Common Odontogenic Lesions Research Articles

A proteomics study to explore differential proteins associated with the pathogenesis of ameloblastoma.

Reports on the proteomic studies of ameloblastoma and other common odontogenic lesions are limited. We thus explored the differential proteins among ameloblastoma, odontogenic keratocyst, dentigerous cyst, and normal gingival tissue using proteomics and identified hub proteins involved in the local aggressiveness and recurrence of ameloblastoma. Samples were obtained from 14 patients with ameloblastoma, 6 with odontogenic keratocyst, 9 with a dentigerous cyst, and 5 with normal gingival tissue. Proteins were then extracted, purified, quantified, and analysed using Easy-nLC chromatography and mass spectrometry. Further functional annotation and enrichment analyses were performed using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes on the target protein collection. Protein clustering and protein-protein interaction network analyses were used to screen the hub proteins. Proteins with significant interactions were screened according to their degree index. These results were verified by immunohistochemical staining. Proteins meeting the screening criteria of expression difference ploidy >1.2-fold (upregulation and downregulation) and p < 0.05 were considered differential proteins. In ameloblastoma, 808 differential proteins were upregulated and 505 were downregulated compared with those in odontogenic keratocyst; 309 were upregulated and 453 were downregulated compared with those in dentigerous cyst; and 2210 were upregulated and 829 were downregulated compared with those in normal gingival tissue. The three groups of differential proteins were associated with cellular exosomes, antigen binding, complement activation, human papillomavirus infection, focal adhesion, cell adhesion molecules, and metabolic pathways. CDH3 is associated with the local aggressiveness and recurrence of ameloblastoma and is a potential therapeutic target.

Complex Composite Odontoma: A Cause of Impacted Teeth

Odontomas are one of the most common odontogenic lesions, earlier considered as mixed odontogenicneoplasms but lately have been accepted as hamartomatous malformations. They are either detectedaccidentally on radiographs or when they are a cause of impeding normal eruption of teeth. Odontomasoriginate from the odontogenic tissue and contain enamel and dentine, hence are referred to as compositelesions. They can be of two types depending on the appearance. If they have masses of calcified structuresresembling multiple miniature teeth then they are called compound odontomas and if they appear as anirregular disorganized radiopaque mass they are referred to as complex odontomas. A case if complexodontoma is reported herewith which led to impacted maxillary molar.

Diagnosing the most common odontogenic cystic and osseous lesions of the jaws for the practicing pathologist

Odontogenic cysts and osseous lesions are often seen as challenging diagnostic lesions but the majority of them are easily classified. This article outlines the diagnostic features required for separating the most common of odontogenic cysts and select osseous lesions of the jaws. Clinical and radiographic findings of these jaw lesions often lead to a differential diagnosis that only the histologic findings will clarify. Dentigerous cyst, keratocystic odontogenic tumor, and certain ameloblastomas that have cystic change, may have identical radiographic findings, with only separation by their specific histologic features leading to the significantly different treatments required for each. Conversely, some cystic lesions can appear histologically identical and cannot be diagnosed without the radiographic findings. Certain osseous lesions of the jaws are particularly problematic for diagnosis without the appropriate radiographic findings, and the diagnosis should probably not be attempted on the histologic findings alone. This article will integrate the necessary clinical, radiographic, and histologic findings required to address the most common odontogenic lesions.

Application of diffusion kurtosis imaging to odontogenic lesions: Analysis of the cystic component.

To assess the feasibility of applying diffusion kurtosis imaging (DKI) to common odontogenic lesions and to compare its diagnostic ability versus that of the apparent diffusion coefficient (ADC) for differentiating keratocystic odontogenic tumors (KCOTs) from odontogenic cysts. Altogether, 35 odontogenic lesions were studied: 24 odontogenic cysts, six KCOTs, and five ameloblastomas. The diffusion coefficient (D) and excessive kurtosis (K) were obtained from diffusion-weighted images at b-values of 0, 500, 1000, and 1500 s/mm2 on 3T magnetic resonance imaging (MRI). The combination of D and K values showing the maximum density of the probable density function was estimated. The ADC was obtained (0 and 1000 s/mm2 ). Values for odontogenic cysts, KCOTs, and ameloblastomas were compared. Multivariate logistic regression modeling was performed to assess the combination of D and K model versus ADC for differentiating KCOTs from odontogenic cysts. The mean D and ADC were significantly higher for ameloblastomas than for odontogenic cysts or KCOTs (P < 0.05). The mean K was significantly lower for ameloblastomas than for odontogenic cysts or KCOTs (P < 0.05). The mean values of all parameters for odontogenic cysts and KCOTs showed no significant differences (P = 0.369 for ADC, 0.133 for D, and 0.874 for K). The accuracy of the combination of D and K model (76.7%) was superior to that of ADC (66.7%). Use of DKI may be feasible for common odontogenic lesions. A combination of DKI parameters can be expected to increase the accuracy of its diagnostic ability compared with ADC. J. Magn. Reson. Imaging 2016;44:1565-1571.

