由2D到3D-談新一代電腦斷層攝影術在矯正治療上的診斷價值

From 2D to 3D-The Orthodontic Diagnostic Value of New Generation of Computed Tomography

黃榆鈞(Yu-Chun Huang) ； 陳木熊(Mu-Hsiung Chen) ； 張瑞青(Jenny Zwei-Chien Chang) ； 賴向華(Eddie Hsiang-Hua Lai) ； 姚宗珍(Chung-Chen Jane Yao) ； 陳羿貞(Yi-Jane Chen)

《中華民國齒顎矯正學雜誌》 20卷4期 (2008/12) Pp. 4-15

https://doi.org/10.30036/TJO.200812.0001

摘要

優質的醫用影像對於矯正醫師在臨床的工作上，可以提供大量的診斷資訊，而現今因為錐狀射束斷層掃描儀的發展，我們可以藉此得到顱顏部的三維立體影像，對病人而言，其相較於傳統斷層掃描，有較低的花費，較少的輻射暴露時間與劑量等優點，所以現今在臨床的應用範圍及使用時機都與日俱增。在本文中，我們回顧了斷層掃描儀的發展，也比較數種應用在拍攝顱顏部影像的儀器之輻射劑量，同時整理了錐狀射束斷層攝影的臨床應用範圍。在現今市面上常見的錐狀射束斷層掃描儀其輻射劑量的範圍是36.9-476.6μSv，換算約為6-79張的數位環口X光片的劑量，這個劑量範圍上的差異主要原因是來自於不同的機型，和拍攝範圍大小的差異。而錐狀射束斷層掃描儀在矯正的應用上，現在主要是利用其三維影像的優點，用來評估包括阻生齒的定位、顳顎關節形態的觀察、上呼吸道系統的評估、在做上顎撐寬前，評估頰側齒槽骨的寬度，以及正顎手術治療計畫的擬定與結果的預測等等。這些更完備的資訊，將更為有助於提升臨床診斷的正確性。

關鍵字

治療計畫 ； 3D ； 斷層掃描 ； 錐狀射束斷層掃描

並列摘要

The development of cone beam computed tomography (CBCT) offers more information to orthodontist as a diagnostic modality. CBCT can provide accurate 3D images of human body even in craniofacial area, with lower cost, shorter exposure time, and less radiation than conventional CT. These advantages have gained increasing popularity and expanded its clinical application range. In this article, we reviewed the history and development of computed tomography, comparison of the radiation dose among different types of equipments, including CBCT, for dental maxillofacial imaging, and the clinical application of CBCT. It was reported that the radiation dose of CBCT was 36.9-476.6 μSv and equaled to 6-79 times of digital panoramic radiograph. The wide range is due to different machine and different size of FOV. CBCT is widely applied in orthodontics for 3-D assessment, including the location of impacted tooth, morphology of TMJ, morphology of upper respiratory system, evaluation of the width of alveolar bone plate before maxillary arch expansion, treatment planning and prediction of orthognathic surgery.

並列關鍵字

treatment plan ； 3D ； CT ； cone-beam CT