Median incisor fusion

Abstract

A n unusually rare dental abnormality presented a problem in nomenclature. The condition may be said to be either gemination, fusion, or dichotomy, or a combination of two or more of these three conditions. Gem&&ion is described as an arrangement or combination in pairs, fusion as a blending of different or the same things into one coalition, and dichotomy as a partial or whole division into two parts5 Fig. 1, A illustrates what appears to be an erupted deciduous maxillary central incisor situated in the midline of the anterior maxillary aveolus. Situated directly above the erupted deciduous central incisor and within the maxillary alveolus is observed what appears to be an unerupted maxillary central incisor of the permanent series. In both the deciduous and permanent dentitions the described abnormally placed maxillary central incisors are flanked by normalappearing maxillary deciduous and permanent lateral incisors. The patient, a 5-year-old white boy, had an essentially negative dental and medical history, with no familial history of dental abnormalities. Moorrees4 Garn and associateq2 and Lewis,3 have all undertaken studies pertaining to the mesiodistal width of deciduous and permanent maxillary central incisors in the white male. MoorTees in his study of permanent maxillary central incisors in 87 white male patients found the mean mesiodistal width to be 8.78 mm. Garq2 in his series, measured 103 permanent central incisors in white males and found an average, mesiodistal width of 8.78 mm. Lewis3 in his Burlington series, measured 98 deciduous maxillary right central incisors in white males and found the mean mesiodistal width to be 6.36 mm. He also measured 123 permanent maxillary left and right central incisors and found