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.

Paediatric jaw tumours: experiences and findings from a resource limited tertiary health care center.

INTRODUCTION: primary maxillofacial tumors are uncommon in pediatric patients. When they do occur, the tissue damage caused directly alters facial growth, development as well as psycho-social evolution. This study was carried out to determine the pattern, sociodemographic characteristics and histologic peculiarities of paediatric jaw tumors in our environment. METHODS: a retrospective hospital-based study where the case notes of children below the age of 14 years who presented with jaw tumors and tumor-like lesions from January 2014 to December 2018 were studied. RESULTS: eighty-two patients were studied; patients aged 10-14 years had the highest representation. Mean time of presentation was 8 months with jaw swelling being the commonest presentation (84.1%). Majority of the fathers were in their 4th decade of life while most of the mothers were in their third decade of life and both parents possessed primary school certificate as their highest level of educational attainment. Fathers were mostly traders, while mothers were mostly full-time housewives. The maxilla and mandible were most commonly affected with the left side showing higher preponderance. Burkitt lymphoma (19 (23.2%)) and adenomatoid odontogenic tumor (14 (17.1%)) were the commonest lesions. When the tumor involved both the maxilla and the mandible, the tumor was most likely malignant. CONCLUSION: in our center, paediatric jaw tumors are commonest in male children with the 10-14 years´ age group most commonly affected. Burkitt lymphoma and adenomatoid odontogenic tumors were the commonest tumors. Early presentation must be encouraged since these tumors if presented early can be successfully treated.

Clinical and Histopathological Analysis of Odontogenic Tumors in Institution-A 10 Years Retrospective Study.

AIM: The present study was conducted to analyze the clinical and histopathological cases of odontogenic tumors (OTs). MATERIALS AND METHODS: The present 10-year retrospective study comprised of 104 OTs. Parameters such as name, age, gender, clinical features, location, extension, etc were noted. H and E stained slides were carefully assessed by an oral pathologist and were classified according to the latest WHO classification of head and neck tumors. RESULTS: Out of 104 OTs, the most common was ameloblastoma constituting 45 cases, KCOT (28), odontoma (17), odontogenic myxoma (4), Calcifying epithelial odontogenic tumor (CEOT) (5), cementoblastoma (3) and calcifying cystic odontogenic tumor (2). The p value found to be 0.01 (significant). Common OTs was ameloblastoma (25 males and 20 males), KCOT (12 males and 16 females), odontoma (10 males and 7 females), odontogenic myxoma (3 males and 1 female), CEOT (3 males and 2 females), cementoblastoma (2 males and 1 female) and calcifying cystic odontogenic tumor (1 male and 1 female). Ameloblastoma, KCOT, and odontoma were predominantly seen in the age group 21-30 years, CEOT and cementoblastoma in age group 31-40 years. The difference was significant (P < 0.05). Common clinical features in OTs were facial disfigurement (65), swelling (78) and pain (55). The difference was non significant (P > 0.05). The average size of ameloblastoma was 6.8cm, KCOT was 4.2 cm, odontoma was 3.9 cm, odontogenic myxoma was 2.7 cm, CEOT was 5.5 cm, cementoblastoma was 3.8 cm and Calcifying cystic odontogenic tumour (COC) was 3.6 cm. The difference was non-significant (p > 0.05). CONCLUSION: Mandible exhibited more OTs as compared to the maxilla. The most common lesion was ameloblastoma, KCOT, and odontomas. We observed male predominance. CLINICAL SIGNIFICANCE: The study helps in assessing the occurrence of the odontogenic tumor. This is useful for identification and clinical management.

Odontogenic carcinosarcoma: A systematic review.

