Comparative Evaluation of the Marginal and internal adaptation of Metal Copings Fabricated using Conventional Casting, Computer aided Design/ Computer aided Milling and direct Metal Laser Sintering techniques: An invitro study

Author(s): Taranjit Singh Walia, Ravudai singh Jabbal, Fatinderjeet Singh, Sumanjit, ARV Gayathrinath, Lovejeet Ahuja.

Aim: To comparatively evaluate the vertical marginal gap and internal fit of metal copings obtained from the four techniques and to determine the technique that will provide the best marginal accuracy and internal fit for better clinical results.

Material and Method: Forty metal copings will be fabricated using the custom-made metal master die and divided into four groups of ten samples each according to the different fabrication techniques used. The copings from each group will be luted on the metal die using a light viscosity silicone material. Then heavy viscosity silicone material will then be injected on the internal surface and external surface of the light viscosity silicone and sectioned bucco-lingually and observed under a stereomicroscope. Post Hoc Tukey HSD and One-way ANOVA were applied to analysis data.

Results: The mean MG was highest for Group I followed by Group III, Group II and Group IV. The mean internal gap at MAW was highest for Group I followed by Group II, I and III. At AOLA the mean gap was highest for Group III followed by Group I, II and IV. While for the MIS the mean gap was greatest for Group III followed by Group II, IV and I.

Conclusion: Within the limitations of the study, it was concluded that Copings made by using stainless steel ring with DMLS technique had the least marginal gap then other techniques.