The application of the investigated three-dimensional collagen matrix in vestibuloplasty achieved a sufficient amount of peri-implant attached gingiva in head and neck cancer patients. The favorable tissue reaction and the low shrinking tendency make the collagen matrix a promising alternative to autologous tissue grafts.
In this report, we present a case of a prelaminated radial forearm flap in reconstruction of a large persistent cleft palate with transoral single arterial and three venous anastomoses. A 17-years-old female patient presented a large cleft palate defect and complete dentition, dysmelia of both arms and bilateral thumb aplasia. A radial flap was prelaminated using oral mucosa 5 days prior to transplantation. Five days after flap prelamination, the facial artery and vein, submandibular vein, and a venous branch to the masseter muscle behind the buccinator muscle fibers were exposed through an intraoral incision lateral to the inferior right mucogingival junction. The radial artery, its bilateral accompanying veins, and the cephalic vein of transplanted flap were anastomosed transorally to the facial vessels, submandibular vein, and masseter branch. The vessel pedicle ran through the palatoglossal arch dorsal to the second upper molar. Good flow and flap perfusion were evinced, and further-on successful healing was achieved. The case encourages similar treatment in comparable situations avoiding facial nerve hazard and extraoral scars.
Classically skin defects are covered by split thickness skin grafts or by means of local or regional skin flaps. In the presented case series for the first time a bilayered, non-crossed-linked collagen matrix has been used in an off-label fashion in order to reconstruct facial skin defects following different types of skin cancer resection. The material is of porcine origin and consists of a spongy and a compact layer. The ratio of the two layers is 1:3 in favour of the spongy layer. The aim of the study was to investigate the potential of this matrix for skin regeneration as an alternative to the standard techniques of skin grafts or flaps. Six patients between 39 and 83 years old were included in the study based on a therapeutic trial. The collagen matrix was used in seven defects involving the nose, eyelid, forehead- and posterior scalp regions, and ranging from 1,2 to 6 cm in diameter. Two different head and neck surgeons at two different institutions performed the operations. Each used a different technique in covering the wound following surgery, i.e. with and without a latex-based sheet under the pressure dressing. In three cases cylindrical biopsies were taken after 14 days. In all cases the biomaterial application was performed without any complication and no adverse effects were observed. Clinically, the collagen matrix contributed to a tension-free skin regeneration, independent of the wound dressing used. The newly regenerated skin showed strong similarity to the adjacent normal tissue both in quality and colour. Histological analysis indicated that the spongy layer replaced the defective connective tissue, by providing stepwise integration into the surrounding implantation bed, while the compact layer was infiltrated by mononuclear cells and contributed to its epithelialization by means of a „conductive“process from the surrounding epithelial cells. The clinical and histological data demonstrate that the collagen bilayered matrix used in this series contributes to a „Guided-Integrative-Regeneration-Process“, which still needs to be further understood. The biomimetic nature of this material seems to contribute to physiological matrix remodelling, which probably involves other matricellular proteins essential for soft tissue regeneration. A deeper understanding of the mechanism, involved in the tissue integration of this material and its contribution to soft tissue regeneration based on the direct and indirect effect of matricellular proteins could open new therapeutic avenues for biomaterial-based soft tissue regeneration as an alternative to traditional flap-based plastic surgery.
Injection of endothelial progenitor cells (EPCs) into arteries for cell therapy is a promising field in regenerative medicine. However, adhesion of EPCs during capillary passage is restricted, and non-adhering cells are lost into circulation. Here we demonstrate that it is possible to achieve a three- to sevenfold higher rate of EPC adhesion to endothelium and extracellular matrix molecules after short-term activation with phorbol myristate acetate (PMA). In addition, differentiation and toxicity analyses of PMA activated EPCs showed no impact on cell differentiation and negligible impact on cell survival.
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