The aim of this study was to integrate the available data published on odontogenic carcinosarcoma into a comprehensive analysis of their features, treatment and recurrence. An electronic search with no publication date or language restriction was undertaken in March 2018 in the following databases: Medline Ovid, PubMed, Web of Science, Scopus and LILACS. Eligibility criteria included publications having enough clinical, imaginological and histopathological information to confirm a definite diagnosis of the neoplasm. Data were evaluated descriptively and statistically using the MedCalc software. The Kaplan-Meier method was used for survival analysis. The systematic review detected nine articles from eight countries. Six cases with no age predilection occurred in male individuals complaining of painful swelling in the posterior mandible. Radiographically, the lesions were large, with expansive radiolucency and with ill-defined borders and seven cases were associated with preexisting odontogenic lesions. Radical surgery was the treatment of choice in the majority of cases. Recurrences (n = 6), metastasis (n = 4) and death (n = 4) were frequently observed in many cases. Odontogenic carcinosarcoma is a very aggressive neoplasm with a poor prognosis. This study provides knowledge that could help surgeons, oncologists, otorhinolaryngologists and oral maxillofacial pathologists with the diagnosis and management of these lesions.

Unicystic ameloblastoma: Analysis of 370 cases in a single center in Sri Lanka.

BACKGROUND: Unicystic ameloblastoma (UA) is a variant of ameloblastoma that has a relatively benign biologic behavior and mostly occurs in a younger age group. The entire cystic lining of unicystic ameloblastoma may not always be uniformly characteristic and may partly consist of non-specific epithelium or dentigerous cyst-like lining. The variability seen reinforces the advice that multiple biopsies should be taken from large cystic lesions to represent the entire lesion. METHODS: All cases were retrieved from the archives of our unit from 1986 to 2016. Demographic data such as age, gender, and primary site were recorded. Histologically, all the cases were subcategorized according to the WHO 2017 classification. RESULTS: UA accounts for 31.1% out of all different subtypes of ameloblastoma, and male-to-female ratio is 1.08:1. Age ranged from 4 to 88 years with the mean age of 30.25 years. Peak incidence of UA was found in the range of 11-20 years, and 89% of them occurred in the mandible and 55.3% in the canine-to-first molar region. The right side was frequent in both upper and lower jaws. Of the total sample, 233 (63%) cases were luminal and 137 (37%) cases were mural, and 13 cases recurred (3.5%). CONCLUSION: The present report analyzes the largest UA sample in a single center. There is a clear need for further large case-controlled retrospective or prospective studies of the management of UA with careful and follow-up studies to draw conclusions on the correct method of treatment of these lesions.

Calcifying odontogenic cyst, dentinogenic ghost cell tumor, and ghost cell odontogenic carcinoma: A systematic review.

BACKGROUND: The aim of this study was to integrate the available data published on calcifying odontogenic cyst (COC), dentinogenic ghost cell tumor (DGCT), and ghost cell odontogenic carcinomas (GCOCs) into a comprehensive analysis of their clinicoradiological features, treatment, and recurrence. MATERIALS AND METHODS: An electronic search with no publication date restriction was undertaken in October 2017 in the following databases: PubMed, Medline Ovid, Web of Science, and Scopus. Eligibility criteria included publications containing enough clinical, radiological, and histopathological information to confirm a definite diagnosis of these lesions. Data were evaluated descriptively. RESULTS: The literature review indicated a total of 234 publications reporting 367 COCs, 55 DGCTs and 44 GCOCs. These lesions have a predilection for Asian males. COCs mainly affect the mandible and patients in the second decade of life, DGCTs mostly affect the mandible and patients in the fourth decade of life, and GCOCs mostly affect the maxilla and patients in the fifth decade of life. CONCLUSION: Conservative surgery was the most common therapy for COCs and DGCTs, while radical surgery was most common for GCOCs. This study provides important and interesting data that could help clinicians and surgeons as well as oral and maxillofacial pathologists with the diagnosis and management of these lesions.

Odontogenic myxoma: A 63-year retrospective multicenter study of 85 cases in a Brazil population and a review of 999 cases from literature.

