Odontogenic Keratocyst: A Case Series of five Patients

In Silico Analysis of Genes Associated with the Pathogenesis of Odontogenic Keratocyst

Odontogenic keratocyst (OK) is a benign intraosseous cystic lesion characterized by a parakeratinized stratified squamous epithelial lining with palisade basal cells. It represents 10-12% of odontogenic cysts. The changes in its classification as a tumor or cyst have increased interest in its pathogenesis.

OBJECTIVE

Identify key genes in the pathogenesis of sporadic OK through in silico analysis.

MATERIALS AND METHODS

The GSE38494 technical sheet on OK was analyzed using GEOR2. Their functional and canonical signaling pathways were enriched in the NIH-DAVID bioinformatic platform. The protein-protein interaction network was constructed by STRING and analyzed with Cytoscape-MCODE software v 3.8.2 (score > 4). Post-enrichment analysis was performed by Cytoscape-ClueGO.

RESULTS

A total of 768 differentially expressed genes (DEG) with a fold change (FC) greater than 2 and 469 DEG with an FC less than 2 were identified. In the post-enrichment analysis of upregulated genes, significance was observed in criteria related to the organization of the extracellular matrix, collagen fibers, and endodermal differentiation, while the downregulated genes were related to defensive response mechanisms against viruses and interferon-gamma activation.

CONCLUSIONS

Our in silico analysis showed a significant relationship with mechanisms of extracellular matrix organization, interferon-gamma activation, and response to viral infections, which must be validated through molecular assays.

An Insight Into the Effect of Odontogenic Keratocysts on Surrounding Structures: Cone-Beam Computed Tomography-Based Analysis of Cases

Introduction  An odontogenic keratocyst (OKC) is a benign intraosseous lesion with potential to demonstrate aggressive and invasive behavior. The aim of this retrospective study was to analyze the imaging features of the OKC using cone-beam computed tomography (CBCT) and to evaluate the association between the internal structure of the lesion and the effect of the lesion on surrounding structures. Methods Overall, 32 CBCT scans of histopathologically diagnosed cases of OKC were analyzed retrospectively. The following variables were analyzed: anatomic location of the lesions (mandible body (right/left), ramus (right/left), mandible body+ramus (right/left), maxilla (right/left), and both jaws), the internal structure of the lesion (unilocular/multilocular), and the effect of the lesion on the surrounding anatomical structures (involvement of the inferior alveolar nerve canal (IANC), displacement of the IANC, cortical expansion, displacement of the tooth, resorption of the root, associated impacted tooth, associated missing tooth). We also looked for the association between the internal structure and the effect of the lesion on anatomic structures. Results Out of 32 cases, 29 (90.6%) cases involved the mandible alone. Statistically significant association (p-value 0.005) was present between the internal structure and mean age of presentation as well as between the internal structure and impacted tooth (p-value 0.027). The association between the internal structure and other variables was statistically not significant. Conclusions The radiographic features of OKCs can be variable, and these lesions have a considerable effect on the tooth, IANC, and cortical bone. Significant association was found between the internal structure, age, and impacted tooth. Since OKCs have a high recurrence rate, CBCT is advised for evaluating the extent and location of any cortical perforations.

Keratocystic odontogenic tumor with an ectopic tooth in maxilla

The term odontogenic keratocyst was first used by Philipsen in the year 1956. The lesion was renamed by him as keratocystic odontogenic tumor (KCOT) and reclassified as odontogenic neoplasm in the World Health Organization's 2005 edition that occurs commonly in the jaws having a predilection for the angle and ascending ramus of mandible. In contrast, KCOTs arising in the maxillary premolar region are relatively rare. Here, we discuss a rare case of keratocystic odontogenic tumor occurring in the maxilla with an ectopic tooth position.