[Is there more to hypodontia then missing teeth?] / Ernstige hypodontie: meer dan alleen ontbrekende gebitselementen?

Dental care professionals regularly see patients with hypodontia. Hypodontia can be acquired, for example through chemotherapy or radiation at a young age, but is hereditary in most patients. Due to an error (pathogenic variant) in one of the many genes that control odontogenesis, the formation of the tooth germ is disrupted at an early stage. The genes involved are not only crucial for tooth development, but they also play an important role in other physical processes. This article provides background information on hypodontia. Based on an inventory of gastrointestinal complaints in patients with hypodontia and a case description of the simultaneous occurrence of a coagulation disorder and hypodontia, the importance of a broad view of this patient group is illustrated. It is concluded that, in addition to a dental assessment, examination of these patients should include a limited physical examination and the medical history of the patient and his close relatives.

[A description of a population with severe oligodontia]. / Beschrijving van een populatie met ernstige oligodontie.

The dentition of 116 patients with a non-syndromic form of oligodontia was characterized. For this purpose use was made of the so-called Tooth Agenesis Code (TAC), with which the various patterns of missing teeth can be indicated with a unique number. Oligodontia can present itself in very diverse ways. Only 3 patterns were seen (2 times) among these 116 patients. Considered per quadrant, in the upper jaw, on the one hand, agenesis of both premolars and the lateral incisor was most common and, on the other, the absence of all teeth except the central incisor and the first molar. In the lower jaw, agenesis of the second or of both premolars was most common. Evaluating treatments and formulating standards of restoration in the treatment of patients with severe oligodontia are methodological challenges. Homogeneous, comparable sub-groups of patients of any size are difficult to construct due to the low prevalence of severe oligodontia and the diversity of patterns of agenesis when the whole mouth is taken into consideration.

[An enamel disorder in two siblings]. / Een glazuurafwijking bij twee zusjes.

Two sisters exhibit a similar enamel disorder. It is a hereditary developmental disorder, diagnosed as amelogenesis imperfecta. In this article the various types of amelogenesis imperfecta are discussed and the clinical consequences, genetic aspects, and basic guidelines for treatment are addressed.