title: Bone response to free form-fabricated hydroxyapatite and zirconia scaffolds: a histological study in the human maxilla.
abstract: OBJECTIVE
  Synthetic and biological materials are increasingly used to provide temporary or permanent scaffolds for bone regeneration. This study evaluated the effect of material chemistry and microporosity on bone ingrowth and osseointegration of zirconia (ZrO(2)) and hydroxyapatite (HA) scaffolds in the human maxilla.
  
  
  METHODS
  Twelve patients subjected to dental implant placement were enrolled in the study. Scaffolds of ZrO(2) and HA were placed in the maxilla of each subject, using a randomization protocol. After 3 months of healing, biopsies were harvested comprising the scaffolds and surrounding bone tissue. The biopsies were processed for histological evaluation and morphometric analysis (bone ingrowth and bone-to-scaffold contact).
  
  
  RESULTS
  Healing was uneventful in all cases. All scaffolds demonstrated a measurable bone response using light microscopy and scanning electron microscopy. Microporous HA scaffolds revealed four times larger bone ingrowth and seven times larger bone contact as compared with ZrO(2) scaffolds.
  
  
  CONCLUSIONS
  The results show that chemistry and microporosity of HA promote bone ingrowth and bone contact of ceramic scaffolds in human maxilla.
authors.affiliation: Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy, Göteborg University, Gothenburg, Sweden. johan.malmstrom@biomaterials.gu.se
authors.forename: Johan
authors.initials: J
authors.lastname: Malmström
authors.forename: Christer
authors.initials: C
authors.lastname: Slotte
authors.forename: Erik
authors.initials: E
authors.lastname: Adolfsson
authors.forename: Ola
authors.initials: O
authors.lastname: Norderyd
authors.forename: Peter
authors.initials: P
authors.lastname: Thomsen
mesh_terms: D000328:Adult; D000368:Aged; D000539:Alveolar Process / Q000187:drug effects / Q000502:physiology / Q000601:surgery* / Q000648:ultrastructure; D001672:Biocompatible Materials / Q000737:chemistry / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects / Q000502:physiology; D018786:Bone Substitutes / Q000737:chemistry / Q000627:therapeutic use; D017076:Computer-Aided Design; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D048091:Guided Tissue Regeneration / Q000379:methods*; D006801:Humans; D006882:Hydroxyapatites / Q000737:chemistry / Q000627:therapeutic use; D008437:Maxilla; D008875:Middle Aged; D016348:Osseointegration / Q000502:physiology; D016062:Porosity; D018709:Statistics, Nonparametric; D054457:Tissue Scaffolds / Q000737:chemistry*; D055815:Young Adult; D015040:Zirconium / Q000737:chemistry / Q000627:therapeutic use
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D015921:Dental Implants; D006882:Hydroxyapatites; D015040:Zirconium; C028541:zirconium oxide