scholarly journals Complete-Arch Accuracy of Four Intraoral Scanners: An In Vitro Study

Healthcare ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 246
Author(s):  
Giordano Celeghin ◽  
Giulio Franceschetti ◽  
Nicola Mobilio ◽  
Alberto Fasiol ◽  
Santo Catapano ◽  
...  
Keyword(s):  
Reference Model ◽  
In Vitro Study ◽  
Reference Points ◽  
Dental Arch ◽  
Arch Model ◽  
Linear Measurements ◽  
Stl File ◽  
Digital Reference ◽  
Digital Impressions

The purpose of this study is to define the accuracy of four intraoral scanners (IOS) through the analysis of digital impressions of a complete dental arch model. Eight metal inserts were placed on the model as reference points and then it was scanned with a laboratory scanner in order to obtain the reference model. Subsequently, the reference model was scanned with four IOS (Carestream 3600, CEREC Omnicam, True Definition Scanner, Trios 3Shape). Linear measurements were traced on an STL file between the chosen reference points and divided into four categories: three-element mesiodistal, five-element mesiodistal, diagonal, and contralateral measurements. The digital reference values for the measurements were then compared with the values obtained from the scans to analyze the accuracy of the IOS using ANOVA. There were no statistically significant differences between the measurements of the digital scans obtained with the four IOS systems for any of the measurement groups tested.

scholarly journals Linear Accuracy of Full-Arch Digital Models Using Four Different Scanning Methods: An In Vitro Study Using a Coordinate Measuring Machine

2020 ◽  
Vol 10 (8) ◽  
pp. 2741 ◽  
Author(s):  
Young Hyun Kim ◽  
Sang-Sun Han ◽  
Yoon Joo Choi ◽  
Chang-Woo Woo
Keyword(s):  
Coordinate Measuring Machine ◽  
In Vitro Study ◽  
Dental Arch ◽  
Accuracy Evaluation ◽  
Arch Model ◽  
Linear Measurements ◽  
Scanning Method ◽  
True Model ◽  
Measuring Machine

Improving the accuracy of the digital model is essential for the digitalization of the dental field. This study introduced a novel method of objective accuracy evaluation of digitized full dental arch model using coordinate measuring machine (CMM). To obtain a true linear measurement value using the CMM, 17 reference balls were attached to the typodont, and 12 measurements between balls on the X-(width), Y-(length), and Z-axes (height) were performed automatically. A rubber impression and a plaster cast replica of the typodont with balls were fabricated, and they were digitized with following methods: (a) true model intraoral scans; (b) impression cone-beam computed tomography (CBCT) scans; (c) cast CBCT scans; and (d) cast extraoral scans. Each scanning method was performed 20 times. Twelve linear measurements on the digitized models were automatically made using software. The one-sample t-test and one-way analysis of variance were used for measurement accuracy analysis. The cast extraoral scan was most accurate on X- and Y-axes, while impression CBCT was the most accurate on Z-axis. Over all axes, the intraoral scan resulted in the most deviation from the true model, and the reproducibility of each scan was also low. Extraoral scan shows high precision on width and length, and impression CBCT is advantageous for dental work where height factor is of importance.

scholarly journals Efficient palatal expansion with a quadhelix appliance: an in vitro study using an experimental dental arch model

2011 ◽  
Vol 34 (4) ◽  
pp. 442-446
Author(s):  
Y. Honme ◽  
M. Motoyoshi ◽  
A. Shinohara ◽  
T. Shigeeda ◽  
N. Shimizu
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Dental Arch ◽  
Arch Model ◽  
Palatal Expansion

scholarly journals Influence of Preparation Design, Marginal Gingiva Location, and Tooth Morphology on the Accuracy of Digital Impressions for Full-Crown Restorations: An In Vitro Investigation

2020 ◽  
Vol 9 (12) ◽  
pp. 3984
Author(s):  
Selina A. Bernauer ◽  
Johannes Müller ◽  
Nicola U. Zitzmann ◽  
Tim Joda
Keyword(s):  
In Vitro Study ◽  
Arch Model ◽  
Finish Line ◽  
Posterior Teeth ◽  
Mean Values ◽  
Digital Impressions ◽  
In Vitro Investigation ◽  
Abutment Teeth ◽  
3D Printed

