title: Clinical aspects and strategy for biomaterial engineering of an auricle based on three-dimensional stereolithography.
abstract: At the present time, the partial and/or complete reconstruction of an auricle from autologous rib cartilage is one of most widely published techniques. In the field of tissue engineering, different techniques have been described to generate cartilage tissue using isolated chondrocytes. The basis of these tissue-engineering techniques is bioresorbable or non-bioresorbable biomaterials, which serve as a three-dimensional cell carrier. Tissue engineering of an auricle requires preformed bioresorbable biomaterials designed to fit the form of a patient's auricular defect. Three-dimensional imaging acquired from computed tomography scans or laser surface scanning has become an important tool in modern medicine. This study represents the preoperative procedures for the reconstruction of an auricle through tissue engineering in accordance with the clinical aspects. Hyaff 11, a hyaluronic acid derivative, was used as a three-dimensional cell carrier for isolated human nasoseptal chondrocytes. The chondrocytes were amplified in a conventional monolayer culture before the cells were seeded on a hyaluronic non-woven mesh and cultured in vitro for 4 weeks. The chondrogenic potential of human nasal chondrocytes in Hyaff 11 was investigated by confocal laser scanning microscopy, histology (toluidine blue) and immunohistochemistry (collagen type II). Computer-aided design (CAD) and manufacture of an auricle model with stereolithographical methods were used for the prefabrication of a bioresorbable three-dimensional cell carrier designed in the form of a patient's auricular defect. The cell carrier used was Hyaff 11, a fully benzyl-esterified hyaluronic acid derivative. Confocal laser scanning microscopy has shown good cell attachment, a homogenous distribution of amplified chondrocytes and a viability of more than 90%. After 4 weeks in vitro culture the human nasoseptal chondrocytes synthesized new cartilage with the expression of cartilage-specific collagen type II. In order to shape a patient's designed scaffold the auricle model was fitted exactly and symetrically to the contralateral side. Subsequently, the mirror image patient-specific model was used to prepare an identical scaffold model made of a fully benzyl-esterified hyaluronic acid derivative. The bioresorbable scaffold that was produced gave a satisfactory representation of auricle structure. Bioresorbable preformed biomaterials in the form of a patient's auricle defect represent an important prerequisite for the tissue engineering of autologous auricle grafts. Hyaff 11 seems to be a promising material for tissue engineering of cartilage transplants, and the application of this approach will improve conventional reconstructive surgery in the future.
authors.affiliation: Department of Otorhinolaryngology and Head and Neck Surgery, Ludwig Maximilian University, Marchioninistr. 15, 81377 Munich, Germany. andreas.naumann@hno.med.uni-muenchen.de
authors.forename: A
authors.initials: A
authors.lastname: Naumann
authors.forename: J
authors.initials: J
authors.lastname: Aigner
authors.forename: R
authors.initials: R
authors.lastname: Staudenmaier
authors.forename: M
authors.initials: M
authors.lastname: Seemann
authors.forename: R
authors.initials: R
authors.lastname: Bruening
authors.forename: K H
authors.initials: KH
authors.lastname: Englmeier
authors.forename: G
authors.initials: G
authors.lastname: Kadegge
authors.forename: A
authors.initials: A
authors.lastname: Pavesio
authors.forename: E
authors.initials: E
authors.lastname: Kastenbauer
authors.forename: A
authors.initials: A
authors.lastname: Berghaus
mesh_terms: D020341:Absorbable Implants; D001672:Biocompatible Materials; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology; D017076:Computer-Aided Design; D004431:Ear, External / Q000002:abnormalities / Q000293:injuries / Q000601:surgery; D006801:Humans; D006820:Hyaluronic Acid / Q000031:analogs & derivatives*; D021621:Imaging, Three-Dimensional; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009666:Nose; D011474:Prosthesis Design / Q000379:methods*; D023822:Tissue Engineering / Q000379:methods*; D014057:Tomography, X-Ray Computed
chemical_list: D001672:Biocompatible Materials; C086358:hyaluronic acid benzyl ester; D006820:Hyaluronic Acid