Academic literature on the topic 'Intraoral digitizing'

Aim. To measure the trueness and precision under repeatable conditions for different intraoral scanners (IOSs) when scanning fully edentulous arch with multiple implants. Materials and Methods. Three IOSs and one industrial scanner were used to scan one edentulous master cast containing five implant scan bodies and three spheres. The cast was scanned thirty times with each scanner device. All scans were analyzed in the inspect software, and three-dimensional locations of the implants and the interarch distance between the spheres were measured. The values were compared to measurements made with one coordinate measuring machine (true value). One-way ANOVA was used to calculate the differences between IOSs and in comparison with the true value. Results. Significant differences were found between all IOSs. For the implant measurements, Trios 3 had the lowest trueness (≤114 μm), followed by Trios 3 mono (≤63 μm) and Itero element (≤−41 μm). Trios had the lowest precision (≤135 μm), followed by Itero element (≤101 μm) and Trios 3 mono (≤100 μm). With regard to the interarch distance measurements, Trios 3 had the lowest trueness (≤68 μm), followed by Trios 3 mono (≤45 μm) and Itero element (≤40 μm). Trios 3 had the lowest precision (≤206 μm), followed by Itero element (≤124 μm) and Trios 3 mono (≤111 μm). Conclusion. The results from this in vitro study suggest that precision is low for the tested IOS devices when scanning fully edentulous arches with multiple implants.

Background: with the emergence of technological innovations in the dental industry, one emerging trend has been the intraoral digitizing of patients by using intraoral scanning systems. Compared to taking conventional impressions, the use of intraoral scanners (IOS) is suitable for capturing direct optical impressions, helping to improve diagnostic efficacy, save time, reduce patient discomfort, and simplify clinical procedures. Intraoral scanning systems appear to have a high potential for providing guidance on proper standards of care. However, one main disadvantage is breathing and saliva secretion, which causes deviations, interfering with the applicability and accuracy of the optical impression. The aim of this study was to compare the validity and accuracy of three commercially available intraoral scanners, performing an analysis exploiting a wet model. Methods: an in vitro experimental study of four permanent teeth (two molars and two premolars) on the accuracy of copings obtained by subgingival preparations was performed, using an oral wet environment model. Two hundred and forty digital impressions were produced from three digital scanners using four samples. Descriptive analysis was performed using mean, standard deviation, and median. ANOVA and F-tests were performed to assess the amount of variability between the groups. For statistical analysis a 95% significance level was chosen. Results: all differences between groups were statistically significant. Conclusions: the present data implicate a huge impact of the oral biological fluids on the accuracy of digital impression to corresponding images, implying a failure of accurate impression under wetness conditions.

Background/Aim. One of the results of many years of Cerec? 3D CAD/CAM system technological development is implementation of one intraoral and two extraoral optical scanning methods which, depending on the current indications, are applied in making fixed restorations. The aim of this study was to determine the degree of precision of optical scanning methods by the use of the Cerec?3D CAD/CAM system in the process of making ceramic inlays. Methods. The study was conducted in three experimental groups of inlays prepared using the procedure of three methods of scanning Cerec ?3D system. Ceramic inlays made by conventional methodology were the control group. The accuracy of optical scanning methods of the Cerec?3D system computer aided designcomputer aided manufacturing (CAD/CAM) was indirectly examined by measuring a marginal gap size between inlays and demarcation preparation by scanning electron microscope (SEM). Results. The results of the study showed a difference in the accuracy of the existing methods of scanning dental CAD/CAM systems. The highest level of accuracy was achieved by the extraoral optical superficial scanning technique. The value of marginal gap size inlays made with the technique of extraoral optical superficial scanning was 32.97 ? 13.17 ?. Techniques of intraoral optical superficial and extraoral point laser scanning showed a lower level of accuracy (40.29 ? 21.46 ? for inlays of intraoral optical superficial scanning and 99.67 ? 37.25 ? for inlays of extraoral point laser scanning). Conclusion. Optical scanning methods in dental CAM/CAM technologies are precise methods of digitizing the spatial models; application of extraoral optical scanning methods provides the hightest precision.

Purpose: The aim of this in vitro study was to evaluate the precision and trueness of three different scanners to scan a maxillary edentulous model using three-dimensional evaluation software. Materials and Methods: A coordinate measuring machine was used as the reference scanner. Cone beam computed tomography, computed tomography (CT), and an intraoral scanner were used to digitize an edentulous gypsum model. Data were collected and loaded into three-dimensional evaluation software. The scan outputs were superimposed, and the accuracy (trueness and precision) of the scanners were compared. One-way ANOVA was used to compare the accuracy values among all groups (trueness) and to determine differences within groups (precision). Statistical significance was assessed with an independent sample t-test (= 0.05) for each group. Results: The mean precision values ranged from 3.5 to –0.2 m. Analysis of the superimposed scans onto the reference scan for each group revealed no significant differences in trueness and precision (p > 0.05) among all groups. Further, binary comparisons of the datasets of each group revealed no significant differences (p > 0.05) in terms of precision values, except in the CT group wherein significant differences (p ≤ 0.05) were observed for most models. Conclusions: No significant differences were observed in terms of accuracy (precision and trueness) among the three scanners. All scanners were effective in scanning the edentulous gypsum model.

