Collagen during odontogenesis and in ameloblastoma: A polarizing microscopic study

BACKGROUND: Odontogenesis is a highly coordinated and complex process which depends on cell–cell interactions that result in initiation and generation of tooth. Tissue remnants of developing tooth can form odontogenic tumors possibly, reflecting different developmental stages in tooth formation. In both odontogenesis and odontogenic tumors, stroma plays a prominent role in maintaining epithelial tissues with continuous molecular interactions. As the collagen forms an integral part of connective tissue stroma, in the present study, polarization colors and thickness of the collagen fibers were assessed in both tooth germ papillae and ameloblastoma using picrosirius red (PSR) stain. MATERIALS AND METHODS: Collagen fibers in 20 cases of ameloblastoma and 10 tooth germs from the human fetus were evaluated with PSR stain and examined under polarizing microscopy. RESULTS: Polarization colors of red-colored collagen fibers with greater diameter were more in ameloblastoma when compared to tooth germ papillae in which green-colored collagen fibers with smaller diameter being more. CONCLUSION: The absence of hard tissue formation in ameloblastoma might be due to the presence of significantly more number and greater thickness of red-colored collagen fibers. Thus, the nature of collagen fibers can predict the nature in terms of biologic behavior and prognosis.