One abnormal variation of the patient’s dentition, that can effect the occlusion, is supernumerary teeth or extra teeth. The etiology of supernumerary teeth is not known but it may be due to patient’s genetics in tooth bud formation.
Supernumerary teeth can develop in the primary or permanent dentition and in any area of the mouth. In the general population, it’s prevalence is about 1% for primary teeth and 2% for permanent teeth. With permanent teeth, the prevalence of supernumerary teeth is found more in males than females.
Categories of Supernumerary Teeth
Supernumerary teeth are classified into four groups based on their shape: Supplemental, tuberculate, conical and odontoma (Compound and Complex).
Supplemental supernumerary teeth are found in a normal sequence of the dentition. They look just like their counterpart and are usually an extra lateral incisor, premolar or molar. The picture above shows a patient has an supplemental supernumerary lateral incisor. In this case, the orthodontist can choose which tooth is removed then close the space with braces. This patient had a large overjet due to the extra lateral incisor.
Tuberculate supernumerary teeth are rare, bilateral pairs, and have two or more prominent cuspids.
Conical supernumeraries are identified by the crown being shaped like a cone. A mesiodens is a conical supernumerary tooth found in the upper midline that can impede the eruption of the maxillary central incisors.
Compound odontoma are multiple supernumerary teeth that look like small teeth grouped together.
Complex odontomas is a mass of tooth structure of enamel, dentin and cementum that doesn’t look like normal teeth.
When an orthodontist does an examination of the mouth, we look to see if there are some teeth that should have erupted, and have not given the child’s age. The picture above is of a nine year old and the maxillary central incisors should have erupted by this age. The radiograph below is hard to read, but there are two supernumerary teeth that are keeping the central incisors from erupting.
Treatment of Supernumerary Teeth
Primary and permanent supernumerary teeth can change the eruption of other teeth. In most cases, the supernumerary keeps other teeth from erupting causing an impaction. The treatment of a supernumerary tooth is removal. Then, it is determined if orthodontic treatment is needed to help the impacted tooth to erupt.
An oral surgeon will extract the supernumerary tooth or teeth. Then, after the supernumerary is removed, they will place a bracket on the impacted tooth. A wire chain is attached to the bracket and the gum tissue heals with the chain coming out of it. With the braces, the orthodontist can use the wire and elastics to pull the impacted tooth into proper position.