Hereditary dentine dysplasias (HDD) such as dentinogenesis imperfecta (DI) and dentine dysplasia (DD) are a group of genetic conditions characterised by an abnormal dentine structure due to disturbances in the formation, composition, or organisation of the dentine matrix. Either the primary or both primary and secondary dentition are affected to varying degrees. These disorders result from mutations in the genes encoding the major protein constituents of dentine, notably collagens and phosphoproteins. The clinical and radiological features of the hereditary dentine dysplasias (HDD) are relevant to clinical dentistry, in particular osteogenesis imperfecta (OI) which is a well-known heterogeneous genetic disorder. OI is currently the focus of considerable academic attention and involvement of the teeth is a frequent and variable manifestation. In this analysis, the literature related to the classification, clinical features, and molecular pathogenesis of heritable structural tooth diseases affecting dentine formation is reviewed. The definition, history of the terminology and the development of the current classification is outlined and discussed in detail with the aim to address semantic confusion that has arisen in the literature on HDD and to provide clarity on the use of appropriate terminology in the context of OI.