對於62個上捱齒列，我們參考傳統湯普森牙弓形態學的描述，初步給予分類後，根據參考點、線、角度在先前的主成份分析法中作了探討，並且在向量極座標系統中，說明了特徵向量與前牙的曲度，犬齒前突及牙弓圓滑度，牙弓的長寬比，呈現正比的相關，在現今對於上捱齒列形態特徵的探討中，我們引入了傅立葉分析法研討先前所得的數據，我們發現第二、三、四個傅立葉諧波的振幅與牙弓長寬比，前牙區的曲度，及上捱牙弓的曲線外形，有著極密切的關係。
此外，在先前的評估數據和傅立葉分析法中的一系列振幅和常數值間的關係，我們又用了相關分析法的相關系數（P＜0.01）予以檢驗。在現今這個研討的結果，顯示出上捱齒列包含三個要素：牙弓長寬比、前牙區的曲度及牙弓的曲線外形。

Our previous principal component analysis conducting on reference points, lines and angles, and a vector-developed polar coordinate system has elucidated that the components of eigenvectors had positive relationships in the curvature of anterior teeth segment, between the protrusion of canines and degree of arch roundness, and in the length-to-width ratio of 62 maxillary dentitions, which were preliminarily classified with reference to the conventional Thompson’s morphological descriptions for dental arch forms. In the present study on morphological characters of the maxillary dentitions, we conducted a Fourier analysis on the previously obtained data. We observed that the amplitude of 2nd, 3rd and 4th Fourier harmonics were closely correlated with the length-to-width ratio, curvature of the anterior teeth segment, and the curvilinear contour of maxillary dental arches. In addition, the relationships between previously estimated data and the constant value and the amplitude of the Fourier series were examined by analysis of correlation coefficients (p<0.01). The results of the present study suggest that the morphology of maxillary dentitions consists of three essentials –the length-towidth ratio, the curvature of anterior teeth, and the curvilinear contour of dental arches–.