Xie Q, Soikkonen K, Wolf J, Mattila K, Gong M, Ainamo A
Department of Prosthetic Dentistry, University of Helsinki, Finland.
Dentomaxillofac Radiol. 1996 Apr;25(2):61-6. doi: 10.1259/dmfr.25.2.9446974.
To assess whether it is possible to make accurate vertical measurements of the jaws from panoramic radiographs.
Five dry skulls were shifted 5 mm forwards and backwards and tilted 5 degrees up and down in the sagittal plane. Panoramic radiographs of each skull were obtained in nine different positions. In the maxilla, three reference lines were used and vertical measurements were made at the distal surfaces of the first premolar and first molar and in the midline. In the mandible, measurements were made at the distal surfaces of the first premolar and first molar, and at the mental foramen on both sides, and in the midline. The points and lines were marked manually and the radiographs were digitized, magnified and measured.
Sagittal shifting and tilting had only a slight effect on measurements in the mandible. Sagittal tilting of the head had the greatest effect on all the measurements made from the line between the articular eminences to the alveolar crest, as well as measurements in the maxillary midline.
The line between the articular eminences is unsuitable as a reference line for measurements of the tooth-bearing areas. A slight misalignment of the head does not significantly affect the vertical measurements in the mandible or of the posterior maxilla if the reference lines are in the same vertical plane as the teeth.
评估能否通过全景X线片对颌骨进行准确的垂直测量。
将五个干燥颅骨在矢状面内向前和向后移动5毫米，并上下倾斜5度。在九个不同位置获取每个颅骨的全景X线片。在上颌骨，使用三条参考线，并在第一前磨牙和第一磨牙的远中面以及中线处进行垂直测量。在下颌骨，在第一前磨牙和第一磨牙的远中面、两侧的颏孔以及中线处进行测量。手动标记点和线，并将X线片数字化、放大并测量。
矢状面移位和倾斜对下颌骨测量的影响较小。头部矢状面倾斜对从关节结节到牙槽嵴的连线所做的所有测量以及上颌骨中线处的测量影响最大。
关节结节之间的连线不适宜作为测量牙列区的参考线。如果参考线与牙齿在同一垂直平面内，头部轻微的不对准不会显著影响下颌骨或上颌骨后部的垂直测量。
