The goal of dental esthetic treatment is to restore mastication and esthetics. Dental esthetic treatment differs from prosthodontic treatment due to the fact that the former considers the relationship between the anterior teeth and the entire facial configuration, especially around the mouth, to provide a beautiful smile. Rufenacht, in his textbook “Fundamental of Esthetics” in 1₉₉0, advocated 10 factors to create a beautiful smile. One of the factors states that “The shape of the anterior teeth has to be in Golden Proportion”. Although the factors make sense, the factor regarding the golden proportion raises a question. Hence, we measured the width of the maxillary anterior teeth and compared them to the ʻgolden proportionʼ. A total of 162 Japanese female, with an average age of 31 years old were examined. They were treated by orthodontists who are boardcertified by the Japanese Orthodontic Association. The subjects underwent orthodontic treatment with an initial diagnosis of Angle class 1, ANB2 to 4 malocclusions with no skeletal involvement.Photographs of the maxillary anterior after orthodontic treatment were used for measurements. Three dentists with more than 5 years of clinical experience measured the width of the maxillary anterior from the photos enlarged by 3.8 times. The crown width obtained from the two–dimensional photographs was 32.48 ± 1.01 mm for central incisors, 23.83 ± 0.8₉ mm for lateral incisors, and 1₉.₉0 ± 1.04 mm for cuspids. The average width of central incisor was 1.36 and the cuspid was 0.84 with the lateral incisor as 1. It is common that the width of the tooth increases from lateral incisor followed by the cuspid, and the central incisor. However, the harmony of anterior teeth should not be based on the actual width of each tooth, but on the two–dimensional tooth proportion viewed from the anterior, which can be affected by the shape of the dental arch, the angle of each tooth, and so on. According to our results, the ratio of the central to the lateral incisor did not coincide with the golden ratio of 1:1.618 but rather to the silver ratio of 1: √2 (1.414), a traditional beautiful proportion in Japanese culture. To compare of results, we used the textbook “Anteriores”, by Dr. Jan Hajto and examined the two–dimensional measurement of the maxillary anterior teeth in 32 European female. We concluded that the ideal incisor proportion before and after orthodontic treatment in Asian women is closer to the silver ratio. Even for European female, the ideal incisor proportion is not necessarily the golden ratio, contrary to popular belief