HAp/Col group than in the β-TCP group. However, no serious adverse events were reported and no cases needed to drop out of the clinical trial.
  
  
  CONCLUSIONS
  The superiority of porous HAp/Col for bone regeneration in comparison to an established porous β-TCP was confirmed. Although the incidence of side effects associated with the porous HAp/Col implant was higher than that in the β-TCP group, no serious adverse events occurred that resulted in rejection of the implants.
authors.affiliation: Department of Orthopaedic Research and Development, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, Japan; Department of Orthopaedic and Spinal Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima Bunkyo-ku, Tokyo, Japan. Electronic address: sotome.orth@tmd.ac.jp.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sotome
authors.affiliation: Department of Orthopaedic and Spinal Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima Bunkyo-ku, Tokyo, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ae
authors.affiliation: Department of Orthopaedic and Spinal Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima Bunkyo-ku, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Okawa
authors.affiliation: Department of Orthopaedic Surgery, Tsuchiura Kyodo General Hospital, 11-4 Manabeshinmachi, Tsuchiura-shi, Ibaraki, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ishizuki
authors.affiliation: Department of Orthopaedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Morioka
authors.affiliation: Department of Orthopaedic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Kouto-ku, Tokyo, Japan.
authors.forename: Seiichi
authors.initials: S
authors.lastname: Matsumoto
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawaramachi, Sakyo-ku, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Orthopaedic Surgery, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Abe
authors.affiliation: Orthopedic Surgery Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Beppu
authors.affiliation: Department of Orthopaedic and Spinal Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima Bunkyo-ku, Tokyo, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Shinomiya
mesh_terms: D000328:Adult; D001847:Bone Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D001861:Bone Regeneration / Q000502:physiology*; D018786:Bone Substitutes; D002130:Calcium Phosphates / Q000494:pharmacology*; D024042:Collagen Type I / Q000494:pharmacology*; D017886:Durapatite / Q000494:pharmacology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D019736:Prostheses and Implants; D019919:Prosthesis Implantation / Q000379:methods*; D018709:Statistics, Nonparametric; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D024042:Collagen Type I; C485817:beta-tricalcium phosphate; D017886:Durapatite