[A study of the growth changes of the alveolar arch in Chinese infants]

Sillman, Abe, and Ichilkawa demonstrated that the alveolar arches of infants change with growth and development. They considered that the shape and dimensions of the dental arch will change as the growth of the alveolar arch in infants proceed. They also suggested that recording the growth pattern of the alveolar arch might help us predict the future development of the dental arch. Our material consisted of maxillary and mandibular casts of 164 Kaohsiung infants. It was obtained after pooling the data of studies of Child Dental Growth and Development for research conducted under the direction of Dr. Tien-Yu Shieh of the School of Dentistry, Kaohsiung Medical College. After being examined at the Pediatric Health Center, Chung Ho Memorial Hospital, K.M.C., 106 male infants and 58 female infants from two months to twelve months of age were selected. All individuals were free of abnormalities, chronic disease, or cleft lip and palate. The dimensions of the upper and lower arches were measured with a vernier in combination with other special devices. The growth and developmental curves of the lengths and widths of the alveolar arches were plotted using the means of the alveolar lengths and widths. Results demonstrated that the dimensional coefficients of variance of the anterior alveolar length were greater than those of the other dimensions. The anterior alveolar length varied the most for any given age (in months). The posterior alveolar width and mandibular whole alveolar length showed the least amount of change from two months to twelve months of age. Comparison of the right and left side of the alveolar vector dimension showed no significant difference. It was noted that the alveolar arches of male and female infants grew rapidly. The growth and developmental curves of the alveolar arches of male infants were more steep and rapid than those of female infants. As compared with previous investigations of the Japanese population, the maxillary anterior alveolar lengths and anterior alveolar widths of the present investigation were greater than those of Japanese infants.