Cystic ameloblastoma. A clinicopathologic analysis

Clinicopathologic Profile and Surgical Modalities in Mandibular Ameloblastoma: A Descriptive Study

BACKGROUND

Ameloblastoma is a benign neoplasm composed of epithelial tissue with invasive and infiltrative behavior at the local level and a high recurrence rate, with various histopathologic patterns and clinical forms. Approximately 85% of conventional ameloblastomas occur in the mandible, most often in the body, angle, and ascending ramus area. The treatment modalities include both conservative and radical treatments. Postoperative follow-up is most important in the treatment of ameloblastoma.

AIMS AND OBJECTIVES

To describe the clinicopathologic profile of mandibular ameloblastoma in patients undergoing different surgical modalities. The primary objective was to describe the clinicopathologic profile and surgical management of mandibular ameloblastoma in patients aged ≥18 years, who had reported to a tertiary dental care center for follow-up during the study period. The secondary objective was to describe the distribution of comorbidities associated with different surgical modalities and reconstructive methods.

SUBJECTS AND METHODS

A total of 34 patients with mandibular ameloblastoma who underwent various surgical modalities between 2011 and 2021 were studied. Information was collected using a predesigned proforma and statistically analyzed.

RESULTS

Thirty-four review cases of ameloblastoma were included in the study. The patients were analyzed concerning age, sex, site, size, clinical presentation, radiographic pattern, histopathologic subtype, type of surgery, and associated comorbidities. Most cases of mandibular ameloblastoma involve the age of 16 to 55 years. The mean age of occurrence was found to be 35.5±13.2. A female preponderance, a tumor size range of 2 to 4 cm, a multicystic variant, involvement of the mandibular body in the premolar-molar area, root resorption, cortical perforation, and a follicular type of histopathologic pattern were the common presentations. Isolated anterior tumors restricted to the incisor/canine region were not found. The common surgical modalities undertaken were conservative methods such as enucleation, and chemical cauterization, and radical methods such as marginal mandibulectomy and segmental resection. Reconstruction using a titanium plate or free fibular graft was performed in the indicated cases. The common comorbidities included difficulty in chewing and loss of facial contour. Recurrence after surgical treatment was rare. Only 9% of cases developed a recurrence within 5 years. No recurrence was noted in cases treated with radical treatment, whereas 50% of cases treated with conservative methods showed recurrence.

CONCLUSION

The age of occurrence, site, and size of the tumor, cortical perforation, root resorption, histopathologic type, and radiographic patterns are widely considered factors in devising a treatment plan for mandibular ameloblastoma. However, there may be rare instances where these tumors behave differently regardless of their innocuous clinicopathologic presentation. Surgical procedures such as segmental resection and marginal mandibulectomy were found to be promising for the eradication of the tumor, and prevention of recurrences and metastasis. However, conservative measures such as enucleation and chemical cauterization were fraught with an increased risk of tumor recurrence and metastasis. Future studies with a larger sample size should focus on the clinicopathologic characteristics of ameloblastoma to elucidate its varied behavior and develop newer and advanced treatment modalities that would provide better surgical and postsurgical outcomes in affected patients.

Analysis of the 100 most cited articles on ameloblastoma

OBJECTIVES

An increasing number of articles are published each year. The aim of this is to provide a list of the 100 most cited articles on the subject of ameloblastoma.

METHODS

A bibliographic search was performed on Google Scholar (GS), Microsoft Academic (MA), and Dimensions for ameloblastoma. A ranking was created in order of citation density. Graphical representations of keywords and authorship were created with VOSviewer. Statistical analysis was performed and only results with a 95% confidence interval were considered significant.

RESULTS

A helpful list of top 100 articles was developed to help professionals in a variety of ways. Some curiosities are discussed about this scientometric analysis in ameloblastoma articles.

CONCLUSIONS

A useful list of the top 100 most cited articles on ameloblastoma has been provided. Bibliometric and altmetric analysis using Google Scholar, Microsoft Academic, and Dimensions is a free and excellent tool, not only as a citation manager but also as a study reference.

Unicystic ameloblastoma of mural variant crossing the midline

Unicystic ameloblastoma (UCA) refers to cystic lesions that show gross features of a jaw cyst but on histologic examination show a typical ameloblastomatous epithelium lining part of the cyst cavity, with or without luminal and/or mural tumor growth. Even though the lesion is not as aggressive as the solid ameloblastoma, an accurate histopathologic diagnosis is essential for the treatment and prognosis. This case report illustrates a case of UCA of mural variant in the anterior region of the mandible crossing the midline, which is usually an unusual site of occurrence.

Ameloblastoma of the jaws in children: an evaluation of cases seen in a tertiary hospital in South-Eastern Nigeria

Background

Ameloblastoma is one of the most common benign odontogenic tumours in Nigeria. It is considered uncommon in children.

