Dentigerous cysts suspected the other odontogenic lesions on panoramic radiography and CT

Dentigerous cysts are known as the second most common type of cyst in the jaws. The cyst is one of the lesions occurred frequently in the posterior body of the mandible and is often related to the unerupted third molar and forms around the crown of the unerupted tooth attaching at the cementoenamel junction. Such characteristic appearances are the diagnostic points differentiating from ameloblastoma or odontogenic keratocyst. However, it would be hard for us to diagnose it as a dentigerous cyst if the lesion does not show its typical appearance. We experienced two cases of dentigerous cysts which did not form around the crown of the unerupted tooth on radiologically. Both cysts were relatively large and resorbed adjacent teeth roots. Therefore, an ameloblastoma or an odontogenic keratocyst was suspected rather than a dentigerous cyst as the imaging diagnosis. The biopsy revealed that the lesion was a "dentigerous cyst" in one of the cases and "developmental cyst with inflammation" in another case. After the excision, the histopathological diagnosis was a dentigerous cyst with inflammation in both cases. This report shows the two cases of dentigerous cysts focusing on panoramic radiography and CT images. Also, we discuss the differential diagnosis by reconsidering those diagnostic points.

Peripheral ameloblastoma underlying squamous cell papilloma after a third molar extraction

Peripheral ameloblastoma (PA) is a rare variant of ameloblastoma that presents as a slow-growing, painless mass in the gingival tissues or alveolar mucosa. It shares histologic features with conventional ameloblastoma but is less invasive and aggressive. This case report describes a 51-year-old female with a PA that simultaneously or subsequently developed underlying squamous cell papilloma after mandibular third molar extraction. Clinical examination revealed a pedunculated gingival lesion mimicking squamous cell papilloma. Histopathologic examination confirmed PA underlying squamous cell papilloma after an excisional biopsy. Imaging revealed mild bone resorption, leading to a further soft tissue excision and minimal osteoectomy to rule out intraosseous involvement. The patient remained asymptomatic without signs of recurrence in the 1-year follow-up. PA diagnosis can be challenging due to its clinical resemblance to other gingival lesions and histopathologic features. Treatment typically involves surgical excision, with long-term follow-up recommended due to possible recurrence and malignant transformation.

Automatic segmentation of ameloblastoma on ct images using deep learning with limited data

BACKGROUND

Ameloblastoma, a common benign tumor found in the jaw bone, necessitates accurate localization and segmentation for effective diagnosis and treatment. However, the traditional manual segmentation method is plagued with inefficiencies and drawbacks. Hence, the implementation of an AI-based automatic segmentation approach is crucial to enhance clinical diagnosis and treatment procedures.

METHODS

We collected CT images from 79 patients diagnosed with ameloblastoma and employed a deep learning neural network model for training and testing purposes. Specifically, we utilized the Mask R-CNN neural network structure and implemented image preprocessing and enhancement techniques. During the testing phase, cross-validation methods were employed for evaluation, and the experimental results were verified using an external validation set. Finally, we obtained an additional dataset comprising 200 CT images of ameloblastoma from a different dental center to evaluate the model's generalization performance.

RESULTS

During extensive testing and evaluation, our model successfully demonstrated the capability to automatically segment ameloblastoma. The DICE index achieved an impressive value of 0.874. Moreover, when the IoU threshold ranged from 0.5 to 0.95, the model's AP was 0.741. For a specific IoU threshold of 0.5, the model achieved an AP of 0.914, and for another IoU threshold of 0.75, the AP was 0.826. Our validation using external data confirms the model's strong generalization performance.

CONCLUSION

In this study, we successfully applied a neural network model based on deep learning that effectively performs automatic segmentation of ameloblastoma. The proposed method offers notable advantages in terms of efficiency, accuracy, and speed, rendering it a promising tool for clinical diagnosis and treatment.

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.

Clinical outcome following conservative treatment of 58 mandibular ameloblastoma patients: a retrospective study

The aim of this study was to retrospectively analyze the surgical outcome of the patients with mandibular ameloblastoma (MA) with intact inferior cortex and the lingual cortex of the mandible, treated with conservative management in the form of enucleation with peripheral ostectomy, mechanical curettage, chemical cauterization, dredging, and marsupialization. The patients were included with the diagnosis of MA between the age group of 14 to 60 years with their computed tomography (CT) scans showing intact inferior cortex and the lingual cortex of the mandibular walls. Out of 96 cases of ameloblastoma, 58 (61%) were in mandible and 38 (39%) cases in maxilla. We analyzed these 58 patients retrospectively which were operated conservatively between January 2009 and December 2018. The treatment protocol for all the solid variants and the unicystic variants with intact buccal, inferior, and the lingual cortex was enucleation with peripheral ostectomy followed by mechanical curettage, chemical cauterization, and subsequent dredging. This was performed in 90% (n = 52) cases, whereas the treatment protocol for unicystic variants with perforated buccal cortex and intact inferior and lingual cortex was marsupialization followed by the enucleation with peripheral ostectomy, mechanical curettage, chemical cauterization, and subsequent dredging which was performed in 10% (n = 6) cases. Chi square test was applied to the effectiveness of conservative management as outcome variable. The new bone formation along with bony trabeculae was found in 96.6% (n = 56) of the cases. Recurrence was noted in 3.44% (n = 2) of the cases. A p value was 0.001, thus suggesting statistically highly significant result. On the basis of present study, though we can conclude that the MA with the intact inferior and the lingual cortex can be managed effectively with conservative treatment with long term regular follow up, still we would caution that the reader must use their best clinical judgement based on latest available data. For some patients, returning to clinic frequently and undergoing multiple minor procedures may not be suitable to be considered the best, whereas resection and reconstruction may be deemed more appropriate.

Deep learning applied to the histopathological diagnosis of ameloblastomas and ameloblastic carcinomas

BACKGROUND

Odontogenic tumors (OT) are composed of heterogeneous lesions, which can be benign or malignant, with different behavior and histology. Within this classification, ameloblastoma and ameloblastic carcinoma (AC) represent a diagnostic challenge in daily histopathological practice due to their similar characteristics and the limitations that incisional biopsies represent. From these premises, we wanted to test the usefulness of models based on artificial intelligence (AI) in the field of oral and maxillofacial pathology for differential diagnosis. The main advantages of integrating Machine Learning (ML) with microscopic and radiographic imaging is the ability to significantly reduce intra-and inter observer variability and improve diagnostic objectivity and reproducibility.

