Elham Hassan

The present study aimed to evaluate osteogenic potential and biocompatibility of combining biphasic calcium phosphate with zirconia nanoparticles (4Zr TCP/HA) compared to biphasic calcium phosphate (TCP/HA) for reconstruction of induced mandibular defects in dog model. TCP/HA and 4Zr TCP/HA scaffolds were prepared. Morphological, physicochemical, antibacterial, cytocompatibility characterization were tested. In vivo application was performed in 12 dogs where three critical-sized mandibular defects were created in each dog. Bone defects were randomly allocated into: control, TCP/HA, and 4Zr TCP/HA groups. Bone density and bone area percentage were evaluated at 12 weeks using cone-beam computed tomographic, histopathologic, histomorphometric examination. Bone area density was statistically increased (p < 0.001) in TCP/HA and 4Zr TCP/HA groups compared to control group both in sagittal and coronal views. Comparing TCP/HA and 4Zr TCP/HA groups, the increase in bone area density was statistically significant in coronal view (p = 0.002) and sagittal view (p = 0.05). Histopathologic sections of TCP/HA group demonstrated incomplete filling of the defect with osteoid tissue. Doping with zirconia (4Zr TCP/HA group), resulted in statistically significant increase (p < 0.001) in bone formation (as indicated by bone area percentage) and maturation (as confirmed by Masson trichrome staining) compared to TCP/HA group. The newly formed bone was mature and organized with more trabecular thickness and less trabecular space in between. Physicochemical, morphological and bactericidal properties of combining zirconia and TCP/HA were improved. Combining zirconia and TCP/HA resulted in synergistic action with effective osteoinduction, osteoconduction and osteointegration suggesting its suitability to restore damaged bone in clinical practice.

There is a lack of reports describing ultrasonographic and histopathologic features of ocular diseases in donkeys. The present study aimed to document ultrasonographic and histopathologic changes associated with common ocular diseases in donkeys. The study included 45 donkeys (64 eyes) with ocular diseases that had reached the end of their working lives and requested to be used for educational and research purposes. Complete clinical, ophthalmic, ultrasonographic, gross pathologic and histopathologic examinations were included. Ocular abnormalities were documented, tabulated, and analyzed. Seventy-five ocular abnormalities were diagnosed with multiple involvements within the same eye including anterior uveitis (n = 13; 22.8%), cataract (n = 57; 76%), retinal detachment (n = 3; 4%), lens and phthisis bulbi (n = 2; 2.6%). Descriptive ultrasonographic findings of ocular abnormalities were included. Gross pathologic and histopathology findings confirmed the ultrasonography findings. Ultrasonography provided a clinically useful tool offering insight into detailed intraocular structures especially with opacification of the dioptric structures of the eye.

OBJECTIVE: To evaluate bioactivity and osteogenic potential of calcium silicate (CS)-doped iron oxide (FeO) nanoparticles versus pure CS in the reconstruction of induced critical-sized mandibular defects.

DESIGN: CS-doped FeO was prepared; morphological and microstructure identification of nanoparticles were made. An randomised design was developed on 24 adult male dogs where four critical-sized mandibular defects were created in each dog. Bone defects were allocated into control, CS, CS-3% FeO and CS-10% FeO group. Dogs were euthanized at 1 and 3 months (12 dog/time) for histopathologic and histomorphometric evaluation.

RESULTS: At three months, bone formation and maturation were evident where mean ± SD percent of mature bone was 2.66 ± 1.8, 9.9 ± 2.5, 22.9 ± 4.9, and 38.6 ± 8.1 in control, CS, CS-3% FeO, and CS-10% FeO groups respectively. A high significant ( < 0.001) increase in area percent of mature bone was recorded in CS, CS-3% FeO, and CS- 10% FeO groups compared to control group (73%, 88% and 93.3% respectively). Significant increase ( < 0.001) in area of mature bone was recorded in CS-3% FeO and CS-10% FeO groups compared to CS group. A significant increase ( < 0.001) in area of mature bone formation was detected in CS-10% FeO group compared to other groups.

CONCLUSION: CS-doped FeO has good osteoconductive, biocompatible properties with promoted bone regeneration. FeO has synergistic effect in combination with CS to promote bone formation. Increasing concentration of FeO nanoparticles resulted in improved osteogenesis and maturation. Results suggests that the novel CS-FeO alloplasts could be used for reconstruction of critical-sized bone defects.