Materials and methods

This is a retrospective study of pediatric patients with histopathological diagnosis of ameloblastoma seen over seven years at the Oral and Maxillofacial Surgery Department of the University of Nigeria Teaching Hospital, Enugu, Nigeria. Relevant information was retrieved from patients' records and data obtained were analysed using SPSS version 23, the chi-square test was used to compare qualitative variables, a p-value of <0.05 was considered as significant.

Results

One hundred and thirty-six cases of ameloblastoma in all age groups were seen within the period. Thirty of the cases met the requirement. The mean age of the patients was 14.4 STD 2.03 (range from 10–17) years. Fourteen (46.7%) patients were male while 16 (53.3%) were female giving a ratio of 1:1.1. The duration of the lesion ranged from 3 months to 72 months (mean 15.07 months). Histologically, the follicular type (n=20, 66.7%) constitute the majority, while the clinical types were solid-multicystic (n=18, 60%) and unicystic (n=12, 40%). Enucleation was the treatment of choice in most (n=18, (60%)) of the patients.

Conclusion

Ameloblastoma is relatively uncommon in children, especially those less than ten years of age. The solid-multicystic variety was the predominant type in the children studied. Most patients presented long after the onset of the tumour and enucleation with mechanical curettage produced satisfactory results in these patients.

Funding

None declared

Recurrence Rates of Intraosseous Ameloblastoma Cases With Conservative or Aggressive Treatment: A Systematic Review and Meta-Analysis

Objective

This study aimed to systematically investigate and compare the post-treatment recurrence of intraosseous ameloblastoma in patients treated with conservative or aggressive approaches.

Methods

Systemic searches of PubMed, Medline, Cochrane Library, and Embase databases from inception to October 28, 2020, were conducted. Studies that aimed to evaluate the recurrence of intraosseous ameloblastoma by conservative and aggressive treatment approaches were included.

Results

A total of 20 studies with 942 ameloblastoma cases were included. Fourteen studies included patients with ameloblastoma who received conservative treatment, and 16 studies reported the overall recurrence rate for patients undergoing aggressive treatment. The pooled results indicated that the recurrence rate for aggressive treatment [0.12, 95% confidence interval (CI) = 0.09–0.16] was significantly lower than that for conservative treatment, with a recurrence rate of 0.30 (95% CI = 0.23–0.39). Similar results were obtained when stratifying the participants by the histological classification. When trying stratification analysis following the original included studies, multicystic ameloblastoma presented a much higher recurrence rate than solid and unicystic ameloblastomas.

Conclusion

These findings supported the hypothesis that aggressive treatment might lead to a lower recurrence rate than conservative treatment. More studies and meta-analyses following the new histological classification of ameloblastomas are needed to validate and support the findings.

Conceptual changes in ameloblastoma: Suggested re-classification of a "veteran" tumor

OBJECTIVES

The merging of ameloblastoma (AM) with mural unicystic ameloblastoma (UAM-M) was suggested by the 2017 WHO based on similar treatment needs. In an international multicenter study, we investigated the characteristics of their merged product (merged-AM) and raised the possibility of unifying AM and UAM (total-AM).

MATERIALS AND METHODS

AM and UAM (luminal/intraluminal/mural), separate and combined, were analyzed for demographic/clinical/radiological features. ANOVA and chi-square tests were followed by univariate and multivariate analyses, and significance was set at p < .05.

RESULTS

The patients' mean age was 39.6 ± 20.3 years in merged-AM (147 AM, 76 UAM-M), 45.1 ± 19.4 years in AM (p = .009). Merged-AM comprised 51.3% multilocular/48.7% unilocular tumors, AM comprised 72.5%/27.5%, respectively (p < .001). Merged-AM was associated with impacted teeth in 30.8%, AM in 18% (p = .023). The probability of merged-AM for multilocularity increased by 2.4% per year of age (95%CI 0.6-4.2, p = .009). Association with impacted teeth decreased by 7.9% per year of age (95%CI 1.9-14.39, p = .009). Merged-AM did not differ from total-AM (p > .05).

CONCLUSIONS

Merged-AM partially differed from AM, but differences appeared to diminish in an age/time-wise manner. Merged-AM and total-AM were nearly indistinguishable. Therefore, AM and UAM may be considered a continuous spectrum of one type of tumor, further necessitating revision of the treatment approaches.

Outcome of Mandibular Dentigerous Cysts 1 to 10 Years After Decompression Using a Custom-Made Appliance

PURPOSE

The aim of this study was to examine the long-term results of mandibular dentigerous cysts treated with decompression using a custom-made appliance.

PATIENTS AND METHODS

This retrospective study included 34 patients with dentigerous cysts who were treated as outpatients at the Faculty of Dentistry, Marmara University. Medical history, complaints, intraoral and extraoral clinical findings, treatment time, and complications of these patients were collected.

