A geographical analysis of ethnic distribution of jaw ameloblastoma in Nigerians.

INTRODUCTION: Ameloblastoma is the most common odontogenic tumour in Nigeria. A definite geographic variation has been observed in the frequency of odontogenic tumors from different parts of the world. However, there is no study on the regional variations in Nigeria. Hence, this study was designed to document the ethnic and geographical distribution of jaw ameloblastoma in Nigeria. METHODS: Archival data on ameloblastoma from 10 health facilities were obtained. Global Moran's I detected geographic clustering in its distribution while Local Getis Ord indicated the location of ameloblastoma clusters. Chi-square tested associations between variables at 0.05 level of significance. RESULTS: A total of 1,246 ameloblastoma cases were recorded in Nigeria. Besides substantial state variations, a South-North gradient was noticed in its distribution. Significant positive spatial autocorrelation was observed in the three major groups while ameloblastoma hotspots were found in the SouthWestern and Northwestern Nigeria. The Igbos had a higher prevalence of ameloblastoma outside their home region than within. CONCLUSION: The study hypothesized that the geographical distribution of ameloblastoma in Nigeria is the result of all or one of the following: the country's tropical climate, migration patterns and health seeking behavior. Hopefully, these claims should lead to further enquiry on the underlying causes.

Biological profile of ameloblastoma and its location in the jaw in 1246 Nigerians.

OBJECTIVES: Ameloblastoma is a benign, slow-growing, locally invasive epithelial tumor of odontogenic origin, with unlimited growth capacity and a strong tendency to recur. This multicentric study analyzed ameloblastoma diagnosed in Nigeria among different ethnic groups. STUDY DESIGN: This retrospective study included ameloblastoma cases diagnosed from 1964 to 2017 at 10 hospitals or medical centers in Nigeria. Age, sex, tribe, and location of the ameloblastoma in the jaw were analyzed. Associations between variables were tested by using χ2 and Fisher's exact test. RESULTS: A total of 1246 ameloblastoma cases were recorded (mean patient age 32.51 ± 14.54 years; range 4-86 years; male-to-female ratio 1.2:1). Approximately 60% of ameloblastoma cases occurred in young adults (age range 18-40 years). Ninety-eight lesions were located in the maxilla and 1103 in the mandible; the posterior mandible was the most common site (31.3% on the right and 26.5% on the left, respectively), followed by the anterior (26.0%) mandible. No significant differences were noted in the distribution of ameloblastoma within the tribes with respect to age (P = .92) and sex (P = .71). CONCLUSIONS: The mandible is a common site of ameloblastoma in patients in Nigeria, and in most cases, it occurs in young adults. Early presentation, diagnosis, and treatment are important to reduce postoperative disfigurement and morbidity.

A prospective epidemiological study on odontogenic tumours in a black African population, with emphasis on the relative frequency of ameloblastoma.

The persistent view in the literature is that the relative frequency of ameloblastomas is higher in the black population than in Caucasians. The aim of this study was to determine the relative frequency of all odontogenic tumours (OT) in a 100% black population and to compare our findings with those of previous studies. A prospective study was undertaken of all patients presenting with OT to all 16 Nigerian departments of oral and maxillofacial surgery over a 4-year period. The following data were obtained: patient demographics, delay to presentation, extent of the lesion, and histological diagnosis. Six hundred and twenty-two cases were studied. A slight male preponderance was observed (male to female ratio 1.17:1). Patients ranged in age from 5 to 89 years, with a peak incidence in the third decade. The relative frequency of OT was 0.99 per million and that of ameloblastoma was 0.76 per million. Ameloblastoma was the most prevalent OT (76.5%), followed by adenomatoid odontogenic tumours (5.6%), odontogenic myxoma (4.5%), and keratocystic odontogenic tumours (KCOT) (3.1%). The relative frequency of ameloblastoma among Nigerians was not different from frequencies reported previously among Caucasian and Tanzanian black populations. KCOTs were, however, rarely diagnosed in Nigerians as compared to the white population in the Western world.

[Ameloblastoma of the jaws. A retrospective analysis from 1994 to 2007]. / Améloblastomes des mâchoires. Analyse rétrospective de 1994 à 2007.

INTRODUCTION: Ameloblastomas and keratocysts are the most frequent epithelial odontogenic tumors of the jaws. They have a high recurrence rate. This retrospective study reviews the features of ameloblastomas operated on in our unit from 1994 to 2007. PATIENTS AND METHODS: The studied parameters were sex, ethnic origin, age at diagnosis, clinical signs, radiographic presentation, site distribution, histological type, treatment, and follow-up records. RESULTS: One hundred and sixteen patients were included (with 239 surgical samples). The mean age was 36 years, with a majority of Europeans, 60% of multilocular radiolucent lesions with root resorption, mandibular location (93%). Twenty-one percent of the patients presented with an impacted tooth, the third molar in 79% of cases. Fifty percent of the lesions were from 5 to 13cm in length, 10% longer than 13cm. The most common histological type was follicular ameloblastoma. Patients were treated by enucleation in 82% of cases and radical mandibular resection with reconstruction in 11% of cases. The follow-up was documented for 96% of the patients with a 44% recurrence rate. Seventy-four percent of patients with a double recurrence presented with a "follicular" ameloblastoma. DISCUSSION: We prefer a well-performed enucleation which preserves surrounding bone. The high rate of follicular type recurrence should more systematically lead to a combined treatment: periostectomy and tooth extraction. Our data was compared with previously published large series.

