Comparison of marginal accuracy and internal fit of cast nickel chromium and metal laser-sintered crowns: An in vitro study
Priyanka Konin1, Arvind Moldi2, Nagesh Ingleshwar3, Shalini Nawabadkar4, Rajasekhara Subhashini5, Mohamed Ghalib Ruqshan Anjum6
1 Department of Prosthodontics, AME’S Dental College and Hospital, Raichur, Karnataka, India
2 Department of Prosthodontics and Implantology, HKE’S SN Dental College and Hospital, Kalaburgi, Karnataka, India
3 Department of Prosthodontics, HKE’S SN Dental College and Hospital, Kalaburgi, Karnataka, India
4 Department of Oral Medicine and Radiology, Rajiv Gandhi University of Health Sciences, Bengaluru, Karnataka, India
5 Department of Conservative and Endodontics, Bangalore Institute of Dental Science and Hospital, Bengaluru, Karnataka, India
6 Department of Conservative and Endodontics, Aditya Dental College and Hospital, Beed, Maharashtra, India
Dr. Priyanka Konin
Department of Prosthodontics, AME’S Dental College and Hospital, H. No: 6-2-70/50A, Manikprabhu Layout, Raichur 584103, Karnataka.
Source of Support: None, Conflict of Interest: None
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.