METHODS

Thirty Digitized slides were collected from different diagnostic centers of oral pathology in Brazil. After performing manual annotation in the region of interest, the images were segmented and fragmented into small patches. In the supervised learning methodology for image classification, three models (ResNet50, DenseNet, and VGG16) were focus of investigation to provide the probability of an image being classified as class0 (i.e., ameloblastoma) or class1 (i.e., Ameloblastic carcinoma).

RESULTS

The training and validation metrics did not show convergence, characterizing overfitting. However, the test results were satisfactory, with an average for ResNet50 of 0.75, 0.71, 0.84, 0.65, and 0.77 for accuracy, precision, sensitivity, specificity, and F1-score, respectively.

CONCLUSIONS

The models demonstrated a strong potential of learning, but lack of generalization ability. The models learn fast, reaching a training accuracy of 98%. The evaluation process showed instability in validation; however, acceptable performance in the testing process, which may be due to the small data set. This first investigation opens an opportunity for expanding collaboration to incorporate more complementary data; as well as, developing and evaluating new alternative models.

Dentinogenic ghost cell tumor associated with odontoma: report of a rare case and review of literature

Dentinogenic ghost cell tumor (DGCT) is an uncommon odontogenic tumor considered to be the solid, tumorous variant of calcifying odontogenic cyst. DGCT is characterized by islands of ameloblastoma-like epithelial cells that resemble the enamel organ, the presence of ghost cells, and dentinoid material. This article reports a rare case of dentinogenic ghost cell tumor associated with an odontoma in an adult patient, with a review of the literature. To the best of the authors' knowledge, there have only been four case reports of DGCT associated with odontoma, all of which occurred in children and adults younger than 30 years old.

[Cone-beam CT imaging features of common cystic lesions associated with the impacted mandibular third molar]

Objective: To analyze the imaging features of cone-beam CT (CBCT) of ameloblastoma (AB), odontogenic keratocyst (OKC) and dentigerous cysts (DC) associated with the mandibular impacted third molars,so as to provide useful information for differential diagnosis of these lesions. Methods: The patients who were with complete clinical data, pathological diagnosis and CBCT images from AB, OKC and DC around the mandibular impacted third molars were collected in Peking University Hospital of Stomatology from August 2016 to December 2021. A total of 109 patients (14 were diagnosed as AB, 23 were diagnosed as OKC and the others were diagnosed as dental cysts) were collected, including 73 males and 36 females. The age ranged from 11 to 70. The analyzed imaging features included location and internal density of the lesions, bone expansion, root resorption of adjacent teeth and types of the impacted teeth. The Chi square test was used to compare the gender of different lesions, and the Fisher's exact test was used to compare imaging features of lesions. When P<0.05, there was a significant difference among the three. Logistic regression analysis was performed to determine the imaging features that significantly contribute to correct imaging diagnosis. Corresponding P-values were calculated for all factors from multivariate models. Results: In the 23 cases of OKC, no special location was observed for the center of the lesion, heterogeneous high-density were seen in 21.7% of the cases, 56.5% of the cases had no significant bone expansion and the impacted teeth were not specially oriented. Among the 14 AB, 7 cases (7/14) were mainly located in the ramus of the mandible, and all cases (14/14) had buccal/lingual expansion of the jaw, 8 cases (8/14) presented root resorption of the adjacent teeth, and mesial impacted mandibular third molar were seen in 6 cases (6/14). Among the 72 DC, 88.9% (64/72) of the cases were mainly limited to the crown of the impacted third molar, 72.2% (52/72) of the cases had no obvious bone expansion, inverted impacted teeth were shown in 56.9% (41/72) of the cases. There was a significant difference among the three groups (χ2=7.30, P=0.026) in gender. AB and odontogenic cyst were more common in men than in women, while the incidence of OKC was roughly equal between men and women.There were significant differences in the location (P<0.001), internal density (P=0.001) of the lesions, bone expansion (P<0.001) and types of the impacted teeth (P<0.001), while no statistical difference was found for root resorption of adjacent teeth (P=0.153). Logistics regression analysis showed that the location of the lesion, internal density, bone expansion, root resorption of adjacent teeth and the types of impacted teeth had significant effects on the accurate diagnosis of the three kinds of lesions. Conclusions: Location, internal density, bone expansion and types of the impacted teeth played an important role in the correct imaging diagnosis. Further analysis indicates that when the classification of impacted teeth and the location of lesions are considered synchronously, DC can be differentiated from AB and OKC.

Machine learning-based radiomics for predicting BRAF-V600E mutations in ameloblastoma

Background

Ameloblastoma is a locally invasive and aggressive epithelial odontogenic neoplasm. The BRAF-V600E gene mutation is a prevalent genetic alteration found in this tumor and is considered to have a crucial role in its pathogenesis. The objective of this study is to develop and validate a radiomics-based machine learning method for the identification of BRAF-V600E gene mutations in ameloblastoma patients.

Methods

In this retrospective study, data from 103 patients diagnosed with ameloblastoma who underwent BRAF-V600E mutation testing were collected. Of these patients, 72 were included in the training cohort, while 31 were included in the validation cohort. To address class imbalance, synthetic minority over-sampling technique (SMOTE) is applied in our study. Radiomics features were extracted from preprocessed CT images, and the most relevant features, including both radiomics and clinical data, were selected for analysis. Machine learning methods were utilized to construct models. The performance of these models in distinguishing between patients with and without BRAF-V600E gene mutations was evaluated using the receiver operating characteristic (ROC) curve.

Results

When the analysis was based on radiomics signature, Random Forest performed better than the others, with the area under the ROC curve (AUC) of 0.87 (95%CI, 0.68-1.00). The performance of XGBoost model is slightly lower than that of Random Forest, and its AUC is 0.83 (95% CI, 0.60-1.00). The nomogram evident that among younger women, the affected region primarily lies within the mandible, and patients with larger tumor diameters exhibit a heightened risk. Additionally, patients with higher radiomics signature scores are more susceptible to the BRAF-V600E gene mutations.

Conclusions

Our study presents a comprehensive radiomics-based machine learning model using five different methods to accurately detect BRAF-V600E gene mutations in patients diagnosed with ameloblastoma. The Random Forest model's high predictive performance, with AUC of 0.87, demonstrates its potential for facilitating a convenient and cost-effective way of identifying patients with the mutation without the need for invasive tumor sampling for molecular testing. This non-invasive approach has the potential to guide preoperative or postoperative drug treatment for affected individuals, thereby improving outcomes.

