Marginal and internal fit of cobalt-chromium fixed dental prostheses generated from digital and conventional impressions.
Objectives. Digital impressions are increasingly used and have the potential to avoid the problem of inaccurate impressions. Only a few studies to verify the accuracy of digital impressions have been performed. The purpose of this study was to compare the marginal and internal fit of 3-unit tooth supported fixed dental prostheses (FDPs) fabricated from digital and conventional impressions. Methods. Ten FDPs were produced from digital impressions using the iTero system and 10 FDPs were produced using vinyl polysiloxane (VPS) impression material. A triple-scan protocol and CAD software were used for measuring and calculating discrepancies of the FDPs at 3 standard areas: mean internal discrepancy, absolute marginal gap, and cervical area discrepancy. The Mann-Whitney U test was used for analyzing the results. Results. For conventional and digital impressions, respectively, FDPs had an absolute marginal gap of 147  μ m and 142  μ m, cervical area discrepancy of 69  μ m and 44  μ m, and mean internal discrepancy of 117  μ m and 93  μ m. The differences were statistically significant in the cervical and internal areas (P < 0.001). Significance. The results indicated that the digital impression technique is more exact and can generate 3-unit FDPs with a significantly closer fit compared to the VPS technique.
Department of Prosthetic Dentistry/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 12 F, P.O. Box 450, 40530 Gothenburg, Sweden.
Per
0000-0003-4698-3092
P
Svanborg
Department of Prosthetic Dentistry, University of Oslo, 0161 Oslo, Norway.
Henrik
H
Skjerven
Department of Prosthetic Dentistry/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 12 F, P.O. Box 450, 40530 Gothenburg, Sweden.
Pablo
P
Carlsson
Department of Prosthetic Dentistry, Postgraduate Dental Education Center, P.O. Box 1126, 70111 Örebro, Sweden ; School of Health and Medical Sciences, Örebro University, 70281 Örebro, Sweden.
Alf
0000-0001-9240-5053
A
Eliasson
Department of Prosthetic Dentistry/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 12 F, P.O. Box 450, 40530 Gothenburg, Sweden.
Stig
S
Karlsson
Department of Prosthetic Dentistry/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 12 F, P.O. Box 450, 40530 Gothenburg, Sweden.
Anders
A
Ortorp