Histomorphometric Evaluation of Bone-Guided Regeneration in Maxillary Sinus Floor Augmentation Using Nano-Hydroxyapatite/Beta-Tricalcium Phosphate Composite Biomaterial: A Case Report.

Background The development of techniques in biomaterials design and production added to advanced surgical procedures which enabled better and more predictable clinical outcomes. Maxillary sinus floor augmentation (MSFA) is among the more studied bone-guided regeneration procedure in the literature. The MSFA could be considered the gold standard procedure for bone-guided regeneration as it provides suitable functional and aesthetic solutions to alveolar ridge atrophy due to tooth loss. Purpose This study aimed to conduct a detailed histomorphometric evaluation of collagen production in SFAs bone-guided regeneration, using nano-hydroxyapatite/s-tricalcium phosphate (nano-HA/s-TCP) composite. Patients and Methods A 52-year-old female had the left upper second premolar condemned due to periodontal disease, then a tooth implant replacement was planned. Due to maxillary sinus pneumatization, the MSFA had to be done before implant placement. Nano-HA/s-TCP composite (2g) was used in the MSFA procedure. After nine months of the healing process, during the Cone Morse implant installation process, bone samples were collected for histologic analysis (sirius red, hematoxylin/eosin, polarized microscopy). Six months after implant installation, a ceramic crown was installed according to the patient's request. Results Proper masticatory function and aesthetics were re-established. The histomorphometric evaluation indicated that nano-HA/s-TCP composite did not show any area devoid of cellular activity in sirius red or hematoxylin/eosin staining and the percentage (%) of new bone collagen fibers was achieved using polarization technique evaluation. Conclusion According to these results, nano-HA/s-TCP composite presented clinical and histomorphometric properties suit to be used as bone-guided regeneration biomaterial in MSFA. Furthermore, nano-HA/β-TCP composite provided a favorable nano-environment to bone cells, enhancing bone matrix production.