Manufacture accuracy and geometric discrepancy of direct laser sintering versus cast cobalt chromium bars in mandibular implant retained overdenture: an in-vitro comparative study

BACKGROUND: This in vitro study aimed to compare and analysis degree of Manufacture accuracy and geometric discrepancy measurements of Cobalt-Chromium (C0-Cr) bar joint attachment supporting a mandibular complete overdenture fabricated directly by Direct Laser Sintering (DMLS) and indirectly fabricated by conventional casting of 3D printed resin pattern using Co-Cr alloys with the same reference design. METHODS: A total of twelve bar joint attachment for two implant-retained mandibular overdentures were fabricated through additive manufacturing process indirectly by using 3D printed resin pattern and directly by using DMLS (n = six for each group). All the sample specimens of metal bars were scanned and superimposed with the reference STL reference design by using the Geomagic Control X software program. RESULTS: There was no significant statistical difference in manufacture accuracy and geometric discrepancy in the bars fabricated by DMLS compared to indirectly 3D-printed conventional Co-Cr bars in mandibular implant retained overdenture. The Casted group has a mean of 0.1128 ± 0.006, while the DMLS group has a mean of 0.1206 ± 0.01. There was no significant difference between the groups, Regarding Internal Discrepancy, the Casted group shows a mean of 0.1659 ± 0.118, and the DMLS group has a mean of 0.1678 ± 0.035. The research indicates no significant difference between the groups for this variable. CONCLUSION: No significant difference in Manufacture accuracy and geometric discrepancy of direct laser sintering versus cast 3D printed resin pattern of Co-Cr bars in mandibular implant retained complete overdenture.