Search Results (72)

The integration of artificial intelligence (AI) and advanced digital workflows is revolutionising full-arch implant dentistry, particularly for geriatric patients with edentulous and atrophic arches, for whom achieving both prosthetic passivity and optimal aesthetic outcomes is critical. This narrative review evaluates current challenges in intraoral scanning accuracy—such as scan distortion, angular deviation, and cross-arch misalignment—and presents how innovations like the Medit SmartX AI-guided workflow and the Scan Ladder system can significantly enhance precision in implant position registration. These technologies mitigate stitching errors by using real-time scan body recognition and auxiliary geometric references, yielding mean RMS trueness values as low as 11–13 µm, comparable to dedicated photogrammetry systems. AI-driven prosthetic design further aligns implant-supported restorations with facial symmetry and smile aesthetics, prioritising predictable midline and occlusal plane control. Early clinical data indicate that such tools can reduce prosthetic misfits to under 20 µm and lower complication rates related to passive fit, while shortening scan times by up to 30% compared to conventional workflows. This is especially valuable for elderly individuals who may not tolerate multiple lengthy adjustments. Additionally, emerging AI applications in design automation, scan validation, and patient-specific workflow adaptation continue to evolve, supporting more efficient and personalised digital prosthodontics. In summary, AI-enhanced scanning and prosthetic workflows do not merely meet functional demands but also elevate aesthetic standards in complex full-arch rehabilitations. The synergy of AI and digital dentistry presents a transformative opportunity to consistently deliver superior precision, passivity, and facial harmony for edentulous implant patients. Full article

Background: Accuracy of optical impressions—defined by the intraoral scanner (IOS)’s trueness and precision per International Organization for Standardization (ISO) standards—is influenced by both operator- and patient-related factors. Thus, this in vitro study aimed to (1) evaluate how scanning distance affects the accuracy of three different intraoral scanners (IOSs), and (2) identify the optimal scanning distance for each scanner. Methods: A maxillary arch model was obtained using polyvinyl siloxane impression material and poured with Type IV stone (Octa-rock royal^®, Kulzer, Germany). Using three different types of IOSs—the trios 3 shape (TRIOS ^® cart, 3Shape, Copenhagen, Denmark); the Helios 500 (Eighteeth ^®, Changzhou, China); and the Heron (3Disc ^®, Herndon, VA 20170, USA)—ten scans were performed with each of the IOSs with five predetermined distances: 0 mm, 2.5 mm, 5 mm, 7.5 mm, and 10 mm. Spacers of varying heights were designed using Meshmixer version 3.5 (Autodesk, Inc., Mill Valley, CA, USA) and three-dimensional printed with the Form 2 printer (Formlabs, Somerville, MA, USA). The scanned data was processed using Geomagic Control X (Version 16.0.2.16496, 3D Systems, Wilsonville, OR, USA). Statistical analyses were performed using R Statistical Software (version 4.2.2), with significance set at α = 0.05. Results: Scanning distance significantly influenced scan accuracy for all three scanners. The 3Disc scanner (3Disc, Herndon, VA, USA) demonstrated the highest accuracy at a 7.5 mm distance, while both the Helios 500 (Eighteeth, Changzhou, China) and Trios 3 (3Shape, Copenhagen, Denmark) scanners achieved their best accuracy at a 5 mm distance, as indicated by the lowest root mean square (RMS) values (p < 0.05). Conclusions: To conclude, each IOS has an optimal scanning distance for best accuracy. Trios 3 (3Shape, Copenhagen, Denmark) outperformed the others in both trueness and precision. Future studies should examine these effects under full-arch and clinical conditions. Full article

This in vitro study aims to compare the trueness of digital impressions obtained using two intraoral scanners (IOS) and one photogrammetry device for full-arch implant-supported rehabilitations. According to the Caramês Classification I, three models were produced with Straumann implants arranged in different spatial distributions: Option A with six implants and Options B and C with four implants each. The three models were scanned using a 12-megapixel scanner to create digital master casts. For each reference model, 30 digital impressions were acquired: 10 with the 3Shape Trios 3 intraoral scanner, 10 with the Medit i500 intraoral scanner, and 10 with the PIC Dental photogrammetry device. Trueness was assessed through best-fit superimpositions between the digital master casts and the corresponding virtual models. The Shapiro–Wilk test was applied to assess the normality of the data distribution, and Levene’s test was used to evaluate the homogeneity of variances. The non-parametric Kruskal–Wallis test was employed to compare group differences, with post hoc adjustments made using the Bonferroni correction. A significance threshold of p = 0.05 was adopted for all statistical tests. Statistically significant differences were observed in the root mean square values among the three devices. The Medit i500 demonstrated the highest trueness, with a median (interquartile range) deviation of 24.45 (18.18) µm, whereas the PIC Dental exhibited the lowest trueness, with a median deviation of 49.45 (9.17) µm. Among the implant distribution, the Option C showed the best trueness, with a median deviation of 19.00 (27.83). Considering the results of this in vitro study, intraoral scanners demonstrated comparable trueness, whereas the photogrammetry-based system exhibited lower trueness values. Additionally, a smaller number of implants and reduced inter-implant distances were associated with improved trueness in digital impressions for full-arch implant rehabilitation. Full article

