本研究希望了解目前牙科常見的咬合器面弓，其前後參考點的設定是否能準確的轉移台灣人之其實參考水平面(true horizontal reference plane)。實驗內容取用146位台灣人以自然頭顱位置所拍攝成之測顔X光片，於X光片上分別以鼻根點(Nasion)、眶下點(Orbital)以及前牙切緣(Incisal)等常用之咬合器面弓前參考點設定，與耳洞上緣之後參考點設定連成面弓之參考水平面，分析此三種面弓之參考水平面，與法蘭克福水平面(FH plane)及自然頭顱位置(natural head position)之水平面，所形成之角度之差異。結果發現以前牙切緣點向上43mm為前參考點之設定最接近法蘭克福水平面（角度差異-2.92°+3.70°）及自然頭顱位置之水平面（角度差異-2.66°+4.87°）。但以鼻根點向下23mm或顏面部眶下點為前參考點之設定，與法蘭克福水平面及自然頭顱位置水平面，之間角度的標準差較小，表示對於以台灣人為樣本，使用鼻根點或顏面部眶下點為前參考點之設定值，只要略微修正，就有較佳之準確度的潛力。

This study examined which one of the three different anterior reference points do we used in the facebow transfer procedures, accurately transfer the true horizontal reference plane to dental articulator in Taiwanese population. The group of adult Taiwanese 146 (were subjected to cephalometric evaluation were used the Nasion、the Orbital and the Incisal point as the anterior reference point, that was related the Porion point to formed the arbitrary horizontal reference plane. We examined the angles difference between the arbitrary horizontal reference planes and the Frankford plane, and the true horizontal reference plane. In this study, the point above the Incisal point 43 mm as the anterior reference point and formed the horizontal reference plane, was closed to FH plane (angle variation -2.92°+3.70°) and true horizontal reference plane (angle variation-2.66°+4.87°). But the point under Nasion 23mm and the point of facial Orbital as the anterior reference point, have the less variation compared to the Incisal point.