The types, incidence and demographic distribution of benign oral and maxillofacial neoplasms among patients attending Muhimbili National Hospital in Tanzania, 2008-2013

Background:
Pathological processes of oral and maxillofacial region are generally classified as benign or malignant based on specific histological criteria, including the presence or absence of necrosis, mitotic figures as well as basic understanding of the entity. The objective of this study was to determine the types, prevalence and demographic distribution of benign oral and maxillofacial tumours among patients treated at Muhimbili National Hospital in Tanzania.
Methods:
In this retrospective study, data on histological results of lesions of the oral and maxillofacial region were retrieved from the archives at the Department of Oral and Maxillofacial Surgery of Muhimbili National Hospital were analysed. The tumour type, age, sex, file number and histopathological diagnosis of the patient were recorded. The study covered a period of from January 2008 to December 2013. The top ten lesions with higher frequency of occurrence from January to were picked for analysis.
Results:
A total of 897 (males=388; females=509) histological results of patients with benign oral and maxillofacial lesions were obtained during the period under review. The age ranged from 0 to 88 years, mean age being 32.63 ± 17.1 while the age group of 20-29 and 30-39 were the most affected. A total of 136 different types of benign lesions were reported and ameloblastoma was the most common benign lesion (27.4%) followed by ossifying fibroma (18.7%), pyogenic granuloma (11.4%), pleomorphic adenoma (10.0%), and fibrous dysplasia (9.6%). Females were more affected than males, with a male to female ratio of 1:1.4 however the difference was statistically insignificant (p= 0.055).
Conclusion:
Ameloblastoma and ossifying fibroma were the most common oral and maxillo-facia neoplasms at Muhimbili National Hospital. The young age groups were the most affected by these lesions.