2018 Volume 56 Issue 4 Pages 460-465
The prevalence of supernumerary teeth has been estimated to range from 1-5% and those frequently occur in the maxillary incisor region. A previous report found that it is rare for monozygotic twins to have different numbers of supernumerary teeth. We examined monozygotic twin brothers and found that the number of supernumerary teeth in them was different. The patients had their initial examination for an extra tooth at the age of 6 years 0 months old. The older brother was seen first, then two days later the younger brother came to our hospital for an examination. Panoramic radiography findings showed that the older brother had three supernumerary teeth, while the younger had two. Following diagnosis, we decided to extract the teeth in each patient under nitrous oxide inhalation sedation with local anesthesia. The postoperative course of each patient was uneventful. Since the patients were monozygotic twins, involvement of environmental and genetic factors was considered. We concluded that the differences in number, form, situation, and direction of the affected teeth may have been the result of not only genetic and environmental, but also epigenetic factors.
