Volumetric Analysis of Peri-implant Tissue Change Over Time: Validating an Innovative 3D Method.

PURPOSE: To validate an innovative 3D volumetric method of evaluating tissue changes proposed by Lee et al in 2020 by comparing the results of this method-in which the scanned peri-implant surfaces were transformed, visualized, and analyzed as 3D objects-to the results reported by an existing method based on calculation of the mean distance between measured surfaces. The null hypothesis was that there was no statistically significant difference between the two methods. Additionally, the present study evaluated peri-implant tissue changes 5 years after single implant placement in the esthetic zone. MATERIALS AND METHODS: Both methods were applied to 11 oral implant site casts (6 maxillary central incisor sites, 5 maxillary lateral incisor sites) taken from 11 patients at crown placement and at follow-up examinations 5 years later. The methods are based on digital workflows in which the reference and 5-year casts are scanned and the resulting STL files are superimposed and analyzed for three regions of interest (mesial papilla, central area, and distal papilla). The volumetric changes reported by the Lee et al method and the mean distance method were calculated and compared using the Spearman rank correlation coefficient (P < .01) and the Wilcoxon signed-rank test (P < .05). RESULTS: The correlation between the two sets of measurements was very high (Spearman rank correlation coefficient = 0.885). The new volumetric method indicated a mean volume loss of 2.82 mm3 (SD: 5.06), while the method based on the measurement of mean distance showed a mean volume loss of 2.92 mm3 (SD: 4.43; Wilcoxon signed-rank test result: P = .77). No statistically significant difference was found. The two methods gave equivalent results, and the null hypothesis was accepted. CONCLUSIONS: The new volumetric method was validated and can be considered a trustworthy tool.

Augmented-reality-assisted intraoral scanning: A proof-of-concept study.

PURPOSE: The aims of the present study were (a) to compare the scanning time and image count to complete optical scans of a typodont between augmented-reality-assisted intraoral scanning (ARIOS) and intraoral scanning (IOS); (b) to compare the accuracy of the digital casts derived from ARIOS and IOS; (c) to compare participant-related outcomes between ARIOS and IOS. MATERIALS AND METHODS: A multi-session within-subject experiment was conducted to compare ARIOS and IOS. Thirty-one dental students participated in the study. Following a trial session, each participant obtained optical scans under ARIOS and IOS conditions. The time required to complete the scan, and the number of images taken were recorded. Participant feedback was collected using entry, exit, and NASA-Task Load Index (TLX) surveys. The accuracy of the digital casts derived from the optical scans was measured in root mean square error (RMSE). RESULTS: The present study found a 6.8% increase in preference for ARIOS from entry to exit survey. Slightly more participants favored the ARIOS setup compared to IOS; 54.8% of participants favored ARIOS, 9.7% were indifferent, and 35.5% favored IOS. NASA-TLX subscale ratings were higher for IOS in general apart from mental demand. The accuracy of the digital casts between ARIOS and IOS was comparable in RMSE. CONCLUSION: ARIOS was advantageous compared to IOS in ergonomics, improved scanner tracking, and ease of scanner orientation. However additional trials, increased field of view, and better superimposition of scanning status to the target site were improvements desired by the study participants.

Wear Resistance of Additively Manufactured Resin with Different Printing Parameters and Postpolymerization Conditions.

