Trueness Of Intraoral Scanners Research Articles

Effect of different intraoral scanners and post-space depths on the trueness of digital impressions.

The trueness of intraoral scanners (IOSs) has been evaluated in many clinical situations. However, the tests of their performance when scanning post-space preparations are still lacking. The aim of the present study was to compare the trueness of the digital impressions of post spaces with different depths, captured by means of different IOSs. Digital impressions of teeth (N = 16) with post spaces of depths of 8 mm and 10 mm were captured. Three IOSs were used, including Primescan AC, Medit i500 and CS 3600. The STL files were compared to the files obtained from the traditional impression scanning performed with an InEos X5 desktop scanner. Then, reverse engineering software measured the trueness values, which were analyzed using the two-way analysis of variance (ANOVA), followed by Tukey's post-hoc test. The significance level was set at p < 0.05. Significant differences were found between the scanners in terms of root mean square (RMS) values (p < 0.001). The highest RMS value was found for CS 3600 (0.30 ±0.11 mm), followed by Primescan AC (0.26 ±0.09 mm), while the lowest value was found for Medit i500 (0.18 ±0.05 mm). The 8-millimeter-deep post spaces had a significantly higher RMS value than the 10-millimeter-deep ones (0.28 ±0.10 mm and 0.21 ±0.09 mm, respectively) (p = 0.009). The Medit i500 scanner showed the highest post-space digital impression trueness as compared to Primescan AC and CS 3600. In the digital impressions captured with CS 3600, the 10 mm postspace depth had higher trueness than the 8 mm depth. Moreover, CS 3600 was less able to capture the full length of both the 8 mm and 10 mm post-space depths than Primescan AC and Medit i500.

Assessing the Effect of Interimplant Distance and Angle on Different Impression Techniques

We aimed to evaluate the trueness of digital and conventional impression techniques based on different angles and distances between implants and the deviation caused by the angle and distance parameters varying between implants. Eight implants were placed in a polyurethane edentulous mandibular model at different angles and distances. After obtaining a 3-dimensional (3D) reference model by using an optical scanner, the model was scanned with three intraoral scanners: Cerec Omnicam (DO), Trios 3 (DT), and Carestream 3500 (DC). Then, the master casts obtained from the conventional impressions (C) were also digitized, and all impression data were imported into reverse engineering software to be compared with the 3D reference model. Distance and angle measurements between adjacent implants were performed, and the data were analyzed with ANOVA–Tukey and Kruskal Wallis tests. The significance level was accepted as p &lt; 0.05. While DT and C groups gave the best results for high interimplant distances, the trueness of intraoral scanners was found to be superior to the conventional method between closer implants. At higher angulations, the angular trueness of C group was found to be significantly lower. At short distances, digital groups showed superiority, and the trueness of conventional impression decreased with higher angulations.

In Vitro Comparison of the Accuracy of Conventional Impression and Four Intraoral Scanners in Four Different Implant Impression Scenarios.

The aim of this study was to compare the trueness and precision of four intraoral scanners (IOSs) and splinted open-tray conventional implant impression (SOCI) in partial and total edentulism. Four gypsum models (Model A-implants at mandibular right second molar, right second premolar, and right canine; Model B- implants at mandibular right canine, left central incisor, and left canine; Model C-implants at mandibular right second molar, right second premolar, right canine, left central incisor, and left canine; and Model D-implants at mandibular right second molar, right second premolar, right canine, left central incisor, left canine, left second premolar, and left second molar) were prepared, and four different IOSs (Aadva IOS, CS 3600, Trios 3, and Emerald) and one polyvinyl siloxane (PVS) were used. Reference models were digitized with a high-resolution industrial scanner, and data were superimposed. Root mean square (RMS) values were calculated by software and defined as deviation values after superimposition. The oneway analysis of variance (ANOVA) test and Tukey honest significant difference (HSD) test were performed to analyze the data (P < .05). For Models A and B, the truest impressions were made with Aadva, followed by CS 3600, PVS, Trios 3, and Emerald, respectively, while for Model C, the truest impressions were made with CS 3600, followed by Aadva, PVS, Trios 3, and Emerald, and for Model D, the truest impressions were made with Aadva, followed by CS 3600, PVS, Emerald, and Trios 3 (P < .05). There was no statistical difference between groups for precision in Models A, B, and C (P > .05); however, PVS showed lower precision values than other groups in Model D (P < .05). In partial edentulism, IOSs are true and precise as SOCI except Emerald. However, the trueness of IOSs is not favorable in total edentulism cases. SOCI with PVS in total edentulism treated with implants is less precise than IOSs.

Trueness of Intraoral Scanners in Implant-Supported Rehabilitations: An In Vitro Analysis on the Effect of Operators' Experience and Implant Number.

(1) Background: Intraoral scanners (IOS) are widely used in prosthodontics. However, a good trueness is mandatory to achieve optimal clinical results. The aim of the present in vitro study was to compare two IOS considering the operator’s experience and different implant clinical scenarios. (2) Methods: Two IOS (IT—Itero, Align Technology; and OP—Opera MC, Opera System, Monaco) were compared simulating three different clinical scenarios: single implant, two implants, and full-arch rehabilitation. Ten scans were taken for each configuration by two different operators (one expert, one inexperienced); influence of operator experience and the type of scanner used was investigated. (3) Results: Trueness of the scans differed between the experienced and non-experienced operator and this difference was statistically significant in all the three scenarios (p = 0.000–0.001, 0.037). A significant difference was present between the scanners (p = 0.000), in the two-implant and full-arch scenarios (p = 0.00). (4) Conclusions: Experience of the operator significantly affect trueness of IT and OP scanners. A statistically significant difference was present among IOS in the two-implant and full-arch scenarios.

A novel in vivo method to evaluate trueness of digital impressions

BackgroundIntraoral scanners are devices for capturing digital impressions in dentistry. Until now, several in vitro studies have assessed the trueness of digital impressions, but in vivo studies are missing. Therefore, the purpose of this study was to introduce a new method to assess trueness of intraoral scanners and digital impressions in an in vivo clinical set-up.MethodsA digital impression using an intraoral scanner (Trios® 3 Cart wired, 3Shape, Copenhagen, Denmark) and a conventional alginate impression (Cavex Impressional®, Cavex, Haarlem, the Netherlands) as clinical reference were made for two patients assigned for full mouth extraction. A total of 30 teeth were collected upon surgery after impressions making. The gypsum model created from conventional impression and extracted teeth were then scanned in a lab scanner (Activity 885®, SmartOptics, Bochum, Germany). Digital model of the intraoral scanner (DM), digital model of the conventional gypsum cast (CM) and those of the extracted natural teeth (NT) were imported to a reverse engineering software (3-matic®, Materialise, Leuven, Belgium) in which the three models were registered then DM and CM were compared to their corresponding teeth in NT by distance map calculations.ResultsDM had statistically insignificant better trueness when compared to CM for total dataset (p = 0.15), statistically insignificant better trueness for CM when mandibular arches analyzed alone (p = 0.56), while a significantly better DM trueness (p = 0.013) was found when only maxillary arches were compared.ConclusionsOur results show that digital impression technique is clinically as good as or better than the current reference standard for study models of orthognathic surgery patients.