In cases of periapical lesions of unknown origin we have to keep in mind the possibility of dentin dysplasia. From the differential diagnostic point of view of differential diagnosis it is important to recognize this disease as it significantly influences the treatment modality. It is an anomaly of unknown etiology that could affect both deciduous and permanent dentition. Dentin dysplasia presentation varies clinically and radiologically. A rare manifestation which affects 1: 100000 patients is spontaneously occurring either as periapical abscess or odontogenic cyst. The affected teeth could become mobile and eventually lost. Dentin dysplasia is a genetic disease which shows autosomal dominant inheritance and characterized by abnormal formation of dentin structure which occurs during tooth development. For this article we have reviewed available literature and PubMed database. Dentin dysplasia increases the risk of early tooth loss and associated with it esthetic and functional disturbances. As a result it can influence the psychological and social status of the patients and affect their quality of life.