PURPOSE: To evaluate the wear resistance of a printed interim resin manufactured with different printing and postpolymerization parameters. MATERIALS AND METHODS: Overall, 130 rectangular resin specimens (15 × 10 × 10 mm) were 3D-printed. Among the specimens, 60 were printed with different printing orientations (0, 45, and 90 degrees) and layer thicknesses (50 and 100 µm) to create six groups to investigate the effects of the printing parameters (n = 10 per group). The remaining 70 specimens were used to evaluate the effects of postpolymerization; for this, seven groups were created as follows (n = 10 per group): nonpostpolymerized; postpolymerized for 5, 15, and 30 minutes with an ultraviolet light-emitting diode (LED) device; and postpolymerized for 5, 15, and 30 minutes with an ultraviolet light bulb device. After masticatory simulation, the wear volume loss was calculated with 3D metrology software. One-way and two-way ANOVA were used for intergroup comparisons (α = .05). RESULTS: The group printed with a build angle of 45 degrees showed lower wear volume loss than the 0- and 90-degree groups (P < .01). The wear volume loss in the ultraviolet LED group was significantly greater than that in the ultraviolet light bulb group (P = .04). No significant difference was observed in the wear volume loss of the printed resin with respect to the layer thickness and polymerization time (P > .05). However, the non-postpolymerized group showed significantly greater wear volume loss than the other groups (P < .001). CONCLUSIONS: The printed resin showed greater wear resistance when it was printed at a build angle of 45 degrees and postpolymerized with an ultraviolet light bulb device.

Mechanical stability of posterior implant-supported monolithic zirconia cantilever on titanium-base abutments. An in vitro study.

PURPOSE: Investigate survival and technical complications of two-unit posterior implant-supported cantilever made of monolithic zirconia on titanium-base abutments (Zr-TiB) vs. porcelain-fused-to-metal on castable gold abutments (PFM-GA) using two different implant connections, internal butt-joint (IBJ) and internal conical (IC). MATERIALS AND METHODS: Forty-eight implants (4.3 mm diameter) were divided into four groups (n = 12) to support 2-unit mandibular premolar cantilevers with two different materials (Zr-TiB vs. PFM-GA) and two connection types (IBJ vs. IC). Tested groups were as follows: (1) IBJ/Zr-TiB; (2) IBJ/PFM-GA; (3) IC/Zr-TiB; and (4) IC/PFM-GA. Specimens were thermomechanical aged (1,200,000 cycles, 98 N, 5-55°C) with occlusal axial load on the pontic. Catastrophic and non-catastrophic events were registered, and removal torque values measured before and after aging. Specimens surviving aging were subjected to loading until failure. Survival, total complication rates, torque loss (%), and bending moments were calculated. RESULTS: From 48 specimens, 38 survived aging. Survival rates significantly varied from 16.7% (IC/PFM-GA) to 100% (IBJ/Zr-TiB; IBJ/PFM-GA; IC/Zr-TiB) (p < .01). Internal conical connection revealed significantly higher torque loss (IC/ZrTiB - 67%) compared to internal butt-joint (IBJ/Zr-TiB - 44%; IBJ/PFM-GA - 46%) (p < .01). Bending moments were higher in internal butt-joint connections than in internal conical (p < .05). CONCLUSION AND CLINICAL IMPLICATIONS: Two-unit posterior implant-supported cantilever FDPs replacing mandibular premolars composed of monolithic zirconia on titanium-base abutments demonstrated higher mechanical stability compared to porcelain-fused-to-metal on castable gold abutments in this in vitro study. The internal conical connection combined with porcelain-fused-to-metal on gold abutments revealed a high number of failures; therefore, their clinical use may be considered cautiously for this indication.

Immediately versus early placed bone-level-tapered implants supporting all-ceramic crowns on titanium base abutments: 1-year radiographic and pink esthetic outcomes of a multicenter pilot RCT.

