'Medical University Prof. Dr. Paraskev Stoyanov - Varna'
Doi
Abstract
Introduction: Periodontitis is a highly prevalent chronic inflammatory disease characterized by a progressive loss of gingival tissue, the periodontal ligament and adjacent supporting alveolar bone leading to early tooth loss.The purpose of this review was to summarize the literature data on rat periodontitis models.Materials and Methods: Literature was accessed through PubMed and Scopus. Articles, including reviews and animal studies, were analyzed to establish the currently used rat models of periodontal disease.Results: The literature shows that the rat is the most extensively studied rodent for the pathogenesis of periodontal disease because periodontal anatomy in the molar region shares some similarities with that of humans. Under natural conditions, the rat appears to be extremely resistant to periodontal diseases. Nevertheless, periodontitis can be experimentally induced. There are 4 types of models according to the causative factor: bacteria or bacterial products, diet, ligature, and surgery. The inoculation of bacteria (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans or Fusobacterium nucleatum) may cause periodontitis. Periodontal inflammation can also be induced by a single intragingival injection of lipopolysaccharides from bacteria such as Aggregatibacter actinomycetemcomitans and Salmonella typhimurium. The dietary models are induced by feeding the animals a carbohydrate-rich high-calorie diet. In the ligature-induced model, a plaque retentive silk or cotton ligature is fixed in the gingival sulcus around the molar teeth. A surgical model in rats has been proposed in the last 10 years. This model consists of surgically creating a periodontal defect in the form of fenestrations on the radicular surfaces of the second mandibular molars.Conclusion: Experimental periodontitis models in animals are a very important tool for the investigation of the disease pathogenesis and the possible new therapies