Objectives. To analyze the location and intensity of occlusal contact points using three types of articulators: non adjustable, semiadjustable and digital with aiming at improving the diagnostic and treatment options in dental medicine. Material and method. For analyzing the distribution of contact points, the casts of a patient were mounted in the non adjustable and semiadjustable articulator. Intraoral scanning was performed using an intraoral scanner (Trios 3Shape) and reviewed in a virtual articulator. Occlusion obtained by the three methods was compared to the clinical situation. Results. Contact points in maximum intercuspation, propulsion and lateral movements were analyzed. The points obtained by using the non adjustable articulator have been less intense and more unprecise. By digitizing the contact points, the image becomes more accurate and sharp. Discussion. The semiadjustable articulator reproduces the contact points which are consistent with the clinical situation. Major differences occur when using the non adjustable articulator, which has a limited capacity of reproducing the clinical movements, therefore the marks are non consistent with the real clinical situation. The digital articulator seems promising in terms of eccentric movements. Conclusions. However performing an articulator may be, the clinical maximum intercuspation will never be fittingly reproduced, due to the fact that articulators are rigid systems, whereas the oral cavity has an elasticity, resulting from the mandible, teeth and periodontal ligaments. Virtual articulators need to be further developed for more accurate results.

For digital impression-making of two-piece oral implants, scan bodies are used to transfer the exact intraoral implant position to the dental laboratory. In this in vitro investigation, the accuracy of digitizing a one-piece ceramic oral implant without a scan body (OC) was compared to that of a standard two-piece titanium implant with a scan body (TT) and a preparation of a natural single tooth (ST). Furthermore, incomplete scans of OC simulating clinical compromising situations (OC1–4) were redesigned using a virtual reconstruction tool (RT) and superimposed to OC. OC and TT oral implants and one ST were inserted into a mandible typodont model and digitized (N = 13) using two different intraoral scanners. The resulting virtual datasets were superimposed onto a three-dimensional (3D) laser scanner-based reference. Test and reference groups were aligned using an inspection software according to a best-fit algorithm, and circumferential as well as marginal discrepancies were measured. For the statistical evaluation, multivariate analyses of variance with post-hoc Tukey tests and students t-tests to compare both scanners were performed. A total of 182 datasets were analyzed. For circumferential deviations, no significant differences were found between ST, TT, and OC (p > 0.964), but increased deviations for OC1–4 (p < 0.001) were observed. The measurements of the marginal deviations revealed that ST had the smallest deviations, and that there were no significant differences between TT, OC, and OC1–4 (p > 0.979). Except for marginal deviation of OC (p < 0.001), the outcome was not affected by the scanner. Within the limitations of this study, digitization of OC is as accurate as that of TT, but less than that of ST. In the case of known geometries, post-processing of compromised scans with a virtual reconstruction results in accurate data.

Introduction: In lingual orthodontics technique the brackets are positioned on the teeth lingual surface, and for this reason it is known as a difficult technique due to the complexity of brackets positioning. During the evolution of this technique many forms of lingual appliance assembly were developed. The most used technique recommended to make an orthodontic set-up model and later to transfer the appliance to the patient’s mouth using trays or jigs in order to perform the bonding itself. Subsequently, another and more simplified lingual appliance form emerged, in which the bonding would be performed directly, that is, on the lingual surface of the enamel, but it required greater skill from the professional. Also, it could be done on the cast model of malocclusion, without making the set-up model. Objectives: To facilitate the technique using technological resources with as a scanner and a software replacing some analogical steps in the assembly of the lingual device. Material and Method: Intraoral digitizing is performed by a scanner where the models are obtained in STL files, that inserted in the software together with the STL files of the lingual brackets will be positioned on the virtual surface of the digital models. A virtual transfer tray will be made of resin in a 3D printer where the metal brackets will be inserted for the actual bonding. Conclusion: The assembly of the simplified lingual device can be performed with excellence by digital means in almost all steps.