A RARE CASE OF PERIPHERAL ADENOID AMELOBLASTOMA WITH DENTINOID

Adenoid ameloblastoma with dentinoid (AAD) is an extremely rare central neoplasm of the gnathic bones with no reported case of peripheral AAD. Adenoid ameloblastoma with dentinoid was first reported by Slabbert et al. in 1992 under the term "dentinoameloblastoma." However, the Armed Forces Institute of Pathology introduced the name "adenoid ameloblastoma with dentinoid" in 1994. Histologically, AAD shows features of ameloblastoma and adenomatoid odontogenic tumor along with a calcified product resembling dentin. The biological behavior of central AAD is not well established, though, in the literature, several reports consider it to be among the more aggressive odontogenic neoplasms, with a propensity for local invasion and recurrence. The demographic characteristics, clinical features, behavior, and prognosis of the peripheral AAD (PAAD) are unknown. To the best of our knowledge, this is the first reported case of PAAD in a 62-year-old woman.

Potential role of active decompression and distraction sugosteogenesis for the management of ameloblastomas: Report of two cases and review of the literature

Ameloblastomas are aggressive odontogenic entities well-known for their high tendency to recur. Clinical presentation includes lesions discovered on routine examination or radiographs, pathologies causing facial swelling, pain, cortical expansion, tooth mobility, root resorption, and paresthesia. Radiographic findings comprise large unilocular or multilocular radiolucencies with well-defined borders associated to an impacted tooth. Ameloblastomas are classified as unicystic, multicystic/solid, and peripheral. Treatment options include marsupialization, decompression, enucleation, or curettage with or without adjuvant measures such as Carnoy's solution, marginal resection, and segmental resection. Recently, active decompression with distraction sugosteogenesis (ADDS) was introduced for the conservative management of odontogenic cystic conditions. The purpose of this paper is to present 2 cases of a conventional ameloblastoma treated by means of ADDS. The purpose of this novel approach is to significantly reduce the amount of time required to decompress cystic-like lesions. In these cases, ADDS proved to be a viable treatment because it demonstrated a reduction in size of the initial lesion by new osseous formation within 2 weeks of placement of the device. The cases presented in this paper demonstrate that ADDS could be a valuable treatment modality for this type of ameloblastoma, although further research is necessary to validate this philosophy.

[Treatment of maxillary ameloblastoma with different modalities: a retrospective analysis of 92 cases]

PURPOSE

To explore the appropriate surgical approach for each type of maxillary ameloblastoma.

METHODS

The clinical data of 92 patients with maxillary ameloblastoma were retrospectively analyzed. All patients were pathologically diagnosed, followed up for 3-8 years after surgery, maxillofacial CT and panoramic images were taken regularly to observe the surgical outcomes. SPSS 22.0 software package was used for data analysis.

RESULTS

The proportion of maxillary ameloblastoma in male and female patients was 3 to 1,with more male patients and the mean age was 45.77 years old. The total recurrence rate of 92 patients was 21.74%, among which unicystic ameloblastoma had no recurrence after different surgical procedures. Among 38 patients with typical maxillary ameloblastoma, 14 underwent curettage, 3 underwent decompression，16 underwent extended resection, 3 underwent subtotal maxillary resection, 1 underwent iliac bone transplantation after subtotal maxillary resection, and 1 underwent reconstruction with anterolateral thigh flap after subtotal maxillary resection. Among them, 18 had recurrence and 5 had canceration. Three patients with extrasseous/peripheral type underwent expanded resection and two underwent curettage，none of them had recurrence. One patient with metastasizing ameloblastoma recurred after extended resection.

CONCLUSIONS

Maxillary ameloblastoma with unicystic type should be completely removed with minimal trauma. The recurrence rate of maxillary ameloblastoma via simple curettage or extended resection is still relatively high, which may be due to the large tumor involvement scope of these patients and the failure of complete tumor removal by curettage. For external/peripheral ameloblastoma and metastatic ameloblastoma, the involved jaw bone should be removed as much as possible to prevent recurrence. For malignant transformation of ameloblastoma, the tumor and jaw bone should be dissected during the operation to reduce recurrence rate. The primary site, cervical lymph nodes and lungs should be closely followed after operation to detect early metastasis.

Innocuous presentation of ameloblastic carcinoma

Ameloblastic carcinoma is a rare malignant odontogenic neoplasm that exhibits diverse clinical and radiological presentations. In fact there are several differential diagnoses during histopathological evaluation too. Lack of adequate reports could not establish the predominant demographic, clinical and radiological presentations. For the same reasons, the role of adjuvant radiotherapy and chemotherapy is also unsubstantiated yet. This case discusses the innocuous clinical and radiological presentation of ameloblastic carcinoma in a 55-year-old man where the diagnostic confirmation was achieved through histopathological evaluation. The differential diagnoses, treatment and follow-up details of this case are discussed in light of the previous published case reports and systematic reviews of case reports in an attempt to increase the sensitisation among dentists towards ameloblastic carcinoma.

[CLINICAL AND RADIOLOGICAL CHARAKTERISTICS OF AMELOBLASTOMAS OF JAWS AND THEIR DIFFERENTIAL DIAGNOSIS]

The purpose of the study is to examine the clinical radiological features of the amtereloblastomas through a comprehensive survey of patients and assess the possibility of conducting differential diagnosis based on the data obtained.Under our observation there were 267 patients with benign tumors of the upper and lower jaws, which were carried out with a clinical examination and surgical treatment with subsequent histological examination of the material. An analysis of the clinical symptoms of ameloblastomas was carried out, the X-ray systematization of cystic forms of this tumor was proposed.The use of a comprehensive clinical examination of patients with tumors and tumor-like formations of jaws (computed tomography, radiological and ultrasound methods of examination) makes it possible to increase the accuracy during their differential diagnosis.

Computer tomographic differential diagnosis of ameloblastoma and odontogenic keratocyst: classification using a convolutional neural network

OBJECTIVE

To analyse the automatic classification performance of a convolutional neural network (CNN), Google Inception v3, using tomographic images of odontogenic keratocysts (OKCs) and ameloblastomas (AMs).

