Mechanism of pro-apoptotic action of prosthetic restorations on oral mucosa cells.

PURPOSE: The aim of this study was to check the pro-apoptotic mechanism of prosthetic reconstruction on epithelial cells of the oral mucosa. PATIENTS AND METHODS: The research was carried out on the saliva of healthy patients using prostheses. The sample swabs were stained using the May-Grünwald-Giemsa method and processed by immunohistochemistry for nuclear factor kappa B (NF-κB; p65) and caspase-3. Western blots were used to detect caspase-3, NF-κB, p53 and COX-2 expression. RESULTS: We found an increased expression of caspase-3, NF-κB and p53 in the oral epithelial cells of patients using prosthetic restorations compared to the subjects from the control group. No differences in COX-2 expression were found between the groups. The strongest immunoreactivity and expression of caspase-3, NF-κB and p53 were observed in patients using full prosthesis for less than two years. CONCLUSIONS: The results of the conducted research indicate that prosthetic restorations may affect the process of apoptosis of oral mucosa epithelial cells. Lack of difference in expression of COX-2 in the saliva of the studied patients suggests that apoptosis is not caused by inflammatory factors.

Fractal texture analysis of the healing process after bone loss.

Radiological assessment of treatment effectiveness of guided bone regeneration (GBR) method in postresectal and postcystal bone loss cases, observed for one year. Group of 25 patients (17 females and 8 males) who underwent root resection with cystectomy were evaluated. The following combination therapy of intraosseous deficits was used, consisting of bone augmentation with xenogenic material together with covering regenerative membranes and tight wound closure. The bone regeneration process was estimated, comparing the images taken on the day of the surgery and 12 months later, by means of Kodak RVG 6100 digital radiography set. The interpretation of the radiovisiographic image depends on the evaluation ability of the eye looking at it, which leaves a large margin of uncertainty. So, several texture analysis techniques were developed and used sequentially on the radiographic image. For each method, the results were the mean from the 25 images. These methods compute the fractal dimension (D), each one having its own theoretic basis. We used five techniques for calculating fractal dimension: power spectral density method, triangular prism surface area method, blanket method, intensity difference scaling method and variogram analysis. Our study showed a decrease of fractal dimension during the healing process after bone loss. We also found evidence that various methods of calculating fractal dimension give different results. During the healing process after bone loss, the surfaces of radiographic images became smooth. The result obtained show that our findings may be of great importance for diagnostic purpose.