Durch den Einsatz von CAD/CAM-Technologien sollen potenzielle Fehlerquellen der handwerklich-manuellen Herstellung zahnmedizinischprothetischer Restaurationen eliminiert werden. Grundlage für die Fertigung einer prothetischen Restauration mittels CAD/CAM ist eine möglichst genaue Digitalisierung der klinischen Situation. In dieser Studie wurde die Genauigkeit der digitalen Erfassung von Zähnen unter experimentellen sowie unter klinischen Bedingungen mit dem CEREC-3D® System (intraoral) im Vergleich zu konventioneller Abformung und Modellerstellung mit anschließender extraoraler Digitalisierung (Digiscan) untersucht. Von einem Schulungsmodell wurde mit einer Doppelmischabformung ein Modell mit präpariertem Zahn 16 erzeugt und extraoral digitalisiert. Dieses Modell wurde simuliert intraoral sowie nach erneuter Abformung und Modellherstellung extraoral digitalisiert. Im Anschluss daran erfolgte die Zuordnung der einzelnen Datensätze auf das Referenz-CAD-Modell und die dreidimensionale Differenzberechnung. Die durch die Ethik-Kommission genehmigte klinische Studie umfasste zehn Probanden. Bei diesen zehn Probanden erfolgte eine konventionelle und optische Abformung des Oberkiefers. Aus der konventionellen Abformung entstand ein Modell, welches extraoral-optisch digitalisiert wurde. Diesen Daten wurde die optische Abformung zugeordnet. Die dreidimensionale Auswertung erfolgte analog der in-vitro Studie. Die Auswertung der in-vitro Daten lieferte mittlere dreidimensionale Abweichungen von ±17-35μm bei der Betrachtung vom präparierten Zahn 16 und seinen Nachbarzähnen. Betrachtete man nur den präparierten Zahn 16, zeigten sich mittlere Abweichungen um ±17μm. Im Vergleich dazu lag die berechnete mittlere Differenz bei der intraoralen Digitalisierung eines Quadranten mit ±26-81μm erheblich darüber. Im Registrierzentrum konnte die geringste Abweichung gefunden werden. Der konventionelle Verfahrensweg (Abformung – Modellherstellung – extraorale Digitalisierung) hingegen liefert eine Genauigkeit von ±9-19μm. Anhand der gewonnenen Ergebnisse kann man sagen, dass die CEREC-3D®Kamera für die Erfassung von Einzelzahnrestaurationen sowie gegebenenfalls kleinerer mehrspanniger Restaurationen geeignet ist. Größere Restaurationen hingegen übersteigen den Indikationsbereich des Systems und sollten extraoral über den Umweg einer Abformung digitalisiert werden. Klinische Parameter beeinflussen die Genauigkeit der intraoralen Digitalisierung in einem akzeptablen Maß. Dies wird anhand des Vergleiches der in-vitro mit den in-vivo Daten ersichtlich. Dabei ist die Puderschicht von durchschnittlich 28,6μm (51) bei der intraoralen Digitalisierung zu berücksichtigen
Using CAD/CAM-technology in dentistry is supposed to reduce or eliminate potential sources of error resulting from the manual craftsmanship needed when making dental restorative restorations. For any CAD/CAM-made restoration, a digitalization as precise as possible is basic. In this study, the precision of the digital measurement of teeth was examined in-vitro and invivo. The intraoral CEREC-3D® system was compared with conventional impression taking and model making and subsequent digitalization (Digiscan). A one-stage putty-and-wash impression was taken from a training model. The first upper molar in this model was prepared for a full crown. The resulting gypsum model was extraorally digitized. This master model was digitized with simulated intraoral digitizing and, after taking again an impression and making a gypsum model, with extraoral digitizing. The data was then aligned to the reference CAD-model, and the threedimensional differences were calculated. The clinical trial included ten probands and was approved by the responsible ethical committee. From each proband, a conventional impression as well as an intraoral digitizing was made from the upper jaw. The gypsum model resulting from the impression was digitized extraorally, and the data was aligned to the data-sets of the intraoral digitizing. The threedimensional differences were calculated analogous to the in-vitro analysis. The threedimensional analysis showed mean differences between ±17 and 35 microns for the prepared tooth 16 and its neighboring teeth. Looking at tooth 16 alone, the mean differences were around ±17 microns. Compared to these values, the mean differences calculated for intraoral digitizing of a whole quadrant were considerably higher (±26-81 microns). The smallest mean deviations were found at the center of alignment. The conventional method (impression taking - model making - extraoral digitizing) showed a significantly higher precision (±9-19 microns). The results show that the CEREC-3D®camera is suitable for single tooth and short-span restorations. However, the indication is not given for long-span restorations using the intraoral system. Such restorations should always be made after conventional impression taking, model making and subsequent extraoral digitizing. The precision of the intraoral digitizing is influenced by clinical parameters in an acceptable way as shown by the comparison of invitro and in-vivo data. The powder-layer of average 28.6 microns (51) has to be taken into consideration, when using intraoral digitizing

