929 D3000 new imprint Word template Vol 13, No 1 (2025) ISSN 2167-8677 (online) DOI 10.5195/d3000/2025.929 http://dentistry3000.pitt.edu Digital Versus Conventional Impressions Mohammad Munthir Abdulrazzaq, Mithaq R. Mohammed College of Den*stry, Al-Iraqia University, Baghdad, Iraq Abstract Objec9ve: The purpose of this research was to compare, in vivo, the three-dimensional (3D) dental impressions produced by digital and tradiNonal methods. Material and Methods: This research was comprised of ten individuals who had full natural teeth. The subjects' molars were digitally imprinted using an intra-oral scanner (Helios 600 3D). The double-mix impres- sion method (SILAXIL BOX & PROTESIL LIGHT) was also used to create a silicone imprint. The Lava COS system exported the stereolithography (STL) data immediately, and a three-dimen- sional (3D) intra-oral scanner recorded the STL data of a plaster model created from a silicone imprint. The 3D assessment program captured the STL files. It overlaid them using the best- fit-algorithm approach for each impression technique (least-squares method, PolyWorks, In- novMetric program). The Wilcoxon signed-rank test was used to compare the two methods with respect to 3D data. Results: Differences between digital impressions were less noNcea- ble when comparing them to silicone impressions, according to a visual analysis of stacked datasets. Using a digital imprint approach yielded more confirmaNon (0.014± 0.02 mm) com- pared to a tradiNonal method (0.023 ± 0.01 mm). Conclusion: According to this in vivo inves- NgaNon, digital impression technology outperforms tradiNonal ompression techniques. Open Access Cita%on: Abdulrazzaq MM, et al. (2025) Digital Versus Conven%onal Impressions. Den%stry 3000. 1:a001 doi:10.5195/d3000.2025.929 Received: May 3, 2025 Accepted: May 31, 2025 Published: June 27, 2025 Copyright: ©2025 Abdulrazzaq MM, et al. This is an open access ar%cle licensed under a Crea%ve Commons APrib- u%on Work 4.0 United States License. Email: Mohamad_monther@aliraqia.edu Introduc)on "Digital Dentistry" is rapidly expanding and represents a major shift in the dental indus- try that is occurring this century. The use of three-dimensional (3D) intra-oral scanners for digital impressions has recently been trending upward in popularity globally [1]. Dental prostheses may be immediately de- signed and manufactured using digital pic- tures of the dental arches and occlusal con- nections recorded by these intra-oral scan- ners [2–5]. There are several reasons why in- tra-oral scanners might eventually replace traditional impression materials [6–10]. For instance, as compared to traditional impres- sion methods, its implementation stream- lines processes and increases transparency throughout the impression operation, bene- Kiting patients, dental technicians, and den- tists alike [4,5,11,12]. Since dental stone grows due to secondary reactions and sili- cone impression materials are prone to di- mensional changes due to ongoing chemical reactions, this approach also eliminates mis- takes associated with the standard impres- sion technique. An ill-Kitting dental prosthe- sis might be the consequence of such altera- tions in dimensions. On the other hand, these kinds of alterations should not be expected when teeth are scanned digitally. Several in vitro investiga- tions have shown that digital impressions are far more accurate and precise in terms of dimensions than traditional impressions [11,13–18]. Unfortunately, there are several clinical aspects that might affect the impres- sion's accuracy and precision. The only way to determine accuracy is to compare results, ideally against a gold standard, which is dif- Kicult to do in the mouth. There is a dearth of high-quality in vivo research when it comes to accuracy [19,20]. Consequently, the 3D morphological data ob- tained by digital imprint techniques was the primary focus of this work, which contrasted these data with those obtained in vivo through more traditional methods. Material and Methods The ten individuals who were a part of this research were dentistry students at our Digital Versus ConvenNonal Impressions Vol 13, No 1 (2025) DOI 10.5195/d3000/2025.929 http://dentistry3000.pitt.edu 2 institution and had full natural teeth (5 men and 5 females; average age 22.6±2.0 years). An intra-oral scanner and silicone imprint material are the two methods we use. There was a total of twenty impressions. Digital Impression Digital impressions were created using an in- tra-oral scanner (Helios 600 3D). Following the guidelines provided by the manufac- turer, a digital optical scan was carried out in a single uninterrupted operation, beginning at the occlusal surface and progressing to the lingual and buccal surfaces. The information retrieved from the digital scanning process was sent straight from the Lava COS system to the lab computer (Figure 1). Figure 1. Helios 600 3D Device. Conventional Impression We used a twofold mix impression method and ordinary metal stock trays to make whole arch conventional impressions using vinylpolysiloxane silicone (SILAXIL BOX & PROTESIL LIGHT). We made sure there was enough room for the impression material. After the appropriate tooth was Killed with light-type imprint material using a syringe, the tray was placed in the mouth and pushed against the tooth arch. The imprints were taken out of the mouth after the setting pe- riod, cleaned for 10 minutes, and then let sit at room temperature and humidity for 3 hours. After following the manufacturer's in- structions (Kig. 2&3), dental stone plaster models were scanned using an intra-oral scanner (Helios 600 3D). Data from the scans of the premolar and molar areas were saved on the lab's computer using the STL data for- mat. Figure 2. Convensional impression (mandibular cast). Figure 3. Conventional impression (maxil- lary cast). Analysis of 3D Data The tooth form and gingival margin were ad- justed in the 3D images created from STL data using the right software (PolyWorks, In- novMetric Software). Before being overlaid utilizing the best-Kit-algorithm approach (least-squares method) to match 2 surfaces, these trimmed STL data were put into a 3D assessment software platform [17,20]. The STL dataset was designated as the standard. With the help of the reference data set's tri- angular surfaces and the test data set's poly- gons, the program determines the orienta- tion and nearest distance of each vertex. The industrial sector makes frequent use of this veriKication approach [21–23]. For two methods, we averaged the absolute value disparities in overall measurement lo- cations. On top of that, we determined the mean difference across all 10 individuals. Evaluation of the Casts Scanner and In- traoral Scanner in vitro The accuracy of the scanner, which might af- fect the accuracy of the scanned data, was tested by scanning a cast model Kive times and comparing the resulting ten data set pairings using the best-Kit algorithm, as men- tioned before. The oral scanner underwent the same tests in a controlled environment to ensure accuracy. Statistical Analysis We used the Mann-Whitney U test to com- pare the two methods by calculating the av- erage disparities of all measurement points. A 0.05 threshold of signiKicance was used. Because the data did not follow a normal dis- tribution, non-parametric Mann-Whitney U tests were used to determine if there was a statistically signiKicant difference between the digital and traditional imprint methods. An analysis was conducted using SPSS ver- sion 22 (SPSS Inc., Chicago, IL, USA) for sta- tistical purposes. Results To compare the two methods, this research used digital and conventional imprint tech- niques for dental work. For both methods, precise readings were taken for several pa- rameters (ten in all). Parameters like "a," "b," and "c" have much lower mean values and variability metrics for the Digital Impression Technique compared to the Conventional Impression Technique, indicating improved accuracy. A statistically signiKicant difference in meas- urement accuracy between the digital im- pression method and the traditional impres- sion technique is shown by the substantially higher mean value of parameter "a" in the former (p=0.000) compared to the latter. With a p-value of 0.000, there is a difference in the results for parameter "b," as the tradi- tional imprint method has a much lower mean value than the digital impression ap- proach. With a p-value of 0.000, parameter "c" shows that the traditional impression ap- proach tends to provide larger measure- ments than the digital impression technique, with the former showing a higher mean value. Parameters "j" and "i", on the other hand, do not change signiKicantly between methods (p=0.917 and p=0.117) (Figure 4). Most cases of generalized aggressive disease were observed in patients with the condition (60%), compared to 30% of people who have chronic or localized severe periodontitis. The case group tended to have higher levels of bleeding, plaque, and gingivitis. This dis- parity did not, however, reach statistical sig- niKicance. In comparison to non-users, case women had mean probing depths that were deeper (3.3–1.0 versus 2.7–0.5 mm) (P = 0.04) (Table 2 and Figure 2). Discussion These Kindings imply that digital impressions have less disparity than traditional impres- sions. In contrast to more traditional imprint meth- ods, digital direct scanning has several estab- lished advantages, as mentioned in the intro- duction. Despite claims to the contrary, digi- tal impressions are prone to errors because of factors including saliva, jaw movement, Digital Versus ConvenNonal Impressions Vol 13, No 1 (2025) DOI 10.5195/d3000/2025.929 http://dentistry3000.pitt.edu 3 and the merging of many digital pictures. The fact that digital impressions are not sus- ceptible to the inevitable mistakes caused by the dimensional changes of dental stones and impression materials, which may result in the misKitting of dental prostheses, is one of the most signiKicant advantages from a clinical standpoint. Digital impressions outperform traditional impressions in vitro in terms of dimensional correctness and precision, according to many studies [11, 13–17]. It is crucial to con- duct in vivo clinical assessments to prove the translation of in vitro Kindings to clinical im- portance in vivo because several clinical cir- cumstances affect the accuracy and precision of an impression. Unfortunately, the gold standard (ISO 5725-1) [24]—accuracy, which stands for truthfulness—cannot be readily tested in patients' mouth cavities, making it impossible to assess in vivo. It is common practice to measure the Kit of Kinal restorations as a means of conducting in vivo accuracy assessments [3,7,20,25,26]. Com- paring restorations made using digital im- pressions to those made using traditional impressions, studies have shown that the former provides a more clinically acceptable Kit [6,27-30]. It should be mentioned that these assessments of accuracy include the complete restoration manufacturing pro- cess, not only the imprint operation. Conse- quently, it is necessary to compare the im- print processes. To determine the accuracy of an imprint technique, it is recommended to repeatedly superimpose full scanned pictures taken in the same way [16,17,20,31]. Using the calcu- lated 3D distances, this process Kinds the dis- crepancies between the impression pictures taken at each surface point. The clinical fea- sibility of such a comparison is high. How- ever, the number of investigations assessing the accuracy of the imprint method in vivo is low [19,32]. Previous work [19] that the digital imprint systems had adequate precision in vivo. There is broad consensus among our re- search Kindings. Because silicone impres- sions are so sensitive to the clinician's com- petence and experience level, the latter is es- pecially crucial from a clinical standpoint [10,12]. Our research found that 3D data from direct oral digital scanning is far more consistent than data from silicone impres- sions, which is an important Kinding. Given the scanner's proven accuracy and precision in previous studies, it stands to reason that dimensional variations in the materials used to make stone models from silicone imprints might be a contributing factor to their incon- sistency [20,33–37]. Please be aware that the focus of our re- search was not on accuracy but on precision as applied to individual clinical cases. Table 1 shows that digital impressions were con- sistently and independently more reproduc- ible than silicone impressions, regardless of participant. This suggests that the inherent dimensional changes associated with the sil- icone impression technique may be the main factor inKluencing this Kinding. Finally, our results indicate that the digital impression approach provides higher accu- racy, even if the average variation between the two methods was just 0.009 mm, which is not deemed clinically important. 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