BACKGROUND: Odontogenic myxoma (OM) is an uncommon neoplasm of the jaws. Considering the importance of defining the relative incidence and demographic profile of these lesions in South America, the aim of this study was to analyze the clinical and imagiological features of OM from three South American oral pathology services and to discuss these findings in light of the literature. METHODS: Data regarding age, gender, anatomic site, and imagiological features from 85 cases of OM were collected. Additionally, we did a review of OM studies published in three electronic databases. RESULTS: Among 63 450 oral biopsies, 1178 (1.85%) were odontogenic tumors (World Health Organization - 2017), of which 85 (7.21%) met the criteria of OM. The mean age was 30.7 years (range: 10-61 years; SD: 12.22). Forty-five (52.9%) cases occurred in females and 40 (47.1%) in males (ratio: 1:1.12). Maxilla was affected in 44 cases (53%) and mandible in 39 (47%). Of the 41 informed cases (48.2%), all of them were radiolucent lesions. The literature review indicated a majority of mean ages in third decade and a predilection for females, mandible, and multilocular radiolucent lesions. CONCLUSIONS: The features of OM samples have strong similarity to that reported in studies from other continents. It is possible to infer that geographic variation does not help to explain some differences observed in the clinical features of OM.

Melanotic neuroectodermal tumor of infancy (MNTI) of the head and neck: A French multicenter study.

OBJECTIVES: Melanotic neuroectodermal tumor of infancy (MNTI) of the head and neck is a rare entity with uncertain clinical behavior. Radical surgical resection is the current recommended treatment, however this can cause severe aesthetic and functional sequelae. The aim of this study was to clinically characterize MNTIs and to stratify risk factors that may influence locoregional recurrence. METHODS: A retrospective multicenter study, including 11 patients from eight centers with a confirmed diagnosis of MNTI, was conducted. Epidemiological, clinical, radiological, pathological, and immunohistochemical examinations were reviewed. A statistical analysis using a t-test was conducted to calculate parameters correlating with tumor recurrence. RESULTS: MNTIs mainly occurred in the maxilla, with a mean age at diagnosis of 3.18 months (range: 0-6 months). Primary surgery was performed on 10 patients, with a clear margin resection on two patients. Overall recurrence rate was 27% with a survival of 100% at time of follow-up. No statistical correlation between recurrence rate, age at diagnosis, localization, resection margins, and pathological and immunohistochemical characteristics could be established. CONCLUSION: In our study, locoregional tumor recurrence did not seem to correlate with resection margins, so a conservative surgical approach may need to be considered to avoid functional and aesthetic sequelae.

Dental anomalies in pediatric patients with familial adenomatous polyposis.

Familial adenomatous polyposis patients often present with non-malignant extra-intestinal manifestations which include dental anomalies that may be evident prior to the appearance of the colonic adenomas. The aims of this study were to describe the prevalence and type of dental anomalies and the relationships between gene mutations and dental anomalies in these patients. Twenty-two pediatric familial adenomatous polyposis patients and 46 controls, who were age and gender matched participated. Familial adenomatous polyposis patient's had a dental examination with panoramic radiograph and medical record review for age at diagnosis, the presence of the adenomatous polyposis coli gene mutation, and determination of other extra-intestinal manifestations on the body. The control group was identified from a retrospective chart review and selected if there was a current panoramic radiograph. The only significant difference between familial adenomatous polyposis patients and controls were the presence of jaw osteomas and sclerosis (p = .0001). Patients with a mutation in, or upstream of codon 1309 had a higher frequency of osteomas (77.8%) and jaw-bone sclerosis (44.4%), and 77% of these had at least one dental anomaly. This preliminary study showed an association between a genetic variant at, or upstream of codon 1309, and radiographic dental anomalies.

Ameloblastic carcinoma: a clinicopathologic analysis of cases seen in a Nigerian Teaching Hospital and review of literature.

