Ameloblastoma is a benign odontogenic tumor of epithelial origin. It is locally aggressive with unlimited growth capacity and has a high potential for malignant transformation as well as metastasis. Ameloblastoma has no established preventive measures although majority of patients are between ages 30 and 60 years. Molecular and genetic factors that promote oncogenic transformation of odontogenic epithelium to ameloblastoma are strongly linked to dysregulation of multiple genes associated with mitogen-activated protein kinase, sonic hedgehog, and WNT/b-catenin signaling pathways. Treatment of ameloblastoma is focused on surgical resection with a wide margin of normal tissue because of its high propensity for locoregional invasion; but this is often associated with significant patient morbidity. The relatively high recurrence rate of ameloblastoma is influenced by the type of molecular etiological factors, the management approach, and how early the patient presents for treatment. It is expected that further elucidation of molecular factors that orchestrate pathogenesis and recurrence of ameloblastoma will lead to new diagnostic markers and targeted drug therapies for ameloblastoma. Oral Diseases (2018) 24, 307-316

Background Salivary gland tumours (SGT) are a relatively rare group of neoplasms with a wide range of histopathological appearance and clinical features. To date, most of the epidemiological studies on salivary gland tumours are limited for a variety of reason including being out of date, extrapolated from either a single centre or country studies, or investigating either major or minor glands only. Methods This study aimed to mitigate these shortcomings by analysing epidemiological data including demographic, anatomical location and histological diagnoses of SGT from multiple centres across the world. The analysed data included age, gender, location and histological diagnosis from fifteen centres covering the majority of the world health organisation (WHO) geographical regions between 2006 and 2019. Results A total of 5739 cases were analysed including 65% benign and 35% malignant tumours. A slight female predilection (54%) and peak incidence between the fourth and seventh decade for both benign and malignant tumours was observed. The majority (68%) of the SGT presented in major and 32% in the minor glands. The parotid gland was the most common location (70%) for benign and minor glands (47%) for malignant tumours. Pleomorphic adenoma (70%), and Warthin’s tumour (17%), were the most common benign tumours whereas mucoepidermoid carcinoma (26%) and adenoid cystic carcinoma (17%) were the most frequent malignant tumours. Conclusions This multicentre investigation presents the largest cohort study to date analysing salivary gland tumour data from tertiary centres scattered across the globe. These findings should serve as a baseline for future studies evaluating the epidemiological landscape of these tumours.

Childhood tooth extraction is widespread in developing nations especially in sub-Saharan African owing to high prevalence of oral diseases in the population. Purpose of this study is to analyze the reasons and pattern of tooth extraction among children from Northwest Nigeria. Case records of children <14 years seen at the dental clinic of the Federal Medical centre, Gusau, Zamfara state between January 2011 and December 2012 were retrieved from the Medical Records Department and analyzed for analyzed for gender, age, indication for extraction and tooth/teeth extracted. A total of 181 teeth were extracted in 127 patients (1.4 extractions per patients) over a 2 years study period. There were 66 (51.9%) males and 61 (48.1%) females (M:F = 1.08:1). Dental caries and its sequelae 141 (77.9%) was the leading aetiology for tooth extraction followed by trauma 24 (13.3%). Permanent teeth 121 (66.9%) were twice frequently extracted than primary teeth 60 (33.1%). Mandibular teeth 112 (61.9%) were more commonly extracted than maxillary teeth 69 (38.1%). Posterior teeth 115 (63.5%) extractions nearly double that of anterior teeth 66 (36.5%). First permanent molar extraction predominates 51 (28.1%). Majority of the extractions occurred in the 6-9 years age group 96 (53%). Mandibular posteriors constituted the principal teeth removed in the 6-9 years and 10-13 years age groups. In contrast, maxillary anteriors were the main teeth extracted in the younger age group of 0-5 years. For maxillary anteriors trauma was the highest indication for tooth extraction. In conclusion, dental caries and its sequelae was the primary reason for tooth extraction in the study across all age groups and trauma accounted signifi cantly for removal of maxillary anteriors. Thus, there is a need to critically embark on public enlightenment campaign on preventive oral health.

No abstract