Discussion
bone loss, tooth
ADHESION, BONE LOSS
This study used CBCT scanning and histological examination to evaluate degradation and new bone formation associated with the use of rhBMP-2/BioCaP/β-TCP and β-TCP as filling materials in socket preservation. CBCT scanning showed that there was a greater GV decrease in the rhBMP 2/BioCaP/β-TCP group than in the β-TCP group, which suggest a faster degradation rate of this material. In addition, less residual material and more new bone formation were identified in rhBMP-2/BioCaP/β-TCP group based on histomorphometric examination.In both CBCT and biopsy tissue samples, the center of the filled area was selected to assess bone density, the volume of residual material, and new bone, as there were fewer interference factors (soft tissue and old bone tissue) around the target sites. Since the biopsies were 6 mm high, 3 mm under the reference of the alveolar ridge and alongside the tooth-long axis was included for GV change measurement, and CBCT results revealed that rhBMP-2/BioCaP/β-TCP group has more GV decrease in CBCT images, which indicated faster degradation than β-TCP group, and this assumption was confirmed in histomorphometric evaluations. Despite the CBCT results were consistent with those from histomorphometric assays. GV from CBCT alone cannot precisely reflect bone density, as GV quantifies the amount of X-ray attenuation of bone tissue and filled materials. Therefore, CBCT cannot independently determine the occurrence of new bone development.The faster degradation of rhBMP-2/BioCaP/β-TCP may be attributed to more cell adhesion. In biomaterial-induced bone regeneration, biomaterials act as scaffolds where bone cells and osteoclasts can adhere and grow [Multislice computed tomography (MSCT) and micro-CT have been widely used to evaluate bone density, using the Hounsfield unit (HU) values, in orthopedics and laboratory studies [Alveolar ridge preservation can provide adequate alveolar bone for dental implants [In this study, patients with extraction defect assessment (EDS) class 1 (EDS-1) or 2 (EDS-2), having less bone loss than those with EDS-3 or EDS-4, were included after tooth extraction, and they were in a better condition for bone healing. The rhBMP-2/BioCaP/β-TCP group was superior to β-TCP and natural healing (control) groups in bone formation. However, to assess the efficiency of rhBMP-2/BioCaP/β-TCP in adverse conditions for bone regeneration (e.g., EDS-3 and EDS-4), more studies are warranted.