Focus on odontohypophosphatasia

Introduction: Hypophosphatasia (HPP) is a disease that was first described by the canadian pediatrician John Campbell Rathbun in 1948. The objective of this work is to define hypophosphatasia and its various clinical forms, to define the repercussions of the HPP on the oral cavity, to establish the means of diagnosis and to describe the management of this pathology. Materials and methods: To achieve these objectives, we adopted two documentary research strategies: computer research and manual research. Then we chose some recent and relevant articles that we read correctly. Results: Hypophosphatasia is a rare metabolic disease characterized by a deficient enzymatic activity of the tissue-nonspecific alkaline phosphatase (TNAP) that generates a defective mineralization of bone and/or teeth. Six forms of HPP are distinguished, odontohypophosphatasia is the most benign form of the disease and it’s characterized by premature exfoliation of primary and/or permanent teeth without skeletal manifestations. The early loss of teeth is explained by an anomaly in the formation of the cementum, which ensures the attachment of the tooth to the alveolar bone via the alveolar-dental ligament. In addition to the early loss of teeth, these patients may have defective mineralization of dentin and / or enamel hypoplasia and thus increased susceptibility to caries. A reduced enzymatic activity of Alkaline phosphtase (ALP) measured on a blood sample is the key marker of the disease, and the genetic test confirms this diagnosis. No established therapy has been available until the recent success of enzyme replacement therapy (ERT) using Asfotase Alfa. This therapy was able to prevent the early loss of teeth in infants. Conclusion: The dentist plays a very important role in screening for HPP, when the patient present an early loss of the primary teeth and / or permanent without traumatic history, the dentist should suspect hypophosphatasia.