RESULTS

The average age of the patients was 7.94 years. Three tooth buds (canine, first permanent premolar [P1], and second permanent premolar) in 2 cases, two tooth buds in 7 cases (P1 and second permanent premolar in 6 cases and P1 and canine in 1 case), and one tooth bud in 25 cases were related to the cyst. The mean decompression time was 5.97 months (range, 3 to 9 months). No major complications occurred during or after decompression. No evidence of infection, breakdown and/or dehiscence of the soft tissue, or inferior alveolar nerve paresthesia was observed. The complications and complaints were minor and straightforward to resolve.

CONCLUSIONS

Decompression is a very effective and successful method for the treatment of mandibular dentigerous cysts.

Adjunctive Strategies for Benign Maxillofacial Pathology

Benign cysts and neoplasms of the maxillofacial region can vary in behavior, with some growing rapidly and resulting in destruction of surrounding structures. Despite their benign histology, many require often-morbid treatment to prevent recurrence of these lesions. Several less invasive and adjunctive medical treatments have been developed to lessen the morbidity of surgical treatment. As the molecular and genomic pathogenesis of these lesions is better understood, more directed treatments may lessen the burden for patients.

Radical vs conservative treatment of intraosseous ameloblastoma: Systematic review and meta-analysis

OBJECTIVES

The aim of the present study was to assess the outcomes of radical and conservative treatment approaches of solid/multicystic and unicystic ameloblastoma in terms of recurrence rates.

MATERIAL AND METHODS

A systematic review and meta-analysis was conducted based on the PRISMA statement. Search was performed using PubMed, Embase, SCOPUS, and Web of Science for articles published from January 1969 until March 2018. Quality assessment of the selected articles was conducted using the Quality Appraisal of Case Series Studies Checklist. The meta-analysis was performed using the MedCalc program.

RESULTS

The search strategy yielded 6,984 articles; 20 studies met the eligibility criteria and were included in the meta-analysis. The pooled recurrence rate of solid/multicystic ameloblastomas following radical treatment was 8%, while conservative treatment caused recurrences in 41%. For unicystic ameloblastomas, these values were 3% and 21%, respectively. The risk of recurrences in both types of ameloblastomas following radical treatment was lower than following conservative treatment.

CONCLUSIONS

The present study showed statistically significant differences in recurrence favoring radical treatment for both unicystic and solid/multicystic ameloblastoma. The solid/multicystic type showed more recurrences than the unicystic type. Unfortunately, since only retrospective studies were available, the evidence is less strong as wished for.

Ameloblastoma arising in the wall of dentigerous cyst: Report of a rare entity

Dentigerous cyst (DC) is a developmental odontogenic cyst that encloses the crown of an unerupted tooth by expansion of its follicle with accumulation of fluid between the reduced enamel epithelium and the tooth crown and is attached to the neck of the tooth. The lining of DCs shows a potential for neoplastic transformation to ameloblastoma, squamous cell carcinoma, and mucoepidermoid carcinoma. Here, we report a rare case of an ameloblastoma arising in the wall of a DC.

Pattern of distribution of odontogenic tumours in sub-Saharan Africa

OBJECTIVE

To analyse documented reports on odontogenic tumours (OTs) in sub-Saharan Black Africa and to create awareness of the need for more reports on this topic.

METHODS

There were 2,186 African cases of OTs presented at the International Association of Oral and Maxillofacial Pathologists (IAOP) Congress (Cape Town, South Africa) in 1998 that were added to 2,198 cases derived from reports published in the scientific literature from 1998 to date. The analysis undertaken included frequency distribution of available data on OTs that was listed in the 2005 World Health Organization (WHO) classification. The chi-square test was applied as appropriate.

RESULTS

A total of 4,384 cases of OTs from only 14 of 47 sub-Saharan Black African countries were analysed. Ameloblastoma was the OT most commonly reported, accounting for 74.2% of OTs (and 86.9% of category A OTs), followed by keratocystic odontogenic tumour (KCOT) (6.9%) and odontogenic myxoma (ODM) (4.9%). Malignant OTs were reported at a low frequency, of 1.4%. Nigeria contributed 38.7% of the cases of OT in this series.

CONCLUSIONS

Ameloblastoma is the commonest OT in sub-Saharan Africa and has a higher occurrence in male than in female subjects. With data on OTs not available from 33 of 47 sub-Saharan African countries, additional reports are needed.

