Carrageenin-Induced Periodontitis as an Experimental Model in Rats Analyzed by Micro-Computerized Tomography

Periodontitis is a common disease worldwide and is a cause of tooth loss. For these reasons, many investigators have examined periodontitis not only by in vivo studies but also in vitro studies. For in vivo studies, it is very important which animal is used and how to make experimental periodontitis easily and efficiently in animals. Although the process of periodontitis in monkeys and dogs is similar to that in humans, rats and mice are much more useful animals for experiments because of ease of handling and low cost. For the induction of periodontitis, bacterial inoculation and wire ligature methods were examined previously; however, these methods had temporal and technical problems. Therefore, a simple, easy and reliable experimental model for periodontitis using rats and/or mice is required. In this study, the authors attempted to establish a novel experimental model for periodontitis in the rat lower jaw using carrageenin-immersed silk ligature wire, and examined the change of alveolar bone morphology by micro-computerized tomography. As a result, carrageeninimmersed silk ligature wire induced inflammation of the periodontium with severe alveolar bone loss in all experimental rats. In addition, the degree of absorption of the alveolar bone depended on the dosage times of carrageenin treatment. These findings suggested that this experimental model of periodontitis using carrageenin in rats may be a useful experimental model for periodontal research.