OBJECTIVES: Aim of this study was to assess survival rates, radiographic, and pink esthetic outcomes of a bone-level-tapered (BLT) implant following immediate or early implant placement. MATERIALS AND METHODS: Patients in need of tooth extraction and one implant in the anterior or premolar area were recruited in five centers. Patients were randomly assigned to the immediate or early placement protocol. Implants were restored with all-ceramic crowns cemented to titanium-base-abutments. Radiographic bone levels, implant stability quotient (ISQ), and pink esthetic outcomes were assessed. Data were analyzed descriptively. Level of significance was set at 0.05. Differences between groups were tested using Wilcoxon-signed-rank and Mann-Whitney-U test as nonparametric tests. RESULTS: A total of 60 patients received 60 BLT implants (Institut Straumann). At 12-months, 59 implants (98.3%) were osseointegrated. The mean distance from implant shoulder to first bone-to-implant contact was 0.15 ± 0.59 mm without significant differences between the groups. Median ISQ values increased from 75.5 to 78.5. A mean buccal recession of 0.1 ± 0.70 mm occurred with no difference between groups. The mean papilla height gain in both groups was 0.5 ± 1.47 mm mesially and 0.4 ± 1.36 mm distally. CONCLUSIONS: After 1 year, immediately and early placed BLT implants exhibit similar bone level changes, ISQ values, and pink esthetic outcomes. CLINICAL SIGNIFICANCE: The present research contributes to the knowledge on clinical outcomes of immediately and early placed BLT implants restored with buccally microveneered ceramic single crowns out of two different ceramic materials. The research shows that similar esthetic and radiographic outcomes can be reached by means of immediate implant placement compared to the conventional early placement protocol. The improvement of esthetic soft-tissue parameters over time was shown for both implant placement protocols.

Influence of sterilization on the retention forces of lithium disilicate and polymer-infiltrated ceramic-network crowns bonded to titanium base abutments: An in-vitro study.

OBJECTIVES: The aim of this study was to evaluate the effect of sterilization on the retention forces of lithium disilicate (LD) and polymer-infiltrated ceramic network (PICN) crowns bonded to titanium base (Ti-base) abutments. MATERIALS AND METHODS: Forty LD and 40 PICN crowns were milled and then bonded to 80 Ti-bases with two resin composite cements: Multilink Hybrid Abutment (mh) and Panavia V5 (pv) for a total of 8 groups (n = 10). Half of the specimens (test) underwent an autoclaving protocol (pressure 1.1 bar, 121°C, 20.5 min) and the other half not (control). Restorations were screw-retained to implants, and retention forces (N) were measured with a pull-off testing machine. The surfaces of the Ti-bases and the crowns were inspected for the analysis of the integrity of the marginal bonding interface and failure mode. Student's t-test, chi-square test, and univariate linear regression model were performed to analyze the data (α = 0.05). RESULTS: The mean pull-off retention forces ranged from 487.7 ± 73.4 N to 742.2 ± 150.3 N. Sterilized groups showed statistically significant overall higher maximum retention forces (p < .05), except for one combination (LD + mh). Sterilization led to an increased presence of marginal gaps and deformities compared to no-sterilization (p < .001), while no statistically significant relationship was found between failure mode and sterilization (p > .05). CONCLUSIONS: Sterilization may have a beneficial effect on the retention forces of LD and PICN crowns bonded to titanium base abutments, although it may negatively influence the integrity of the marginal bonding interface.

Performance of an Artificial Intelligence-Based Chatbot (ChatGPT) Answering the European Certification in Implant Dentistry Exam.

PURPOSE: To compare the performance of licensed dentists and two software versions (3.5 legacy and 4.0) of an artificial intelligence (AI)-based chatbot (ChatGPT) answering the exam for the 2022 Certification in Implant Dentistry of the European Association for Osseointegration (EAO). MATERIALS AND METHODS: The 50-question, multiple-choice exam of the EAO for the 2022 Certification in Implant Dentistry was obtained. Three groups were created based on the individual or program answering the exam: licensed dentists (D group) and two software versions of an artificial intelligence (AI)-based chatbot (ChatGPT)-3.5 legacy (ChatGPT-3.5 group) and the 4.0 version (ChatGPT-4.0 group). The EAO provided the results of the 2022 examinees (D group). For the ChatGPT groups, the 50 multiple-choice questions were introduced into both ChatGBT versions, and the answers were recorded. Pearson correlation matrix was used to analyze the linear relationship among the subgroups. The inter- and intraoperator reliability was calculated using Cronbach's alpha coefficient. One-way ANOVA and Tukey post-hoc tests were used to examine the data (α = .05). RESULTS: ChatGPT was able to pass the exam for the 2022 Certification in Implant Dentistry of the EAO. Additionally, the software version of ChatGPT impacted the score obtained. The 4.0 version not only pass the exam but also obtained a significantly higher score than the 3.5 version and licensed dentists completing the same exam. CONCLUSIONS: The AIbased chatbot tested not only passed the exam but performed better than licensed dentists.

