Experimental Animal Models in Periodontology: A Review

In periodontal research, animal studies are complementary to in vitro experiments prior to testing new treatments. Animal models should make possible the validation of hypotheses and prove the safety and efficacy of new regenerating approaches using biomaterials, growth factors or stem cells. A review of the literature was carried out by using electronic databases (PubMed, ISI Web of Science). Numerous animal models in different species such as rats, hamsters, rabbits, ferrets, canines and primates have been used for modeling human periodontal diseases and treatments. However, both the anatomy and physiopathology of animals are different from those of humans, making difficult the evaluation of new therapies. Experimental models have been developed in order to reproduce major periodontal diseases (gingivitis, periodontitis), their pathogenesis and to investigate new surgical techniques. The aim of this review is to define the most pertinent animal models for periodontal research depending on the hypothesis and expected results

The structure of periodontal tissues formed following guided tissue regeneration therapy of intra-bony defects in the monkey

Objective: To describe the periodontal tissues formed following guided tissue regeneration (GTR) therapy of intra-bony defects (IBD). Methods: Eight adult Macaca fascicularis monkeys were used. Proximal IBD were created at the mandibular second pre-molars and second molars. After 3 months, GTR surgery was performed. The animals were euthanized at 6 months and 2 years after surgery. Block biopsies were harvested, and prepared for histological analysis. Results: At 6 months the defect had healed with new cementum (NC), periodontal ligament (PDL) and bone. The NC seemed to be firmly anchored to the dentin. Supracrestally, the NC consisted of a 10 μm thick layer of acellular extrinsic fibre cementum (AEFC). Sub-crestally, the NC was considerably thicker and consisted of an inner layer of AEFC and an outer thicker layer of cellular mixed fibre cementum (CMFC). The extrinsic fibre density amounted to about 10 fibres per 100 μm. The PDL was wider than the pristine PDL and widened in coronal direction. After 2 years of healing, the thickness of the NC in the sub-crestal compartment had increased by about 20 μm and the fibre density had increased by about 50%. Conclusion: After 2 years of healing the structure of the regenerated tissues resembled that of pristine periodontal tissues. © 2006 The Authors.Link_to_subscribed_fulltex