Durch den Einsatz von CAD/CAM-Technologien sollen potenzielle Fehlerquellen der handwerklich-manuellen Herstellung zahnmedizinischprothetischer Restaurationen eliminiert werden. Grundlage für die Fertigung einer prothetischen Restauration mittels CAD/CAM ist eine möglichst genaue Digitalisierung der klinischen Situation. In dieser Studie wurde die Genauigkeit der digitalen Erfassung von Zähnen unter experimentellen sowie unter klinischen Bedingungen mit dem CEREC-3D® System (intraoral) im Vergleich zu konventioneller Abformung und Modellerstellung mit anschließender extraoraler Digitalisierung (Digiscan) untersucht. Von einem Schulungsmodell wurde mit einer Doppelmischabformung ein Modell mit präpariertem Zahn 16 erzeugt und extraoral digitalisiert. Dieses Modell wurde simuliert intraoral sowie nach erneuter Abformung und Modellherstellung extraoral digitalisiert. Im Anschluss daran erfolgte die Zuordnung der einzelnen Datensätze auf das Referenz-CAD-Modell und die dreidimensionale Differenzberechnung. Die durch die Ethik-Kommission genehmigte klinische Studie umfasste zehn Probanden. Bei diesen zehn Probanden erfolgte eine konventionelle und optische Abformung des Oberkiefers. Aus der konventionellen Abformung entstand ein Modell, welches extraoral-optisch digitalisiert wurde. Diesen Daten wurde die optische Abformung zugeordnet. Die dreidimensionale Auswertung erfolgte analog der in-vitro Studie. Die Auswertung der in-vitro Daten lieferte mittlere dreidimensionale Abweichungen von ±17-35μm bei der Betrachtung vom präparierten Zahn 16 und seinen Nachbarzähnen. Betrachtete man nur den präparierten Zahn 16, zeigten sich mittlere Abweichungen um ±17μm. Im Vergleich dazu lag die berechnete mittlere Differenz bei der intraoralen Digitalisierung eines Quadranten mit ±26-81μm erheblich darüber. Im Registrierzentrum konnte die geringste Abweichung gefunden werden. Der konventionelle Verfahrensweg (Abformung – Modellherstellung – extraorale Digitalisierung) hingegen liefert eine Genauigkeit von ±9-19μm. Anhand der gewonnenen Ergebnisse kann man sagen, dass die CEREC-3D®Kamera für die Erfassung von Einzelzahnrestaurationen sowie gegebenenfalls kleinerer mehrspanniger Restaurationen geeignet ist. Größere Restaurationen hingegen übersteigen den Indikationsbereich des Systems und sollten extraoral über den Umweg einer Abformung digitalisiert werden. Klinische Parameter beeinflussen die Genauigkeit der intraoralen Digitalisierung in einem akzeptablen Maß. Dies wird anhand des Vergleiches der in-vitro mit den in-vivo Daten ersichtlich. Dabei ist die Puderschicht von durchschnittlich 28,6μm (51) bei der intraoralen Digitalisierung zu berücksichtigen.
Using CAD/CAM-technology in dentistry is supposed to reduce or eliminate potential sources of error resulting from the manual craftsmanship needed when making dental restorative restorations. For any CAD/CAM-made restoration, a digitalization as precise as possible is basic. In this study, the precision of the digital measurement of teeth was examined in-vitro and invivo. The intraoral CEREC-3D® system was compared with conventional impression taking and model making and subsequent digitalization (Digiscan). A one-stage putty-and-wash impression was taken from a training model. The first upper molar in this model was prepared for a full crown. The resulting gypsum model was extraorally digitized. This master model was digitized with simulated intraoral digitizing and, after taking again an impression and making a gypsum model, with extraoral digitizing. The data was then aligned to the reference CAD-model, and the threedimensional differences were calculated. The clinical trial included ten probands and was approved by the responsible ethical committee. From each proband, a conventional impression as well as an intraoral digitizing was made from the upper jaw. The gypsum model resulting from the impression was digitized extraorally, and the data was aligned to the data-sets of the intraoral digitizing. The threedimensional differences were calculated analogous to the in-vitro analysis. The threedimensional analysis showed mean differences between ±17 and 35 microns for the prepared tooth 16 and its neighboring teeth. Looking at tooth 16 alone, the mean differences were around ±17 microns. Compared to these values, the mean differences calculated for intraoral digitizing of a whole quadrant were considerably higher (±26-81 microns). The smallest mean deviations were found at the center of alignment. The conventional method (impression taking - model making - extraoral digitizing) showed a significantly higher precision (±9-19 microns). The results show that the CEREC-3D®camera is suitable for single tooth and short-span restorations. However, the indication is not given for long-span restorations using the intraoral system. Such restorations should always be made after conventional impression taking, model making and subsequent extraoral digitizing. The precision of the intraoral digitizing is influenced by clinical parameters in an acceptable way as shown by the comparison of invitro and in-vivo data. The powder-layer of average 28.6 microns (51) has to be taken into consideration, when using intraoral digitizing.