title: Formation of a mandibular condyle in vitro by tissue engineering.
abstract: OBJECTIVE
  Mandibular reconstructive procedures often produce significant donor site morbidity. Recently, the use of minimally invasive techniques has been reported for mandibular reconstruction with decreased morbidity at the primary operative site. To date, these techniques have not addressed the graft donor site. We hypothesize that tissue-engineering techniques may be used to fabricate bone and thereby eliminate donor site morbidity.
  
  
  METHODS
  Porcine mesenchymal stem cells (pMSCs) were isolated from the bone marrow of 3 Yucatan minipigs and grown in standard culture flasks. When they became near-confluent, cells were detached and replated with the addition of osteogenic supplements. A model of a porcine mandibular condyle was made and used to fabricate porous polymer scaffolds from biodegradable poly DL-lactic-co-glycolic acid (PLGA). Differentiated osteoblasts were transferred to the PLGA scaffold and cultured for 6 weeks in a rotational oxygen-permeable bioreactor system. The cultured constructs, consisting of scaffold and cells, were evaluated by gross, radiologic, and histologic examinations.
  
  
  RESULTS
  The engineered constructs were white and hard and had a shape that closely resembled that of the model condyle. Plain radiographs demonstrated that the radiodensity of the construct was between that of the normal condyle and that of control scaffolds. Histologically, bone was observed on the entire surface of the PLGA scaffolds with an average thickness of 0.03 mm. Bone was not observed in the control scaffolds.
  
  
  CONCLUSIONS
  In this pilot study, autologous tissue-engineered bone constructs were successfully made by combining biodegradable polymers and pMSCs.
authors.affiliation: Department of Oral and Maxillofacial Surgery-Massachusetts General Hospital and Harvard School of Dental Medicine, Boston, MA 02114, USA.
authors.forename: Harutsugi
authors.initials: H
authors.lastname: Abukawa
authors.forename: Hidetomi
authors.initials: H
authors.lastname: Terai
authors.forename: Didier
authors.initials: D
authors.lastname: Hannouche
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Vacanti
authors.forename: Leonard B
authors.initials: LB
authors.lastname: Kaban
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Troulis
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D015519:Bone Density; D001857:Bone Matrix / Q000473:pathology; D002113:Calcification, Physiologic; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002455:Cell Division; D003094:Collagen / Q000737:chemistry; D004396:Coloring Agents; D005260:Female; D019344:Lactic Acid / Q000737:chemistry; D008335:Mandibular Condyle / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000473:pathology; D008648:Mesoderm / Q000502:physiology; D010006:Osteoblasts / Q000502:physiology; D010011:Osteocytes / Q000473:pathology; D010012:Osteogenesis; D010865:Pilot Projects; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry; D011859:Radiography; D016622:Silver Staining; D013234:Stem Cells / Q000502:physiology; D013552:Swine; D013556:Swine, Miniature; D023822:Tissue Engineering / Q000295:instrumentation / Q000379:methods
chemical_list: D001672:Biocompatible Materials; D004396:Coloring Agents; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D003094:Collagen; D000469:Alkaline Phosphatase