Akademik Veri Yönetim Sistemi
European Association of Osseointegration (EA=), Milan, İtalya, 24 Ekim 2024, cilt.35, sa.3, ss.4-6, (Tam Metin Bildiri)
Background
Although the use of elastomeric impression materials is still considered the gold standard for dental impressions, intraoral scanning seems to have several advantages, including increased patient and operator satisfaction, reduced time and the ability to digitally store and retrieve information
In dental implant treatments the conventional open or closed impression techniques have some limitations. In these methods, tightening the screws of the impression posts, especially in the molar region, may pose a problem in individuals with limited mouth opening. Additionally, taking impressions using silicone impression materials may not be appropriate in individuals with nausea reflexes, mobile teeth and trismus. In such cases, digital intraoral impression systems can provide more effective and precise measurements than traditional methods.
The use of digital impressions in implant treatment shortens the treatment time by giving a highly accurate data.
Aim
The aim was to assess and compare the trueness of 16 different IOSs and 3 different laboratory scanners and conventional impression in 3D printed model containing 4 implants with different angulations.
The aim of this study is to assess if the oral scanners are more accurate than the conventional impression techniques or not. To determine which oral scanner system is more accurate than the others.
Material and Method
Intraoral impressions (STL) and CBCT (DICOM) data were obtained from open source of National Library of Medicine (NLM, 2023) which was a mandibular partial edentulism case used for implant planning and producing a surgical guide by using implant planning software (coDiagnostiX). The master referenced model (MRM) was obtained by placing implants in accordance with this planning in the 3D printed model. According to the FDI nomenclature, the implant number 35 was placed in a straight position, number 36 in a 20° lingual inclined position, number 45 in a 10° buccal inclined position, and number 46 in a straight position. The reference scan was obtained by scanning the main model with an ATOS Q scanner. 16 different IOS (3Shape Trios5, 3Shape Trios3 Move Plus, 3Shape Trios3, 3Shape Trios4, BenQ BIS-1, Carestream 3600, Heron IOS, iTero Element 2, iTero Element 5 HD, iTero Lumina, Medit i500, Medit i700, Omnicam, Primescan, Virtuo Vivo, Virtuo Vivo POD) and 3 different Lab Scanners (3Shape E3, Dental Wings 7Series, Sirona inEos X5) and 10 impressions were obtained using open and closed tray impression techniques. All scans were performed under appropriate conditions by a prosthodontist (E.D.) with at least 2 years of experience. Scans were made in accordance with the scanning strategy of IOS brands. These measurements were compared with the reference measurement using Zeiss Inspect 2023 (GOM) software. The degree of variance among groups of experimental scans was calculated for precision (distance and angular deviation). First, a flat plane was generated on the top surfaces of the scan bodies both in the MRM scan (nominal) and in the test model scans. Parallel and 3 mm below these planes, two circles, one in nominal and one in test scans were generated. This is to create standard circles for all scans and impressions. Subsequently, the linear deviations of these two circles in x, y, and z directions were calculated.
The average deviation amounts were determined by overlapping the sets. The data obtained were analyzed using the Kruskal-Wallis test and Mann-Whitney U.
It was evaluated statistically using tests. Statistical significance level was determined as p<0.05.
Results
There is a significant difference between the groups in terms of 35,36,45 and 46 scan bodies dXYZ values (p <0.05). Lab Scanners values are significantly lower than other groups.
There is a significant difference in terms of angular deviation(AD) values (p <0.05). Lab Scanners values are significantly lower than other groups. IOS values are also significantly lower than the Conventional group. (Table1)
There is a significant difference between the groups in terms of dXYZ and Angle values in all scanbodies (p <0.05).
At number 35, 3Shape E3, Dental Wings 7Series, Sirona inEos X5, iTero Element 2, Primescan, Heron IOS, 3Shape Trios3 and Carestream 3600 scanners gave better results than the other scanners in terms of dXYZ values as they were closer to 0. The 3Shape E3 and Virtuo Vivo POD scanners gave better results than the other scanners in terms of Angle values, as they were closer to 0. (Table2)
At number 36, 3Shape E3, Dental Wings 7Series, Sirona inEos X5, iTero Element 2, Primescan, 3Shape Trios3 and Carestream 3600 scanners gave better results than the other scanners in terms of dXYZ values as they were closer to 0. The Virtuo Vivo POD and Sirona inEos X5 scanners gave better results than the other scanners in terms of Angle values, as they were closer to 0. (Table2)
At number 45, 3Shape E3, Dental Wings 7Series, 3Shape Trios3, Carestream 3600, Sirona inEos X5, Primescan, iTero Element 2, Medit i700, 3Shape Trios4, 3Shape Trios3 Move Plus, Medit i500 and Omnicam scanners gave better results than the other scanners in terms of dXYZ values as they were closer to 0. The 3Shape E3, Medit i700 and Sirona inEos X5 scanners gave better results than the other scanners in terms of Angle values, as they were closer to 0. (Table2)
At number 46, Dental Wings 7Series, iTero Element 2, 3Shape Trios3, Carestream 3600, Sirona inEos X5, Primescan and 3Shape E3 scanners gave better results than the other scanners in terms of dXYZ values as they were closer to 0. The Medit i700 and Dental Wings 7Series scanners gave better results than the other scanners in terms of Angle values, as they were closer to 0. (Table2)
The data obtained in this study were analyzed using SPSS 22 package program. Since the data were not normally distributed, Mann-Whitney U test was used for two-group comparisons and Kruskal-Wallis H test was used for comparisons with three or more groups. 0.05 was used as the significance level and it was stated that there was a significant difference in case of p<0.05 and there was no significant difference in case of p>0.05.
Conclusion and Clinical implications
In this in vitro study, digital scanners were compared to traditional methods and within the limitations of this study, digital intraoral impression systems will be a good alternative to traditional impression systems.
Accuracy results revealed that IOS technique better than conventional technique significantly to reduce distance deviation (P <0.05) and angular deviation.
Lab Scanners deviate significantly less than other groups. However, it should not be forgotten that models obtained from conventional impression are used in this measurement method.
No significant deviations were observed in the scans of implants placed in an angled position compared to straight ones.
In this study, IOS scans were always started from the left side. Some IOS showed an increase in dXYZ and Angle deviations towards the right side of the arch which proves the research findings of some studies which stated that accuracy decreases as scan data increases.
This in vitro study and many other studies have shown that digital scanners now give as successful results as conventional methods.The reproducibility of intraoral scanners, except for their precision, seems to be clinically adequate for the moment. More studies are required for the clinical use of digital intraoral scanners. Especially the lack of in-vivo studies creates a big gap in the literature. The accuracy of Lab Scanners is sufficient and reliable both clinically and statistically.
Keywords: Intra oral scanners, accuracy, lab scanners, dental implant impression methods, angular deviations, distance deviations