METHODS

For construction of the database, we selected axial multidetector CT images from patients with confirmed AM (n = 22) and OKC (n = 18) based on a conclusive histopathological report. The images (n = 350) were segmented manually and data augmentation algorithms were applied, totalling 2500 images. The k-fold × five cross-validation method (k = 2) was used to estimate the accuracy of the CNN model.

RESULTS

The accuracy and standard deviation (%) of cross-validation for the five iterations performed were 90.16 ± 0.95, 91.37 ± 0.57, 91.62 ± 0.19, 92.48 ± 0.16 and 91.21 ± 0.87, respectively. A higher error rate was observed for the classification of AM images.

CONCLUSION

This study demonstrated a high classification accuracy of Google Inception v3 for tomographic images of OKCs and AMs. However, AMs images presented the higher error rate.

The epidemiology and management of ameloblastomas: A European multicenter study

The present study aimed at assessing the epidemiology including demographic variables, diagnostic features, and management of ameloblastomas at several European departments of maxillofacial and oral surgery. The following data were recorded for each patient: gender, age, voluptuary habits, comorbidities, site, size, radiographic features, type, histopathological features, kind of treatment, length of hospital stay, complications, recurrence, management and complications of the recurrence. A total of 244 patients, 134 males and 110 females with ameloblastomas were included in the study. Mean age was 47.4 years. In all, 81% of lesions were found in the mandible, whereas 19% were found in the maxilla. Mean size of included ameloblastomas was 38.9 mm. The most frequently performed treatment option was enucleation plus curettage/peripheral ostectomy in 94 ameloblastomas, followed by segmental resection (60 patients), simple enucleation (46 patients), and marginal resection (40 patients). A recurrence (with a mean follow up of 5 years) was observed in 47 cases out of 244 ameloblastomas (19.3%). Segmental resection was associated with a low risk of recurrence (p = 0003), whereas enucleation plus curettage/peripheral ostectomy was associated with a high risk of recurrence (p = 0002). A multilocular radiographic appearance was associated with a high risk of recurrence (p < .05), as well as the benign solid/multicystic histologic type (p < .05). Within the limitations of the study it seems that the management of ameloblastomas will probably remain controversial even in the future. Balancing low surgical morbidity with a low recurrence rate is a difficult aim to reach.

A possible case of ameloblastoma in an adult male from the early 20th century Coimbra, Portugal

OBJECTIVE

This article discusses the differential diagnosis of an unusual lesion found in the mandible of an adult male individual (late 19th to early 20th century).

MATERIALS

A cranium from the Identified Skulls Collection Escolas Médicas of the University of Coimbra, Portugal.

METHODS

Macroscopic analysis, conventional radiography.

RESULTS

Macroscopically, a conspicuous osteolytic lesion was identified in the middle vestibular area of the mandible. The conventional radiography examination revealed a multilocular and non-expansive lesion, with undefined contours and irregular walls.

CONCLUSIONS

These characteristics are compatible with a benign lesion, possibly an ameloblastoma or an odontogenic keratocyst.

SIGNIFICANCE

The present work contributes substantially to the knowledge of the development of cystic and tumour lesions in the past and generates a broader body of knowledge about these lesions.

LIMITATIONS

Destructive methods were not authorized.

SUGGESTIONS FOR FURTHER RESEARCH

In the future, computed tomography scans and 3D reconstruction analysis, not performed in the current study, may add new and valuable information.

Deep learning neural networks to differentiate Stafne's bone cavity from pathological radiolucent lesions of the mandible in heterogeneous panoramic radiography

This study aimed to develop a high-performance deep learning algorithm to differentiate Stafne’s bone cavity (SBC) from cysts and tumors of the jaw based on images acquired from various panoramic radiographic systems. Data sets included 176 Stafne’s bone cavities and 282 odontogenic cysts and tumors of the mandible (98 dentigerous cysts, 91 odontogenic keratocysts, and 93 ameloblastomas) that required surgical removal. Panoramic radiographs were obtained using three different imaging systems. The trained model showed 99.25% accuracy, 98.08% sensitivity, and 100% specificity for SBC classification and resulted in one misclassified SBC case. The algorithm was approved to recognize the typical imaging features of SBC in panoramic radiography regardless of the imaging system when traced back with Grad-Cam and Guided Grad-Cam methods. The deep learning model for SBC differentiating from odontogenic cysts and tumors showed high performance with images obtained from multiple panoramic systems. The present algorithm is expected to be a useful tool for clinicians, as it diagnoses SBCs in panoramic radiography to prevent unnecessary examinations for patients. Additionally, it would provide support for clinicians to determine further examinations or referrals to surgeons for cases where even experts are unsure of diagnosis using panoramic radiography alone.

Fibula osteal flap with proximal peroneal perforator skin paddle for composite oromandibular reconstruction: A case report

RATIONALE

Cutaneous perforators of peroneal vessels are divided into proximal and distal perforators on the basis of perforator distributions and musculocutaneous or septocutaneous properties. The traditional fibular osteocutaneous free flap is raised over the distal two-thirds of the fibula with a skin paddle based on distal perforators, which is affixed to the posterior crural septum. However, the skin pedicle may not be available due to anatomic variations or intraoperative injuries. Herein, because of the absence of distal perforators, we reserved and expropriated proximal perforators originating from the musculocutaneous branch of the superior part of the peroneal artery before it divided into nutrient and arcuate arteries and successfully harvested a separate osteal fibula and proximal perforator skin paddle with a single vascular pedicle-peroneal vessel.

PATIENT CONCERNS

A 62-year-old man with a 6-month history of mandibular swelling and soft tissue invasion was referred to us.

DIAGNOSIS

Panoramic radiography and computed tomography showed an irregular radiolucent lesion of the mandibular body, and histopathological analysis confirmed a follicular-pattern ameloblastoma.

INTERVENTIONS

The diseased mandible and soft tissue were resected and reconstructed with a vascularized fibular osteal flap with the proximal perforator skin paddle.

OUTCOMES

The mandibular contour was successfully restored; the skin paddle in the mouth was in good condition after 8 months of follow-up.

LESSONS

The proximal perforator is reliable and practical for supplying a skin paddle and has significant potential for future applications. We recommend reserving the proximal perforator skin paddle as a backup flap when planning to raise a fibula flap, since unavailability or injury of the traditional fibular skin island based on distal perforators occurs frequently. This approach can avoid the exploration for a second donor site, save surgical time, and reduce surgical complexity. Moreover, we anticipate more frequent use of the proximal perforator flap in the future because of its flexibility and large volume, and since it can be combined with the osteal fibula or fibular osteocutaneous flap. However, an understanding of the traits of the proximal perforator and determination of its peroneal origin by computed tomography angiography is crucial for predesigning fibular osteal flaps with a proximal perforator skin paddle.