Ameloblastoma Revisited

Ameloblastoma is a benign but locally aggressive neoplasm of the odontogenic epithelium, the treatment of which is controversial. A review was made of 22 patients treated for histologically diagnosed ameloblastoma between January 1975 and January 2000. We recorded data relating to patient sex, age, site of involvement, histologic type, surgical treatment, and number of recurrences. All ameloblastomas were located in the mandible. The most common histologic patterns were follicular and plexiform lesions. A total of 22.7% of the tumors were unicystic ameloblastomas. Unicystic lesions were seen to affect younger patients than the rest of the histologic types. Eighteen patients were initially treated in our center, and 4 cases were referred to our center for secondary treatment. The number of recurrences was significantly lower in patients initially treated in our center. Primary treatment comprised enucleation and bone curettage in 10 cases and radical surgery in 7. Forty percent of the unicystic lesions and 53.3% of the non-unicystic ameloblastomas of our study presented at least 1 recurrence. Ameloblastoma is a polymorphic neoplasm for which the treatment is conditioned by a number of clinical and histologic factors. An individualized preoperative study is essential for treatment.

Histopathological and Radiographic Analysis of Dental Follicle of Impacted Teeth Using Modified Gallego's Stain

INTRODUCTION

In the WHO classification of odontogenic tumours, hard tissue formation has been considered as a sub-classification however, this parameter has not been much explored in dental follicle in literature. Epithelial-mesenchymal interactions play an important role in odontogenesis and its associated pathologies; therefore research on dental follicle should also include mesenchymal components along with epithelial components. Additionally, special stains to identify the nature of such depositions in dental follicle have been less explored. Modified Gallego's stain is such an example which has not been tried in odontogenic lesions which makes this study unique.

AIM

Aim of this study was to study histopathological variations in dental follicle, the nature of calcification and depositions using Modified Gallego's stain and to correlate histological features of dental follicle with pericoronal width radiographically.

MATERIALS AND METHODS

A prospective histological study of the dental follicles of 50 impacted teeth was carried out to microscopically evaluate the dental follicular tissues for pathological changes, and to correlate it with pericoronal radiolucency. Impacted teeth with pericoronal radiographic width less than 3mm were included in the study and symptomatic teeth were excluded. Further Modified Gallego stain was used to differentiate the nature of hard tissue formation in dental follicle tissues.

RESULTS

Dental follicle histologically showed pathological changes resembling dentigerous cyst, ameloblastoma, odontogenic fibroma (Simple and WHO Type), clear cell odontogenic tumour, neurofibroma, neurilemmoma and mucoepidermoid carcinoma.

CONCLUSION

The dental follicle surrounding an impacted tooth has the potential to differentiate into a wide variety of tissue types, and thus shows the potential for cyst and tumour development which was observed in this study in most of the specimens with normal follicular width radiographically.

Rodríguez M, Liceága-Reyes R, Farfán-Morales JE, Aranda-Romo S, Molina-Frechero N, González-González R. Orosomucoid-1 Expression in Ameloblastoma Variants

Odontogenic tumors constitute a group of heterogeneous lesions of benign and malignant neoplasms with variable aggressiveness. Ameloblastomas are a group of benign but locally invasive neoplasms that occur in the jaws and are derived from epithelial elements of the tooth-forming apparatus. We previously described orosomucoid-1 protein expression in odontogenic myxomas. However, whether orosomucoid-1 is expressed in other odontogenic tumors remains unknown. Since orosomucoid-1 belongs to a group of acute-phase proteins and has many functions in health and disease, we identified and analyzed orosomucoid-1 expression in ameloblastoma variants and ameloblastic carcinoma using western blot and immunohistochemical techniques. Thirty cases of ameloblastoma were analyzed for orsomucoid-1; five specimens were fresh for western blot study (four benign ameloblastomas and one ameloblastic carcinoma), and 25 cases of benign ameloblastoma for immunohistochemical assays. Orosomucoid-1 was widely expressed in each tumor variant analyzed in this study, and differential orosomucoid-1 expression was observed between benign and malignant tumor. Orosomucoid-1 may play an important role in the behavior of ameloblastomas and influence the biology and development of the variants of this tumor.

Unicystic Ameloblastoma Presenting as a Multilocular Radiolucency in the Anterior Mandible: A Case Report

Ameloblastomas are tumors of odontogenic epithelial origin. The term unicystic ameloblastoma is used to describe cystic lesions with clinico-radiographic features resembling an odontogenic cyst, but histologically showing the presence of ameloblastomatous epithelium lining part of the cyst cavity. A large majority of lesions are found in the mandible, and usually cause a painless swelling of the jaws. They can be radiographically subdivided into 'dentigerous' and 'non-dentigerous' types. The unicystic ameloblastoma is believed to be less aggressive than a solid/multicystic ameloblastoma, and thus has a more favorable response to enucleation and curettage. This case report presents a case of unicystic ameloblastoma with a multilocular radiographic appearance in the anterior mandible of a 45-year-old female patient, along with a literature review of the topic.