(1) Background: Intraoral optical scanning (IOS) has gained increased importance in prosthodontics. The aim of this in vitro study was to analyze the IOS accuracy for treatment with full crowns, considering possible influencing factors. (2) Methods: Two tooth morphologies, each with four different finish-line designs for tooth preparation and epi- or supragingival locations, were digitally designed, 3D-printed, and post-processed for 16 sample abutment teeth. Specimens were digitized using a laboratory scanner to generate reference STLs (Standard Tessellation Language), and were secondary-scanned with two IOS systems five times each in a complete-arch model scenario (Trios 3 Pod, Primescan AC). For accuracy, a best-fit algorithm (Final Surface) was used to analyze deviations of the abutment teeth based on 160 IOS-STLs compared to the reference STLs (16 preparations × 2 IOS-systems × 5 scans per tooth). (3) Results: Analysis revealed homogenous findings with high accuracy for intra- and inter-group comparisons for both IOS systems, with mean values of 80% quantiles from 20 ± 2 μm to 50 ± 5 μm. Supragingival finishing lines demonstrated significantly higher accuracy than epigingival margins when comparing each preparation (p < 0.05), whereas tangential preparations exhibited similar results independent of the gingival location. Morphology of anterior versus posterior teeth showed slightly better results in favor of molars in combination with shoulder preparations only. (4) Conclusion: The clinical challenge for the treatment with full crowns following digital impressions is the location of the prospective restoration margin related to the distance to the gingiva. However, the overall accuracy for all abutment teeth was very high; thus, the factors tested are unlikely to have a strong clinical impact.

scholarly journals Influence of Scanning-Aid Materials on the Accuracy and Time Efficiency of Intraoral Scanners for Full-Arch Digital Scanning: An In Vitro Study

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2340
Author(s):  
Hyun-Su Oh ◽  
Young-Jun Lim ◽  
Bongju Kim ◽  
Myung-Joo Kim ◽  
Ho-Beom Kwon ◽  
...  
Keyword(s):  
Treatment Group ◽  
Reference Model ◽  
Statistical Significance ◽  
In Vitro Study ◽  
3D Analysis ◽  
Linear Measurements ◽  
Time Efficiency ◽  
Scanning Time ◽  
Scanned Image

This study was performed to verify the influence of scanning-aid materials on the accuracy and time efficiency of full-arch scanning with intraoral scanners. The full-arch reference model was constructed by a 3D printer and scanned with a model scanner to obtain the reference dataset. Four experimental groups (application of ScanCure (SC-80, ODS Co, Incheon, Korea), IP Scan Spray (IP-Division, Haimhausen, Germany) and Vita Powder Scan Spray (Vita Zahnfabrik, Stuttgart, Germany), and no treatment) were designed, and the scans were executed (trueness, n = 5) using two intraoral scanners: I500 (Medit Co., Seoul, Korea) and TRIOS (3shape, Copenhagen, Denmark). All acquired scan data were compared with the reference datasets using the 3D superimposition method and 2D linear measurements. In the 3D analysis, intragroup data were compared with each other (precision, n = 10). Time efficiency was also verified by comparing the scan times of the four experimental groups. In the 3D analysis, the root mean square (RMS) value of the precision of the scanned image was statistically significantly more accurate in the scanning-aid agent-treated groups than in the no-treatment group (p < 0.05). However, the RMS values of trueness and the types of scanning-aid materials were not significantly different. In the 2D measurements, the increased scan distance generated a greater distance deviation. The working time was significantly shorter in the scanning-aid agent groups than in the no-treatment group, with statistical significance (p < 0.05). Therefore, in clinical situations, the application of scanning-aid materials is recommended to reduce scanning time and more efficiently obtain the full-arch scanned image.

scholarly journals In Vitro Study Regarding the Biomechanical Behaviour of Bone and Periodontal Splints I.Model validation

2019 ◽  
Vol 56 (4) ◽  
pp. 1013-1020
Author(s):  
Raluca Maria Vieriu ◽  
Oana Tanculescu ◽  
Florentina Mocanu ◽  
Sorina Mihaela Solomon ◽  
ioan Gabriel Sandu ◽  
...  
Keyword(s):  
Bone Resorption ◽  
In Vitro Study ◽  
Dental Arch ◽  
Bone Strain ◽  
Arch Model ◽  
Mandibular Bone ◽  
Different Types ◽  
The Subject ◽  
Two Stages

This paper is part of a larger study that aims to evaluate the biomechanical behaviour of mandibular bone and periodontal splinting systems subjected to different occlusal forces by means of electric resistive tensometry (ERT). The research was based on the following premise: the degree of bone resorption and periodontal type of splint influence the deformation of the mandibular bone. The study was conducted in two stages: first, the validation of the mandibular dental arch model, which is the subject of the present article, and second, the evaluation of mandibular bone strain in case of different types of bone loss and periodontal splints, which is the subject of a second article.

scholarly journals Accuracy of Proximal and Occlusal Contacts of Single Implant Crowns Fabricated Using Different Digital Scan Methods: An In Vitro Study

