Luo Ting, Shi Changrong, Zhao Xing, Zhao Yunsong, Xu Jinqiu
School of Mathematical Sciences, Capital Normal University, Beijing, China.
Beijing Higher Institution Engineering Research Center of Testing and Imaging, Beijing, China.
PLoS One. 2016 Jun 14;11(6):e0156976. doi: 10.1371/journal.pone.0156976. eCollection 2016.
In this paper, we propose an automatic method of synthesizing panoramic radiographs from dental cone beam computed tomography (CBCT) data for directly observing the whole dentition without the superimposition of other structures. This method consists of three major steps. First, the dental arch curve is generated from the maximum intensity projection (MIP) of 3D CBCT data. Then, based on this curve, the long axial curves of the upper and lower teeth are extracted to create a 3D panoramic curved surface describing the whole dentition. Finally, the panoramic radiograph is synthesized by developing this 3D surface. Both open-bite shaped and closed-bite shaped dental CBCT datasets were applied in this study, and the resulting images were analyzed to evaluate the effectiveness of this method. With the proposed method, a single-slice panoramic radiograph can clearly and completely show the whole dentition without the blur and superimposition of other dental structures. Moreover, thickened panoramic radiographs can also be synthesized with increased slice thickness to show more features, such as the mandibular nerve canal. One feature of the proposed method is that it is automatically performed without human intervention. Another feature of the proposed method is that it requires thinner panoramic radiographs to show the whole dentition than those produced by other existing methods, which contributes to the clarity of the anatomical structures, including the enamel, dentine and pulp. In addition, this method can rapidly process common dental CBCT data. The speed and image quality of this method make it an attractive option for observing the whole dentition in a clinical setting.
在本文中，我们提出了一种从牙科锥形束计算机断层扫描（CBCT）数据自动合成全景X线片的方法，用于直接观察整个牙列，而不会有其他结构的叠加。该方法包括三个主要步骤。首先，从三维CBCT数据的最大强度投影（MIP）生成牙弓曲线。然后，基于该曲线，提取上下牙齿的长轴曲线，以创建一个描述整个牙列的三维全景曲面。最后，通过展开这个三维曲面来合成全景X线片。本研究应用了开颌型和闭颌型牙科CBCT数据集，并对所得图像进行分析以评估该方法的有效性。使用所提出的方法，单层面全景X线片可以清晰完整地显示整个牙列，而不会出现其他牙齿结构的模糊和叠加。此外，还可以通过增加层厚来合成加厚的全景X线片，以显示更多特征，如下颌神经管。所提出方法的一个特点是它无需人工干预即可自动执行。所提出方法的另一个特点是，与其他现有方法相比，它需要更薄的全景X线片来显示整个牙列，这有助于提高包括牙釉质、牙本质和牙髓在内的解剖结构的清晰度。此外，该方法可以快速处理常见的牙科CBCT数据。该方法的速度和图像质量使其成为临床环境中观察整个牙列的一个有吸引力的选择。
