Imaging Characteristic of 11 Lesions of Odontogenic Keratocyst in the Indian Subpopulation: A Cone-Beam Computed Tomography Experience

Abstract

Background: The clinical feature and radiographic appearance of orthokeratinized odontogenic keratocyst (OKC) are not characteristic, which may lead to the misdiagnosis. The radiographic appearance of OKC may range from a small unilocular radiolucency to a large multilocular radiolucency, resembling other odontogenic cysts and tumors.

Aim: The aim was to illustrate the characteristic feature of OKC presented on the digital panoramic radiograph and cone-beam computed tomography (CBCT), which may provide great value for the differential diagnosis and the treatment planning and also to compare the various radiographic features of OKC in CBCT and digital panoramic radiograph.

Materials and methods: Digital panoramic and CBCT records of seven cases, with 11 lesions of OKC were analyzed retrospectively from the patients' database from our institute (2014 to 2016), which was histopathologically diagnosed as OKC.

Results: The mean age of the patients was 24.1 years, and the female-to-male ratio was 3: 4. Six of 11 lesions were localized within the mandible, and five lesions were in the maxilla.

Conclusion: The presurgical assessment with radiological information is extremely important for treatment planning, and CBCT provides us with an accurate and faster three-dimensional representation of a lesion at a lower dose and cost, but the role of panoramic radiograph cannot be refuted.

Keywords: Cone-beam computed tomography; keratocystic odontogenic tumor; multilocular radiolucency; panoramic radiography; unilocular radiolucency.

Figure 1

Clinical features of seven cases of odontogenic keratocysts

Figure 2

Radiological features – location, size, and internal structure: Case 1: Unilocular radiolucency extending from right ramus, crossing midline; thinning and perforation of buccal and lingual cortical plates; Case 2: Lesion located in left maxilla, with impacted 28; Case 3: Unilocular lesion located in the left maxilla in 23, 24 regions; Case 4: Unilocular lesion located in in the left maxilla in 21,22, 23, 24 and 25 regions; Case 5: Lesion present in the left mandible in ramus body region; Case 6: Multilocular scalloped lesion present in the right mandible in ramus body region; Case 7: Unilocular lesion in right mandible, in ramus region

Figure 3

Multiple odontogenic keratocyst; Case 4: In addition to the chief complaint of lesion in left maxilla (yellow arrow), another lesion was incidentally found in right mandible (yellow circle); Case 7: Similarly, apart from chief compliant lesion in right mandible, three more lesions were found in relation to 18, 28, and 38 regions (yellow circle)

Figure 4

Radiological features-impacted tooth and root resorption. (a) root of 23 displaced mesially and 24, 25 distally; (b) 22, 23 are impacted and displaced superiorly; (c and d) showing root resorption; (e) Impacted 48 displaced buccally, inferiorly and posteriorly

Figure 5

Radiological features-effect on maxillary sinus/nasal floor and inferior alveolar canal. (a) Obliteration of left maxillary sinus; (b and c) Inferior displacement of inferior alveolar canal

Figure 6

Radiological features-effect on cortical plate. (a) Thinning and expansion of lingual and more of buccal CP in right mandibular lesion; (b) Expansion and perforation of buccal and palatal cortical plate in left maxilla; (c) Expansion and perforation of labial and palatal cortical plates; (d) Significant expansion thinning and perforation of buccal and palatal CP; (e) No CP expansion