INTRODUCTION: Ameloblastic carcinoma is a rare malignant odontogenic neoplasm that exhibits histological features of ameloblastoma in combination with cytological atypia. It may arise de novo or secondarily through malignant de-differentiation of pre-existing ameloblastoma or odontogenic cyst. Secondary ameloblastic carcinomas often results from repeated surgical intervention, which is a mainstay of odontogenic tumor management in resource limited settings. To date, relatively few cases of ameloblastic carcinomas have been reported and many cases have been misdiagnosed as ameloblastoma. This is due to its wide range of clinicopathological feature which range from indolent to aggressive. It may present as an aggressive ulcerated mass or as a simple cystic lesion; hence, it often challenging to delineate from its benign counterpart, ameloblastoma. METHODS: this study reviewed the clinicopathological data on 157 cases of odontogenic tumors diagnosed over a 10 years period from the pathology archive of the Oral Pathology Unit of Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Ile-Ife, Nigeria. RESULTS: of all these cases, we identified that 64.9% were Ameloblastomas, while 8.3% were ameloblastic carcinomas. Primary subtypes of ameloblastic carcinoma constituted 23.08%, while 69.23% of the cases were of the secondary subtype. We also found that the secondary subtype of ameloblastic carcinomas showed a higher mean duration value of 7.7 years. Most lesions were found in posterior mandible and presented with ulceration, perforation and ill-defined borders radiographically. CONCLUSION: this study is among the few that have documented higher frequency of secondary ameloblastic carcinoma in the scientific literature.

Radiotherapy and Smoking History Are Significant Independent Predictors for Osteosynthesis-Associated Late Complications in Vascular Free Fibula Reconstruction of Mandible.

BACKGROUND: The vascular fibula flap is an ideal choice for function and appearance reconstruction of mandible. Despite the high success rate, "late complications" such as Ti plate exposure and local infection related to osteosynthesis are not uncommon. PATIENTS AND METHOD: A retrospective cohort of patients who received vascular fibula reconstruction for mandible from January 2011 to December 2013 from the Department of Oral and Maxillofacial Oncology in a tertiary hospital were charted: clinical, pathological, and therapeutic factors were analyzed for late complications in univariate and multivariate analyses. RESULTS: One hundred forty-two patients were finally analyzed with median follow-up time of 47 months; 19 of them had "late complications," which occurred at a median of 8 months. Preoperative or postoperative radiotherapy (P = 0.02), type of Ti plate (P = 0.019), and the disease characteristics (P = 0.02) were significant factors on univariate. Cox regression suggested postoperative radiation (P = 0.009) and smoking history (P = 0.037) were independent significant factors for late complications. Secondary reconstruction (P = 0.069) and preoperative radiotherapy (P = 0.086) were borderline significant. CONCLUSION: Postoperative radiation and smoking history are associated with late complications. Mini Ti plate should be less used. Patients with risk factors need to be observed for at least 6 to 16 months before further management.

Clear cell odontogenic carcinoma. A review.

INTRODUCTION: Clear cell odontogenic carcinoma (CCOC) is described as an exceptional and hard to diagnose malignant tumor which was first reported by Hansen in 1985. The purpose of this review article is to show that CCOC is a not that rare entity and to discuss its various aspects in order to enhance the diagnosis. MATERIAL AND METHODS: A search in the English language literature was performed using the Scopus, ScienceDirect, PubMed and Medline databases between 1985 and 2016. Data were collected on epidemiologic, clinical, radiographic, histological, immunohistochemistrical, cytogenetic, management, follow-up and prognosis features of CCOC. RESULTS: Sixty-five studies from which a total of 95 case reports were included in the review. CCOC was generally seen in the fifth decade and the most common site was mandibular. The most frequently found symptoms were swelling, tooth mobility and pain. Radiologically, the image was radiolucent and could look like a cyst or a periodontal lesion. In situ hybridization techniques frequently expressed a gene fission of EWSR1. The treatment was mostly a radical surgical excision of the tumor with or without adjuvant radiotherapy or chemotherapy. CCOC showed high rates of recurrence and mortality related with the presence of distance metastasis. DISCUSSION: Fission of EWSR1 gene could be the main element it the diagnosis of CCOC. A multidisciplinary approach, including a radiologist, pathologist and an oral & maxillofacial surgeon may be helpful in the evaluation and management of these lesions. With 95 reports found in English literature, we cannot say that CCOC is extremely rare anymore.

