Marginal discrepancy dimensions of single unit metal crowns fabricated by using CAD-CAM–milled acrylate resin polymer blocks or a conventional waxing technique
| Autor: | Daniel Dunham, Van Ramos, Frederick A. Rueggeberg, John S. Brousseau, Jeffrey A. Hodd, David Lalande |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Chamfer
Materials science business.product_category medicine.medical_treatment Acrylic Resins Glass ionomer cement Magnification 02 engineering and technology Crown (dentistry) 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Buccal Surface medicine Composite material Acrylic resin Analysis of Variance Acrylate Crowns 030206 dentistry 021001 nanoscience & nanotechnology chemistry Dimensional Measurement Accuracy visual_art visual_art.visual_art_medium Computer-Aided Design Die (manufacturing) Gold Oral Surgery 0210 nano-technology business |
| Zdroj: | The Journal of Prosthetic Dentistry. 119:948-953 |
| ISSN: | 0022-3913 |
| DOI: | 10.1016/j.prosdent.2017.07.019 |
| Popis: | Statement of problem Because crowns with open margins are a well-known problem and can lead to complications, it is important to assess the accuracy of margins resulting from the use of a new technique. Currently, data regarding the marginal fit of computer-aided design and computer-aided manufacturing (CAD-CAM) technology to fabricate a complete gold crown (CGC) from a castable acrylate resin polymer block are lacking. Purpose The purpose of this in vitro study was to compare marginal discrepancy widths of CGCs fabricated by using either conventional hand waxing or acrylate resin polymer blocks generated by using CAD-CAM technology. Material and methods A plastic model of a first mandibular molar was prepared by using a 1-mm, rounded chamfer margin on the entire circumference of the tooth. The master die was duplicated 30 times, and 15 wax patterns were fabricated by using a manual waxing technique, and 15 were fabricated by using CAD-CAM technology. All patterns were invested and cast, and resulting CGCs were cemented on their respective die by using resin-modified glass ionomer cement. The specimens were then embedded in acrylic resin and sectioned buccolingually. The buccal and lingual marginal discrepancies of each sectioned portion were measured by using microscopy at ×50 magnification. Data were subjected to repeated measures 2-way ANOVA, by using the Tukey post hoc pairwise comparison test (α=.05). Results The factor of “technique” had no significant influence on marginal discrepancy measurement (P=.431), but a significant effect of “margin location” (P=.019) was noted. The confounding combination of factors was found to be significantly lower marginal discrepancy dimensions of the lingual margin discrepancy than on the buccal side by using CAD-CAM technology. Conclusions The marginal discrepancy of CAD-CAM acrylate resin crowns was not significantly different from those made with a conventional manual method; however, lingual margin discrepancies present from CAD-CAM–prepared crowns were significantly less than those measured on the respective buccal surface. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect