Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 9 2 2022 11 19 94 99 Masoumeh Mirkeshavarz Department of Oral and Maxillofacial Pathology, School of Dentistry, Zanjan University of Medical Sciences, Zanjan, Iran. 2022 01 16 2022 11 05 Background and Objectives: The oral and maxillofacial region is exposed to many harmful agents and can be affected by a wide range of reactive, infectious, cystic, precancerous, and neoplastic  lesions. This study aimed to determine the prevalence of oral and maxillofacial pathological  lesions in pathology laboratories in Zanjan. Materials and Methods: This retrospective descriptive study was conducted in the period  2014-2020 by referring to the hospitals and laboratories with pathologists in Zanjan. Information  about patients with histopathological lesions of oral and maxillofacial region was extracted, and  studied in terms of age, gender, location and histopathological type of lesion. Finally, the collected  data were entered into SPSS software version 22 and statistically analyzed (P<0.05). Results: A total of 176 histopathological lesions were investigated. Of them, 120 cases (58%)  were female and 74 (42%) were male. The mean age of the patients was 39.4 years. The most prevalent  lesion was periapical cyst (14.8%). In terms of tissue involved, the most lesions were related  to soft tissue (67%) and in terms of anatomical location, the most lesions were gingival mucosal  lesions (35.2%). Conclusion: The prevalence of pathological lesions was higher in females than in males. Soft  tissue lesions were more than hard tissue lesions. Gingival mucosal lesions were the most prevalent  and lesions of the floor of the mouth and nasal vestibule lesions were the least prevalent ones. Given  the histopathologic nature of lesions, periapical cyst was the most prevalent lesion. https://jcr.tums.ac.ir/index.php/jcr/article/view/403 https://jcr.tums.ac.ir/index.php/jcr/article/download/403/354