Document Type
Article
Language
eng
Publication Date
9-2017
Publisher
Elsevier
Source Publication
The Journal of Prosthetic Dentistry
Source ISSN
0022-3913
Abstract
Statement of problem
The die contour can affect the emergence profile of prosthetic restorations. However, little information is available regarding the congruency between a stereolithographic (SLA) die and its corresponding natural tooth.
Purpose
The purpose of this vitro study was to evaluate the shapes of SLA die in comparison with the subgingival contour of a prepared tooth to be restored with a ceramic crown.
Material and methods
Twenty extracted human teeth, 10 incisors, and 10 molars, were disinfected and mounted in a typodont model. The teeth were prepared for a ceramic restoration. Definitive impressions were made using an intraoral scanner from which 20 SLA casts with removable dies were fabricated. The removable dies and corresponding human teeth were digitized using a 3-dimensional desktop scanner and evaluated with computer-aided design software. The subgingival morphology with regard to angle, length, and volume at the buccolingual and mesiodistal surfaces and at zones A, B, C, and D were compared. Data were first analyzed with repeated measures analysis of variance (ANOVA), using locations (buccolingual and mesiodistal), zones (A, B, C, and D), and model type (SLA and Natural) as within-subject factors and tooth type (molar and incisor) as the between-subject factor. Post hoc analyses were performed to investigate the difference between natural teeth and corresponding SLA models, depending upon the interaction effect from the repeated measures ANOVA (α=.05).
Results
For angle analysis, the incisor group demonstrated a significant difference between the natural tooth and SLA die on the buccolingual surfaces (PPPPPP
Conclusions
For the comparison of angles, SLA dies did not replicate the subgingival contour of natural teeth on the buccolingual surfaces of the incisal groups. For the comparison of length and volume, SLA dies were more concave and did not replicate the subgingival contour of natural teeth in the incisal and molar groups.
Recommended Citation
Agrawal, Pratiksha; Thompson, Geoffrey A.; Cho, Seok-Hwan; and Ziebert, Gerald J., "Evaluation of Die Trim Morphology Made by CAD-CAM Technology" (2017). School of Dentistry Faculty Research and Publications. 318.
https://epublications.marquette.edu/dentistry_fac/318
Comments
Accepted version. The Journal of Prosthetic Dentistry, Vol. 118, No. 3 (September 2017): 406-412. DOI. © 2017 Elsevier B.V. Used with permission.