Comparison of marginal accuracy and internal fit of cast nickel chromium and metal laser-sintered crowns: An in vitro study

Autor: Arvind Moldi, Priyanka Konin, Rajasekhara Subhashini, Shalini Nawabadkar, Nagesh M Ingleshwar, Mohamed Ghalib Ruqshan Anjum
Rok vydání: 2020
Předmět:
Zdroj: International Journal of Oral Care and Research. 8:74
ISSN: 2347-6249
Popis: Purpose: The aim of this study was to evaluate and compare the marginal accuracy and internal fit of crowns fabricated by direct metal laser sintering, induction casting, and centrifugal casting. Materials and Methods: An acrylic resin analog of the right maxillary first molar was prepared with a total convergence angle of 6° and an occlusal reduction of 1.5 mm and 0.8 mm shoulder finish line. Thirty impressions of the analog tooth were obtained from the definitive die, n = 10 for each group. Wax patterns were fabricated and casting was done using an induction casting machine and centrifugal gas torch method, and for the direct metal laser-sintering group the dies were scanned and crown fabricated using EOS sintering machine. The marginal and internal gaps were estimated by measuring the cement thickness using a stereomicroscope. The mean value was determined and P values were obtained using a one-way analysis of variance (ANOVA) test. Student’s t test was used to determine the differences between the three groups. Results: The mean marginal and internal gaps were 59.82 ± 5.21 μm and118.69 ± 20.23 μm in the direct metal laser-sintering group, 116.13 ± 7.88 μm and 136.94 ± 13.50 μm in induction casting group, and 116.87 ± 7.46 μm and 133.77 ± 10.63 μm in centrifugal casting group, respectively. Conclusion: Under the limitation of this in vitro study, the marginal and internal gaps of DMLS group are better than centrifugal and induction casting groups.
Databáze: OpenAIRE