Epidemiological survey of mucus extravasation phenomenon at an oral pathology referral center during a 43 year period.

INTRODUCTION: Mucoceles are common benign pseudocystic lesions of the oral cavity; their main etiological factors are trauma and ductal obstruction. Two histological patterns are found: mucus retention phenomenon (MRP) and mucus extravasation phenomenon (MEP). Mucus extravasation phenomenon is the more common histological subtype and it mainly affects the lower lip. The knowledge of its main clinical features and management is important to assist health professionals in clinical practice.

OBJECTIVE: This study aimed to determine the relative frequency and distribution of oral mucoceles in an oral pathology reference center.

METHODS: Cross-sectional historical study that analyzed all cases pathologically diagnosed as mucus extravasation phenomenon by the department of anatomic pathology of an oral pathology referral center from June of 1970 to May of 2014, considering the clinical characteristics of the lesion and those relating to the patient. SPSS v. 20.0 software for Windows was used for descriptive analysis.

RESULTS: During 43 years, 719 cases of mucus extravasation phenomenon (54.7% men and 45.3% women) were registered, with the lower lip as the most commonly affected site (n=484; 67.3%). The average age of patients was 20.8 years (SD±14.4) with a peak occurrence in the second decade of life. Most professionals had oral mucocele/ranula (n=606; 84.3%) as the initial clinical impression.

CONCLUSION: Mucus extravasation phenomenon is a lesion that primarily affects young patients, affecting mainly the lower lip, and is commonly found in oral diagnostic services.