title: Computer-aided design/computer-aided manufacturing of hydroxyapatite scaffolds for bone reconstruction in jawbone atrophy: a systematic review and case report.
abstract: BACKGROUND
  We reviewed the biological and mechanical properties of porous hydroxyapatite (HA) compared to other synthetic materials. Computer-aided design/computer-aided manufacturing (CAD/CAM) was also evaluated to estimate its efficacy with clinical and radiological assessments.
  
  
  METHODS
  A systematic search of the electronic literature database of the National Library of Medicine (PubMed-MEDLINE) was performed for articles published in English between January 1985 and September 2013. The inclusion criteria were (1) histological evaluation of the biocompatibility and osteoconductivity of porous HA in vivo and in vitro, (2) evaluation of the mechanical properties of HA in relation to its porosity, (3) comparison of the biological and mechanical properties between several biomaterials, and (4) clinical and radiological evaluation of the precision of CAD/CAM techniques.
  
  
  RESULTS
  HA had excellent osteoconductivity and biocompatibility in vitro and in vivo compared to other biomaterials. HA grafts are suitable for milling and finishing, depending on the design. In computed tomography, porous HA is a more resorbable and more osteoconductive material than dense HA; however, its strength decreases exponentially with an increase in porosity.
  
  
  CONCLUSIONS
  Mechanical tests showed that HA scaffolds with pore diameters ranging from 400 to 1200 μm had compressive moduli and strength within the range of the human craniofacial trabecular bone. In conclusion, using CAD/CAM techniques for preparing HA scaffolds may increase graft stability and reduce surgical operating time.
authors.affiliation: Biomedical Surgical and Dental Sciences Department, Maxillo-Facial and Odontostomatology Unit, Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico, University of Milan, Milan, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: Garagiola
authors.affiliation: Biomedical Surgical and Dental Sciences Department, Maxillo-Facial and Odontostomatology Unit, Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico, University of Milan, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Grigolato
authors.affiliation: Biomedical Surgical and Dental Sciences Department, Maxillo-Facial and Odontostomatology Unit, Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico, University of Milan, Milan, Italy.
authors.forename: Rossano
authors.initials: R
authors.lastname: Soldo
authors.affiliation: Private Practice, Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Bacchini
authors.affiliation: Biomedical Surgical and Dental Sciences Department, Maxillo-Facial and Odontostomatology Unit, Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico, University of Milan, Milan, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Bassi
authors.affiliation: Biomedical Surgical and Dental Sciences Department, Maxillo-Facial and Odontostomatology Unit, Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico, University of Milan, Milan, Italy.
authors.forename: Rachele
authors.initials: R
authors.lastname: Roncucci
authors.affiliation: Private Practice, Milan, Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: De Nardi
keywords: Computer-aided design/computer-aided manufacturing; Hydroxyapatite; Review; Scaffold