A Longitudinal Study on the Growth and Development of the Dental Arch Length from Childhood to Adolescence

Abstract

The purpose of this study was to evaluate the longitudinal changes in the dental arch length from childhood to adolescence. Materials were longitudinal casts taken at 2-month intervals from 28 children (13 males and 15 females) with normal occlusion. Observations were made from 3 years and 6months to 20 years of the chronological age. The dental age was based on the emergence of the permanent central incisor and the exfoliation of the second deciduous molar. The dental arch length was measured as the distance between the labial surface of the left (deciduous or permanent) central incisor and a line connecting the most distal points on the distal surfaces of the second deciduous molars. After the exfoliation of the second deciduous molar, measurements were made on the distance between the labial surface of the left permanent central incisor and a line connecting the most mesial points on the mesial surfaces of the permanent first molars.
Observation by chronological age, revealed that the dental arch length during the period of the deciduous dentition decreased slightly until the exfoliation of the deciduous central incisor in both the maxilla and the mandible. Observation by dental age based on the emergence of the permanent central incisor, revealed that the dental arch length showed a similar decrease until 6 months before the emergence in the maxilla, and until 2 months before the emergence in the mandible, but after that they increased until the exfoliation of the deciduous central.
Observation by chronological age, revealed that the dental arch length after the emergence of the permanent central incisor increased gradually until 11 years of age in the maxilla, and until 10 years of age in the mandible.
Observation by dental age, revealed that the dental arch length increased remarkably until 6 months after the emergence in the maxilla, and until 2 months after the emergence in the mandible. Observation by dental age based on the exfoliation of the second deciduous molar, revealed that the dental arch length decreased remarkably from the exfoliation until 1 year and 6 months after the exfoliation in both the maxilla and the mandible. After that the dental arch length remained nearly stable while showing a tendency to decrease gradually until the time of the last observation.
No statistically significant sex-related differences were observed in the dental arch length in both the maxilla and the mandible.