Analysis of Prevalence and Clinical Features of Ameloblastoma and its Histopathological Subtypes in Southeast Myanmar and Lower Northern Thailand Populations: A 13-Year Retrospective Study.

INTRODUCTION: Prevalence of ameloblastomas has been established worldwide but collective data of ameloblastoma in Southeast Asian countries has not been well analyzed.

AIM: Aim of this study was to report analysis and comparison of the prevalence and demographic data of clinical features of ameloblastoma and its histopathological variants in Southeast Myanmar and lower Northern Thailand populations.

MATERIALS AND METHODS: A retrospective study on ameloblastoma was performed based on the availability of oral biopsy specimens in Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand, between January 2002 and August 2015. The collected data were subjected to descriptive statistical analyses with the SPSS version 17.0 statistical software package (SPSS Inc., Chicago, USA). Pearson's chi square (χ(2)) test and t-test were employed. The critical level of significance was set at p<0.05.

RESULTS: Total of 616 cases were reviewed, 30 cases (5%) were diagnosed as ameloblastoma with male:female ratio of 1.14:1. The mean age of the patients was 31.3±15.6 years. The predominance anatomical distribution was observed in the mandible (86.7%). Posterior body-ramus-angle region was the most common site. Almost all cases were asyptomatic and most common clinical manifestation was swelling of affected region. Multilocular radiolucency was observed in 70% of cases, whereas 30% were unilocular. Three subtypes of ameloblastomas were diagnosed: unicystic ameloblastoma (20%), conventional solid/multicystic ameloblastoma (70%), and desmoplastic ameloblastoma (10%). The most common histologic pattern was the plexiform type (57.2%) followed by follicular type (23.8%).

CONCLUSION: Prevalence of ameloblastoma in Southeast Myanmar and lower Northern Thailand populations correspond with data from other geographic areas of Thailand and other Asian countries. However, some demographic and histopathological profiles are different, with plexiform ameloblastoma being the most common subtype in this study.