Research Associate, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Dental Materials and Biomaterial Research, Berlin, Germany; Department of Dental Surgery, Sechenov First Moscow State Medical University, Moscow, Russia.
Research Associate, Section "Medical Materials and Science", Tuebingen University Hospital, Tuebingen, Germany.
J Prosthet Dent. 2023 Sep;130(3):402-413. doi: 10.1016/j.prosdent.2021.06.050. Epub 2022 Mar 4.
How much skin surface details of facial prostheses can be transferred throughout the digital production chain has not been quantified.
The purpose of this in vitro study was to quantify the amount of skin surface details transferred from the prosthesis virtual design through the prototype printing with various additive manufacturing (AM) methods to the definitive silicone prosthesis with an indirect mold-making approach.
Twelve test blocks with embossed wrinkles of 0.05 to 0.8 mm and 12 test blocks with applied earlobe skin structures were printed with stereolithography (SLA), direct light processing (DLP), and PolyJet methods (n=4). DLP and SLA prototype specimens were duplicated in wax. All specimens were then transferred into medical-grade silicone. R values of the wrinkle test blocks and the root mean square error (RMSE) of the earlobe test blocks were evaluated by laser topography to determine the trueness and precision of each stage.
For the earlobe test blocks, the PolyJet method had superior trueness and precision of the final skin surface reproduction. The SLA method showed the poorest trueness, and the DLP method, the lowest precision. For the wrinkle test blocks, the PolyJet method had the best wrinkle profile reproduction level, followed by DLP and SLA.
The indirect mold-making approach of facial prostheses manufacturing may be associated with 7% of skin surface profile loss with SLA, up to 20% with DLP, and no detail loss with PolyJet.
面部假体的皮肤表面细节在整个数字化生产链中能传递多少，尚未被量化。
本体外研究的目的是量化从假体虚拟设计通过各种增材制造（AM）方法传递到使用间接模制方法制作的最终硅树脂假体的皮肤表面细节量。
使用立体光固化（SLA）、直接光处理（DLP）和 PolyJet 方法打印了 12 个带有 0.05 至 0.8 毫米压纹的测试块和 12 个带有应用耳垂皮肤结构的测试块（n=4）。对 DLP 和 SLA 原型样本进行蜡质复制。然后，将所有样本转移到医用级硅树脂中。通过激光形貌术评估皱纹测试块的 R 值和耳垂测试块的均方根误差（RMSE），以确定每个阶段的真实性和精度。
对于耳垂测试块，PolyJet 方法在最终皮肤表面再现的真实性和精度方面具有优势。SLA 方法的真实性最差，DLP 方法的精度最低。对于皱纹测试块，PolyJet 方法具有最佳的皱纹轮廓再现水平，其次是 DLP 和 SLA。
面部假体制造的间接模制方法可能与 SLA 相关的皮肤表面轮廓损失 7%，与 DLP 相关的损失高达 20%，而 PolyJet 则无细节损失。