Application of optimized digital surgical guides in mandibular resection and reconstruction with vascularized fibula flaps: Two case reports

RATIONALE

Currently, digital surgical techniques have been widely used in the precise treatment of mandibular resection and reconstruction with fibula flaps. Utilizing these innovative techniques in surgical planning and hardware fabrication before surgery has shown to provide great help. However, it is difficult for even experienced surgeons to place the preformed reconstruction plate in the same position as its preoperative design, causing surgical results to differ from preoperative planning. This study aims to solve these acknowledged challenges by creating newly designed equipment.

PATIENT CONCERNS

Two patients suffering from long-term expansion of the mandible were admitted to our department. Case I was a 39-year-old female patient who was concerned about the disease in the middle of the mandible, Case II was a 45-year-old female patient who was concerned about the disease at the left mandibular angle and ramus region.

DIAGNOSES

Two patients were diagnosed with the mandibular ameloblastoma based on computed tomography (CT) scan and pathological results.

INTERVENTIONS

Personalized 3-dimensional (3D) surgical guides were applied to 2 patients with mandibular ameloblastoma who underwent mandibular resection and reconstruction with vascularized fibula flaps using a specially optimized and designed reconstruction guide plate.

OUTCOMES

We achieved precise mandibular repair with such a guide in full accordance with the preoperative plan and ensured the restoration of patient facial symmetry.

LESSONS

Optimized reconstruction guide template could accurately locate the preformed reconstruction plate. This component had the ability to ensure that the location of the actual reconstruction plates were highly consistent with preoperative designed models.

Active decompression and distraction sugosteogenesis for the treatment of calcifying odontogenic cyst

The calcifying odontogenic cyst is as a benign, rare developmental odontogenic cyst with a wide range of histologic characteristics. It may present along with other odontogenic pathologies such as odontoma, ameloblastoma, adenomatoid odontogenic tumor, ameloblastic fibroma, and ameloblastic fibro-odontoma. Clinically, it can be an either intra- or extraosseous painless swelling that can produce cortical expansion. It affects mostly the anterior area of the mandible. Radiographically, it appears as a well-circumscribed unilocular radiolucency containing flecks of indistinct radiopacities. In about one third of cases, an impacted tooth is associated. In this paper, we employ a patient with an enormous calcifying odontogenic cyst to review both the pathology and active decompression and distraction sugosteogenesis, a novel technique employed to treat odontogenic entities. This dual approach usually results in an accelerated bone healing (sugosteogenesis), partial removal of the cystic epithelium, thickening of the wall, and migration of chronic inflammatory cells which triggered epithelial modulation, ultimately causing a realignment in the biologic behavior of the lesion.

MAID chemotherapy regimen as a treatment strategy for metastatic malignant ameloblastoma: A case report

RATIONALE

Ameloblastoma is generally characterized as a benign tumor originating in odontogenic epithelium. However, few cases of metastatic malignant ameloblastoma have also been reported. Due to the low incidence of malignant ameloblastoma, there is no established treatment regimen. To explore effective treatment for malignant ameloblastoma, we reported this case study.

PATIENTS CONCERNS

This report described a case of a 28-year-old malignant ameloblastoma female patient with multiple metastasis (brain and lung).

DIAGNOSES

The patient presented ameloblastoma of the left mandible in 2012. Three years later, local recurrence and brain metastasis was observed during a follow-up examination. Five years later, malignant ameloblastoma was detected by imaging and immunohistochemistry in the bilateral multiple pulmonary nodules and mediastinal lymph nodes.

INTERVENTIONS

The patient was initially treated with tumor resection. Three years later after local recurrence and brain metastasis, she was accepted the extensive mandibulectomy supplemented with brain stereotactic body radiotherapy (SBRT). When diagnosed with pulmonary metastasis, the patient received combined chemotherapy regimen of MAID (mesna, adriamycin, ifosfamide and dacarbazine) for 6 cycles.

OUTCOMES

The efficacy evaluation was partial remission (PR) after the 6 cycles of MAID. The last patient follow-up was July 24th 2018, and no evidence of progression was observed. The progression-free survival (PFS) of the patient was more than 9 months.

LESSONS

Surgical resection is the optimal treatment for locally recurrent ameloblastoma. SBRT may be an effective treatment for unresectable oligometastasis of malignant ameloblastoma. Finally, combined chemotherapy of MAID showed encouraging effects in the management of metastatic malignant ameloblastoma.

Palatal obturator designed by 3-dimensional prototyping for a patient with a large ameloblastoma: a case report

The aim of the present report was to detail the advantages of using 3-dimensional (3D) prototyping in the planning, modeling, and manufacturing of an immediate palatal obturator for a 62-year-old man who underwent a left total maxillectomy to remove a solid, multicystic ameloblastoma. The prosthesis provided favorable restoration of stomatognathic functions, including speech, swallowing, and mastication. The use of an immediate obturator prosthesis made with 3D technology is an important aid in the treatment of patients diagnosed with tumors in the head and neck region.

3D cone beam computed tomography reconstruction images in diagnosis of ameloblastomas of lower jaw: A case report and mini review

Cone beam computed tomography (CBCT) has obvious advantages over regular radiography in diagnosis of complex diseases. Objective of this study is to report a case of a mandibular jaw ameloblastoma recurring cyst, which represents a benign tumor of odontogenic epithelium, using CBCT imaging technology. CBCT examination of the patient suffering with recurrent lower jaw cyst (relapsing four years after surgery) showed a decrease in irregular bone density and appearance of a honeycomb pattern (3.5 cm×2.5 cm×1.8 cm) in the right lower jaw. This suggests that the lesion is more likely to be an ameloblastoma. Preoperative tissue biopsy and pathological examination of surgical sample confirmed the diagnosis. Surgical resection of the diseased tissue and autogenous bone grafting in the mandible was performed. Postoperative CBCT examination showed that the bone defect healed well, without recurrence of the tumor 22 months postoperatively. In conclusion, the rotated 3D CBCT images clearly displays the exact size, location, borders and internal changes of the tumor in the jaw cyst itself and the adjacent tissues. Thus, the dental CBCT allows clinicians to better evaluate lesions, leading to better treatment outcomes.

