將牙醫訓練中的牙齒修磨(tooth preparation)練習與虛擬實境結合，打造一套教學輔助系統，以輔助用標準假牙模型進行修磨練習的傳統方式。由於牙齒修磨為不可復原之操作，學生很難針對相同的部位重複練習，操作時使用的牙科手機鑽頭(Bur)與牙齒模型皆為耗材，需要定期更換，而且練習時需要使用人頭模型等大型機具來進行輔助，使學生練習的方式與場所受到限制。因此，透過將傳統的牙齒修磨練習過程數位化，並在虛擬實境中重現，學生能針對不熟的部分重複操作，並減少耗材消耗與練習場所的限制。

然而，進行牙齒修磨的練習時，相當依賴手機的形狀觸感與操作時的手部支撐回饋，為了在虛擬實境中模擬真實操作的手感，利用智慧手套、自製數位牙科手機來捕捉操作時的手部動作，透過藍芽即時傳輸，讓使用者的動作在虛擬實境中呈現，3D列印牙齒模型則用來給予手指的支撐的回饋。同時，整合AR、Leap Motion來協助使用者與虛擬實境互動，而牙齒修磨需要較為精細的操作，操作範圍小，使用電腦視覺的方式定位容易因操作的角度受到遮擋，因此選用精度高且能夠避免遮擋問題的磁力定位，捕捉牙科手機的細微移動。

在傳統教學過程，學生在完成練習後，會需要老師來協助判斷修磨結果的好壞，並提供學生建議與該修正的部分，為了讓學生在自主練習後，也能針對修磨的結果給予回饋，本研究與專業的醫師討論後，設計一套評分機制，來判斷練習過程與修磨結果是否符合標準，並提示錯誤的部分，讓學生練習後能自我評量。

Combine virtual reality with the training of tooth preparation to create a teaching aid system. Currently, student prepared tooth in denture model that mounted on manikin with handpiece and other instruments to assist, so they can only paractice at a certain place. Additionally, tooth preparation is an irreversible operation, therefore students are hard to practice repeatedly and those denture model are consumable. In order to solve those problem, we create a system that simulate tooth preparation in virtual reality with less instrument. Student can praction at home and will not waste any real denture model.

When doing tooth preparation, the haptic feedback to very important. In our system, we use Smart Glove 、 self-made digital handpiece to capture user's motion and transimit those data through Bluetooth for real time display user's motion. 3D printing tooth model and vibration motor are used to provide finger rest and give feedback when preparing tooth. Because tooth preparation requires high accuracy, and operate in small region, traditional computer vision based tracking method need to handle occlusion problem may not suitable for this. In our system, we use magnetic positioning technique that without occlusion problem and provide high accuracy.

In dental education, student need instructor to help evaluate the performance and give feedback, this may take long time. To give student feedback of their work instantly, we provde a grading system to evaluate the work and indicate the error part, so that they can self-assess after practice. Additionally, the system can record the procedure of teacher and replay in virtual reality, so student can watch and learn.

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