Extended porcelain veneers in the maxillary anterior region. A retrospective study with an up to 27-year follow-up

AIM: The aim of the present retrospective study was to evaluate the long-term results, including technical and biologic outcomes, of maxillary extended porcelain veneers with an incisal edge thickness above 2 mm. MATERIALS AND METHODS: Patients treated with extended porcelain veneers performed by a single clinician at University of Geneva between 1990 and 2003 were identified and invited to an examination. Of the 37 identified patients, 10 patients with 50 veneers agreed to be examined and were included. A clinical examination was performed to assess survival rates as well as technical and biologic outcomes (modified United States Public Health Services criteria). Patient records were also reviewed to retrieve patient and reconstruction data and every complication event. Patient-reported outcome measures (PROMs) were evaluated using a visual analog scale to measure esthetic satisfaction, functional and phonetic comfort, masticatory improvement, tooth sensitivity, and acceptance of restoration replacement in case of failure. Data were descriptively analyzed, and Kaplan-Meier survival estimators were computed for survival rates and complication events. RESULTS: The survival rate of the veneers was 96% after a mean follow-up of 20.7 ± 3.7 years in function. The technical complication rate amounted to 30%, including two failures, nine repairable fractures, three cracks, and one displacement due to trauma. No cavitated caries lesions or endodontic complications were registered. PROMs were very high for esthetic satisfaction and phonetic comfort. CONCLUSIONS: Within the limitations of the present retrospective study, extended porcelain veneers appear to be a successful long-term treatment option in terms of clinical outcomes and patient satisfaction.

Implant-supported single all-ceramic crowns made from prefabricated (stock) or individualized CAD/CAM zirconia abutments: A 5 year randomized clinical trial.

AIM: The aim of this randomized, prospective, and clinical multicenter study was to compare the overall clinical performance of two restorative options over a 5-year period: individualized CAD/CAM abutments veneered with a hand-layered ceramic, and prefabricated zirconium dioxide abutments veneered with press ceramic and inserted into a single edentulous gap in the anterior maxilla. MATERIALS AND METHODS: Forty subjects were recruited from two universities: 20 from the University of XX and 20 from the University of XY. Each subject received an implant to restore a single edentulous gap in the maxillary anterior region (14-24 FDI). 20 patients were randomized into each Group. Group A received a one-piece single crown produced from a prefabricated zirconia abutment with pressed ceramic and Group B received an individualized CAD/CAM zirconia abutment with a hand-layered technique. After 5 years, the aesthetic and radiographic parameters were assessed. RESULTS: Group A had four dropouts and one failure, resulting in a 95% survival rate and 95% success rate. Group B had two dropouts and two failures which resulted in a 90% survival rate and 90% success rate. No crestal bone level changes were observed, with a mean DIB of 0.06 mm in Group A and 0.09 mm in Group B. No statistically significant differences were present at baseline, 6 months, 1 year, 3 years, or 5 years for DIB values between time points and groups. Pink aesthetic score/white aesthetic score, Peri-Implant and Crown Index, and Implant Crown Aesthetic Index values were stable over time at all five points for both groups. CONCLUSION: Both implant-supported restorative options represent a valuable treatment option for the restoration of implant crowns in the anterior maxilla. CLINICAL SIGNIFICANCE: In general, the use of ceramic abutments in the anterior zone represents a valuable treatment procedure with both standardized and CAD/CAM individualized abutments and following the recommendations from the respective manufacturer(s).