[Unicystic ameloblastoma presenting in Delleman's syndrome]

Ameloblastoma is an odontogenic tumour that represents 1 % of oral tumours but 10 % of odontogenic tumours. Ameloblastoma is characterized by low and noiseless growth, that explains a lot of advanced forms. The tumour is known as benign with local malignity due to its locally invasive behaviour and its recurrence. The treatment choice remains complicated because of recurring nature and large resection in vital anatomical areas. The therapeutic approach will be based on size, anatomical localisation, histologic variants and anatomical complications. The treatment options should be discussed with the patient because of possible important morphological and functional sequelae.

Primary Ameloblastoma of the Temporal Bone

Ameloblastoma is a locally aggressive tumor derived from odontogenic epithelium. Although benign, its clinical behavior can often exhibit malignant characteristics. It is marked by slow and persistent growth with infiltration of adjacent tissues. Almost 70% occur in the mandible in patients older than 30 years. Recurrence of ameloblastoma from inadequate treatment is frequent. Because of its slow growth, recurrences can present decades after primary surgery. A primary ameloblastoma in an area outside the mandibular, maxillary, and infratemporal fossa regions has not been described in detail to date, with only 1 possible case mentioned in the literature. The authors present a case of primary temporal bone ameloblastoma in a 17-year-old boy. The tumor originated in the left mastoid, infiltrated the lateral semicircular canal, facial nerve, and cochlea, and adhered to the sigmoid sinus and posterior cranial fossa dura. Although invasion of multiple structures in the infratemporal fossa and temporal bone leads to variable disease presentation, this case is unique because the first symptom of disease was sudden and recurring unilateral sensorineural hearing loss. Surgery required transection of the facial nerve. Histopathology confirmed primary temporal bone ameloblastoma. The difficulties in achieving wide surgical margins, diagnostics, and further management are addressed.

What Is Important for Confirming Negative Margins When Resecting Mandibular Ameloblastomas?

PURPOSE

The purpose of this study was to assess the utility of intraoperative radiographs and frozen sections in achieving negative margins and preventing recurrence of mandibular ameloblastomas.

MATERIALS AND METHODS

This was a retrospective cohort study of patients who underwent resection (≥1 cm) of mandibular ameloblastomas from 2005 through 2015. Patients were included if they had at least 1-year follow-up and complete records. Demographic variables included age, gender, and type of resection (segmental vs marginal). Predictor variables were type of margin assessment: 1) frozen section, 2) intraoperative ex vivo specimen radiograph, 3) both, or 4) none. The outcome variables were final margin status and recurrence rate. Accuracy of intraoperative radiographic margins was determined by comparison with histologic margin distance. Descriptive statistics were conducted with the Fisher exact test.

RESULTS

The study sample consisted of 35 patients (47.5 ± 20.4 yr old; 16 men) who underwent 25 segmental and 10 marginal resections. Ten had frozen sections only, 3 had ex vivo specimen radiographs only, 10 had no intraoperative measurements, and 12 had both. There were no positive frozen sections. One patient had a positive posterior bony margin at final pathology despite negative frozen section histology. There was no difference in recurrence rate at latest follow-up among cohorts. The anterior radiographic margin was 11.8 ± 5.9 mm compared with 11.5 ± 7.5 mm by histology (P = .124). The posterior radiographic margin was 12.3 ± 5.3 mm compared with 9.8 ± 6.5 mm histologically (P = .546). Margin distances that were at least 5 mm when measured with specimen radiographs had histologic margin distances of at least 5 mm in 25 of 30 resection margins (83.3%).

CONCLUSION

Resection of ameloblastoma with planned margins of at least 1 cm is sufficient to prevent recurrence of ameloblastoma. Achieving a radiographic margin of at least 5 mm provided a histologic margin of at least 5 mm 83.3% of the time.

Resection of an ameloblastoma in a pediatric patient and immediate reconstruction using a combination of tissue engineering and costochondral rib graft: A case report

BACKGROUND AND OVERVIEW

Ameloblastoma is an odontogenic tumor predominantly occurring in patients who are in their 20s and 30s. Approximately 10% to 15% of ameloblastomas occur in patients younger than 18 years. Although it is a benign tumor, an ameloblastoma can have a devastating effect on children both physically and emotionally. The aim of this case report is to demonstrate how tissue engineering and surgical techniques can minimize morbidity and recovery time after extirpation and immediate reconstruction of a mandibular ameloblastoma.

CASE DESCRIPTION

An 11-year-old girl was referred for surgical evaluation of a lesion found on a routine dental radiograph. Resection of a mandibular unicystic ameloblastoma resulted, including immediate reconstruction using a costochondral rib graft, allogeneic bone, bone marrow aspirate concentrate, and recombinant human morphogenetic protein-2. One year postoperatively, the patient had no evidence of recurrence as well as excellent mandibular bone height and width with good facial form. The patient has returned to her daily life without any disabilities or disfigurement.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Dentists are typically the first health care providers to discover oral pathology in patients. The coordination of care by the dental care providers and the oral and maxillofacial specialist was key to the successful outcome for this patient. With biotechnology and surgical techniques, the dental surgeon can extirpate an ameloblastoma and reconstruct the mandible defect to the ideal shape and size with minimal morbidity and recovery time.

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

OBJECTIVES

The 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.

DESIGN

Single case report.

SETTING

Tertiary referral center.

PARTICIPANTS

Forty-one year-old African-American male patient.

MAIN OUTCOME MEASURE

Lesion appearance on computed tomography (CT) scan and pathological correlates.

RESULTS

A 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.

CONCLUSION

Although 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.

Le Fort I osteotomy for the removal of a rare unicystic ameloblastoma lesion in the maxillary sinus

The unicystic ameloblastoma (UA) presents the clinical and radiographic characteristics of a maxillary cyst, making early diagnosis difficult. A 30-year-old man had an extensive, asymptomatic lesion in the right maxillary sinus. Radiographic examinations demonstrated a retained tooth in association with a lesion. Histopathologic examination revealed the presence of UA with intraluminal and mural infiltration and a follicular pattern. Le Fort I access was chosen for enucleation of the lesion and curettage of the site, which were followed by cryotherapy. The treatment provided adequate intraoperative visibility, enabled the preservation of the surrounding bone, and eliminated postoperative complications. Follow-up over 5 years demonstrated no recurrence.