Tumor odontogénico adenomatoide. Reporte de un caso y revisión de la literatura / Adenomatoid odontogenic tumor. Case report and literature review

El tumor odontogénico adenomatoide (TOA) es una neoplasia benigna de posible origen odontogénico con múltiples presentaciones en su aspecto histopatológico, por lo que ha generado controversia acerca de su etiología y diagnóstico. El objetivo del presente artículo es mostrar un caso clínico con su diagnóstico clínico e histopatológico y plan de tratamiento; adicionalmente se hace una revisión de literatura (AU)

The adenomatoid odontogenic tumor (TOA) is a benign neoplasm of possible odontogenic origin with multiple presentations in its histopathological aspect, reason why it has generated controversy about its aetiology and diagnosis. The aim of this article is to show a clinical case with its clinical and histopathological diagnosis and treatment plan; additionally a literature review is done (AU)

Clinicopathological and cell proliferation evaluation of ameloblastomas and keratocystic odontogenic tumors: a 10 year retrospective study.

Odontogenic tumors (OTs) are important lesions of the gnathic bones due to their clinicopathological heterogeneity and variable biological behavior; therefore, epidemiological studies are needed to outline the incidence and behavior of these tumors. To evaluate the incidence and epidemiological profile of ameloblastoma (AMB) and keratocystic odontogenic tumor (KCOT) from an oral pathology service, and correlate morphological findings of these tumors with the immunoexpression of a cellular proliferation marker (Ki-67), a retrospective study (2002-2012) was conducted to characterize demographic, clinical, radiological, and morphological data of AMBs and KCOTs. Then, a representative sample composed of 49 cases of each tumor was selected to perform immunohistochemical (IHC) analysis of Ki-67 through the streptavidin biotin peroxidase technique. For statistical analysis, we used Fisher's exact test (p < 0.05). A total of 279 OTs were found in the service, in which 91 (32.6%) were AMB and 98 (35 %) were KCOT. Most cases occurred in white women, and the average age of patients with AMB and KCOT was 32 and 33 years, respectively. The maxilla-mandible ratio was 1:6 and 1:3.6 for AMB and KCOT, respectively. Regarding IHC analysis, AMB and KCOT had similar levels of cellular proliferation. However, KCOTs with intense inflammation showed higher Ki-67 expression (p < 0.001). Recurrent cases had similar Ki-67 immunoexpression. The demographic profile of the studied tumors corroborates with data reported in the literature, and the levels of cellular proliferation were similar in both tumors, although the inflammation seems to induce a differential proliferative behavior in KCOT.

A multi-centre evaluation of oral cancer in Southern and Western Nigeria: an African oral pathology research consortium initiative.

INTRODUCTION: Oral cancer is a leading cause of cancer deaths among African populations. Lack of standard cancer registries and under-reporting has inaccurately depicted its magnitude in Nigeria. Development of multi-centre collaborative oral pathology networks such as the African Oral Pathology Research Consortium (AOPRC) facilitates skill and expertise exchange and fosters a robust and systematic investigation of oral diseases across Africa. METHODS: In this descriptive cross-sectional study, we have leveraged the auspices of the AOPRC to examine the burden of oral cancer in Nigeria, using a multi-centre approach. Data from 4 major tertiary health institutions in Western and Southern Nigeria was generated using a standardized data extraction format and analysed using the SPSS data analysis software (version 20.0; SPSS Inc. Chicago, IL). RESULTS: Of the 162 cases examined across the 4 centres, we observed that oral squamous cell carcinomas (OSCC) occurred mostly in the 6th and 7th decades of life and maxillary were more frequent than mandibular OSCC lesions. Regional variations were observed both for location, age group and gender distribution. Significant regional differences was found between poorly, moderately and well differentiated OSCC (p value = 0.0071). CONCLUSION: A multi-centre collaborative oral pathology research approach is an effective way to achieve better insight into the patterns and distribution of various oral diseases in men of African descent. The wider outlook for AOPRC is to employ similar approaches to drive intensive oral pathology research targeted at addressing the current morbidity and mortality of various oral diseases across Africa.

A retrospective review of 61 cases of adenomatoid odontogenic tumour seen in five tertiary health facilities in Nigeria.