Hydrofluoric acid concentration and etching time affect differently the microstructure and surface properties of pressed lithium disilicate glass ceramics.

OBJECTIVE: To evaluate the effect of different hydrofluoric acid concentrations and etching times on the surface, chemical composition and microstructure of lithium disilicate. MATERIAL AND METHODS: Ninety specimens of pressed lithium disilicate (LDS) were obtained (IPS e.max Press, Rosetta SP and LiSi Press). The specimens of each material were divided in two groups according to the hydrofluoric acid concentration: 5% and 10% (n = 15/group), and subdivided according to the etching time: 20, 40 and 60 s (n = 5/group). Crystalline evaluations and chemical composition were performed through x-ray diffraction (XRD) and energy-dispersive x-ray spectroscopy (EDS), respectively. Microstructural analyses were performed by scanning electron microscope (SEM), surface roughness (Ra), and material thickness removal evaluation. Thickness removal and Ra data were analyzed by ANOVA and Tukey test (p < 0.05). RESULTS: XRD demonstrated characteristic peaks of lithium disilicate crystals, lithium phosphate and of a vitreous phase for all materials. EDS identified different compositions and SEM confirmed different surface responses to acid etching protocols. Material and etching time influenced Ra and material thickness removal (p < 0.05). CONCLUSION: Hydrofluoric acid concentration and etching time affect the surface characteristics of LDS differently. LiSi Press presented higher resistance to hydrofluoric acid etching compared to e.max Press and Rosetta SP. CLINICAL SIGNIFICANCE: Applying the appropriate etching protocol is pivotal to avoid excessive material removal and to prevent jeopardize the mechanical and optical properties of the material.

The Accuracy of Full-Arch Intraoral Optical Impressions (IOS): Clinical Pilot Study of the Influence of the Scan Strategy, Operator, and Intraoral Scanner.

PURPOSE: To investigate the influence of a novel scanning strategy-using two new intraoral scanner devices with different operators-on the full-arch scanning accuracy for a dentate maxilla. MATERIALS AND METHODS: Two scanning strategies, a test and a control strategy, were used to produce full-arch impressions of the dentate maxilla of a study patient. Two intraoral scanning (IOS) devices were used. Five expert operators performed a total of 40 scans. The scan time was recorded for each. A reference model was obtained from the patient's maxillary arch with an analog impression. The model was later scanned with a high-precision laboratory scanner to create a digital reference model (DRM). The scanning accuracy was analyzed with 3D-analysis software using a root mean square (RMS) calculation method, and qualitative analysis was executed using machine learning software. RESULTS: The mean RMS result for the test strategy was 82.8 ± 16 µm compared to 81.5 ± 16 µm for the control strategy. The mean RMS results were 84.7 ± 15 µm for Primescan (PS) and 79.6 ± 17 µm for 3Shape (3S). As such, the scanning strategies and IOS devices did not influence the scanning accuracy. Yet, a significant difference was found when the two strategies' scanning times were compared (P = .001), as well as the IOS devices (P = .001). The operator was found to have no influence on the scanning strategy. CONCLUSIONS: The accuracy of digital impressions is not influenced by different strategies, devices, or operators, in contrast with the scanning time, which is influenced by both strategies and devices.

A Narrative Review on Polycrystalline Ceramics for Dental Applications and Proposed Update of a Classification System.

