Description of the periodontal pocket in preclinical models: limitations and considerations.

Establishment of periodontal health and regeneration of the lost periodontal tissues are always the ultimate goal of periodontal treatment. The development of new therapeutic approaches raises the necessity for appropriate experimental models that present periodontal structures and healing capability comparable to humans. Preclinical research and extrapolation of the data to human conditions remains a stage of great importance before the clinical application of the new biomaterials and techniques. Periodontal pockets/defects in preclinical models can be induced experimentally through acute or chronic or a combination of both (induced) modalities. The features of the created defects and those of humans vary greatly mostly due to the nature of the periodontal disease. This is an important point to take into account, since it is well recognized that the potential of periodontal therapy may be dependent on both the biological background and the defect morphology. This review provides insight into the commonly used preclinical models for the reproduction of the periodontal pocket and discusses the advantages and disadvantages of each model in terms of similarity to human conditions, standardization and reproducibility.