167 Journal of Oral and Maxillofacial Pathology Vol. 16 Issue 2 May - Aug 2012 167 Cysts of the oro-facial region: A Nigerian experience Lawal AO, Adisa AO, Sigbeku OF 1 Department of Oral Pathology, College of Medicine, University of Ibadan, 1 Oral Pathology, University College Hospital Ibadan, Ibadan, Nigeria ORIGINAL ARTICLE Address for correspondence: Dr. AO Lawal, Department of Oral Pathology, College of Medicine, University of Ibadan, Ibadan, Nigeria. E-mail: toytoy219@yahoo.com ABSTRACT Aim: Though many studies have examined cysts of the jaws, most of them focused on a group of cysts and only few have examined cysts based on a particular classification. The aim of this study is to review cysts of the oro-facial region seen at a tertiary health centre in Ibadan and to categorize these cases based on Lucas, Killey and Kay and WHO classifications. Materials and Methods: All histologically diagnosed oro-facial cysts were retrieved from the oral pathology archives. Information concerning cyst type, topography, age at time of diagnosis and gender of patients was gathered. Data obtained was analyzed with the SPSS 18.0.1 version software. Results: A total of 92 histologically diagnosed oro-facial cysts comprising 60 (65.2%) males and 32 (34.8%) females were seen. The age range was 4 to 73 years with a mean age of 27.99 ± 15.26 years. The peak incidence was in the third decade. The mandible/ maxilla ratio was 1.5:1. Apical periodontal was the most common type of cyst accounting for 50% (n = 46) of total cysts observed. Using the WHO classification, cysts of the soft tissues of head, face and neck were overwhelmingly more common in males than females with a ratio of 14:3, while non-epithelial cysts occurred at a 3:1 male/female ratio. Conclusion: This study showed similar findings in regard to type, site and age incidence of oro-facial cysts compared to previous studies and also showed that the WHO classification protocol was the most comprehensive classification method for oro-facial cysts. Key words: Classification, Ibadan, oro-facial cysts Access this article online Quick Response Code: Website: www.jomfp.in DOI: 10.4103/0973-029X.98448 INTRODUCTION A cyst is defined as a pathological cavity which may contain fluid or semi-fluid contents and which is not created by the accumulation of pus. [1] It was initially defined by Killey and Kay as a pathologic epithelium-lined cavity usually containing fluid or semisolid material. [2] Cysts of the oral and maxillofacial region that are lined by epithelium are known as true cysts, for example, dentigerous cyst; while those not lined by epithelium are generally referred to as pseudo-cysts, for example, the mucous extravasation cyst of the salivary glands, the aneurysmal bone cyst and the solitary bone cyst. [1] Cysts, especially epithelial cysts, are more commonly seen in jaw bones than other parts of the body because of numerous epithelial rests that develop in intimate relationship with developing bone. [3] Various classifications of cysts of the oral and maxillofacial region have been published [Table 1]. [2] Though many studies have examined cysts of the jaws, most of them focused on a group of cysts [4-6] and only few have examined cysts based on a particular classification. The aim of this study was to review cysts of the Oro-facial region seen at a tertiary health centre in Ibadan and attempt to group the cases using the Lucas (1966), the Killey and Kay (1968) and WHO (1992) classification protocols. MATERIALS AND METHODS This was a retrospective study of oro-facial cysts seen at the oral pathology department of the University College Hospital Ibadan. All histologically diagnosed oro-facial cysts seen in the department over a 10-year period (1999- 2009) were retrieved from the oral pathology archives. Cysts diagnosed as odontogenic keratocysts (OKC) were excluded from the study. Information concerning cyst type, topography, age at time of diagnosis and gender of patients were retrieved.