Secondary closure of small- to medium-size palatal defects after ablative surgery: reappraisal of reconstructive techniques.

PURPOSE: Postoncologic reconstruction of the palate represents a major surgical challenge with respect to the thin intraoral and intranasal lining. Current reconstructive methods have ranged from obturative closure of the defect to microsurgical free tissue transfer. The final choice of treatment will be influenced by the size and location of the defect and surgeon experience. The goals of palate repair include optimizing palatal function for speech and eating, and avoiding dehiscence or postoperative fistulas. This study assessed the reliability of locoregional flaps for reconstructing maxillary defects. PATIENTS AND METHODS: The present study described the surgical outcome of locoregional reconstruction of the hard and soft palate of 5 patients who had previously undergone tumor ablative surgery. They ranged in age from 19 to 64 years. None had received postoperative radiotherapy. The resultant surgical defects ranged in size from 2.5 to 12 cm(2). One patient experienced velopharyngeal insufficiency. RESULTS: In all cases, the palate was closed at the first attempt without complications. All flaps survived, and complete closure was obtained in these 4 patients. The patient with the velopharyngeal insufficiency experienced a significant improvement in articulation and swallowing function. CONCLUSIONS: The results of these 5 cases indicate that secondary locoregional flaps are a suitable alternative for palatal defect management. They have a high success rate and functional outcome. These secondary techniques can be reliably used to reconstruct small- to moderate-size palatal defects and represent a reliable reconstructive option with minimal morbidity.

The effect of platelet-rich plasma in vitro on primary cells: rat osteoblast-like cells and human endothelial cells.

The aim of this study was to evaluate the effects of standardized platelet-rich plasma (PRP) concentrates from 10 human donors on cellular behavior. The standardized PRPs used were fivefold average and fivefold maximum baseline values in whole blood. Both these standardized PRPs were characterized by determining platelet numbers and subsequently growth factor concentrations in activated PRPs, called PRP derivatives. Platelet numbers in both types of standardized PRPs were significantly increased compared with whole blood. Further, both PRP derivatives contained significantly higher concentrations of platelet-derived growth factor-AA, platelet-derived growth factor-AB, and transforming growth factor-beta 1. Vascular endothelial growth factor concentrations were significantly elevated in only the most concentrated PRP derivative. Cell culture experiments with osteoblast-like cells showed that both PRP derivatives stimulated cell proliferation without inducing cell differentiation, whereas tube formation in endothelial cell cultures was significantly increased by adding low volume percentages of PRP derivative (2%–8%). Consequently, it can be concluded that there is no direct relationship between the number of platelets and the level of growth factors released from these platelets. PRP derivatives have the potency to stimulate angiogenesis dose dependently, while lacking the capacity to induce osteogenic differentiation. Yet, the proliferation of osteoblast-like cells can significantly be enhanced by supplementation of PRP derivatives.