To describe the clinical, radiological and histopathological features of lateral periodontal cysts among patients diagnosed in different centers (Vall d'Hebron General Hospital, Granollers General Hospital, the Teknon Medical Center, and the Master of Oral Surgery and Implantology of the University of Barcelona Dental School; Barcelona, Spain). A retrospective observational study was made of 11 lateral periodontal cysts, all of which were diagnosed following a thorough clinical examination, radiological study and posterior histological study. The mean patient age was 37 years, and males predominated over females. The mean lesion size was 1.25 cm. A single relapse was recorded 7 years after removal of the initial lesion. All the cysts were surgically removed. Lateral periodontal cysts are very infrequent, and are characterized by the preserved vitality of the adjacent teeth. Identification of the lesion is initially based on the clinical findings, though histological study is required to confirm the diagnosis. The treatment of choice is the surgical removal, though occasional relapses have been documented.