Advisory Committee Chair
Daniel A Givan
Advisory Committee Members
James C Broome
Keith Kinderknecht
Nathaniel Lawson
Perng-Ru Liu
Document Type
Thesis
Date of Award
2016
Degree Name by School
Master of Science in Dentistry (MScD) School of Dentistry
Abstract
Purpose: To determine the precision and accuracy of the True Definition Scanner (3M) (TDS) to capture margins at different gingival heights. Materials and Methods: A typodont with soft gingiva and removable indexed Ivorine® teeth was used. Tooth #19 was prepared to fit an all-ceramic crown with a chamfer margin. Spacers placed beneath the prepared tooth elevated #19 in the typodont and controlled the tooth margin height relative to the gingival margin. The TDS was used as an intraoral scanner. A total of 50 scans were made with 5 groups of 10 scans each. In Group 1 (control) the prepared tooth margin was 1 mm supra- gingival, while in Group 2 the margin equi-gingival. In groups 3 through 5, the margin position was respectively 1, 2, or 3 mm infra-gingival. optical scans were generated following manufacturer’s recommended procedures. The STL files were processed using MeshLab software computer-aided analysis to trim to the tooth #19 margins producing a new output file. The new STL processed and surface area (SA) was measured using Netfabb software. All post-processing was performed by the same operator. Results: The measured SA of the scan groups was evaluated with one-way ANOVA and Tukey’s post-hoc test (p ≤ 0.05) and reveals a statistically significant difference between the groups. Post-hoc testing revealed no statistical difference between iii control group and equi-gingival group but did reveal statistical differences between each of the infra-gingival groups. Conclusion: Optical impressions using the TDS was determined to be reliable in producing precise impressions scans with supra-gingival and equi-gingival margins. However, as the position of the margin was located more infra-gingival, the scans become incomplete and result in loss of accuracy and precision compared to the control.
Recommended Citation
Galindo Ramirez, Ricardo Jose, "Capacity Of The 3M True Definition Scanner To Make Repeatable Impressions Depending On Placement Of Margins In Relation To Gingival Height." (2016). All ETDs from UAB. 1685.
https://digitalcommons.library.uab.edu/etd-collection/1685