title: The mechanical integrity of in vivo engineered heterotopic bone.
abstract: Recent advances in tissue engineering have aroused interest in growth of heterotopic bone for the repair of skeletal defects. This study demonstrates an in vivo method in minipigs of engineering individual human-sized mandible replacements of heterotopic bone with a mechanical integrity similar to natural bone. Ten individualized mandible replacement scaffolds were created using computer-aided design (CAD) techniques. Five had a resorbable external scaffold made of polylactite mesh (test group 1) and five had had a non-resorbable external scaffold of titanium mesh (test group 2). The mesh scaffolds were loaded each with five BioOss blocks serving as internal scaffolds and 3.5 mg recombinant human Bone Morphogenetic Protein-7. The loaded mesh scaffolds were implanted into the latissimus dorsi muscles of five infant minipigs. After 6 weeks the mandible replacements were harvested. Core biopsy cylinders were taken from the replacements of both test groups and from the natural pig mandibles (control 1). Also, core biopsies from plain BioOss Blocks were gained (control 2). The core biopsy cylinders were loaded axially into a compression test device to evaluate the mechanical compression resistance. Additional specimen underwent histological examination. Both test groups resulted in successful bone induction with degrees of compression resistance [Test 1: 1.62 MPa (SD+/-0.73); Test 2: 1.51 MPa (SD+/-0.56)] statistically insignificant when compared to natural porcine mandibular bone [1.75 MPa (SD+/-0.69)]. This differed significantly from the much lower compression resistance seen in the unadulterated BioOss [0.92 MPa (SD+/-0.04)]. Following this, the in vivo engineered bone has a similar mechanical compression stability as natural bone.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Kiel, Arnold-Heller-Str. 16, 24 105 Kiel, Germany. warnke@mkg.uni-kiel.de
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Warnke
authors.forename: Ingo N
authors.initials: IN
authors.lastname: Springer
authors.forename: Yahya
authors.initials: Y
authors.lastname: Acil
authors.forename: Gerrit
authors.initials: G
authors.lastname: Julga
authors.forename: Jörg
authors.initials: J
authors.lastname: Wiltfang
authors.forename: Klaus
authors.initials: K
authors.lastname: Ludwig
authors.forename: Paul A J
authors.initials: PA
authors.lastname: Russo
authors.forename: Eugene
authors.initials: E
authors.lastname: Sherry
authors.forename: Sureshan
authors.initials: S
authors.lastname: Sivananthan
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hedderich
authors.forename: Hendrik
authors.initials: H
authors.lastname: Terheyden
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry*; D018786:Bone Substitutes / Q000737:chemistry*; D019245:Compressive Strength; D004548:Elasticity; D019544:Equipment Failure Analysis; D048091:Guided Tissue Regeneration / Q000379:methods*; D020007:Implants, Experimental; D008334:Mandible / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D008422:Materials Testing; D019563:Mechanics; D013314:Stress, Mechanical; D013552:Swine; D013556:Swine, Miniature; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes