Abstract：
OBJECTIVE: To assess the accuracy of complete maxillary and mandibular edentulous arch scans obtained using two different intraoral scanners (IOSs), with and without scanning aids, and to compare these results to those obtained using conventional impression methods.
METHODS: Two IOSs were used (TRIOS 4 [TRI] and Emerald S [EMR]) to scan maxillary and mandibular typodonts. The typodonts were scanned without scanning aids [TRI_WSA and EMR_WSA groups] (n = 10). The typodonts were then scanned under four scanning aid conditions (n = 10): composite markers [TRI_MRK and EMR_MRK groups], scanning spray [TRI_SPR and EMR_SPR groups], pressure indicating paste [TRI_PIP and EMR_PIP groups], and liquid-type scanning aid [TRI_LQD and EMR_LQD groups]. Conventional impressions of both arches were also made using irreversible hydrocolloids in stock trays [IHC] and using polyvinyl siloxane (PVS) impression material in custom trays (n = 10) which were digitized using a laboratory scanner. Using a metrology software program, all scans were compared to a reference scan in order to assess trueness and to each other to assess precision. Trueness and precision were expressed as the root mean square (RMS) of the absolute deviation values and the statistical analysis was modeled on a logarithmic scale using fixed-effects models to meet model assumptions (α = 0.05).
RESULTS: The main effect of arch (p = 0.004), scanner (p < 0.001), scanning aid (p = 0.041), and the interaction between scanner and scanning aid (p = 0.027) had a significant effect on mean RMS values of trueness. The arch (p = 0.015) and scanner (p < 0.001) had a significant effect on the mean RMS values of precision. The maxillary arch had better accuracy compared to the mandible. The TRIOS 4 scanner had better accuracy than both the Emerald S scanner and conventional impressions. The Emerald S had better precision than conventional impressions. The scanning spray and liquid-type scanning aids produced the best trueness with the TRIOS 4 scanner, while the liquid-type scanning aid and composite markers produced the best trueness for the Emerald S scanner.
CONCLUSIONS: The scanned arch and the type of scanner had a significant effect on the accuracy of digital scans of completely edentulous arches. The scanning aid had a significant effect on the trueness of digital scans of completely edentulous arches which varied depending on the scanner used.
METHODS: Two IOSs were used (TRIOS 4 [TRI] and Emerald S [EMR]) to scan maxillary and mandibular typodonts. The typodonts were scanned without scanning aids [TRI_WSA and EMR_WSA groups] (n = 10). The typodonts were then scanned under four scanning aid conditions (n = 10): composite markers [TRI_MRK and EMR_MRK groups], scanning spray [TRI_SPR and EMR_SPR groups], pressure indicating paste [TRI_PIP and EMR_PIP groups], and liquid-type scanning aid [TRI_LQD and EMR_LQD groups]. Conventional impressions of both arches were also made using irreversible hydrocolloids in stock trays [IHC] and using polyvinyl siloxane (PVS) impression material in custom trays (n = 10) which were digitized using a laboratory scanner. Using a metrology software program, all scans were compared to a reference scan in order to assess trueness and to each other to assess precision. Trueness and precision were expressed as the root mean square (RMS) of the absolute deviation values and the statistical analysis was modeled on a logarithmic scale using fixed-effects models to meet model assumptions (α = 0.05).
RESULTS: The main effect of arch (p = 0.004), scanner (p < 0.001), scanning aid (p = 0.041), and the interaction between scanner and scanning aid (p = 0.027) had a significant effect on mean RMS values of trueness. The arch (p = 0.015) and scanner (p < 0.001) had a significant effect on the mean RMS values of precision. The maxillary arch had better accuracy compared to the mandible. The TRIOS 4 scanner had better accuracy than both the Emerald S scanner and conventional impressions. The Emerald S had better precision than conventional impressions. The scanning spray and liquid-type scanning aids produced the best trueness with the TRIOS 4 scanner, while the liquid-type scanning aid and composite markers produced the best trueness for the Emerald S scanner.
CONCLUSIONS: The scanned arch and the type of scanner had a significant effect on the accuracy of digital scans of completely edentulous arches. The scanning aid had a significant effect on the trueness of digital scans of completely edentulous arches which varied depending on the scanner used.
