Odontogenic keratocyst and ameloblastoma: radiographic evaluation

Objectives

To describe the radiographic features of odontogenic keratocysts (OKCs) and ameloblastomas and to compare the radiographic findings between these 2 lesions.

Methods

Radiographs of OKCs and ameloblastomas were retrospectively reviewed. Location, border, shape, association with impacted tooth, tooth displacement, root resorption, and bone expansion were evaluated. Chi-squared or Fisher’s exact tests were used for statistical analysis. A p value?<?0.05 was considered to indicate statistical significance.

Results

One hundred OKCs and 101 ameloblastomas were reviewed. The ratios of maxilla to mandible were 1:1.4 and 1:9.1 in OKCs and ameloblastomas, respectively. All evaluated features significantly differed between OKCs and ameloblastomas (p?≤?0.001). Most OKCs showed smooth border (60%) and unilocular shape (82%), while most ameloblastomas showed scalloped border (77.2%) and multilocular shape (68.3%). Association with impacted tooth was found in 47% of OKCs and 18.8% of ameloblastomas. Adjacent tooth displacement was found in 33.7% of OKCs and 55.8% of ameloblastomas. Root resorption was more common in ameloblastomas (66.7%) than in OKCs (7%). Bone expansion was also more common in ameloblastomas (96.3%) than in OKCs (63.6%).

Conclusion

A unilocular radiolucent lesion with smooth border, no adjacent tooth displacement, no root resorption and causing mild or no bone expansion is suggestive of an OKC rather than an ameloblastoma.

     

Odontogenic keratocyst with dentinoid formation

Although rare, hard tissue deposits, namely dystrophic calcifications and cartilage, have been reported to occur in the connective tissue wall of the odontogenic keratocyst. However, dentinoid formation has not been previously documented. A case involving the left mandibular premolar-molar region in a 37-year-old Malay male is described here along with a brief review on the reported prevalence of hard tissue deposits in the odontogenic keratocyst. Differential diagnosis of this case from other dentinoid-forming odontogenic cysts and tumors-notably calcifying odontogenic cyst, odontoma, ameloblastic fibro-odontoma, central odontogenic fibroma and adenomatoid odontogenic tumor that may present with dentin/dentinoid formation-is discussed.     

Odontogenic keratocyst of the maxilla: a case report

Remnants of odontogenic epithelium persist in oral tissues after odontogenesis is complete, and from these remnants a variety of tumours and cysts can arise. Squamous metaplasia can occur in this epithelium which in turn may produce keratin. Although keratin production is a feature of many odontogenic cysts, a specific entity, the odontogenic keratocyst has been defined. The term was first introduced by Philipsen in 1956 and has been used synonymously with that of the primordial cyst. Its capacity for aggressive growth and recurrence even after many years makes it of special interest. In this case report these behavioural characteristics are well demonstrated. The long natural history of the condition in this case and its site and size involved oral, ophthalmic and ultimately otolaryngologic surgeons.     

Odontogenic keratocyst in an infant.

Odontogenic keratocysts occur as solitary lesions or in association with the basal cell naevus syndrome (BCNS), and have been documented in the age range 5 to 83 years. A rare case of an odontogenic keratocyst in a one-year-old girl is presented. Its characteristic tendency to recur, and its association with BCNS present important clinical implications.     

Odontogenic keratocyst in maxillary sinus with invasive behaviour

Odontogenic keratocyst is a cystic lesion characterized by a high rate of recurrence. This report describes a rare case of ciliated epithelium-lined odontogenic keratocyst in the maxilla of a 27-year-old female. Panoramic radiography showed a lytic lesion on the right maxilla associated with an impacted molar tooth. Computerized tomography image revealed the involvement of the lesion with the right maxillary sinus, destroying the sinus floor. Histopathologically, the typical keratinized epithelial-lined cyst of odontogenic keratocyst abruptly changed into a ciliated epithelium, suggesting the fusion of both these epithelia rather a metaplastic transformation. The biological behaviour of odontogenic keratocysts is discussed.     

Odontogenic keratocyst associated with an intramandibular chondroma.

The unusual feature of an intramandibular chondroma in association with an odontogenic keratocyst in a 59-year-old man is described. The keratocyst recurred and required two reoperations. The coexistence of an odontogenic keratocyst and a chondroma of the jaw was probably a coincidence of two simultaneous but otherwise unrelated lesions. The possibility that the keratocyst and the chondroma were due to a single developmental disturbance of the region cannot be excluded. No signs of a recurrence were seen at the last follow-up examination four years after the operation.     

Odontogenic keratocyst expresses vascular endothelial growth factor: an immunohistochemical study

Background:  Vascular endothelial growth factor (VEGF) expression may act as a sensitive measure of the angiogenic potential of a lesion. Furthermore, VEGF has been implicated in the pathogenesis of cystic tumors and inflammatory odontogenic cysts. Thus, we studied the expression of VEGF in the epithelium of odontogenic keratocyst (OK) in association with cell proliferation and apoptosis.
Methods:  Forty-two cases of OK, 26 cases of dentigerous cyst (DC), and 15 cases of residual cyst (RC) were retrospectively examined by immunohistochemistry for VEGF, Ki67/Mib-1 and anti-caspase-3. For VEGF and caspase-3, the intensity of immunostaining was qualitatively assessed, while for the evaluation of Ki67 the average number of positively stained nuclei in 10 high-power microscopic fields (×400) was calculated.
Results:  The VEGF expression was stronger in OK when compared with DC ( P  < 0.007). The rate of nuclear Ki67 expression in OK was significantly higher than that in DC ( P  < 0.001) and RC ( P  < 0.001). Cytoplasmic caspase-3 expression was statistically more intense in RC than in OK ( P  = 0.001) or DC ( P  < 0.001). A statistically significant correlation was seen in OK for Ki67 ( P  < 0.001) and VEGF ( P  = 0.023), but not for caspase-3. Multiple regression analysis revealed a linear relationship between VEGF and Ki67.
Conclusions:  The VEGF was expressed in the epithelium of OK, DC, and RC with a variable intensity, and in OK VEGF expression was related to Ki67. It is suggested that VEGF expression by the odontogenic epithelium is not induced solely by inflammation.     

临床和影像学表现易被误诊的牙源性角化囊肿

本文报道1例以左侧下颌前磨牙区颊侧轻度疼痛和牙龈肿胀为主诉的82岁女性病例。最初怀疑为牙周脓肿并做了相应的治疗。根尖片也显示出了活动性牙周炎导致的牙槽骨水平吸收，并且以肿胀区左侧下颌前磨牙病变为重。但是．在对病变区域和可疑病原牙进行包括牙髓活力测试在内的详细检查后．认为牙体或牙周疾病的可能性不大。随后的病理检查确诊为牙源性角化囊肿。本病例的特点是临床和影像学表现的非典型性．早期诊断和针对性的治疗可以有效地减低牙源性角化囊肿的复发，但是将其误诊为牙周或是牙体牙髓疾病却有可能导致错误的治疗和不必要的并发症。