Practitioners' challenges in diagnosing oral and maxillofacial tumors

OBJECTIVE

Oral cancer is an increasingly growing health care burden in many parts of the world. Due to the relatively low prevalence of oral cancer, screening will lead to a low yield and a high proportion of false positive results. Clinical examination without histologic diagnosis can lead to misdiagnosis in over 40% of cases, especially when premalignant lesions are involved. However, clinical examination is effective especially in detecting the early stages of oral cancer, particularly in high-risk patients, such as smokers and alcoholics. The purpose of the current paper is to describe several cases of failure to diagnose lesions in the oral cavity during clinical and radiographic examinations, and to discuss how these diagnosis failures may be mitigated.

METHOD AND MATERIALS

A series of three cases of oral tumors ranging from benign to malignant that were not recognized and referred in a timely manner, are presented.

CONCLUSION

The difficulties faced by clinicians in diagnosing oral lesions are elucidated in this case series. The current case series, presenting instances in which pathologies were not detected and/or treated in spite of obvious signs, should serve as a warning for dental professionals. The general practitioner is the "first line of defense" for symptomatic and asymptomatic patients, and therefore the implementation of well-established screening protocols is of paramount importance. In light of the low sensitivity ratio of oral examinations, use of biopsies is mandatory when a lesion is suspected.

Mandibular Reconstruction in Ameloblastoma Using Allogeneic Cord Stem Cells and Alloplastic Graft Material - Case Report

Ameloblastoma is a histologically benign odontogenic tumour and has a tendency of locally aggressive behaviour. This is second most prevalent odontogenic tumour and most common in the molar-ramus-angle region and surgical resection is only treatment option. In this article, we propose an innovative approach to deal with these cases by using alloplastic graft with cord stem cells. Over 2.5 years follow-up, we could demonstrate bone regeneration using this technique with no recurrence. To the best of our knowledge, this is the first report of successful regeneration of part of ramus and body of mandible using allogeneic cord stem cells in cases of Ameloblastoma.

A rare variant of calcifying odontogenic cyst with ameloblastoma presentation

Calcifying odontogenic cyst is a rare entity which was first described by Gorlin, and also accounts for 1% of the jaw cysts according to Shear. Due to its diverse histopathology and variable clinical features, there has been a doubt regarding its nature as a cyst or a neoplasm. In this report we present a case of calcifying odontogenic cyst with mural ameloblastomatous presentation in the left body of the mandible in a 19-year-old male patient. This is the 15th case of ameloblastomatous COC being documented in literature.

Recurrent mandibular ameloblastoma with anterior skull base invasion: Case report

Recurrent ameloblastoma with skull base invasion is a rare clinical entity with poor prognosis. We report a case of a mandibular ameloblastoma recurrence involving the anterior skull base. The diagnostic and therapeutic processes are presented with emphasis on the radiologic features of ameloblastoma. Another aim of this case report is to underline the importance of close and long-term follow-up after resection. Ameloblastoma recurrences are frequent and mainly occur after incomplete surgical resection. These recurrences may be diagnosed late because of lack of symptoms in the mandibular area.

Treatment of an extensive unicystic ameloblastoma in a 7-year-old child: the best approach?

Ameloblastoma is a benign, slow-growing neoplasm of the jaw that arises from odontogenic epithelium. We present the case of a 7-year-old girl with a unicystic ameloblastoma of the mandible, and describe our approach to treatment.

Ameloblastic carcinoma of mandible: facts and dilemmas

Ameloblastic carcinoma is a rare malignant odontogenic tumor and is considered as the malignant counterpart of ameloblastoma with features of both benign and malignant histology. It may arise de novo or from a long-standing ameloblastoma and is locally aggressive with a propensity for metastasis. With limited documentation, little is known about its pathobiogenesis, with no universal guidelines for management. For clinicians, differentiating ameloblastic carcinoma from ameloblastoma and malignant ameloblastoma in a patient presenting with a suspicious jaw tumor is a challenge due to overlapping clinical features, inconclusive cytology/biopsy reports, different management approaches and inadequate follow-up. Proper knowledge of the disease entity and a high index of suspicion are essential. Here we elaborate the dilemmas in diagnosis and management of ameloblastic carcinoma through presentation of a representative case in a 56-year-old man presenting with a tumor in the mandible.

Prominent response with helical tomotherapy in recurrent ameloblastic carcinoma of maxillary sinus: a case report

INTRODUCTION

Ameloblastoma is a benign but locally aggressive tumor of odontogenic epithelial tissue. Reports of radiotherapy treatment modalities are limited in the literature.

CASE PRESENTATION

A thirty-five year old male presented with complaints of headache radiating to his face for about six months and impaired vision. The patient's Positron Emission Tomography (PET) showed a mass in the left maxillary sinus extending to the nasal cavity and invading the adjacent tissues. An R2 (macroscopic residual tumor) surgical resection performed to debulk the tumor. Due to the recurrence and residual mass, the patient was treated with helical tomotherapy. At 2 months post-radiotherapy, patient's vision returned to normal. PET scan showed a significant reduction in lesion size 12 months post-radiation.

CONCLUSION

In cases of ameloblastic carcinoma with, post-surgical recurrence or patients not suitable for surgical treatment, helical tomotherapy can be an effective treatment option.

[Clinical research of resection of mandibular benign tumors and primary reconstruction with autogenous bone graft via an intraoral approach]

OBJECTIVE

To investigate the clinical outcomes of resection of mandibular benign tumors and primary reconstruction with autogenous bone graft via an intraoral approach.

METHODS

Fifteen patients with mandibular benign tumors were treated between January 2009 and September 2012. There were 7 males and 8 females, aged from 18 to 45 years (mean, 30 years). The pathological diagnosis identified 11 cases of ameloblastoma, 3 cases of odontogenic keratocyst, and 1 case of odontogenic myxoma. According to the Urken's CRBS (Condyle, Ramus, Body, Symphysis) classification criteria based on the location of the mandibular defect, there were 3 cases of body type (B type), 3 cases of ramus type (R type), and 9 cases of body and ramus type (BR type). The surgeries were performed via an intraoral approach, except 1 patient with the lesion at the level of sigmoid notch via an auxiliary preauricular incision. To fix the bone grafts to the dissected mandibular defects, reconstructive titanium plates were used, either indirectly according to the computer aided design/computer aided manufacturing mandibular models before surgery (9 patients) or directly according to the exposed mandibles during surgery (6 patients). The patients received benign mandibular tumor resection and primary autogenous bone graft reconstruction with free iliac bones (11 cases) or vascularized fibular flaps (4 cases). The mandibular inferior alveolar nerves were preserved in 6 cases.

