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.

The validity of ultrasonography in the diagnosis of zygomaticomaxillary complex fractures.

The aims of this study were to determine the sensitivity, specificity, positive and negative predictive values of ultrasonography in detecting zygomaticomaxillary complex fractures, and to highlight factors that may affect the validity of ultrasonography in the diagnosis of zygomaticomaxillary complex fracture. Twenty-one patients with suspected fractures of the zygomaticomaxillary complex presenting at the authors' hospital were included in this prospective study. All the patients had plain radiographic and computed tomography (CT) investigations. All underwent ultrasonographic examination of the affected region using an ultrasound machine with a 7.5 MHz probe. The different radiologists were not aware of the results of the other two investigations. Statistical significance was inferred at P<0.05. The validity of ultrasonography varied with fracture sites with a sensitivity of 100% for zygomatic arch fractures, 90% for infraorbital margin fractures and 25% for frontozygomatic suture separation. Specificity was 100% for the three types of fracture. There was no statistically significant difference in the ability of CT scan and ultrasonography to diagnose fractures from various zygomaticomaxillary complex fracture sites (P=0.47). Ultrasonography has proved to be a valid tool for the diagnosis of zygomatic arch and displaced infraorbital margin fractures.

Clinico-epidemiological analysis of orofacial rhabdomyosarcoma in a Nigerian population.

Rhabdomyosarcoma (RMS) is a malignant soft tissue neoplasm, with varying degrees of striated muscle cell differentiation and a relative predilection for the head and neck region. The objectives of this study were to determine the clinical and histological patterns of RMS, to assess the sociodemographic profile of reported RMS cases, and to highlight the management challenges and outcomes of these cases in a country lacking resources such as Nigeria. Patients diagnosed with RMS, based on clinical and histological evaluation, and recorded in the cancer registry of two maxillofacial centres in Nigeria were reviewed. 21 patients met the inclusion criteria for this study. Their ages ranged from 24 days to 42 years. In all of them multiple anatomical sites were involved. The primary site of the lesion could not be determined. Embryonal and alveolar subtypes were mainly found in the maxilla. There was no statistically significant association between the site of the lesion and the histological type (p=0.39). The patients' age was statistically significantly associated with the histological type (p=0.008). Most patients reported at an advanced stage, contributing to the poor prognosis and management outcome of cases evaluated.