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Background and purpose: The ultimate goal in periodontal treatment is to achieve a functional and anatomical regeneration of lost tissues. Due to the promising outcomes of biologic modifiers in regenerative therapies, this systematic review aimed at evaluating the effects of various biologic modifiers used in intra-bony osseous defects in animal models.
Materials and methods: Electronic databases were searched for articles published in March 2010-March 2020 that had evaluated the effect of bio-modifiers used in periodontal intra-bony osseous defects in animal models. Screening was performed based on inclusion/exclusion criteria and SYRCLE tool was used for studies’ quality assessment.
Results: After screening the titles, abstracts, and full-texts, 18 studies were included in qualitative analysis and five studies entered the meta-analysis. According to the configuration of osseous defects, the studies were categorized into three subgroups. Based on histological findings, all these biologic markers significantly enhanced new bone and cementum formation compared to control groups (P<0.001). The meta-analysis showed that biologic modifiers could significantly increase bone regeneration
(1.58 mm, 95% CI: 1.12-2.03, P˂0.001) and cementum regeneration (1.27 mm, 95% CI: 0.84-1.70, P˂0.001) in one-wall osseous defects.
Conclusion: Biologic modifiers namely growth factors could positively affect periodontal regeneration, particularly the cementum and bone in animal models. Further human studies are necessary to address the clinical use of these biomaterials.