INTRODUCTION: Adenomatoid odontogenic tumor (AOT) is a benign lesion originating from the dental lamina or its remnants. It is a relatively uncommon neoplasm representing about 3% of all odontogenic tumors. The aim of this study was to examine the clinical and radiological characteristics of AOTs in five major tertiary centres in Nigeria. METHODS: Archival hospital-based data stores of five tertiary health facilities in Nigeria were accessed. Case files and biopsy records were retrieved to obtain relevant information. Data was collected according to a proforma for standardization and entered into and analysed using SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL). RESULTS: 61 (4.5%) cases of AOT were documented. The age range was 8-46 years with a mean age of 20.4±9.9 years. Male: Female ratio was 1:1.3. The anterior maxilla had 34 (55.8%) cases and the anterior mandible had 20 (32.8%) cases. 40 (65.6%) follicular cases, 20 (32.8%) extra-follicular cases and 1(1.6%) extra-osseous case were found. 31 cases (61.1%) were associated with impacted teeth and the upper canine was involved in 19 (57.6%) cases. CONCLUSION: This study showed AOT to be more common in the maxilla, more in females, most often associated with impacted canines, however, the suggestion of AOT being a "Two third tumour" was not observed in this study.

Retrospective study of 289 odontogenic tumors in a Brazilian population

BACKGROUND: Odontogenic tumors (OTs) are considered important among oral lesions because of their clinicopathological heterogeneity, and variable biological behavior. This paper aims to determine the frequency and distribution of OTs, over a period of 10 years, at a public university in Northeastern Brazil and compare this data with previous reports. MATERIAL AND METHODS: We reviewed all cases of OTs from oral pathology laboratory of University of Pernambuco (UPE), from 2004 to 2014. Diagnoses were re-evaluated and the tumors were classified according to the latest (2005) World Health Organization Classification of Tumors. In addition, we searched in the English-language literature retrospective studies on OTs that used the same classification. RESULTS: Within the total of 6028 oral biopsies, 289 (4.79%) were OTs. Of these, 287 (99.3%) were benign and 2 (0.7%) were malignant. The overall incidence was 31.1/million. Mandible-maxilla ratio was 2.5:1 and mean age 35 years. Keratocystic odontogenic tumor (KCOT) (34.6%) was the most frequent lesion, followed by ameloblastoma (AMB) (32.9%) and odontoma (ODO) (11.4%). CONCLUSIONS: OTs are uncommon neoplasms with geographic variation. Our clinicopathological features are according to literature. In the present study, KCOT was the most frequent one, showing that the new classification of OTs altered the distribution of these lesions and possibly made KCOT the most common OT observed in diagnostic services worldwide

Epithelial odontogenic tumors: analysis of 156 cases in a Brazilian population / Tumores odontogénicos epiteliales: análisis de 156 casos en una población brasileña

The objective of this study was to determine the distribution of epithelial odontogenic tumors diagnosed histologically in a period of 41 years in a Brazilian population according to age, gender, site affected and compare these data with previously reported studies from other countries. Data of epithelial odontogenic tumors diagnosed were collected from the files of the Oral Pathology Laboratory of Federal University of Rio Grande do Norte, Natal, RN, Brazil, and entered in a standardized form for later comparisons. Clini-cal features obtained from the patient records and microscope slides were reviewed according to the 1992 World Health Organization classification. A total 156 epithelial odontogenic tumor were reported. Of these, all of them were benign. Ameloblastoma was the most frequent type (85.9 %), followed by adenomatoid odontogenic tumor (10.9 %) and calcifying epithelial odontogenic tumor (3.2 %). The mean age of the patients was 38 years, with a wide range (11­80 years). The posterior region of mandible was the anatomic site most frequently affected by this disease, and no significant differences were found between sexes in the diagnosis of odontogenic tumors. A marked geographic variation in the relative incidences of various epithelial odontogenic tumors was found. It was particularly notable in ameloblastomas and adenomatoid odontogenic tumors, with the incidences observed in the present study being similar, sometimes different to earlier studies in others parts of the world.

