Supernumerary teeth in upper palate of 15-year-old boy.
Hyperdontia of unknown etiology. These extra teeth are what is known as paramolar - “along the molar”. This means that they didn’t erupt behind the regular teeth, but alongside them. In this case (and a large percentage of molar hyperdontia cases), the supernumerary teeth erupted buccally to the maxillary molars - that is, they erupted on the cheek-facing side of the upper molars. These extra teeth on the outside of the maxilla forced the normal molars inwards, and those are the teeth that you see on the hard palate of this boy.
Most hyperdontia cases never even erupt, and are only visible on x-rays. In cases where the extra teeth do erupt, the most common presentation is a mesiodens - a malformed peg-like tooth between the maxillary central incisors (the upper front teeth). This boy’s case was noted by the author as highly unusual not only for the number of supernumerary teeth, but for the fact that there were multiple forms of extra teeth presented. The presentation of tuberculate (barrel-shaped) and supplemental (the same shape as the teeth in the series) teeth was denoted as a very uncommon occurrence.
Surgery and Diseases of the Mouth and Jaws. Vilray Papin Blair, 1917.