Multiple calcifying hyperplastic dental follicles: comparison with hyperplastic dental follicles.

Background: Multiple calcifying hyperplastic dental follicles (MCHDF) is a rare disorder that is characterized by multiple impacted teeth and enlarged dental follicles that include calcifications. The current lack of information characterizing MCHDF impedes clinicians from making prompt differential diagnoses. We describe five cases of MCHDF and analyze their clinical and histopathological features in an effort to compare MCHDF with hyperplastic dental follicles (HDF) of singly impacted teeth.

Methods: Our five cases of MCHDF were examined and clinically/histologically compared with data from 50 singly impacted teeth with HDFs.

Results: The five patients described in this study were all male. The pattern of impaction varied, but every second molar was impacted in all the patients. Alterations in the number of teeth, such as supernumerary or congenitally missing teeth were observed. Upon microscopic examination, most of the calcifications consisted of basophilic droplets that were fused to one another, and were surrounded by whirling spindle cells. Another type of calcification that was observed less frequently resembled woven bone. These features were consistent with three previously reported cases and observed in HDFs of 20 singly impacted teeth. While the average period of impaction and the time to reach some level of calcification in MCHDFs was shorter than in single calcifying HDFs, the calcification was more generalized in MCHDFs.

Conclusions: This study indicates that MCHDF is a separate pathologic entity with exclusive male predilection and earlier calcifications, different to HDF. Further studies are needed to understand the etiology of MCHDFs to provide various options for treatment, and to clarify the mechanisms of eruption.