Abstract: Objective: To establish an animal model of gingival recession. Methods: We chose rats as the experimental subjects. In this study, we made specified defects close to the mesial surface of rats' maxillary first molars on the right side(treatment group). Then we closed the wounds. After two months, rats were sacrificed, we incised the bilateral maxillary molars and periodontal tissue, then measured the length from the occlusal surface to the mesial gingiva of the first maxillary molar. Results: The results showed that rats' gingiva appeared significant recession two weeks later (P<0.01). Conclusion: Gingival recession is a kind of common disease in clinical practice, this model on rats provides a better animal model compared with those large animals some researchers used before. It saves experimental outlay and spaces in the lab. It is more suitable for large numbers of experimental objects.

Key words: Gingival recession, Animal model on rats , Defects on alveolar bone