Cytokeratin 14 and cytokeratin 18 expressions in reduced enamel epithelium and dentigerous cyst: Possible role in oncofetal transformation and histogenesis- of follicular type of adenomatoid odontogenic tumor

Introduction:

Odontogenic cysts and tumors arise from the structures and remnants associated with tooth development. Cysts and tumors derived from the odontogenic tissues constitute an unusually diverse group of lesions. This diversity reflects the complex development of the dental structures, since all these lesions originate through some alteration from the normal pattern of odontogenesis. Cytokeratin (CK) 14 is the typical intermediary filament of odontogenic epithelium, CK 18 is the major components of the intermediate filaments of simple or single layered epithelial tissue; it is not expressed in stratified squamous epithelium. The present study was undertaken to understand the expression pattern of these cytokeratins in dentigerous cyst, dental follicular tissue, adenomatoid odontogenic tumor (AOT) and unicystic ameloblastoma.

Materials and Methods:

The present study consists of 60 specimens consisting of 20 samples of Dentigerous cyst, 20 samples of Reduced enamel epithelium/dental follicles, 10 samples of Follicular type of AOT, 10 samples of unicystic ameloblastoma. The sections of these specimens were stained for CK 14 and CK 18. The number of cells positive for CK 14 and CK 18 was counted per 100 cells. The cells were counted in four randomly selected high-power fields and the mean was calculated. Scoring of cytokeratin 14 expressions was done using Remmele score.

Results:

The highest expression of cytokeratin 14 was noted in AOT, least was seen in dental follicle/Reduced enamel epithelium (REE). CK18 was negative in all the cases included in the present study.

Conclusion:

In the present study, the expression of CK14 was noted in AOT, Dentigerous cyst (DC), Unicystic Ameloblastoma (UCA) and Dental follicle/REE. The expressions between these lesions were compared. These expression pattern may provide an insight to the histogenesis of AOT.

Ameloblastoma in the Northeast region of Brazil: A review of 112 cases

Context:

Ameloblastomas are benign tumors of the jaws with locally invasive capacity.

Aim:

The aim of this study was to review 112 cases of ameloblastoma seen over an 18-year period (1992-2009) at the Pernambuco Dental School, University of Pernambuco and at Federal University of Sergipe, in the northeast region of Brazil.

Materials and Methods:

The following data were selected for analysis: age, gender, race, site distribution, radiographic appearance, association with an impacted tooth, size, presence of symptoms, clinicopathologic subtypes and recurrence.

Settings and Design:

In this retrospective study, Pearson's χ² test and t-test were employed. The critical level of significance was set at P < 0.05.

Results:

The mean age of the patients at presentation was 35.1 ± 16.8 years with a slight female preference. The peak prevalence was in the 11- to 20-year age group and declined with increasing age. Total 75 patients were black and 37 were white, for a 2:1 black: white ratio. The location of the ameloblastomas showed a marked predominance in the mandible (84.8%) and 69% of the cases presented with a multilocular radiographic appearance. The tumor was associated with an embedded tooth in 14 cases (12.7%): nine unilocular and five multilocular ameloblastomas. The maximum radiological extension of the lesions on panoramic radiographs was 0.5-20 cm (mean ± SD: 5.2 ± 3.3 cm) and most cases were symptom-free (75.9%). Solid/multicystic ameloblastoma was the most common clinicopathologic subtype. There was an association between the clinicopathologic subtypes and radiographic appearance (P < 0.001). Recurrence was observed in 13.3% of cases.

Conclusion:

We propose that racial factors may have strong influence on the incidence of ameloblastomas in the northeast region of Brazil, since most people have African descent. Data related to gender, location, radiographic appearance, size, symptoms, clinicopathologic subtypes and recurrence were similar to previous studies conducted in various parts of the world.

Plexiform unicystic ameloblastoma: a rare variant of ameloblastoma

The term plexiform unicystic ameloblastoma refers to a pattern of epithelial proliferation that has been described in cystic cavity. Because of unilocular presentation, it is commonly misdiagnosed as an odontogenic cyst. However, they may often behave clinically as biologically aggressive tumors. These tumors show high incidence of cortical perforation, tooth resorption and a high rate of recurrence after simple enucleation. This paper aims to provide an insight into this biologically distinct entity. A literature review on the topic has been added along with a case report highlighting the approach of diagnosis and management of such ameloblastomas.

Unicystic ameloblastoma arising from a residual cyst

Intraoral swellings involving alveolar ridges in edentulous patients are clinically diagnosed as residual cysts, traumatic bone cysts, Stafne's jaw bone cavity, ameloblastoma and metastatic tumours of the jaw. This case report describes a residual cyst in a 68-year-old edentulous male patient which was enucleated and histopathologically confirmed as a unicystic ameloblastoma.

Unicystic ameloblastoma arising from a residual cyst

Intraoral swellings involving alveolar ridges in edentulous patients are clinically diagnosed as residual cysts, traumatic bone cysts, Stafne's jaw bone cavity, ameloblastoma and metastatic tumours of the jaw. This case report describes a residual cyst in a 68-year-old edentulous male patient which was enucleated and histopathologically confirmed as a unicystic ameloblastoma.

