Adenomatoid odontogenic tumor (AOT) is a rare, asymptomatic, slow-growing benign tumor that can be divided into three variants: follicular, extrafollicular, and peripheral. By treating AOT using an enucleation and curettage approach, recurrence can be avoided. We report a case of a 24-year-old female who presented with a lump in the right mandibular premolar area along with diastema between displaced teeth #43 and #44 and was diagnosed with extrafollicular AOT. The patient was managed with enucleation-curettage surgery without additional bone graft procedure along with routine follow-up. A successful outcome without recurrence was achieved, and diastema closure with repositioning of the displaced teeth did not require orthodontic treatment. AOT should be managed via enucleation and curettage to obtain successful outcomes without recurrence. Spontaneous bone regeneration following enucleation can be achieved without guided bone regeneration. Also, diastema closure and repositioning of displaced teeth can occur without orthodontic interventions through physiologic drift.

BACKGROUND: Adenomatoid Odontogenic Tumor (AOT) accounts for 3% of all odontogenic tumors. It has been classified by WHO as an odontogenic tumor of purely epithelial origin. The current study attempts to establish the origin of the tumor along with detailed histopathological and clinicoradiographic analysis of 43 cases of AOT.
METHODS: Forty-three cases were reviewed from the departmental archives for demographic data, radiographic features and histological features. Further, histopathological slides were stained with Picrosirius Red (PSR) and observed under polarised light.
RESULTS: A majority of the cases were seen in the anterior jaws (76.7%), and were less than 3 cms (76.7%) in greatest dimension. Equal number of cases were of follicular and extra-follicular location while one was peripheral. Predominantly solid histological pattern was noted in 53.5%. Varied sub-patterns were observed with most cases exhibiting solid nodules and strands of tumor cells. Few cases showed melanin pigmentation. Over a third of cases (37.2%) showed dentigerous cyst like areas and one case each showed features of ossifying fibroma and focal cemento-osseous dysplasia. Tumor droplets, hyaline rings within duct-like structures, dentinoid material and osteodentin showed reddish yellow birefringence when observed under polarised microscopy post PSR staining.
CONCLUSIONS: This study highlights the diverse histopathological variation of AOT with evidence to reclassify it as a mixed odontogenic tumor based on the polarising microscopic findings with PSR staining.

The objective of this study was to review the clinical, radiologic, and histologic aspects of cases of dentigerous cysts metamorphosing into different entities along with comments on the molecular factors involved in the process. A series comprising 8 cases of dentigerous cysts was performed retrospectively along with a comprehensive literature review. Two cases of dentigerous cyst converting into mucous metaplasia were included, out of which one case was transformed into ameloblastoma after a year. The other two cases were reported as acanthomatous and unicystic ameloblastoma, whereas four transitioned to AOT. The complete review of cases and literature with molecular profiling concluded that the lining of dentigerous cysts has the potential for transforming into benign odontogenic tumors. Therefore, a careful clinical and histopathological examination is crucial for the correct diagnosis. Also, a thorough molecular understanding of the cystic lining is required.

Myotonic dystrophy, also referred myotonic muscular dystrophy, is an autosomal dominant, slowly progressive, multisystem disease characterized by skeletal muscle weakness, wasting, and myotonia. A hybrid tumor of odontogenic apparatus is a lesion showing combined histopathological characteristics of two or more previously recognized odontogenic tumors and/or cysts of different categories. We, therefore, report a case of hybrid tumor (adenomatoid odontogenic tumor associated with calcifying cystic odontogenic tumor) in a myotonic dystrophic patient.

UNASSIGNED: The process of odontogenesis is complex involving epithelial-mesenchymal interactions, along with the molecular signalling pathways triggering the initiating process. The triggering factors and cells precisely involved in the pathogenesis of odontogenic cysts and tumors are unknown. There is a vast array of biomarkers used to stain different sites, thereby helpful in diagnosing and evaluating the prognosis of these cysts and tumors. In the following study, Anti Apoptotic survivin expression patterns were assessed quantitatively in 48 samples (12 each) of Reduced Enamel Epithelium, Adenomatoid Odontogenic Tumor, Odontogenic Keratocyst and Ameloblastoma.
UNASSIGNED: The Aim of this study is to assess the anti-apoptotic survivin expression in Reduced Enamel Epithelium, Adenomatoid odontogenic tumour, Odontogenic Keratocyst and Ameloblastoma.
UNASSIGNED: The present study is carried out with 12 samples in each group. Routine hematoxylin and eosin staining was performed for confirmatory diagnosis. Later Immunohistochemistry was performed using survivin antibody. Survivin protein expression was analyzed using the parameters like location, intensity, percentage of cells positivity with survivin protein and extent of staining. With the help of Olympus BX 43 microscope, with ProgRes microscope camera, the 48 slides obtained were examined. The region of interest was selected in each slide and number of cells positively stained was counted. Data was analyzed using SPSS software version 23. Descriptive for scale data, results were analysed by using ANOVA with Chi-square test for intergroup comparison.
UNASSIGNED: The results showed significant P value <0.05. Expression of survivin was highest in Ameloblastoma, followed by Odontogenic keratocyst, Adenomatoid odontogenic tumor, and Reduced Enamel Epithelium.
UNASSIGNED: Survivin was involved in the inhibition of apoptosis as well as the detailed understanding of the biological behaviour of odontogenic cysts and tumours, thereby increasing therapeutic approaches.

