Difficulty in dental management is one of the factors that characterize the patient that requires special care in dentistry. One of the clinical conditions that make dental treatment particularly complex is microstomia. Microstomia is defined as a small and insufficient oral aperture that will hinder diagnosis and dental treatment. Although there have been reports of patients with diseases and syndromes that cause microstomia, the available literature offers only a limited number of reviews on this topic. The aim of this paper is to present a review of the etiology, clinical characteristics, diagnosis and treatment of microstomia. In addition, to describe the therapeutic adaptations to be applied in dental procedures in patients with microstomia, emphasizing the importance of a preventive approach in this group of patients.