The organotypic raft culture model has been shown to be a useful method for examining the effects of biochemical manipulation on various epithelial cell types, using in vitro conditions that simulate the in vivo environment of the tissue of origin. To investigate this method as a model for photodynamic therapy (PDT), we cultures the oral squamous carcinoma cell line YD-10B on fibroblast-containing collagen gels at the air-liquid interface and assessed the efficacy of PDT using a photosensitiser 5-ALA-hexenyl ester. PDT effect on YD-10B organotypic raft cultures after twenty- four hours was determined. The number of residual cells was significantly reduced in comparison to control at all four different conditions. PCNA immunostaining and TUNEL assay revealed that PDT inhibited cell proliferation and increased apoptosis. These findings suggest that the organotypic raft culture model provides an effective and rapid laboratory method of investigating strategies for PDT on oral precancerous lesions and squamous cell carcinomas

Primary localized amyloidosis of the palate is a rare condition. We present a case of localized amyloidosis of the palate of a 49-year-old Korean female who suffered from asymptomatic nodular swelling. Microscopic examination revealed extensive deposition of pale eosinophilic amorphous material throught the lamina propria and within the walls of small blood vessels. A diagnosis of localized amyloidosis was made after the biopsy revealed characteristic staining on Congo red, and an extensive workup for systemic involvement was negative. Localized amyloidosis should be considered in the differential diagnosis of palatal nodular lesions