Üç boyutlu yazıcıların şeffaf plak ataşmanlarını baskı doğruluğunun değerlendirilmesi

The aim of this study is to evaluate and compare the accuracy of different attachments' geometries printed by Stereolithography Apparatus (SLA) and Digital light processing (DLP) 3D printing techniques measuring volumetric changes using 3D superimposition analysis. Two Intraoral scans of patients treated at Yeditepe Dental Faculty and Hospital-Department of Orthodontics were selected randomly from the archive and were prepared using the Ortho Analyzer 3D software (3Shape A/S, Copenhagen, Denmark). Six attachments with different geometries were designed using Rhinoceros 3D Software version 7 (Robert McNeel & Associates, Seattle, USA), and were imported to the digital models to form the control group. The models were then printed using two different printers (SLA and DLP). Thereafter, the models were scanned with TRIOS intraoral scanner (3Shape, Copenhagen, Denmark) to result in two digital model sets (each upper and lower, total n=8) according to the printer's type. Each digital model set was divided into six subgroups (study groups) according to the shape of the attachments. The examined attachments were then superimposed to the control group using Geomagic Control X software (3D Systems, South Carolina, USA) to measure the volumetric changes by means of RMS mean. Statistically significant differences between printing techniques were present (p<0.05) with a significantly lesser RMS mean value for the SLA printer. Moreover, significant differences were shown between attachment groups (p<0.05) with the RMS mean of the Ellipsoid group being significantly lower than that of the Horizontal Rectangular and Optimized Rotation groups. SLA printers may be recommended for clear aligners' fabrication. The geometry of the attachments plays a role in the resultant printing accuracy. Along the same, the orientation of the attachments may be more influential. Nevertheless, the final orientation of the attachments in relationship to printing platform is unpredictable as it may be affected by the inclination, rotation and tipping of the teeth on that the attachments were placed, as well as the distance of the attachment to the long axis of the tooth along with the arch curvature. Key Words: three-dimensional printing, clear aligners, clear aligners' attachments, three-dimensional analysis, printing accuracy.