Plexiform unicystic ameloblastoma: a diagnostic problem in dentigerous cysts

Area of Science:

• Oral Pathology
• Odontogenic Tumors
• Surgical Pathology

Background:

• Dentigerous cysts can exhibit epithelial proliferation patterns.
• Histologic criteria for ameloblastoma can be challenging to apply to certain patterns within cysts.
• Distinguishing between ameloblastoma and epithelial hyperplasia in these cases is clinically significant.

Purpose of the Study:

• To investigate a specific plexiform pattern of epithelial proliferation found in dentigerous cysts.
• To determine if this pattern represents ameloblastoma or epithelial hyperplasia.
• To propose a diagnostic term for this specific lesion.

Main Methods:

• Histologic examination of 19 cases of dentigerous cysts with plexiform epithelial proliferation.
• Review of available clinical information for these cases.
• Comparison with established histologic criteria for ameloblastoma.

Main Results:

• Ameloblastoma was histologically confirmed in association with the plexiform pattern in 9 out of 19 cases.
• One case exhibiting only the plexiform pattern recurred, supporting its neoplastic nature.
• The proposed Vickers and Gorlin criteria were found to be too rigid for this specific pattern.

Conclusions:

• The plexiform pattern in dentigerous cysts is concluded to be a form of ameloblastoma.
• "Plexiform unicystic ameloblastoma" is proposed as a term for this lesion.
• Treatment recommendations vary based on the extent of proliferation (cystic lumen vs. periphery).