Unicystic ameloblastoma of the mandible- report of two cases with review of literature

Ameloblastoma is classified into solid/multicystic, extraosseous/peripheral, desmoplastic and unicystic types based on the clinical appearance by WHO (2003). Unicystic ameloblastoma is the 2(nd) and far less frequent growth pattern seen in intra-osseous ameloblastoma. It tends to occur in younger population and constitutes approximately 6% of ameloblastomas with no sexual or racial predilection. Here in, reporting 2 cases of cystic ameloblastoma in the mandible, in varying age groups.

Ameloblastoma: A clinicoradiographic and histopathologic correlation of 11 cases seen in Goa during 2008-2012

Objectives:

The purpose of this case series was to compare the clinical, radiographic, and histopathologic features of 11 cases of ameloblastoma that reported to the Goa Dental College and Hospital over a period of 4 years from January 2008 to December 2012.

Study Design:

Data with respect to the patients’ ages, sex, location of lesions, radiographic features, histopathologic features and surgical treatment and follow-up, was analyzed.

Results:

The mean age in males was 23.25 ± 6.99 years, while that in females was 43.43 ± 17.13 years. Seven (63.63%) of the 11 subjects were females, and four (36.36%) were males. 10 (90.9%) of the 11 ameloblastomas were located in the mandible. Swelling was noted in all 11 patients. 10 cases showed radiographic findings, while one case was a peripheral soft-tissue variant. Seven (70%) of the 10 tumors were multilocular with a well-demarcated corticated border, and three cases (30%) were unilocular. Two cases showed a soap-bubble appearance. Histologically, five cases were unicystic, four were multicystic, one was desmoplastic and one was a peripheral variant. Follow-up ranged from 12 to 34 months and there were no signs of recurrence in any of the patients.

Conclusions:

Ameloblastomas more commonly occur in females at an older age, as compared with males. Radiographic features that could help in diagnosing ameloblastomas include its predominant occurrence in the mandible, multilocular radiolucency with well-defined, corticated, scalloped margins, expansion of buccal and lingual cortical plates, root resorption and tooth displacement.

Multilocular unicystic ameloblastoma of mandible

Introduction. We report a rare case of unicystic ameloblastoma (UA) of mandible which showed multilocular radiolucency on the left side of mandible on radiographic examination which is very unusual, and the majority of the cases of UAs till date has been reported of unilocular radiolucency. On histopathological examination, an odontogenic cystic lining that proliferates that intraluminally resembling ameloblastomatous epithelium was observed, leading to a definitive diagnosis of unicystic ameloblastoma. Case Presentation. A 42-year-old male patient presented with a swelling on the left side of the mandible extending from 33 to 36. Radiographically, it showed a multilocular radiolucent lesion resembling odontogenic cyst; however, the final diagnosis was made on histopathological ground with the inclusion of radiological and clinical features. Conclusion. It can be concluded that at present, histopathologic examination is the most sensitive tool for differentiating between odontogenic cysts and UAs. However, both clinical and radiologic findings share equal contribution to the final diagnosis.

Unicystic Ameloblastoma Masquerading as Huge Periapical Lesion, both Clinically and Histopathologically: Two Case Reports with Review of Literature

Unicystic ameloblastoma (UA) is one of the variants of ameloblastoma. It manifests as unilocular radiolucency in the mandible or maxilla on X-ray scans. In very rare cases, it can appear as a localized periradicular radiolucent area, imitating a periapical lesion. In this article, we present two cases of UA that were initially misdiagnosed as periapical lesions. Subsequently, surgical enucleation was performed and the diagnosis of UA was confirmed histopathologically.

An infected dentigerous cyst associated with an impacted permanent maxillary canine, inverted mesiodens and impacted supernumerary teeth

A dentigerous cyst is an odontogenic cyst associated with the crown of the impacted or unerupted teeth. Such cyst remain initially completely asymptomatic unless when infected and can be discovered only on routine radiographic examination. Here, such a case of dentigerous cyst, which was discovered on routine radiographic examination, is discussed here.

Unicystic mural ameloblastoma: an unusual case report

Ameloblastoma is a benign odontogenic neoplasm which frequently affects the mandible. The term ameloblastoma includes several clinicoradiological and histological types. Apart from the most commonly encountered clinicopathologic models, there are few variants, whose biological profile is unknown or not elicited. Among these types, unicystic ameloblastoma is the least encountered variant of the ameloblastoma. Unicystic ameloblastoma refers to those cystic lesions that show clinical, radiographic, or gross features of a jaw cyst but on histologic examination show a typical ameloblastomatous epithelium lining the cyst cavity, with or without luminal and/or mural tumor proliferation. Unicystic ameloblastoma is a less encountered variant of the ameloblastoma and is believed to be less aggressive. As this tumor shows considerable similarities with dentigerous cysts, both clinically and radiographically, the biologic behaviour of this tumor group was reviewed. Moreover, recurrence of unicystic ameloblastoma may be long delayed, and a long-term postoperative followup is essential for proper management of these patients. Here we are presenting a case of unicystic ameloblastoma in an 18-year-old female patient.

