Background: Odontogenic neoplasms and cysts have diverse biological behaviors, ranging from indolence to aggression along a spectrum. The proliferating cell nuclear antigen (PCNA) is an antigen involved in DNA synthesis and proliferation. Focal adhesion kinase (FAK) is a cytoplasmic molecule associated with cellular signaling, growth, and invasion. PCNA and FAK markers have been shown to be involved in neoplastic proliferation, invasion, and migration. Hence, an immunohistochemical assay of PCNA and FAK can be used as a predictive tool for the level of aggressive behavior of odontogenic lesions. Methods:The current study was conducted to evaluate the expressions of PCNA and FAK. A double immunohistochemical technique for conventional ameloblastoma (AB), unicystic AB, calcifying epithelial odontogenic tumor (CEOT), and glandular odontogenic cyst (GOC) was used to evaluate the role of both markers in assessments of the aggressiveness of selected odontogenic lesions. All formalin-fixed paraffin-embedded blocks (n = 10) for each studied group were double PCNA and FAK immunostained and then assessed using a transmission light microscope and an image-analyzer computer system. Statistical analysis was performed with a one-way analysis of variance (ANOVA) test followed by Tukey's post hoc test.Results: All study groups showed nuclear immunoreactivity of PCNA and cytoplasmic immunoreactivity for FAK. The greatest mean nuclear count of PCNA and the greatest mean area percent for FAK were both recorded in the aggressive lesions; i.e., the CEOT group and conventional AB group. The non-aggressive unicystic AB group had a lower mean nuclear count for PCNA and showed the lowest mean area percent for FAK. Conclusions:In conclusion, PCNA and FAK immunoexpression profiles may have a strong correlation with the aggressive nature of AB, CEOT, and GOC. Hence, PCNA and FAK markers could aid in their routine examination, treatment planning, and prognosis.

Objectives: This study aimed to investigate the effects of denosumab application on calvarial bony defects of rabbits through histological, and radiological methods. Material & Methods:In our current experimental study 30 healthy adult New Zealand male Rabbits were used in evaluation of the healing capacity of densoumab on calvarial bone defect. We assigned animals randomly with ratio (1:1) to either study group receiving the examined drug or the control group that received no treatments. Animals in the Study group received denosumab injection after carrying out surgery to create osseous defects while in control group animals did not receive any drug postoperatively. At 2, 6, and 12 weeks postoperatively, five animals from each group were euthanized. All groups were examined radiographically for bone density, histologically for the type and progression of the healing process, the characteristics of the developed connective tissue, the nature of the formed osteoid matrix, inflammatory process associated nature. Results:The radiographic examination as well as the histological examination showed a significant difference between the Study group (denosumab group) & the control group in bone healing capacity. The (denosumab group) showed formation of new thin woven bone bridges 2 weeks postoperatively that became thicker at 6 weeks then at 12 weeks both groups showed signs of healing but the Study group (denosumab group) had more lamellar well organized bone with new haversian systems with wide osteons. Conclusion:The results demonstrate that Denosnamb promoted bone healing in critical-size calvarial defects.