An In Vitro Study Of Accuracy Of Different Implant Impression Techniques And Impression Materials

Purpose:The aim of this study was to evaluate the effect of different impression techniques and impression materials on the accuracy of implant impressions by sanners.Materials and Methods:The master model was a partially edentulous model with 2implant analogues.The master model was digitized with a high-precision inEos X5scanner used as control groups(n=5).According to three different intraoral scanners(IOS),the experimental groups were divided into three groups(n=5):Trios~?group,CS 3600~?group and CEREC~?AC Omnicam group.According to three different impression techniques(Open Tray with Splint,OT-S?Open Tray with Nonsplint,OT-NS,Closed Tray,CT),two impression materials(Polyether,PE?Polyvinyl Siloxane,PVS)and whether pouring gypsum,the experimental groups were divided into six female mold groups(n=5):OT-S+PE group,OT-S+PVS group,OT-NS+PE group,OT-NS+PVS group,CT+PE group,CT+PVS group,and six male mold groups(n=5):OT-S+PE group,OT-S+PVS group,OT-NS+PE group,OT-NS+PVS group,CT+PE group,CT+PVS group.Each sample of experimental groups were digitized with inEos X5 scanner.All datasets of control groups and experimental groups were loaded into 3-matic 10.0 software(Materialise,Belgium)where measured the whole three-dimensional linear distance deviation values(dR)and angular deviation values(?).comparing the effect of different impression techniques and impression materials on the accuracy of implant impressions among female mold groups,and so do male mold groups.Comparing the effect of different impression techniques and impression materials on the accuracy of implant impressions between female mold groups and male molds.A SPSS19.0 statistical software was used to analyze,and the level of test?=0.05.Results:In dR values,Trios~?had the smallest value(0.17±0.05 mm),followed by CS 3600~?(0.27±0.19 mm)and CEREC~?AC Omnicam(0.59±0.29 mm).Significant differences were found between Trios~?and Cerec Omnicam~?(P<0.05).In?values,no statistically significant differences were found among three groups(P>0.05).The analysis results of dR and?values showed that impression techniques had significant effect on the accuracy of implant impressions(P<0.05),but impression materials had no significant effect(P>0.05).In dR values,there were statistically significant differences between OT-S group(0.34±0.16 mm)and CT group(0.50±0.11 mm)(P<0.05).In?values,there were statistically significant differences between OT-S group(2.08±0.87°)and CT group(2.79±0.86°)(P<0.05).In male mold groups the analysis results of dR values showed that impression techniques had significant effect on the accuracy of implant impressions(P<0.05),but impression materials had no significant effect(P>0.05).In dR values,there were statistically significant differences between OT-S group(0.23±0.12 mm),OT-NS group(0.27±0.14mm)and CT group(0.44±0.18 mm)(P<0.05).There was no significant difference between the first two groups(P>0.05).In male mold groups,the analysis results of?values showed that impression techniques and impression materials had no significant effect on the accuracy of implant impressions(P>0.05).The analysis results of female mold groups and male mold groups with paired t-test showed that there were statistically significant differences in?values of both CT+PVS female mold groups and male mold groups(1.00±1.18°)and CT+PE female mold groups and male mold groups(0.78±0.95°)(P<0.05).No statistically significant differences were found in other groups.Conclusion:1.Obviously,the accuracy of the three-dimensional model data obtained by different intraoral scanner is different.Compared with CEREC~?AC Omnicam group,Trios~?scanner shows better accuracy of implant impressions.2.Impression techniques had significant effect on the accuracy of implant impressions.The clinician can use the impression technique of open tray with splint to improve the accuracy of implant impressions.3.Two impression materials had no significant effect on the accuracy of implant impressions.4.The accuracy of male mold groups were better than the accuracy of female mold groups when using the impression technique of close tray.The accuracy of male mold groups was similar to female mold groups when using the impression technique of open tray.