This study aimed to evaluate and compare the effects of bone grafting materials, including xenograft alone, DBC alone, xenograft + DBC, xenograft + boric acid, and xenograft + boric acid-absorbed DBC, on the newly formed bone, the immune reactivity score of osteoprotegerin (OPG) and Receptor Activator Nuclear Kappa-B Ligand (RANKL) and the OPG/RANKL ratio by histological, histomorphometric and immunohistochemical analysis in rabbit maxillary sinus augmentation (MSA) model. Fourteen maxillary sinuses of New Zealand albino rabbits were augmented. Five groups were formed: xenograft alone (group1), dispersed bacterial cellulose (DBC) alone (group2), xenograft + DBC (group3), xenograft + boric acid (group4), xenograft +boric acid-absorbed DBC (group5). Eight weeks later, the species were examined. SEM, XRD, and FTIR analyses were carried out for DBC and boric acid-absorbed DBC. Inter-group comparisons were carried out by using the Kruskal-Wallis test for the immune reactivity score of OPG and RANKL and the independent sample t-test for OPG/RANKL ratio. The highest newly formed bone was observed in groups 3 and 5, and the lowest was in group 1. The percentages of newly formed bone area from highest to lowest occurred at 43.3 %, 38.3 %, 33.3 %, 30 %, and 19.5 % in groups 5, 3, 4, 2, and 1, respectively. Increased expression of OPG and RANKL was observed around newly formed bone areas in all groups. The immune reactivity score of OPG and RANKL expression was highest in group 5 and lowest in group 1, with no significant difference between the groups. The OPG/RANKL ratio was 1 in all groups, except the ratio was > 1 in only group 5, with no significant difference between the groups. The surface of DBC showed a well-organized, irregular, and interconnected porous structure. DBC found a biocompatible material. Boric acid-absorbed DBC produced a more remarkable and enlarged pore structure than DBC alone. The findings of the present pilot study indicated that DBC alone can be used as a scaffold and it seems an innovative bone graft material to filling bone defect areas that it caused enhanced bone regeneration during MSA. Moreover, adding DBC or boric acid-absorbed DBC to xenograft increased newly formed bone significantly.