Comparative in vitro study of the accuracy of impression techniques for dental implants: Direct technique with an elastomeric impression material versus intraoral scanner

Abstract

BackgroundThe aim of this study was to compare a conventional technique (elastomeric impression material - EIM) and a digital technique (scanner digital model – SDM) on a six-analog master model (MM) to determine which was the most exact.Material and MethodsTwenty impressions were taken of a master model (EIM) and twenty scanned impressions (SDM) (True Definition). A coordinate measuring machine (CMM) was used to measure the distances between adjacent analogues (1-2, 2-3, 3-4, 4-5, 5-6), intermittently positioned analogues (1-4, 3-6) and the most distal (1-6). Reference values were established from the master model, which were compared with the two impression techniques. The significance level was established as 5% (p<0.05).ResultsThe precision of each technique was compared with MM. For adjacent analogues (1-2), no significant differences were found between EIM-MM (p=0,146). For intermittently positioned analogues (1-4), SDM did not show significant differences with MM (p=0.255). For the distance between distal analogues (1-6), significant differences were found between both techniques and MM (p=0.001).ConclusionsIn a clinical situation with < three implants, EIM is more exact than SDM, but in cases of four implants SDM is more exact. For rehabilitations (> four implants), neither technique can be considered accurate although error falls within the tolerance limits established in the literature (30-150µm). Key words:Digital workflow, full arch scan, intraoral scanner, CAD/CAM, polyether impression, accuracy.

Digital vs Conventional Implant Impressions: A Systematic Review and Meta‐Analysis

“…Ultimately, 10 articles representing completely edentulous impressions (9 in vitro studies and 1 clinical study) and 8 articles representing partial edentulous impressions (6 in vitro and 2 clinical studies) met the inclusion criteria and were included in the descriptive analysis. One clinical 12 study and 4 in vitro 21‐24 studies from the completely edentulous and one clinical 11 and one in vitro 25 study from the partially edentulous group were excluded from the meta‐analysis, which included 11 studies overall. Excluded studies 26‐62 and reasons for exclusion are shown in Table 1.…”

“…Ten studies 12,21‐24,63‐67 evaluated completely edentulous jaws with 2 to 8 implants, while 8 studies 11,13,25,68‐72 investigated situations with a partially edentulous arch with two or more implants.…”

“…The majority of completely edentulous studies evaluated the accuracy of True Definition (3M ESPE, St Paul, MN) IOS (n = 6), 12,21,23,24,64,65 followed by Trios (3shape, Copenhagen, Denmark) (n = 5), 22,23,63,66,67 and Cerec Omnicam (Dentsply Sirona, Bensheim, Germany) (n = 1) 65 . Two studies 23,65 evaluated 2 intraoral scanners.…”

“…On the other hand, 5 completely edentulous studies 12,21‐23,67 related to the maxilla. One completely edentulous study 24 did not specify arch at all, one partial arch study 13 did not specify arch but reported posterior regions and one 11 included both posterior regions and mandible.…”

Bond strength of lithium disilicate after cleaning methods of the remaining hydrofluoric acid

“…This need for precision is related to the finding that there is a ten-time lower implant mobility compared to the mobility of natural teeth (2). However, all impression methods available today, both conventional and digital, are inevitably prone to errors, which readily explains the high number of studies in this area (4)(5)(6). At closer inspection, nearly all of the investigations addressing this problem are limited to model-based in-vitro setups.…”