Orthokeratinized odontogenic cyst (OOC) was initially defined as the uncommon orthokeratinized type of keratocyst (OKC) by World Health Organization (WHO). Several studies have shown that OOC has different clinicopathologic aspects when compared with other developmental cysts, especially OKC. So now emerges to be a distinct entity, according 4th edition WHO Classification Head and Neck Tumors w...