A clinical, radiographic, and histologic review of 73 cases of ameloblastoma in an Indian population.

OBJECTIVE: Ameloblastomas in Indians have rarely been studied. The present study was undertaken to retrospectively compare the clinical, radiologic, and histopathologic features of 73 cases of ameloblastoma in Indians. METHOD AND MATERIALS: Biopsy records of 73 histologically diagnosed cases of ameloblastoma over an 18-year period were retrieved and analyzed for age, sex, site distribution, clinical presentation, radiologic features, and histopathology. These cases were also evaluated for recurrence. RESULTS: Ameloblastoma accounted for 60.3% of all odontogenic tumors in this study, with a mean age of presentation of 30.2 years. A slight male predilection and predominant occurrence in the mandibular molar-ramus area were noted. Radiologically, ameloblastoma presented as either unilocular or multilocular radiolucency, with a significant age difference noted between unilocular and multilocular lesions. Interestingly, findings such as cortical plate expansion, perforation, and involvement of the temporomandibular joint were more frequent in females. The most common histologic type in contrast to other studies was unicystic ameloblastoma followed by follicular and acanthomatous ameloblastoma. Specific correlations between histologic type and age, sex, site, and radiologic features were also observed. Recurrence was seen in 13.3% of patients, predominantly in males, in the molar-ramus area, and the common histologic type was follicular ameloblastoma followed by unicystic ameloblastoma. CONCLUSION: The finding of unicystic ameloblastoma being the second most common recurrent variant of ameloblastoma, especially when associated with cyst wall invasion or intramural proliferation, may warrant a more aggressive treatment than traditional enucleation/curettage for this entity to prevent recurrence.

Estudo retrospectivo dos casos diagnosticados como ameloblastoma no Serviço de Anatomia Patológica do Hospital Universitário Antônio Pedro entre 1997 e 2007 / A retrospective study of ameloblastoma in the Anatomic Pathology Service of Antônio Pedro University Hospital between 1997 and 2007

INTRODUÇÃO: O ameloblastoma é um tumor odontogênico de origem epitelial que, pela freqüência, subtipos clínicos, grande capacidade infiltrativa e alta tendência à recorrência tem merecido bastante atenção. OBJETIVO:Realizar estudo retrospectivo dos casos diagnosticados histopatologicamente de ameloblastoma no Serviço de Anatomia Patológica do Hospital Universitário Antônio Pedro da Universidade Federal Fluminense (HUAP/UFF) no período de 1997 a 2007. Material e métodos: Foram selecionados casos de ameloblastoma correspondentes ao período da pesquisa, e dados como idade, sexo, raça, localização da lesão, aspecto radiográfico, tipo de biópsia, diagnósticos clínico e histopatológico foram compilados das fichas de requisição e/ou prontuários. RESULTADOS:Depois do levantamento e da revisão das lâminas para confirmação do diagnóstico de ameloblastoma, a amostra totalizada foi de 23 casos. Os pacientes mais acometidos eram do sexo masculino, leucodermas e estavam entre a primeira e a terceira década de vida. Todos os casos ocorreram na mandíbula, sendo a região posterior a mais afetada. Predominaram o aspecto radiográfico multilocular e, histopatologicamente, o padrão multicístico, sendo os subtipos folicular e híbrido os mais freqüentes. Não foram observados casos de ameloblastoma desmoplásico e de células basais. CONCLUSÕES: A freqüência do ameloblastoma varia de acordo com a região geográfica avaliada, e a realização de estudos retrospectivos pode contribuir para a identificação de grupos e dos possíveis fatores associados ao seu desenvolvimento.

BACKGROUND: Ameloblastoma is an odontogenic tumor of epithelial origin that has received considerable attention due to its frequency, clinical subtypes and high tendency to infiltrate and recur. OBJECTIVE: To perform a retrospective study of cases histopathologically diagnosed of ameloblastoma at the Pathological Anatomy Department of APUH/UFF-RJ from 1997 to 2007. Material and methods: We selected cases of ameloblastoma corresponding to the period of this research. Data such as age, gender, race, location of lesion, radiographic features, type of biopsy, clinical diagnosis, and histopathological diagnosis were compiled from patients' records. RESULTS:After the investigation and review of slides for confirmation of the diagnosis of ameloblastoma, the sample comprised 23 cases. Most patients with ameloblastoma were male, Caucasian and age range 10-30. All lesions were in the mandible, mainly in the posterior region. The multilocular radiographic types were predominant, and histopathologically, multicystic type, whereas the follicular and hybrid ones were more frequent. There were no cases of desmoplastic and basal cells ameloblastoma. CONCLUSIONS:The frequency of ameloblastoma varies according to geographic analyzed region, and retrospective studies can contribute to identify groups and possible factors associated with its development.

Unicystic ameloblastoma in the sudan.

7 Sudanese patients, 4 females and 3 males, aged 15 to 56 years, were seen with a preoperative diagnosis of odontogenic cyst. The lesions were removed via conservative surgical enucleation. The histological interpretation was unicystic ameloblastoma. Despite the conservative treatment, all 7 patients are free of recurrence up to 6 years after surgery.