Design, 3D production, mechanical characterization, and investigation of biological activity of nanocrystalline cellulose-reinforced lattice dental grafts

Biocompatible and high-strength grafts are critically important for repairing defects in alveolar bone augmentation and ensuring mechanical integrity. Cellulose, a natural polymer, stands out as a promising reinforcement material in bone tissue engineering applications due to its superior mechanical properties and hydrophilic character. In this study, 3D lattice grafts reinforced with nanocrystalline cellulose purified from date pits were produced by the MSLA method using BCC, FCC, and Kelvin unit cell geometries. As a result of the characterization analyses (FTIR, XRD, TGA/DTA, DSC), it was determined that the obtained cellulose exhibited structural and thermal properties compatible with commercial forms. Mechanical tests showed that as the cellulose content increased, hardness and load-bearing capacity also increased, and the BCC15 graft exhibited the highest compressive strength of approximately 51 MPa and the best thermal stability. The Kelvin15 graft showed the highest Shore D hardness values and the most balanced stress distribution. In the biological analyses, it was observed that the addition of cellulose enhanced the hydrophilic character by increasing surface wettability, and cell attachment was highest in the BCC15 and FCC grafts. In addition, the BCC15 graft was found to exhibit a 48% antibacterial effect against Enterococcus faecalis. As a result, the use of cellulose obtained from date pits in lattice grafts is considered a successful strategy that simultaneously provides the mechanical strength, biocompatibility, and antibacterial protection required for alveolar bone regeneration. Keywords:Alveolar bone augmentation,BCC/FCC/Kelvin geometries,Lattice graft design, Nanocrystalline cellulose.