Periodontitis is a chronic infectious inflammation of microbial origin that results in the destruction of periodontal tissues: the gingiva, cementum, periodontal ligament, and alveolar bone. The goal of successful periodontal therapy is to create a new attachment by the regeneration of lost tissue.1 Regeneration becomes well evidenced by improved clinical, including reduction in PD and BOP, and gain in CAL.2 Regenerative procedures are found to have more pronounced clinical, radiological, and histological improvements than the traditional modalities of treatments showing deeper regeneration of cementum, periodontal ligaments, and bone.
Tissue engineering represents one of the important approaches in periodontal regeneration. The three key elements in the practice of tissue engineering are cell selection, biomaterial scaffolds, and bioactive signals, including growth factors.3 The scaffold material is required to be biocompatible and support the proliferation, differentiation, and tissue regeneration process. While bone grafts still represent the gold standard of scaffold materials, they present disadvantages including limited availability, immunogenic risks, and donor site morbidity. Autografts need supplementary surgical sites and, as a result, create problems at the donor site, whereas allografts, like Freeze-Dried Bone Allograft (FDBA), can elicit immunological reactions or even transmit pathogens.4 Xenograft forms questionable bone quality and is therefore associated with reduced primary stability after the placement of implants.5
The collagen chitosan hydrogels have been developed to meet these limitations as possible alternatives to bone grafts. These hydrogels combine the osteogenic properties of collagen and the stability of chitosan through hydrogen bonding 6 into a three-dimensional porous scaffold that allows cell migration and nutrition transport.7 In addition, hydrogels act as drug delivery carriers, allowing the sustained release of bioactive molecules. Despite their benefits, hydrogels require reinforcing agents like chitosan to enhance their mechanical properties and to slow down degradation rates.