Hubungan Rasio Panjang-Lebar Terhadap Perimeter Lengkung Gigi Rahang Atas Pada Anak Suku Jawa Usia 11-14 Tahun dengan Relasi Oklusi Normal( Kajian Pada Siswa SMP N 15 Yogyakarta )

Dental arch perimeter is one of the dental arch dimensions that are important for presenting the curve form. It can be predicted based on the length and width of dental arch. The aim of this study was to determine the relationship between ratio of the length-width of maxillary dental arch with the perimeter of maxillary dental arch in Javanese children ages 11-14 years old with normal occlusion. This cross sectional study had been done on 30 students of Junior High School (SMP N 15 Yogyakarta), which consisted of 14 boys and 16 girls. Dental arch length, width, and perimeter was measured on the maxillary dental models using a sliding caliper with accuracy of 0,05 mm. The data obtained were statistically analyzed using t-test, correlation, quadratic regression test. The results showed that there was positive significant relationship (p<0,05) between ratio of the length-width of maxillary dental arch with the perimeter of maxillary dental arch in boys (r=0,78) and girls (r=0,76). The regression formula showed equation y= -219,86 + 893,27x - 616,34x² with the coefficient of determination (R²) 0.614 in boys, and y = -1054,92 + 3175,67x - 2176,25x² with R² 0,57 in girls. It can be concluded that the greater ratio of the dental arch length-width, the greater dental arch perimeter. The contribution of the variable ratio dental arch length-width on the variable dental arch perimeter is 61% in boys and 57% in girls.