[Use of experimental animals in caries research]

Animal models have been used extensively in biomedical research. The choice of the most appropriate model for a given research project is fundamental and depends upon specific characteristics of the animal. In the field of Preventive Dentistry the rodent species possess certain advantages which make them extremely useful in caries research and in dental plague pathogenicity. In caries research, rats have been used successfully to study anticaries efficacy of chemical agents, immunization, cariogenicity of diet, maturation of enamel and bacterial involvement in caries process. In this paper the dental characteristics of the rats are discussed emphasizing on the structure of their teeth, oral flora and composition of the saliva. Some of the experimental methods and procedures commonly used for microbial sampling, caries scoring and preparing diet are also described. In addition, an emphasis in given to certain experimental variables, which if not identified and strictly controlled, can attribute to a great variability and inaccuracy of the results. Finally, a basic experimental design for animal caries tests is suggested. In the last few decades, progress in caries research has substantially resulted from the utilization of the animal model system which have enabled examination of various facets of this disease under controlled laboratory conditions. The knowledge gained so far has been successfully applied on man with regard to diagnosis, treatment and prevention on dental caries.