Supernumerary teeth are frequently investigated and many reports have been reported on by different investigators. The majority of these teeth are located in the region of the maxillary incisors and are generally conical or unusual in shape. The number of supernumerary teeth is usually one, the incidence of multiple supernumerary teeth being very low.
Here we shall report on a case of four supernumerary teeth in the maxillary permanent incisor area of a 9-year-old boy. At the first visit, clinical examination revealed the following dental pattern: _??_ (S is supernumerary tooth). X-ray examination disclosed three impacted supernumerary teeth in the maxillary incisor area. One of them had erupted on the palatal side away from the normal aligment. The other three were impacted and inverted in position. One of them was of the so-called "Mesiodens" shape. Their shapes were as follows: two of them were of the three-cone shape; one, of the four-cone shape; and one, of the five-cone shape. The supernumeraries caused delayed eruption of the central permanent incisors. Both lateral permanent incisors had erupted. Immediate extraction of the supernumeraried was indicated. About 50 days after the operation, both incisors had erupted, but their orientation resulted in malocclusion. This patient was placed on follow-up.