A Rare Pathological Entity of Multiple Calcified Hyperplastic Dental Follicles

Multiple calcified hyperplastic dental follicles (MCHDF) are an extremely rare condition which has been categorized as a separate pathological entity very recently. It was initially described by Sandler et al. Gardner and Radden proposed this as a separate pathological entity. This disease is characterized by multiple unerupted teeth with abundant calcifications and rests of odontogenic epithelium in enlarged dental follicles.


Introduction
Multiple calcified hyperplastic dental follicles are an extremely rare condition which is found to be associated with enlarged dental follicles. MCHDF has been described as odontogenic hamartomatous lesion that occurs in pericoronal tissues of unerupted tooth [1,2]. Most cases found in literature are found to affect young individuals [3] involving first and second molars [3][4][5][6][7].
Differentiating MCHDF from other odontogenic tumors is important as they have different pathogenesis and recurrence rates. There is always a clinical significance evaluation of enlarged dental follicles with unerupted teeth as they can turn into cysts or tumors easily. As this case is a very rare case, its rare presentation and the management have not been decided yet.
Up to now, patients are being managed multidisciplinarily.
After radiological analysis, it was decided to review the patient after three months. However, the patient revisited after two years in the year 2014 with same complaint. After clinical examination of the patient, it was decided to give a bite raising appliance to facilitate the eruption of the permanents 16, 26, 36, and 46. And later, surgical exposure of 16 and 46 was done. In subsequent visits, the patient has undergone a root canal treatment of 21 (because the tooth was nonvital due to caries). Study models were taken in order to plan the treatment as there was not enough Occlusal Vertical Dimension (OVD) for the eruption of permanent teeth.   Clinically, there was thick mucosal growth on the posterior ridge area. When considering all these factors, there was no eruption potential for the impacted teeth. It was decided to review the patient after three months. On the review appointment, it was found that thick mucosal growth is improving and teeth were not still erupting in relation to lower molar region. An incisional biopsy from 47 region including both mucosa and alveolar bone was planned (Figures 3 and 4).
Histologically, mucosa covered by acanthotic parakeratinized stratified squamous epithelium was evident. The corium is composed of loosely arranged collagen fibers with focal myxoid changes. Numerous calcifications with a few odontogenic epithelial rests are also noted. Those histopathological features were consistent with the diagnosis of multiple calcified hyperplastic dental follicles ( Figure 5).

Discussion
Multiple calcified hyperplastic dental follicles are an extremely rare presentation in the international literature. Up to 2014, only 13 cases have been reported. They seem to mostly affect young males [8]. Mostly, mandible is more affected than maxilla [8]. This case is also inconsistent with  the literature. Microscopic findings in hyperplastic dental follicle include the presence of fibrous connective tissue, wavy collagen fibers, strands and islands of odontogenic epithelium, multinucleated giant cells, and varying sizes of basophilic mineralized areas present in cementum like calcifications [9,10]. ]. The present case has also shown the histopathological features reported in the literature.
Histopathologically, MCHDF resembles WHO type of central odontogenic fibroma. Both lesions have connective tissue, odontogenic epithelium, and calcifications. The connective tissue of odontogenic fibroma is very cellular and is often interwoven with less cellular areas, while it might be quite vascular [9]. However, this case also showed more fibrous tissue and only focal myxoid changes. Moreover, WHO type of central odontogenic fibroma shows osseous development and a family trait, whereas no such features are found in MCHDF [11,12].
Radiographically, calcifying cystic odontogenic tumor, adenomatoid odontogenic tumor (AOT), and ameloblastic fibroodontoma and calcifying epithelial odontogenic tumor Case Reports in Dentistry (CEOT) may show radiopaque foci, and they may be associated with unerupted teeth [13][14][15][16]. MCHDF also shows radio opaque foci associated with unerupted teeth [13]. Therefore, radiographical differentiation from same kind of lesions is also important. The aetiology and the biological mechanisms of this disease are not yet clearly understood. There is no apparent relationship between this disease and cleidocranial dysplasia or Gardner's syndrome, two other disorders in which there are multiple unerupted teeth [9]. Some medical conditions also can cause tooth impaction such as hypothyroidism. Therefore, excluding them is also important. In this case, the patient did not have any known systemic diseases. Making a definitive diagnosis with all clinical, radiological, and histopathological features is important because the management of other similar diseases is different from this particular disease.

Conclusion
This is a case report of a young male patient who presented with unerupted multiple permanent teeth and diagnosed as multiple calcified hyperplastic dental follicles as indicated by clinical, radiological, and histological features.