應用於數位牙模建構之三維掃描研究

3D Dental Scanning for Digital Impression

吳子懷(Tzu-Huai Wu)

指導教授 ： 江青芬

共同指導教授 ： 吳佳祥(Chia-Hsiang Wu)

義守大學/醫學院/生物醫學工程學系/碩士(2019年)

摘要

近年來，三維掃描技術應用於人體備受矚目，有鑒於假牙製程的傳統翻模繁瑣費時，本研究利用三維掃描技術來取得數位牙齒模型，並深入探討不同的三維掃描技術，嘗試改善牙模製程的效益。
本研究先以不同掃描演算法，使用塊規作驗證，再掃描不同材質、尺寸的牙齒模型進行比較評估。本研究使用三種掃描方法分別為「格雷碼掃描」、「混合型三相位移掃描」以及「混合型四相位移掃描」，混合型是指格雷碼掃描方法與相位移掃描方法的結合。
根據單因子變異數分析發現：「混合型四相位移掃描」適合掃描大塊規，「混合型三相位移掃描」適合掃描小塊規。根據雙因子變異數分析結果發現：不同的掃描方法及不同尺寸的塊規皆會對測量準確度造成顯著影響，且此兩個影響因子間有顯著的交互作用。此外，掃描小塊規的精確度比大塊規來得好。另一方面，待掃物的材質也會影響掃描結果，金屬材質的塊規無法掃描成功，塑膠材質的牙模雖然可以掃描成功，但是石膏材質有更細緻的掃描結果。

關鍵字

結構光 ； 投影圖樣 ； 牙模掃描

並列摘要

In recent years, the application of 3D scanning technology in human body has attracted much attention. Because the traditional impression is cumbersome and time consuming, the study tried to improve the effectiveness of the dental impression by using the different 3D scanning techniques.
The study first compared different 3D scanning algorithms and used the block gauges for verification, and then scanned the tooth models of different materials and sizes for comparative evaluation. The three scanning methods used in this study include: "Gray Code Algorithm", "Hybrid Three-Step Phase Shifting Algorithm" and "Hybrid Four-Step Phase Shifting Algorithm". The hybrid type refers to the combination of the gray code algorithm and the phase-shift algorithm.
According to the one-way analysis of variance, the "Hybrid Four-Step Phase Shifting Algorithm" is suitable for large size scanning, while the "Hybrid Three-Step Phase Shifting Algorithm" is suitable for small size. According to the two-way analysis of variance, “scanning” methods and “sizes” have significant effect on the measurement accuracy. These two factors also have significant mutual interaction.
In addition, the accuracy of small-block-gauge measurement is better than that of the big one. Regarding the material, the scanning of metal block gauges tended to fail due to the high reflectance. In contrast, the gypsum material is better than the plastic material for the 3D scanning.

並列關鍵字

Structured Light ； Projected Pattern ； Dental Scan

參考文獻

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