ラット下顎切歯抜歯窩の治癒過程に関する研究

Abstract

Prosthodontic treatment is difficult if the alveolar ridge is low or thin. To develop a method for alveolar ridge preservation after tooth extraction, we need an experimental model of a small animal, in which we can analyze the socket healing easily and quantitatively. The purpose of the present study was to establish such an experimental model. Ten weeks old male rats of Wistar strain were used. The edge of the right mandibular incisor was cut every three days three times and the incisor was extracted at three days after the final cut. The animals were sacrificed 0, 1, 2, 4, 8, 12 weeks after the extraction and the mandibles were dissected out. The length of the alveolar bone was measured on soft X-ray photographs and bone mineral content was measured with a dual energy X-ray absorptiometer (DEXA). Then, transverse sections of the alveolar bone were prepared. Periodic three-times cutting of the edge of the mandibular incisor made the extraction easy. Quantitative analyses of new bone formation in the socket and the resorption of the alveolar bone were possible with soft X-ray photography and DEXA. The histological findings corresponded well with the data from the soft X-ray photos and DEXA measurements. The present results demonstrated the possibility of simple and quantitative analyses of socket healing after the extraction of rat mandibular incisors. This experimental model would be useful for developing a method to prevent atrophy of the alveolar ridge after tooth extraction.