Calcifying odontogenic cyst with atypical features
A 43-year-old male electrician reported to our center for prosthetic replacement of his missing lower posterior teeth. His medical history and dental history was non-contributory except that he had multiple uneventful extractions of mandibular second and third molars as well as maxillary third molars several months back. On clinical examination, no abnormalities were observed, except for an indistinct, nontender, hard bulge over the right maxillary canine-lateral incisor region on palpation and also had attrition of anterior teeth. The right maxillary canine and lateral incisor appeared to be diverged. Few posterior teeth also had dental caries in various stages. Routine panoramic examination revealed a radiolucent lesion in the right anterior region, measuring 1.7 cm × 1.4 cm []. The oval, radiolucent lesion involved the distal part of the root of lateral incisor, the apex, and mesial part of the root of the right maxillary canine with diffuse margin. Closer radiological examination with periapical radiography revealed that the maxillary right canine root was in juxtaposition with the entity while the lateral incisor had a loss of lamina dura []. Clinically, there was a delayed response to pulp vitality test, indicating a compromise in pulpal vitality in both the teeth.\nThe patient had a parafunctional, occupation related habit of traumatizing his canines repeatedly. Based on the history, radiographic finding, clinical presentation, and pulpal vitality test a provisional diagnosis of periapical granuloma was made. Clinical differential diagnosis of a lateral periodontal cyst, squamous oontogenic tumor, and globulomaxillary cyst were considered. The nontender, indistinct, clinical bulge was attributed as a reactive, buccal cortical expansion of this probable long-standing condition. Uneventful, single visit root canal treatment was done in canine and lateral incisors. The curettage of the periapical granuloma was planned after root canal treatment.\nOn elevating a wide, semilunar flap, a well-circumscribed area of elevated, thinned cortex was identified []. On removal of the bone over the lesional area, an ovoid fluctuant, swelling with what clinically appeared to be a thick capsule was identified. Carefully, the margins were explored and the entire lesion was removed in total after careful blunt dissection []. The residual bone was clear with no evidence of cystic lining []. The entire area was thoroughly curetted till healthy bone with pinpoint bleeding spots in bone appeared. Apicectomy and retrograde filling was done in lateral incisor and canine. The area was irrigated with Povidone-Iodine, saline, and primarily closed.\nThe macroscopic appearance was nonspecific, except for the prominent superficial vasculature [Figure and ]. The cystic mass was subjected to histopathological study. The lesion exhibited cystic lumen lined by a thin layer of odontogenic epithelium (OE). The basal layer of this OE was made up of palisaded columnar or cuboidal cells, resembling ameloblasts of varying thickness. The hyperchromatic nuclei of these cells were polarized away from the basement membrane. These cells were overlined by loosely arranged epithelial cells resembling stellate reticulum. There were a number of epithelial ghost cells which were devoid of nuclei, eosinophilic, and retaining their basic cell outline. These eosinophilic ghost cells were often, enlarged, and were of different shape with well-defined outlines. A few of them contained nuclear remnants [].\nIn one area of the section, thickening of OE was seen. In such areas, islands of odontogenic cells were arranged in the form of thin anastomosing strands in a plexiform and lattice-work pattern. Toward the center of the lesion, in this area, arrangement of ameloblast-like cells in the form of ductal or rosette pattern was observed []. In the center of this ductal arrangement was a pale, eosiniophilic material with varying texture and pattern. Also in one particular foci, cholesterol clefts were identified []. Based on the histopathological picture, a diagnosis of COC with AOT-like areas was made.\nThe healing was uneventful and patient was followed up for 6 months with no evidence of recurrence.