El objetivo fue determinar la distribución de los tumores odontogénicos epiteliales diagnosticados histológicamente en un período de 41 años en una población brasileña según edad, sexo y la zona afectada y comparar estos datos con estudios anteriores de otros países. Los datos de los tumores odontogénicos epiteliales diagnosticados fueron obtenidos de los archivos del Laboratorio de Patología Oral de la Universidad Federal de Rio Grande do Norte, Natal, RN, Brasil, e introducidos en un formulario estandarizado para comparaciones futuras. Las características clínicas obtenidas a partir de los registros de los pacientes y los portaobjetos de microscopio fueron revisados de acuerdo a la clasificación de la Organización Mundial de la Salud 1992. Se informó de un total de 156 tumores epiteliales odontogénicas. De estos, todos eran benignos. Ameloblastoma fue el tipo más frecuente (85,9 %), seguido por el tumor odontogénico adenomatoide (10,9 %) y el tumor odontogénico epitelial calcificante (3,2 %). La edad media de los pacientes fue de 38 años, con un rango amplio (11­80 años). La región posterior de la mandíbula era el sitio anatómico más afectado por esta enfermedad, y no se encontraron diferencias significativas entre sexos en el diagnóstico de los tumores odontogénicos. Se encontró una marcada variación geográfica en las incidencias relativas de diversos tumores odontogénicos epiteliales. Fue particularmente notable en ameloblastomas y tumores odontogénicos adenomatoide, con las incidencias observadas en este estudio siendo a veces similares, y a veces diferentes de los estudios anteriores en otras partes del mundo.

A 40-year Retrospective Clinicopathological Study of Ameloblastoma in Iran.

Ameloblastoma is the most common epithelial odontogenic tumor. It may show locally invasive behavior resulting in recurrence and malignancy. Therefore, appropriate diagnosis of this tumor is necessary. The aim of this study was to evaluate clinicopathological characteristics of ameloblastomas in an Iranian population. We present a 40-year retrospective study of patients diagnosed from 1971 to 2010 in the Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mashhad, Iran. Information gathered from patient records included age, gender, tumor location and histologic type. The frequency of odontogenic tumors among all lesions was 2.08% and ameloblastoma with 88 samples demonstrated the greatest prevalence (41.5%). Regarding gender, 60% of samples occurred in males. The mean age of studied patients was 33.02± 15.74 years with a peak of occurrence in the third decade of life. The most frequent location of tumor was the mandibles (93.2%). Eighty five (96.6%) tumors were recorded as benign and 3 (3.4%) as malignant. Of benign tumors, 62 (72.9%), 20 (23.5%) and 3 (3.6%) cases were of conventional, unicyctic and peripheral types, respectively. In contrast to most previous studies, the most common histologic subtype in the present study was plexiform. Knowledge of the incidence of ameloblastoma and its clinicopathologic features including most common location, gender and age distribution in different ethnogeographic backgrounds is necessary for accurate diagnosis and proper treatment.

Odontogenic myxoma: a clinicopathological study in a South African population.

BACKGROUND: Odontogenic myxoma is a benign, locally aggressive neoplasm of the jaws. Prevalence rates range between 0.5% and 17.7% of odontogenic tumours. There are few reports in the literature on this lesion in African populations, and therefore, this study aimed to report on odontogenic myxoma in a South African population over a 40-year period. METHODS: The clinical records and orthopantomograms of 29 histopathologically diagnosed odontogenic myxoma were retrospectively analysed. Details of age, gender, ethnic origin and clinical, histological as well as radiological features were recorded. RESULTS: The ages of patients ranged from 7 to 44 years with a mean of 21.3 years. The male-to-female ratio was 1:2.6 with the majority of patients being of mixed race and Africans. Clinically, 31% complained of pain while 58.6% had a history of swelling. The majority of odongenic myxomas (62.1%) were located in the mandible with the posterior region being most commonly affected. Multilocular lesions (69.2%) were more common and were significantly larger than unilocular lesions (P < 0.05). The outline of these tumours was mostly well-defined (84.6%) with different degrees of cortication. Only one tumour caused tooth resorption, while 20 cases (76.9%) caused tooth displacement. Six tumours expanded into the maxillary sinus, and 14 tumours caused expansion of the mandible. CONCLUSIONS: Odontogenic myxomas have variable clinical, radiological and histological features. Most of these features in this population were similar to other populations. It is mandatory to use conventional radiographs along with histopathological examination to aid in arriving at an accurate diagnosis.