Dental zirconias have been broadly utilized in dentistry due to their high mechanical properties and biocompatibility. Although initially introduced in dentistry as an infrastructure material, the high rate of technical complications related to veneered porcelain has led to significant efforts to improve the optical properties of dental zirconias, allowing for its monolithic indication. Modifications in the composition, processing methods/parameters, and the increase in the yttrium content and cubic phase have been presented as viable options to improve zirconias' translucency. However, concerns regarding the hydrothermal stability of partially stabilized zirconia and the trade-off observed between optical and mechanical properties resulting from the increased cubic content remain issues of concern. While the significant developments in polycrystalline ceramics have led to a wide diversity of zirconia materials with different compositions, properties, and clinical indications, the implementation of strong, esthetic, and sufficiently stable materials for long-span fixed dental prostheses has not been completely achieved. Alternatives, including advanced polycrystalline composites, functionally graded structures, and nanosized zirconia, have been proposed as promising pathways to obtain high-strength, hydrothermally stable biomaterials. Considering the evolution of zirconia ceramics in dentistry, this manuscript aims to present a critical perspective as well as an update to previous classifications of dental restorative ceramics, focusing on polycrystalline ceramics, their properties, indications, and performance.

The influence of titanium-base abutment geometry and height on mechanical stability of implant-supported single crowns.

AIM: This study aimed to investigate the influence of titanium base (ti-base) abutment macro- and micro-geometry on the mechanical stability of polymer-infiltrated ceramic network (PICN) screw-retained implant-supported single crowns (iSCs). MATERIALS AND METHODS: Twelve specimens per group were used, comprising six different implant/ti-base abutment combinations restored with PICN iSCs: Nb-T (gingival height [GH]: 1.5 mm, prosthetic height [PH]: 4.3 mm), CC (GH: 0.8 mm, PH: 4.3 mm), CC-P (GH: 0.8 mm, PH: 7 mm), Nb-V (GH: 1.5 mm, PH: 6 mm), St (GH: 1.5 mm, PH: 5.5 mm), and Th (GH: 0.5 mm, PH: 9 mm). The specimens underwent thermo-mechanical aging, and those that survived were subsequently subjected to static loading until failure. The data were analyzed using a one-way ANOVA test followed by Tukey post hoc test (α = .05). RESULTS: All specimens survived thermo-mechanical aging without complications, namely, visible cracks, debonding, or screw loosening. Th group demonstrated the highest strength values among all the groups, with significant differences compared to Nb-T (p < .05), CC (p < .001), and St (p < .001). Additionally, CC-P group exhibited significantly superior fracture strength results compared to CC (p < .05) and St (p < .05). CONCLUSION: The choice of ti-base, particularly prosthetic height, had a significant influence on fracture resistance of PICN iSCs. Nevertheless, the height or geometrical features of the ti-base did not exhibit a significant influence on the mechanical behavior of the iSC/ti-base assembly under thermomechanical loading, as all specimens withstood the aging without complication or failure.

Laser induced temperature changes on the outer surface of titanium dental implants-an in vitro study.

PURPOSE: to measure the surface temperature distribution after CO2-laser heating of titanium dental implants using different power settings, application intervals and irradiation times. MATERIALS AND METHODS: 10 tissue-level-type titanium implants (Camlog Screw-line Promote Plus 4.3mm x 11mm) were embedded (Epofix, Struers ApS, Copenhagen, Denmark) and irradiated with a carbon-dioxide-laser (Denta II, Lutronic Corporation, Fremont, USA) with a wavelength of 10.6µm and at power levels of 4watts (group 1), 6watts (group 2), 8watts (group 3) and 10watts (group 4). A continuous beam mode (setting I) and non-continuous beam modes with 5second (setting II) and 10second (setting III) pause intervals were used. For each setting, a total irradiation time of 50seconds was used and repeated 10 times. The temperature was measured using external thermocouples (Testo SE & Co. KGaA, Lenzkirch, Germany) in contact with the implant surface at implant shoulder, middle and apex. A linear regression model was used to analyse the data (p = 0.05). RESULTS: Setting I demonstrated the most rapid increase in implant surface temperature in all three test sites as well as the greatest total temperature at 50 seconds of irradiation time. The greater the pause interval (settings II and III) during the 50 seconds of irradiation, the lower the rate of temperature increase as well as the total temperature in all three test sites and with all power levels. The average temperature difference between the apex and shoulder site was significant for test setting III for all groups, but not for any groups in settings I and II. CONCLUSION: Heating the internal aspect of a dental implant with a CO2-laser produces different temperature distribution profiles depending on the laser power level and the application interval. Laser-beam irradiation leads to a temperature gradient which is greatest at the implant apex and smallest at the implant shoulder.