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2843
Author(s):  
Xi Ren ◽  
Keunbada Son ◽  
Kyu-Bok Lee
Keyword(s):  
Reference Model ◽  
In Vitro Study ◽  
Data Capture ◽  
Vitro Study ◽  
Occlusal Contact ◽  
Stl File ◽  
Contact Points ◽  
Direct Data ◽  
Single Implant

The purpose of this in vitro study was to compare the accuracy of the proximal and occlusal contacts of single implant crowns fabricated with four data capture methods. The resin models were mounted on an articulator, digitized using a laboratory scanner, and saved as a standard tessellation language (STL) file to serve as the master reference model (MRM). Two different intraoral scan body (ISB) systems were evaluated: polyetheretherketone (PEEK) short scan body (SSB) and PEEK long scan body (LSB) (n = 12). The digital impressions (SSB and LSB) were acquired using an intraoral scanner with ISB. Two different conventional techniques were also evaluated: PEEK short scan body with coping plastic cap (CPC) and pick-up coping (PUC) (n = 12). The implant impressions (CPC and PUC) were recorded using a conventional impression technique. The crown and abutment were fabricated with a milling machine and then placed on the resin model and scanned using a laboratory scanner. The scanned files were saved as STL files to serve as test datasets. The MRM and test datasets were superimposed, and the mesial, distal, and occlusal distances were calculated using a 3D inspection software and statistically analyzed using the Kruskal–Wallis H test (α = 0.05). The direct data capture group had more accurate contact points on the three surfaces, with mesial contact of 64.7 (12.8) µm followed by distal contact of 65.4 (15) µm and occlusal contact of 147 (35.8) µm in the SSB group, and mesial contact of 84.9 (22.6) µm followed by distal contact of 69.5 (19.2) µm and occlusal contact of 115.9 (27.7) µm in the LSB group (p < 0.001). The direct data capture groups are closer to the ideal proximal and occlusal contacts for single implant crowns than the indirect data capture groups. There was no difference in the accuracy between the two types of scan body (SSB and LSB).

scholarly journals Effect of assistive devices on the precision of digital impressions for implants placed in edentulous maxilla: an in vitro study

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Rena Masu ◽  
Shinpei Tanaka ◽  
Minoru Sanda ◽  
Keita Miyoshi ◽  
Kazuyoshi Baba
Keyword(s):  
Reference Model ◽  
In Vitro Study ◽  
Assistive Devices ◽  
Assistive Device ◽  
Digital Impression ◽  
Digital Impressions ◽  
Device Type ◽  
Two Factors

Abstract Purpose To examine the effect of assistive devices on the precision of digital impression for multiple implants placed in the edentulous maxilla. Methods A reference model representing an edentulous maxilla with four implants was developed. The digital impression group included three settings: Type 0, without an assistive device; Type 1, with an assistive device connecting only neighboring implants; and Type 2, with an assistive device connecting not only neighboring implants but also the two posterior implants, with perpendicular branches from this bar towards the anterior implants. Digital impressions were made five times for each type using three intraoral scanners (IOSs). For conventional method, silicone impressions and verification jigs were prepared; fabricated plaster models were scanned using a laboratory scanner/industrial 3D scanner. In analysis 1, two-way ANOVA analyzed the effect of IOSs and assistive devices on the precision of digital impressions. In analysis 2, one-way ANOVA compared the silicone impressions, the verification jigs, and the most precise group of digital impressions from analysis 1. Results In analysis 1, the IOS and assistive device type (F = 25.22, p < .0001) effects and the interaction between these two factors (F = 5.64, p = .0005) were statistically significant. In analysis 2, CON, VJ, and digital impression with Type 2 devices (most precise devices in analysis 1) were compared; better precision was obtained by digital impression with Type 2 device than by CON and VJ (F = 30.08, p < .0001). Conclusions For implants placed in an edentulous maxilla, digital impressions with assistive devices can provide better precision compared to silicone impressions and verification jigs.

scholarly journals Photoelastic analysis of stress generated by Connecticut Intrusion Arch (CIA)

2017 ◽  
Vol 22 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Alessandro Schwertner ◽  
Renato Rodrigues de Almeida ◽  
Alcides Gonini Jr ◽  
Marcio Rodrigues de Almeida
Keyword(s):  
Descriptive Analysis ◽  
Reference Value ◽  
In Vitro Study ◽  
Distal Region ◽  
Dental Arch ◽  
Apical Region ◽  
Anterior Teeth ◽  
Distal Surface ◽  
Group 2

ABSTRACT Objective: The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Methods: Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Results: Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Conclusion: Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back.

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