Graft necrosis occurred after iliac crest reconstruction after mandibular segmental resection of ameloblastoma

Ameloblastoma is an uncommon benign odontogenic neoplasm of the maxillofacial region constituting less than 1% of tumors of the oral cavity. Ameloblastomas have been categorized broadly into 3 biologic variants: cystic (unicystic), solid, and peripheral. Unicystic ameloblastoma is a rare and less aggressive variant of ameloblastoma. The aim of this report is to describe a case of cystic ameloblastoma treated with segmental resection and iliac graft reconstruction. The possible reasons of graft failure seen in our patient at the early stage of the healing were also discussed.

Trends in Pediatric Ameloblastoma and its Management: A 15 year Indian Experience

PURPOSE

The purpose of this study is to put forth our 15 year experience with pediatric ameloblastoma in the Indian population.

MATERIALS AND METHOD

This retrospective study was carried out in the pediatric group of 18 years and below, presenting with and diagnosed for ameloblastoma, at our institution over the past 15 years. The required data was collected by reviewing patient's case notes, relevant radiographs, histopathological reports, and treatment charts. The incidence of pediatric ameloblastomas with respect to age, sex, site of occurrence, histopathologic type, the type of treatment instituted, and recurrence rate was noted.

RESULTS

Of the total 165 pediatric tumors, ameloblastoma was the most common, 29 cases (17.5%). It occurred commonly in the age group of 12-18 years (mean age 14 years) with a marked male predilection. The most common site of occurrence was the posterior mandible. Majority were of the unicystic type. Two ameloblastomas which appeared as unilocular radiolucency were diagnosed as solid type. Twenty-eight were benign and one was a rare malignancy (Ameloblastic carcinosarcoma). Only two recurrences were noted over 15 years, of which one tumor interestingly recurred as a peripheral variety which responded well to local excision. Ameloblastomas were either enucleated with mechanical curettage or resected followed by primary reconstruction with either a reconstruction plate or free fibula flap.

CONCLUSION

We conclude that ameloblastomas are not uncommon in Indian pediatric population. Unilocular, unicystic ameloblastomas in the pediatric age group can be treated conservatively owing to their growth potential. Emphasis must be given to a long-term regular follow-up, conserving a more radical approach in case of a recurrence. However, Unilocular appearing ameloblastomas may be of the solid type which needs to be borne in mind as it not only alters the treatment modality but also emphasizes the importance of pre-operative incisional biopsy. Solid and unicystic aggressive ameloblastomas must be treated radically. Primary reconstruction with the free fibula flap is a viable option.

Unicystic ameloblastoma in 3 year old paediatric patient - A rare entity

Unicystic ameloblastoma (UA) is a benign epithelial odontogenic tumor of the jaws that commonly occurs in 2nd and 3rd decade of life. In fact, this entity is rare in children under 12 years of age. It is characterised as a distinct variant of ameloblastoma, exhibiting a less aggressive behaviour and a lower rate of recurrence than solid conventional ameloblastoma. There are very few reported cases of UA occurring in children below five years of age. The purpose of this case report is to describe a case of UA involving the crown of an unerupted maxillary second premolar in a 3 year old girl. The pathogenesis, clinical appearance, radiographic presentation, histological findings and management of the tumour have also been discussed.

Unicystic ameloblastoma of the mandible

Unicystic ameloblastoma refers to those cystic lesions that show clinical, radiographic or gross features of a jaw cyst but on histologic examination show a typical ameloblastomatous epithelium lining the cyst cavity, with or without luminal and/or mural tumor proliferation unicystic ameloblastoma is a less encountered variant of the ameloblastoma and believed to be less aggressive. As this tumor shows considerable similarities with dentigerous cysts, both clinically and radiographically the biologic behaviour of this tumor group was reviewed. Moreover, recurrence of unicystic ameloblastoma may be long delayed and a long-term post-operative follow up is essential for proper management of these patients. Here we are presenting a case of unicystic ameloblastoma in a 18 year old female patient.