Radiological challenges in distinguishing keratocystic odontogenic tumor from ameloblastoma: an extraordinary occurrence in the same patient

ObjectivesThe aims of this study are to describe the radiological appearance of two common odontogenic lesions (keratocystic odontogenic tumor and ameloblastoma) arising in the same patient simultaneously with their radiological differences and histological correlates, and to describe challenges in radiological diagnosis. DesignSingle case report. SettingTertiary referral center. ParticipantsForty-one year-old African-American male patient. Main outcome measureLesion appearance on computed tomography (CT) scan and pathological correlates. ResultsA 41year-old African-American male presented with asymptomatic right maxillary swelling. A CT scan of the maxillofacial skeleton showed and expansile and cystic lesion of the right hemimaxilla with trabecular osseous expansion, and a left cystic lesion in the left hemimaxilla expanding into the pterygopalatine fossa. Biopsy confirmed the suspected diagnoses of right ameloblastoma and left keratocystic odontogenic tumor. ConclusionAlthough they are among the most common odontogenic tumors, the presence of concurrent ameloblastoma and KOT is an exceedingly rare occurrence in the same patient. The appearance on CT scan may help in distinguishing ameloblastoma from KOT by looking at bone expansion and high density areas, although the gold standard diagnostic test remains open biopsy.

Expression of Bcl-2 in Primary and Recurrent Odontogenic Keratocysts in Comparison with Other Odontogenic Lesions.

To determine the biological behaviour of common odontogenic cystic lesions by analysing and comparing bcl-2 expression amongst them. Our study covered 90 formalin fixed paraffin embedded tissue samples: 26 primary cases each of radicular cysts (RC), dentigerous cysts (DC) and odontogenic keratocysts (OKC) and 12 of recurrent OKCs. Bcl-2 expression was analysed immunohistochemically and data analysis was accomplished using SPSS version 17.0. Means were taken for age while for gender and site of the lesions frequencies and percentages were determined. The Chi-square test was applied to evaluate any statistically significant difference of bcl-2 expression in these lesions and p value of ≤0.05 was taken as significant. All the recurrent OKCs showed a strong positivity for bcl-2 that was absent in all of its primary cases (p value<0.05). Although variation in expression of bcl-2 was not found to be statistically significant between RC and DC, however, it became significant when all primary cases of these common odontogenic lesions were compared. Recurrent OKC showed comparatively a more aggressive behaviour than their primary counterparts and also from RC and DC. Bcl-2 proved to be a valuable adjunct in determining aggressive biological behaviour of odontogenic lesions.

Erupted complex composite odontoma: Report of two atypical cases

Odontomas are nonaggressive, hamartomatous developmental malformations of odontogenic origin. They are considered one of the most common odontogenic lesions composed by diverse dental tissues. They may interfere with the eruption of an associated tooth and are more prevalent in the posterior mandible. The eruption of a complex odontoma into the oral cavity is rare. Here, we report such two rare cases of gigantic erupted complex composite odontomas.

Prevalence of ameloblastoma: A three-year retrospective study

Context: This study intends to assess the data on the prevalence and types of ameloblastoma reported in the Outpatient Department retrospectively, so that the distribution of ameloblastomas among this geographic area can be reported. Aims: To retrospectively analyze and evaluate the distribution and frequency of ameloblastoma cases based on the gender and histopathological types. Settings and Design: Retrospective study. Materials and Methods: Radiographs and biopsy records of all histologically diagnosed cases of ameloblastoma archived from January 2010 to December 2012 were retrieved from the Outpatient Department. Statistical Analysis: Descriptive statistics were performed to calculate the frequency and percentages of these variables. Age was stratified into various groups at 15-year intervals. The chi-square test for differences between two groups and the analysis of variance (ANOVA) test for differences among three or more groups were used. The level of statistical significance was set at P < 0.05. Results: From the data of ameloblastoma patients, about 30 cases were short-listed and their data was analyzed. It was found that the 15-30 year old age group had the highest percentage of occurrence (about 46.6%) among all cases. Frequently the posterior segment and vertical ramus of the mandible was involved. Radiographically, unilocular appearance was noted in 50% of the cases and unicystic ameloblastoma was the most frequently encountered histological subtype (49.9%). Conclusion: Studies on the incidence of ameloblastoma among the Indian population is rare. By performing a meta-analysis at the level of societies and geographic places, we can identify the demographic distribution of common odontogenic lesions like ameloblastoma among the various populations.

Immunohistochemical Expression of PCNA in Epithelial Linings of Selected Odontogenic Lesions.

Though odontogenic lesions have in common origin from the primitive odontogenic epithelium , there is a diversity in their initiation behavior and growth. The aggressive nature of odontogenic keratocyst similar to ameloblastoma in comparision with the other common odontogenic (dentigerous and radicular) cyst could be due to possible differences in their epithelial linings. PCNA (Proliferating cell nuclear antigen) is a cell cycle related antigen, used in the study of cell kinetics of these epithelial linings, to corelate the biological behaviour among these common odontogenic lesions. This paper has intended to study the cell kinetics of 4 selected odontogenic lesions (dentigerous cyst, radicular cyst,odontogenic keratocyst and ameloblastoma) to demonstrate differences in their epithelial linings. Sixty samples of paraffin embedded tissue specimens (archival tissues) were included (15 radicularcysts, 15 odontogenic keratocysts; 15 dentigerous cysts and15 Ameloblastoma. Among cyst OKC had higher values than DC and RC. When staining results of all the cyst were compared individually with ameloblastoma ,the staining results of OKC was similar to ameloblastoma ,and ameloblastoma presented higher values than OKC (p=0.000). The results of this study show 1) Though OKC and DC are developmental in origin and radicular cyst is inflammatory, OKC has intrinsic growth potential among these cyst 2). Ameloblastoma has similar proliferative potential as OKC and hence it has been reinforced as KCOT(Keratocystic odontogenic tumour) in the recent classification.