Hyperdontia (or hyperodontia) refers to an excess number of teeth, where there are then over 32 teeth in the permanent dentition and over 20 teeth in the primary dentition.
What is hyperdontia?
Hyperdontia is an excess of teeth that can occur as multiple or double structures, as twin teeth, as fusions or as adhesions. Fusions or adhesions can then look like one large tooth. Double formations are caused by fusions of adjacent teeth in the cementum or dentin, respectively. If a tooth fuses with a supernumerary tooth, this is called gemination. Most often, these formations occur in the anterior region, which also leads to esthetic problems. An accumulation of hyperdontia can be found especially in cleft palate, cleft jaw or cleft lip. In the deciduous dentition, hyperdontia occurs rather rarely and is then mainly localized in the upper jaw. In most cases, it involves additional incisors. Hyperdontia is more common in the permanent dentition, where it occurs more often in the male sex. Supernatural teeth can have a natural tooth shape. In this case they are called eumorphic. On the other hand, if their shape is atypical, they are called dysmorphic. These include paramolars, distomolars, and mesiodentes, respectively. Mesiodentes very often have the shape of a cone and are found between the roots of the upper central incisors. This can interfere with the natural eruption of the teeth. Paramolars and distomolars are molars that can occur behind the wisdom teeth and between the molars, respectively.
Causes
The cause of hyperdontia is not well understood, but tooth germ splitting, overproduction of the dental arch, atavism, or local developmental abnormalities could be responsible. Sometimes hyperdontia also occurs in families or together with other diseases such as Klippel-Feil syndrome as well as dysostosis (disorder of bone formation). The following forms can be distinguished in hyperdontia:
- Mesiodentes: the most common form of tooth hyperdentia, which often also runs in families. Mesiodentes are usually teeth that are atypically shaped and most often occur due to overproduction of the dental arch. They are peg teeth with a peg-like or cone-like or smooth crown. The root is normally fully formed and not split. Inflammatory processes or pain rarely occur. Mesiodentes break through only in a quarter of cases.
- Paramolars: Additional, single-rooted teeth found mainly in the upper jaw. Paramolars are very often fused to the molar, and a palatal cusp is also formed. Paramolars and distomolars are often peg-shaped teeth, which may fuse with the molars in the root region. Early extraction is required for orthodontic reasons and due to the increased risk of caries.
- Distomolar teeth: Extra teeth that grow behind the wisdom teeth. Distomolars are supernumerary teeth that are usually found in the upper jaw. These push into the oral cavity like the wisdom teeth, but are usually located in the jawbone, preventing tooth eruption.
- Kleidocranial dysplasia: Here, multiple supernumerary tooth systems occur. Typical here is also a defect of the clavicles, which can lead the shoulders very far forward.
- Inauthentic hyperdontia: a permanent tooth breaks through without losing the deciduous tooth.
Symptoms, complaints and signs
In the context of hyperdontia, cysts may occur, also not infrequently there is the dissolution or degradation of the root of adjacent teeth. Different proportions of the lower jaw or upper jaw size as well as an eruption obstruction can also be symptoms. Sometimes there may also be localized tooth crowding or the formation of an unusually enlarged jaw segment. Due to the hyperdontia, normal biting or chewing is not possible. In addition, asymmetries – such as a crossbite – can occur and easily inflammatory dirt niches can develop. Hyperdontia is not always immediately recognizable; it is usually indicated by eruption disorders of permanent teeth.However, a radiological examination or pain can also lead to the discovery of an excess number of teeth. A radiological image of the upper jaw is predominantly used for clarification; in complicated cases, a teleradiograph lateral image can also be used for diagnosis.
Treatment and therapy
As part of therapy, the supernumerary teeth in the maxilla are usually removed if hypertonicity is present, as otherwise a shift in the midline may occur. However, a supernumerary incisor that is normally formed is usually not noticeable and can therefore be left in place if the supernumerary tooth does not cause dental crowding. A mesiodens is normally also removed, as otherwise a gap may develop between the upper central incisors. The teeth should be extracted as early as possible so that a gap can be closed. If there are already damaged teeth near the supernumerary tooth, removal is also recommended. After part of the active treatment period, a holding phase usually follows so that a gap-free row of teeth and a stable bite can be maintained. Plastic splints, removable appliances or so-called lingual retainers, which should be worn for at least one year, are suitable for this purpose. Extraction therapy usually begins around the age of ten. It should be noted that extraction also affects the esthetics or soft tissue profile. Therapy is much more complex if the tooth anomaly is due to a genetic disease.
Prevention
Since the exact causes of hyperdontia are unknown, there is no way to prevent tooth hyperdontia.
Aftercare
In most cases of hyperdontia, there are no or very few aftercare measures available to the affected person. The disease can only be treated to a very limited extent, so the focus here is on early detection with subsequent treatment. The earlier the hyperdontia is detected, the better the further course of this disease usually is. As a rule, hyperdontia does not have a negative effect on the life expectancy of the person affected. In most cases, this disease is treated by surgical intervention in the oral cavity. This should be performed at an early age, so that parents should consult a doctor with their children at the first signs and symptoms. Those affected should rest and take care of their body after such an operation. Effort or stressful activities should be avoided to speed up the healing process. Likewise, the affected person can only eat very soft food at first after the procedure. Only after the wounds have healed can the usual food be resumed. Usually, hyperdontia can be completely cured if it is detected early.