An unusual case of unicystic intramural ameloblastoma and review of the literature

Ameloblastoma is the most common tumor of odontogenic origin. There are various types of this tumor and confusion still exists among the clinicians about the correct classification. Multicystic ameloblastoma is the most frequent subtype while unicystic ameloblastoma can be considered as a variant of the solid or multycistic. This subtype is considered as a less aggressive tumor with a variable recurrence rate. However, its frequency is often underestimated. The aim of this article is reviewing the recent literature about unicystic ameloblastoma using our unusual clinical case as a starting point to illustrate this discussion. A 30-year-old man who had been complaining of slight pain in the premolar and molar area of the left side of mandible had a check up at our department. X-rays revealed a unilocular radiotrasparency with radiopaque margins. The first histological diagnosis was an odontogenic cyst. Successive histological evaluations revealed that ameloblastic epithelial islands were present in lassus connective tissue. We think that our case report provides new insights into the approach to the ameloblastoma diagnosis. We agree with authors who have pointed out that a single small biopsy may often be inadequate for the correct diagnosis of amelobastoma. Moreover, in the light of our experience, it should be kept in mind that ameloblastomas may have sometimes unusual presentations and this fact should induce surgeons and pathologists to consider carefully each lesion.

Unicystic ameloblastoma: A diagnostic dilemma

Ameloblastoma is a slow-growing, persistent and locally aggressive neoplasm of epithelial origin accounting for 10% out of 30% of all odontogenic tumors. According to the World Health Organization, ameloblastomas are classified into the following types: conventional, unicystic, and peripheral. Unicystic ameloblastoma (UA) refers to those cystic lesions that show clinical, radiographic, or gross features of a mandibular cyst, but on histologic examination show a typical ameloblastomatous epithelium lining part of the cyst cavity, with or without luminal and/or mural tumor growth. We report a case of young female with a radiolucent lesion in the right posterior mandible. Surgical removal of the lesion was performed, with differential diagnosis of a radicular cyst. However, histopathologic examination revealed UA. The patient was kept under observation and showed signs of local bone regeneration. The purpose of presenting this report of a clinical case of UA previously misdiagnosed as radicular cyst is to emphasize the significance of histopathologic examination of all tissue specimens recovered in surgery even when clinical and radiological finding are innocuous.

Maxillary unicystic ameloblastoma: A review of the literature

The term unicystic ameloblastoma (UA) refers to those cystic lesions that show clinical, radiographic, or gross features of a jaw cyst, but on histologic examination show a typical ameloblastomatous epithelium lining part of the cyst cavity, with or without luminal and/or mural tumor growth. Although the histology suggests that cystic ameloblastomas follow a biologically low-grade course, recent evidence suggests that they may often behave clinically as aggressive tumors. This is supported by the high incidence of cortical perforation, tooth resorption, increase in lesion size, bony destruction, and a high rate of recurrence after simple enucleation. Here, the authors present a case report on unicystic variant of ameloblastoma in the maxilla. An attempt has been made to emphasize that it can involve the maxillary jaw, which is rarely affected and could be more aggressive than previously thought. A literature review on the topic has been added along with the case report. It is important to remember that a proper and timely diagnosis of the character and extent of a UA (with a thorough histopathologic examination of the entire specimen) can help in the overall long-term well-being of the patient.

Plexiform ameloblastoma

The ameloblastoma is a benign but aggressive neoplasm of odontogenic origin. However, no enamel or hard tissue is formed by the tumor cells. Ameloblastomas are infamous for their invasive growth and their tendency to recur. Robinson (1937) as a benign tumor that is ‘usually unicentric, nonfunctional, intermittent in growth, anatomically benign and clinically persistent.’ They may occur at any age, even though nearly half of the tumors do occur between the ages of 20 and 40 years. This is the most common neoplasm affecting the jaws, yet only accounts for 1% of all tumors of the maxilla and mandible and 11% of all odontogenic tumors.

This report presents a case of ameloblastoma involving entire ramus and part of body of mandible with resorption of the mesial and distal root apices of second molar and distal root of mandibular first molar. The lesion extending till the base of mandible surrounding the crown of the unerupted third molar resembling the dentigerous cyst. This was surgically resected followed by harvesting the contralateral sixth costochondral rib graft.

How to cite this article: Celur S, Babu KS. Plexiform Ameloblastoma. Int J Clin Pediatr Dent 2012;5(1):78-83.

Unicystic ameloblastoma with diverse mural proliferation - a hybrid lesion

A 46-year-old man was referred to our hospital for treatment, complaining of swelling on the right mandibular molar region. Radiographic examination revealed a well defined multilocular radiolucent lesion with root resorption of right lower anteriors and molars. Following biopsy, a diagnosis of unicystic ameloblastoma of mural type was made and hemimandibulectomy was performed under general anesthesia. Histopathological examination of the surgical specimen exhibited a unicystic ameloblastoma of luminal, intraluminal, and mural type. Intraluminal proliferation was of plexiform pattern and mural proliferation showed unusual histopathological findings, which revealed follicular, acanthomatous areas coexisted with desmoplastic areas. This mural picture was similar to the so-called 'hybrid lesion of ameloblastoma', whose biological profile is not elicited due to the lack of adequate published reports. Two years follow up till date has not revealed any signs of recurrence.