摘要：
目的：为了评估使用两种不同的口内扫描仪（IOSs）获得的完整上颌和下颌无牙弓扫描的准确性，有和没有扫描辅助设备，并将这些结果与使用常规印模方法获得的结果进行比较。
方法：使用两个IOS（TRIOS4[TRI]和EmeraldS[EMR]）扫描上颌和下颌字节病。在没有扫描辅助工具的情况下扫描排字机[TRI_WSA和EMR_WSA组](n=10)。然后在四种扫描辅助条件(n=10)下扫描打字稿:复合标记[TRI_MRK和EMR_MRK组],扫描喷雾[TRI_SPR和EMR_SPR组]，压力指示膏[TRI_PIP和EMR_PIP组]，和液体型扫描辅助[TRI_LQD和EMR_LQD组]。还在原料托盘[IHC]中使用不可逆水胶体并在使用实验室扫描仪数字化的定制托盘（n=10）中使用聚乙烯基硅氧烷（PVS）印模材料制作了两个拱门的常规印模。使用计量软件程序，将所有扫描与参考扫描进行比较,以评估真实性,并相互比较以评估精确度.真实性和准确性表示为绝对偏差值的均方根（RMS），并且使用固定效应模型在对数标度上对统计分析进行建模以满足模型假设（α=0.05）。
结果：拱的主要作用（p=0.004），扫描仪（p<0.001），扫描辅助（p=0.041），扫描仪和扫描辅助工具之间的相互作用（p=0.027）对平均RMS值的真实性有显着影响。足弓（p=0.015）和扫描仪（p<0.001）对精度的平均RMS值具有显着影响。与下颌骨相比，上颌弓具有更好的准确性。TRIOS4扫描仪比EmeraldS扫描仪和常规印模都具有更好的精度。翡翠S具有比传统的印象更好的精度。扫描喷雾和液体型扫描辅助产生最佳的真实性与TRIOS4扫描仪，而液体型扫描辅助和复合标记为EmeraldS扫描仪提供了最佳的真实性。
结论：扫描的牙弓和扫描仪的类型对完全无牙牙弓的数字扫描的准确性有显着影响。扫描辅助工具对完全无牙牙弓的数字扫描的真实性有显着影响，这取决于所使用的扫描仪。
方法：使用两个IOS（TRIOS4[TRI]和EmeraldS[EMR]）扫描上颌和下颌字节病。在没有扫描辅助工具的情况下扫描排字机[TRI_WSA和EMR_WSA组](n=10)。然后在四种扫描辅助条件(n=10)下扫描打字稿:复合标记[TRI_MRK和EMR_MRK组],扫描喷雾[TRI_SPR和EMR_SPR组]，压力指示膏[TRI_PIP和EMR_PIP组]，和液体型扫描辅助[TRI_LQD和EMR_LQD组]。还在原料托盘[IHC]中使用不可逆水胶体并在使用实验室扫描仪数字化的定制托盘（n=10）中使用聚乙烯基硅氧烷（PVS）印模材料制作了两个拱门的常规印模。使用计量软件程序，将所有扫描与参考扫描进行比较,以评估真实性,并相互比较以评估精确度.真实性和准确性表示为绝对偏差值的均方根（RMS），并且使用固定效应模型在对数标度上对统计分析进行建模以满足模型假设（α=0.05）。
结果：拱的主要作用（p=0.004），扫描仪（p<0.001），扫描辅助（p=0.041），扫描仪和扫描辅助工具之间的相互作用（p=0.027）对平均RMS值的真实性有显着影响。足弓（p=0.015）和扫描仪（p<0.001）对精度的平均RMS值具有显着影响。与下颌骨相比，上颌弓具有更好的准确性。TRIOS4扫描仪比EmeraldS扫描仪和常规印模都具有更好的精度。翡翠S具有比传统的印象更好的精度。扫描喷雾和液体型扫描辅助产生最佳的真实性与TRIOS4扫描仪，而液体型扫描辅助和复合标记为EmeraldS扫描仪提供了最佳的真实性。
结论：扫描的牙弓和扫描仪的类型对完全无牙牙弓的数字扫描的准确性有显着影响。扫描辅助工具对完全无牙牙弓的数字扫描的真实性有显着影响，这取决于所使用的扫描仪。
