Reproducibility of different coping arrangements fabricated by dental micro-stereolithography: Evaluation of marginal and internal gaps in metal copings

Abstract

Background/purpose To evaluate the reproducibility of the marginal and internal gaps of metal copings fabricated using dental micro-stereolithography (μ-SLA), which is an additive manufacturing system. Materials and methods A study cast of abutment tooth 46 was made from type-IV dental stone and was scanned to create a standard triangulation language file. Arrays of one (ORM), three (TRM), and six (SRM) resin copings were then fabricated on the μ-SLA build platform using investment, burnout, and casting ( n = 12). The marginal and internal gaps of these metal copings were measured using a silicone-replica technique with a digital microscope (×160). The data obtained were analyzed using a non-parametric Kruskal–Wallis H test, a post-hoc Mann–Whitney U test, and a Bonferroni correction. Results The mean and standard deviation of the marginal gap for each group were measured and found to be 81.1 and 53.2 μm, 68.3 and 44.8 μm, and 90.3 and 57.7 μm for ORM, TRM, and SRM, respectively. There were no statistical differences in the marginal gaps of the three groups ( p > 0.05). Conclusion The marginal and internal gap of ORM, TRM and SRM groups were considered clinically acceptable.

Survival assessment of fractured porcelain-fused-to-metal crowns surface roughened by sandblasted and repaired by composite resin after in vitro thermal fatigue

“…Etching can also produce clean surfaces and create microretentive areas to increase the bond strength of the etched substrate. 33 Compared with the data in Table 1 , the non-sandblasted MB group demonstrated the highest thermal fatigue failure rate, with a maximum peeling rate of 80%. Thermal fatigue-induced secondary failure rates for B, M, and MB samples were 8%, 16%, and 24%, respectively.…”

Evaluation of the reproducibility of various abutments using a blue light model scanner

“…Previous studies have also shown that blue light model scanners can be used clinically to produce final prostheses. 24 25 26 27 28 29 30 31 Repeatability has been well established, but reproducibility depends on the position and size of the model. 11 20 …”

Evaluation of the effect of abutment preparation angles on the repeatability and reproducibility using a blue light model scanner

“…This stone is scanned using an extra-oral scanner, and prosthesis is then fabricated using the CAD/CAM system. [17][18][19][20][21] In general, an extra-oral scanner is introduced with the methods of a laser model scanner and an optical model scanner. The laser scanner irradiates the target with a line pattern laser and measures the reflected triangulation distance.…”

“…This stone is scanned using an extra-oral scanner, and prosthesis is then fabricated using the CAD/CAM system. 17 18 19 20 21 …”