UNASSIGNED: Six different thermoplastic materials with different initial thicknesses were used for aligner thermoforming using Biostar® device (Biostar®, SCHEU-DENTAL GmbH, Iserlohn, Germany). Also, two different dental resins were used to create the printed aligners in three digitally designed thicknesses using IZZI Direct printer (3Dtech, Zagreb, Croatia). The aligners were measured using an electronic micrometer (ELECTRONIC UNIVERSAL MICROMETER, Schut Geometrical Metrology, Groningen, The Netherlands, accuracy: 0.001 mm) on a total of 20 points per aligner. Statistical analysis was performed using the JASP program (JASP, University of Amsterdam, Amsterdam, The Netherlands).
UNASSIGNED: The difference between the thermoformed and printed groups was statistically significant. Significant differences between different thermoformed materials and between 3D-printed materials were found. The thickness of thermoformed aligners deviated more in the upper jaw, whereas the thickness of printed aligners deviated more in the lower jaw. Both differences were statistically significant. The greatest average deviation from the initial thickness was found in Duran 0.75; Erkodur 0.6; Erkoloc-Pro 1.0; IZZI 0.5; NextDent 0.6 and NextDent A 0.6. NextDent group had the lowest deviations for all teeth of both jaws, except for upper and lower first molar where NextDent A group was more accurate.
UNASSIGNED: Thermoformed aligners showed decreased values, while printed ones showed mostly increased values compared to the original material thickness. The highest mean deviation belonged to IZZI group, and the NextDent group had the lowest mean deviation. The thickness of both aligners was thinner at the edges compared to the thickness at cusps and fissures.
■六种具有不同初始厚度的不同热塑性材料用于使用Biostar®设备(Biostar®,SCHEU-DENTALGmbH,Iserlohn,德国)。此外,使用IZZIDirect打印机(3Dtech,萨格勒布,克罗地亚)。使用电子测微计(电子通用测微计,Schut几何计量学,格罗宁根,荷兰,精度:0.001毫米),每个对准器总共20个点。使用JASP程序(JASP,阿姆斯特丹大学,阿姆斯特丹,荷兰)。
■热成型组和印刷组之间的差异具有统计学意义。发现不同热成型材料之间以及3D打印材料之间存在显着差异。热成型矫正器的厚度在上颌中偏差更大,而印刷对准器的厚度在下颌中偏差更大。两者差异均具有统计学意义。在Duran0.75中发现了与初始厚度的最大平均偏差;Erkodur0.6;Erkoloc-Pro1.0;IZZI0.5;NextDent0.6和NextDentA0.6。NextDent组的双颌所有牙齿的偏差最小,除了上,下第一磨牙,NextDentA组更准确。
■热成型矫正器显示出下降的值,与原始材料厚度相比,印刷的材料显示出大部分增加的值。最高的平均偏差属于IZZI组,NextDent组的平均偏差最低。与尖点和裂缝处的厚度相比,两个对准器的边缘处的厚度较薄。