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Background: It is occasionally difficult to distinguish the stellate reticulum-like region of ameloblastoma from the fibrous connective tissue stroma. This difficulty is further pronounced in the plexiform variant of ameloblastoma that has very sparse fibrous connective tissue.
Aim: To test the utility of Azan trichrome stain in marking tumour regions and the peri-tumour environment of ameloblastoma.
Materials and Methods: Sections were prepared for 18 formalin fixed paraffin-embedded blocks of ameloblastoma cases and stained with Azan trichrome stain according to the manufacturer's specification.
Results and Conclusions: The tumour areas were stained mostly brown, with the ameloblasts mainly marked as deep brown while the stellate reticulum-like region was light brown. The structures in the peri-tumour region were marked with different shades of blue. Azan trichrome staining was able to distinguish between the fibrous connective tissue and the stellate reticulum-like areas in 100% of the cases.
Background: Osteoinductive bone substitutes are defined by their ability to induce new bone formation even at heterotopic implantation sites. The present study was designed to analyze the potential osteoinductivity of two different bone substitute materials in caprine muscle tissue.
Materials and methods: One gram each of either a porous beta-tricalcium phosphate (β-TCP) or an hydroxyapatite/silicon dioxide (HA/SiO2)-based nanocrystalline bone substitute material was implanted in several muscle pouches of goats. The biomaterials were explanted at 29, 91 and 181 days after implantation. Conventional histology and special histochemical stains were performed to detect osteoblast precursor cells as well as mineralized and unmineralized bone matrix.
Results: Both materials underwent cellular degradation in which tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells and TRAP-negative multinucleated giant cells were involved. The ß-TCP was completely resorbed within the observation period, whereas some granules of the HA-groups were still detectable after 180 days. Neither osteoblasts, osteoblast precursor cells nor extracellular bone matrix were found within the implantation bed of any of the analyzed biomaterials at any of the observed time points.
Conclusions: This study showed that ß-TCP underwent a faster degradation than the HA-based material. The lack of osteoinductivity for both materials might be due to their granular shape, as osteoinductivity in goat muscle has been mainly attributed to cylindrical or disc-shaped bone substitute materials. This hypothesis however requires further investigation to systematically analyze various materials with comparable characteristics in the same experimental setting.
Introduction: ameloblastoma is a slow growing, painless odontogenic swelling which can attain sizes that result in severe deformities of the craniofacial complex. It is the most commonly encountered odontogenic tumor in Nigeria. Surgical intervention is currently the method of treatment; however identification of altered molecular pathways may inform chemotherapeutic potential. The Protein Patched homolog 1 (PTCH-1) is overexpressed in ameloblastoma. Also, mutation in the MDM2 gene can reduce the tumor suppressor function of p53 and promote ameloblastoma growth. No study however has characterized the molecular profile of African cases of ameloblastoma with a view to developing chemotherapeutic alternatives. The objective was to characterize the PTCH-1 genetic profile of Ameloblastoma in Nigerian patients as a first step in investigating its potential for chemotherapeutic intervention.
Methods: twenty-eight FFPE blocks of ameloblastoma cases from Nigerian patients were prepared for antibody processing to PTCH-1 (Polyclonal Anti-PTCH antibody ab39266) and MDM2 (Monoclonal Anti-MDM2 antibody (2A10) ab16895). Cytoplasmic brown staining was considered as positive for PTCH while nuclear staining was positive for MDM2.
Results: moderate and strong expressions for PTCH in ameloblast and stellate reticulum were 78.6% and 60.7% respectively. Only 3 (10.7%) cases expressed MDM2.
Conclusion: the importance of our study is that it supports, in theory, anti-PTCH/SHH chemotherapeutics for Nigerian ameloblastoma cases and also infers the possible additional use of anti-p53 agents.