The prefabricated scapula flap consists of syngeneic bone, connective tissue, and a self-assembled epithelial coating

Reconstruction of the maxilla with prefabricated scapular flaps in noma patients

BACKGROUND

Noma (cancrum oris) is a devastating gangrenous disease that leads to severe tissue destruction in the face and is associated with a high rate of mortality. When untreated, it results in disfiguring midface defects and severe scarring. Ideal reconstruction of complex maxillofacial defects requires the restitution of bone, dental implants, soft tissue, and the thin and durable lining of the oral and paranasal cavities. Prefabricated composite grafts from the scapula are used to restore the maxilla in patients with this disease.

METHODS

A new concept of osteosynthesis involving titanium plates connected to dental implants, achieving greater mechanical stability of the reconstructed bony framework, is described. Nine complex midface defects were reconstructed with dermis-prelaminated scapular flaps. A bone flap from the lateral margin of the scapula was taken and osseointegrated implants were inserted. The bone flap was then prelaminated with dermis and covered with a Gore-Tex sheath to prevent adhesion. Two to 3 months later, the composite flap was transferred to the midface.

RESULTS

Restoration of a maxilla with pneumatized paranasal cavities and a keratinized attached epithelium covering the alveolus and hard palate was successfully performed in all noma patients. The reconstructed "masticatory gingiva" and osseointegrated dental implants enabled patients to exercise oral functions shortly after surgery.

CONCLUSION

Long-term observation of selected noma patients showed restoration of oral function and stability of the maxilla after several years.

Effects of subepithelial fibroblasts on epithelial differentiation in human skin and oral mucosa: heterotypically recombined organotypic culture model

The stratified squamous epithelia differ regionally in their patterns of morphogenesis and differentiation. Although some reports suggested that the adult epithelial phenotype is an intrinsic property of the epithelium, there is increasing evidence that subepithelial connective tissue can modify the phenotypic expression of the epithelium. The aim of this study was to elucidate whether the differentiation of cutaneous and oral epithelia is influenced by underlying mesenchymal tissues. Three normal skin samples and three normal buccal mucosa samples were used for the experiments. Skin equivalents were constructed in four ways, depending on the combinations of keratinocytes (cutaneous or mucosal keratinocytes) and fibroblasts (dermal or mucosal fibroblasts), and the effects of subepithelial fibroblasts on the differentiation of oral and cutaneous keratinocytes were studied with histological examinations and immunohistochemical analyses with anti-cytokeratin (keratins 10 and 13) antibodies. For each experiment, three paired skin equivalents were constructed by using single parent keratinocyte and fibroblast sources for each group; consequently, nine (3 x 3) organotypic cultures per group were constructed and studied. The oral and cutaneous epithelial cells maintained their intrinsic keratin expression. The keratin expression patterns in oral and cutaneous epithelia of skin equivalents were generally similar to their original patterns but were partly modified exogenously by the topologically different fibroblasts. The mucosal keratinocytes were more differentiated and expressed keratin 10 when cocultured with dermal fibroblasts, and the expression patterns of keratin 13 in cutaneous keratinocytes cocultured with mucosal fibroblasts were different from those in keratinocytes cocultured with cutaneous fibroblasts. The results suggested that the epithelial phenotype and keratin expression could be extrinsically modified by mesenchymal fibroblasts. In epithelial differentiation, however, the intrinsic control by epithelial cells may still be stronger than extrinsic regulation by mesenchymal fibroblasts.