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Introduction: Odontogenic tumors encompass a heterogeneous group of lesions that range from hamartomatous lesions to malignancy. Considerable variation in histologic presentation can mislead their accurate diagnosis and categorization. Ameloblastoma is generally well understood and is easy to diagnose but there has been a constant change in the classification systems ever since Broca classified odontogenic tumors in the year 1867. Over the years, it has been modified by the World Health Organization with many additions and omissions. This dynamic change is based on the result and conclusions of molecular and genetic studies with the last modification in 2017. Case Report: We present two cases of females aged 32 and 60 years who reported with facial swellings, revealed the presence of distinct histopathological findings and were diagnosed as ameloblastoma with dentinoid or adenoid ameloblastoma. Literature search revealed dearth of distinct forms of ameloblastoma that show the formation of duct like structures and dentinoid. Conclusion: It is interesting to highlight such cases as the biological behavior is still unexplored due to paucity of relevant studies and follow up of patients. Understanding the pathogenesis and the histopathological characteristics of the newer entities will enable the prompt diagnosis, treatment plan and expanding the spectrum of the lesions.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s12070-023-03534-6.

UNASSIGNED: The occurrence of hybrid odontogenic lesions with two or more morphologically distinct components is a rare phenomenon and poses a diagnostic challenge. We aimed to study the clinical, radiological, and pathological features and behavior of hybrid odontogenic lesions, to enhance awareness about these rare lesions.
UNASSIGNED: Hematoxylin and Eosin slides of hybrid odontogenic lesions diagnosed between January 01, 2012 and December 31, 2020, were reviewed. Demographic and radiological information were obtained from the patient\'s medical records.
UNASSIGNED: 8 cases were diagnosed with a mean age of 19.1 years and male to female ratio of 1:1.7. Involvement of mandible was more common (n = 5) as compared to maxilla (n = 3). All patients presented with swelling for an average of 9.75 months (3-25 months) duration. Bleeding, loose teeth, pain and facial asymmetry were reported in 5,3, 3, and 2 cases, respectively. Radiologically, 7 cases were well demarcated, 75% cases (n = 6) were radiolucent, and average radiological size was 4.8 cm. All patients were managed with surgery alone. 5 cases (62.5%) underwent enucleation and curettage, while local excision, en-block resection and segmental mandibulectomy were performed in 1 case each. Histologically, ossifying fibroma/cemento-ossifyiong fibroma were the most lesion, occurring in 5 cases (62%), followed by giant cell granuloma like lesions (GCG) i.e., central and peripheral giant cell granuloma (n = 3), Adenomatoid Odontogenic tumor (AOT) (n = 2), and DC (n = 2), ameloblastic fibroma (AF) (n = 1), Ameloblastoma (n = 1), calcifying odontogenic cyst (COC) (n = 1), and complex odontoma (n = 1). No evidence of recurrence was noted after 4-99 months of surgery (mean: 32.9) in cases with available data (n = 7). Long-term complaints included facial asymmetry (n = 2) and pain (n = 1).
UNASSIGNED: Most hybrid odontogenic lesions affect young females in the second decade of life and commonly show COF and OF as hybrid components. A conservative approach to management appears adequate.

BACKGROUND: This study aimed to investigate the differentiation of ameloblastic-like cells and the nature of the secreted eosinophilic materials in adenomatoid odontogenic tumors.
METHODS: We studied histological and immunohistochemical characteristics of 20 cases using: cytokeratins 14 and 19, amelogenin, collagen I, laminin, vimentin, and CD34.
RESULTS: Rosette cells differentiated into ameloblastic-like cells positioned face-to-face, displaying collagen I-positive material between them. Epithelial cells of the rosettes can differentiate into ameloblastic-like cells. This phenomenon probably occurs due to an induction phenomenon between these cells. The secretion of collagen I is probably a brief event. Amelogenin-positive areas were interspersed by epithelial cells in the lace-like areas, outside the rosettes and distant from the ameloblastic-like cells.
CONCLUSIONS: There are at least two types of eosinophilic material in different areas within the tumor, one in the rosette and solid areas and another in lace-like areas. The secreted eosinophilic material in the rosettes and solid areas is probably a product of well-differentiated ameloblastic-like cells. It is positive for collagen I and negative for amelogenin, whereas some eosinophilic materials in the lace-like areas are positive for amelogenin. We hypothesize that the latter eosinophilic material could be a product of odontogenic cuboidal epithelial or intermediate stratum-like epithelial cells.

BACKGROUND: Adenoid ameloblastoma (AdAM) is a frequently recurrent tumor that shows hybrid histological features of both ameloblastoma and adenomatoid odontogenic tumor (AOT). AdAM is expected to be classified as a new subtype of ameloblastoma in the next revision of the World Health Organization (WHO) odontogenic tumor classification. However, whether AdAM is a histologic variant of ameloblastoma or AOT remains unclear. To establish a new category, genetic evidence indicating the tumor category is necessary.
METHODS: We present a case of a 23-year-old Japanese woman with AdAM who underwent genetic/DNA analysis for ameloblastoma-related mutation using immunohistochemical staining, Sanger sequencing, and next-generation sequencing (NGS) analyses with reliable clinicopathological evidence.
RESULTS: Immunohistochemical expression of BRAF p.V600E was diffusely positive for both ameloblastoma- and AOT-like components. Sanger sequencing and NGS analyses showed missense mutations in BRAF p.V600E (c.1799T > A), a gene that is commonly altered in ameloblastomas but not in KRAS, another gene associated with AOT.
CONCLUSIONS: This case report is the first to provide genetic evidence on the ameloblastomatous origin of AdAM with a BRAF p.V600E mutation. A larger series of AdAM groups\' molecular testing is needed to aptly classify them and prognosticate the best treatment.