Influence of age, training, intraoral scanner, and software version on the scan accuracy of inexperienced operators.

PURPOSE: To evaluate the effect of operator age on the scan accuracy (trueness and precision) of inexperienced operators when compared with experienced operators, and how training, intraoral scanner (IOS), and software version affect scan accuracy. MATERIAL AND METHODS: Thirty-four operators were sorted into groups: G1 (operators <25 years old, no experience), G2 (operators >40 years old, no experience), and G3 (experienced IOS operators). They conducted partial-arch scans before and after a 4-session training with two IOSs (Trios 3 and True Definition) and two software versions. These scans were compared with the reference scans obtained from conventional impressions and a laboratory scanner (IScan D103i) to evaluate trueness (mean root mean square values) and precision (standard deviation of root mean square values) with a software program (Geomagic Control X). Kruskal-Wallis and post-hoc Dunn's tests were used to evaluate the effect of age on the scan accuracy of inexperienced groups when compared with experienced operators, while the effect of training, IOS, and software version on scan accuracy was evaluated with Wilcoxon or Mann-Whitney U tests (α = 0.05). RESULTS: Before training, G1 and G2 scans had similar accuracy (p ≥ 0.065). After training, G1 scans had higher accuracy when IOS data was pooled and had higher precision with TD (p ≤ 0.004). Training increased the scan accuracy (p < 0.001), while newer software increased the trueness of inexperienced operator scans (p = 0.015). CONCLUSIONS: Age affected the scan accuracy of inexperienced operators after training, indicating that extended training may be required for older operators. Training increased the scan accuracy, and newer software increased the trueness of inexperienced operator scans.

Influence of Implant Scanbody Material and Intraoral Scanner on the Accuracy of Complete-Arch Digital Implant Impressions.

PURPOSE: To evaluate the accuracy of complete-arch digital implant impressions using different intraoral scan body (ISB) materials and intraoral scanners (IOSs). MATERIALS AND METHODS: The mandibular dental cast of an edentulous patient with six tissue-level dental implants was used as master cast. Two types of ISBs, polyether-ether-ketone (PEEK) and plasma-coated medical titanium, were used with five IOSs: TRIOS 4 (T4), Virtuo Vivo (VV), Medit i700 (Mi700), iTero5D (i5D), and Primescan (PS). To assess accuracy, digital impressions (n=10) with each IOS and ISB were compared to two reference models obtained by digitizing the master cast with each ISB type using a desktop scanner (IScan4D LS3i) and importing the scan data into metrology software (Geomagic Control X). Root-mean-square (RMS) error was employed to evaluate overall deviation values (trueness), while precision was determined using the standard deviation (SD) of RMS values. Statistical significance was set at P < 0.05. The Kruskal-Wallis test was used, followed by the pairwise comparison method with Bonferroni correction (α=.05). RESULTS: An interaction between ISB material and IOS was found (P=0.001). Plasma-coated medical titanium ISBs demonstrated significantly higher trueness and precision compared to PEEK ISBs with T4 (P=0.001), Mi700 (P=0.001; P=0.004), and i5D (P=0.001). Conversely, VV exhibited higher trueness and precision values with PEEK ISBs (P=0.005; P=0.003). PS provided the highest trueness and precision regardless of the ISB material (P=0.912). T4 showed the lowest accuracy for PEEK ISBs, and VV for plasma-coated medical titanium ISBs. CONCLUSION: Except for PS, all IOSs showed significant differences between ISB materials. PS demonstrated the highest accuracy with both ISB materials, whereas T4 had the lowest accuracy for PEEK ISBs, and VV showed the lowest accuracy for plasma-coated medical titanium ISBs.