RESULTS

Primary healing of incision was obtained in 14 patients, while secondary healing in 1 patient suffering from bone graft infection. All the patients were followed up 1-4 years (mean, 2.5 years). At last follow-up, no patients showed facial nerve damage; occlusion of remaining teeth was similar to preoperative conditions; the chewing function was satisfactory; mouth opening was 30-35 mm (mean, 33 mm); and swallowing and speaking functions were normal. Only slight extraoral scars caused by the auxiliary incision and the transbuccal appliances were observed, and all the patients were satisfied with the facial appearance. Lower lip numbness was relived in patients with preserved inferior alveolar nerves. There was no tumor recurrence during follow-up period.

CONCLUSION

The intraoral approach is a feasible and proper approach for resection of benign mandibular tumors and primary reconstruction with autogenous bone grafts, with the advantages of inconspicuous facial scars, minimum damage to the facial nerve, and expectable aesthetic appearance.

Reconstruction of the temporomandibular joint after surgical ablation of a multiply recurrent ameloblastoma: a case report

Reconstruction of large mandibular defects, whether involving the temporomandibular joint (TMJ) or not, has historically been achieved with autogenous grafts, such as free costochondral grafts and vascularized bone grafts. Ensuring intact, functioning microcirculation is critical for graft survival in the face of postoperative radiation therapy secondary to malignant tumour ablation. However, in the case of benign tumours, such as ameloblastomas, postoperative radiation therapy is not required, thus increasing the options for reconstruction. Alloplastic components coupled with nonvascularized bone grafts have been used successfully to restore mandibular form, function and esthetics after extensive mandibular resection. In this article, we describe a case of a multiply recurrent ameloblastoma treated by left hemimandibulectomy and immediate reconstruction with a custom-fabricated alloplastic system in combination with an anterior iliac crest bone graft. The result was a high degree of mandibular function and facial cosmesis, minimal donor-site morbidity, and nearly immediate return to function.

Malignant ameloblastoma in an 8-year-old child with metastasis to the lung: case report with a clinicopathologic analysis

Ameloblastomas are rare tumors of odontogenic origin, accounting for 1% of all oral tumors. They are benign, but locally highly aggressive tumors. We report here the unusual case of an 8-year-old patient with multicystic mandibular ameloblastoma, who was submitted to surgery for two relapses in six years and metastasized to the lung two years after initial surgery. The first lesion, diagnosed as follicular ameloblastoma, was treated conservatively with enucleation and curettage. Two years later the tumor relapsed into multicystic granular form. A marginal conservative resection was performed, keeping the basilar contour of the mandible, due to the age of the patient. Three months later, on a routine follow-up examination, a lung metastasis was detected with no signs of tumor in the mandibular bone and the patient was submitted to upper right lobectomy. Three years later a new recurrent tumor was detected in the alveolar process and another marginal resection was performed. Histologically, the tumor showed the follicular growth pattern. After a disease-free period of over five years, the patient was again submitted to surgery for mandibular reconstruction. The mandibular bony defect was filled with iliac bone blocks and four dental implants. He underwent oral rehabilitation with an implant-supported overdenture. With a follow-up period of 22 years since first surgery, the patient is currently free of disease.

Conservative treatment of an aggressive odontogenic tumor: a case report

An ameloblastoma is a polymorphic, benign, locally invasive tumor made up of odontogenic epithelium, clinically characterized by slow, progressive, painless growth. There are reports in the literature on the treatment of ameloblastomas with aggressive mural invasion through resections, in order to minimize recurrence. However, different approaches may be used at the bone level, such as curettage combined with a chemical fixative (Carnoy's solution), cryotherapy, or thermal cauterization. The findings of this case report demonstrate that the use of Carnoy's solution following the enucleation of a unicysticameloblastoma with mural invasion may be a treatment alternative with a low rate of recurrence, as well as a reduced rate of postoperative complications, a reduction in costs, and preservation of both esthetics and function.

Epidermal nevus and ameloblastoma: a rare association

Epidermal nevi are clinical manifestations of a malformation affecting the embryonic ectoderm. They appear as linear verrucous lesions and are more often located in the skin of the trunk or the extremities. Rarely, verrucous lesions affect the oral mucosa. Epidermal nevi can be a component of epidermal nevus syndrome (ENS), which is characterized by malformations involving several organs, such as the central nervous system. ENS is rarely associated with other solid tumors. We present the case of a patient affected by ENS who developed maxillary and mandibular ameloblastomas. Epidermal nevi were located in the left middle and lower third of the face and in the left cervical region, whereas the ameloblastomas arose within the left maxillary mucosa and within the left mandibular ramus. Features of the syndrome are described and the relevant literature is reviewed.

Desmoplastic ameloblastoma of the mandible

The Desmoplastic Ameloblastoma exhibits important differences in anatomical distribution, histologic appearance and radiographic findings compared with the classic type of ameloblastoma. We describe a case of desmoplastic variant of ameloblastoma localized in the mandibular anterior portion of the jaw, extending posteriorly in the left side. The tumor was expansile, slowly growing and painless. The radiographic finding showed diffuse, radiolucent lesion with cortical bone expansion. Surgical excision was performed and follow-up examination done after two years disclosed no recurrence. The purpose of this article is to assist in better understanding of this variant of odontogenic tumor.

Adenomatoid odontogenic tumor: a case report with immunohistological profile

The adenomatoid odontogenic tumor (AOT) is an uncommon tumor of odontogenic origin, composed of odontogenic epithelium and characterized by slow but progressive growth. We report a rare case of AOT in an 18-year-old, who presented with a palpable bony-hard swelling in the anterior maxillary region. The tumor was radiographically well-defined, and exhibited unilocular radiolucency. Histologically, the appearance was of solid nodules of cuboid or columnar cells of odontogenic epithelium, forming typical nests or duct-like structures. Immunohistochemistry was positive for cytokeratins (CK) CK5/6, CK17, CK19 and negative for KI-67. The results were consistent with a diagnosis of AOT.

CONCLUSION

A case of AOT is presented, emphasizing on the importance of recognizing neoplasms arising in odontogenic tissues. Recurrences seldom occur, and surgical cure is recommended.