Orthokeratinizing odontogenic cyst of maxilla with complex odontoma

Orthokeratinised odontogenic cyst: A case series

Orthokeratinised odontogenic cyst (OOC) is a distinct and an uncommon odontogenic cyst of jaw. It was previously considered as orthokeratinized variant of Odontogenic Keratocyst, owing to its same site, age and occurrence and origin. In 2017 WHO classified OOC under odontogenic cysts as a distinct entity, clearly separating it from Odontogenic Keratocyst (OKC). In cases of malignant transformation, the cyst shows unclear boundaries. The cases that reported to the department during the period 2019-2021 were retrieved and then reviewed by the authors. A total of 7 cases that met the histopathological criteria for OOC were included in the study. There was a clear male predilection. Age of patients ranged between 17 to 65 years. Most of cases showed Unilocular radiolucency but one case revealed Multilocular pattern. Grossly specimens ranged between 0.5 cm to 3.0cms. Histopathological findings showed all classic features of OOC. FNAC was also done and it is clearly evident that the use of Cytology can help us diagnose the cyst early and is a less invasive method. OOC is a rare type of odontogenic cyst, but while making the diagnosis one should not forget about the fact that it is less aggressive and needs to be differentiated from OKC. Majority times it has been seen that Clinico-radiographic diagnosis given of any circumscribed radiolucency around an impacted tooth is Dentigerous cyst, which is not correct. Diagnosing such lesions require thorough histopathological and radiographical correlation along with molecular analysis to reach final diagnosis.

Incidental finding of orthokeratinized odontogenic cyst with unusual features

Orthokeratinized odontogenic cyst (OOC) is a rare developmental odontogenic cyst occurring in the jaw with debated etiology. It was originally believed to be a variant of odontogenic keratocyst (OKC) but is now considered to be a distinct entity. The majority of the cases occur in the third and fourth decades of life. The common site is the mandibular posterior region with a male predilection. Swelling is the most common symptom which may be accompanied by pain, although in most cases, the lesion is asymptomatic. These lesions mostly present as unilocular radiolucency often associated with an impacted tooth. They may mimic dentigerous cyst and OKC in radiologic and histopathologic presentation, however, differ in biological behavior, pathogenesis and prognosis in comparison. Hence, making an accurate diagnosis is essential. This article describes an incidental finding of OOC in a 28-year-old female during radiographic investigation for orthodontic treatment. This case showed some rare features such as multilocular radiolucency, nonkeratinized epithelium in areas of inflammation, few cholesterol clefts with giant cells, presence of dentinoid-like material and dystrophic calcification in the capsule.

Orthokeratinized odontogenic cyst with calcification: A rare case report of a distinct entity

Orthokeratinized odontogenic cyst (OOC) is a relatively rare odontogenic cyst, distinct from odontogenic keratocyst (OKC). In the 4^th edition of WHO Classification of Head and Neck Tumors (2017), OOC has been included as a separate entity in the category of developmental odontogenic cysts. It presents as a unilocular radiolucent lesion in the posterior mandible and is frequently related to impacted teeth, thus mimicking dentigerous cyst. Due to low local aggressiveness and no association with nevoid basal cell carcinoma syndrome, it does not show tendency to recur. When compared to OKC, OOC exhibits substantial number of differences with respect to clinical, pathological and behavioral features and treatment modalities. Hence, recognizing OOC as unique lesion is mandatory to avoid unnecessary overtreatment. This paper aims to report a rare case of OOC associated with impacted tooth, showing calcifications and emphasizes its differences from OKC. Furthermore, the recent concepts about OKC and OOC are discussed.

Orthokeratinized odontogenic cyst of the mandible: A rare case report with a systematic review

Orthokeratinized odontogenic cyst (OOC) is an odontogenic cyst was initially termed as the uncommon orthokeratinized type of odontogenic keratocyst by the World Health Organization. It usually occurs in mandible. Various studies have shown that OOC has typical characteristic clinicopathologic features when compared to other developmental odontogenic lesions such as dentigerous cyst and the keratocystic odontogenic tumor (KCOT). Rare recurrence was noted after surgical removal of the lesion. The purpose of this article is to present a case of OOC arising in the posterior mandible and emphasize on differentiating it from the KCOT and dentigerous cyst.