Background. Digital dentistry continues to evolve, offering improved accuracy, efficiency, and patient experience across various prosthodontic procedures. Many previous reviews have focused on digital applications in prosthodontics. But the use of a fully digital workflow for full-arch implant-supported prostheses in edentulous patients remains an emerging and underexplored area in the literature. Objective. This article presents a comprehensive methodological review of the digital workflow in full-arch implant-supported rehabilitation. It follows a structured literature exploration and synthesizes relevant technological processes from patient assessment to prosthetic delivery. Methods. The relevant literature was retrieved from the PubMed database on 20 June 2024, to identify the most recent and relevant studies. A total of 22 articles met the eligibility criteria and were included in the review. The majority included case and technical reports. Results. The review illustrates the integration and application of digital tools in implant dentistry, including cone-beam computed tomography (CBCT) exposure, intraoral scanning, digital smile design, virtual patients, guided surgery, and digital scanning. The key findings demonstrate multiple advantages of a fully digital workflow, such as reduced treatment time and cost, increased patient satisfaction, and improved interdisciplinary communication. Conclusions. Despite these benefits, limitations persist due to the low level of evidence, technological challenges, and the lack of standardized protocols. Further randomized controlled trials and long-term clinical evaluations are essential to validate the effectiveness and feasibility of a fully digital workflow for full-arch implant-supported rehabilitation. Full article

Background: The increasing adoption of digital workflows in implant dentistry necessitates rigorous assessment of intraoral scanning, particularly for complex full-arch rehabilitations like All-on-Four prostheses, where posterior implant angulation may impact the accuracy of optical data acquisition. Objectives: This in vitro study aimed to assess the accuracy of digital intraoral scanners in scanning All-on-Four implant models with different posterior implant angulations. Methods: Two epoxy resin All-on-Four implant models were fabricated with two posterior implant angulations (30-degree and 45-degree). Both models were digitized to obtain control datasets using a Smart Optics reference scanner (REF). Four intraoral scanners were comparatively assessed: Cerec Omnicam AC (OMN), Trios 4 (TRI), Cerec Primescan AC (PRI), and Medit i700 (MED), with nine scans per each scanner (n = 9). All STL files were exported and analyzed using Geomagic Control X with root mean square (RMS) values computed for trueness and precision assessments. Results: The comparison between IOS types in terms of trueness revealed that with 30° angulation, the MED group showed the statistically significant least deviation (p = 402). With 45° angulation, both PRI and OMN scanners showed the statistically significant highest deviation values (p = 0.047 and 0.007, respectively). MED again showed the statistically significant least deviation (p = 402). For precision evaluation in 30° angulation models, PRI and OMN scanners showed the statistically significant least deviation values (p = 402 and <0.001, respectively). While, in 45° angulation models, no statistically significant inter-scanner differences were observed. Conclusions: While MED, PRI, and OMN scanners demonstrated clinical validity for 30° angled posterior implants, only the MED system achieved sufficient accuracy for 45° tilt. These findings emphasize the critical relationship between scanner selection and extreme implant angulations in full-arch digital workflows. Full article

Background/Objectives: Digital workflows for implant-supported full-arch restorations remain challenging. This study evaluated the accuracy and precision of digital impressions using reverse scan body (RSB) prototypes and intraoral scanners (IOSs) for rehabilitating fully edentulous patients following the All-on-4 protocol. Secondary objectives included comparing accuracy between expert clinicians and beginners, as well as desktop scanners and various RSB designs. Methods: An in vitro study was conducted using a fully edentulous mandible model with four Osstem TSIII implants. A final-year dental student and an expert clinician captured digital impressions using IOSs and desktop scanners. Four groups were analyzed: (A) original scan bodies with the IOS, (B) short RSBs with the IOS, (C) RSBs with desktop scanners (short sandblasted, long sandblasted, long coated), and (D) a control group using original scan bodies with a desktop scanner. Root mean square (RMS) values measured dimensional differences, with statistical analysis performed using the Wilcoxon signed-rank test and one-way ANOVA (α = 0.05). Results: A total of 42 scans were analyzed. No significant difference was found between expert and student for original scan bodies using the IOS (p = 0.220), while RSB prototypes showed significant differences (p = 0.008). No significant accuracy differences were noted between original scan bodies and RSBs with the IOS, but IOSs outperformed desktop scanners. Among RSBs scanned with desktop scanners, no significant differences were observed between designs. Conclusions: RSB prototypes are a viable alternative to original scan bodies for fully digital workflows in All-on-4 rehabilitations, with IOSs offering superior accuracy. However, proper training is crucial for optimizing RSB accuracy. Variations in height and coating did not impact overall accuracy. Full article

Background: Dental implantology has undergone significant advancements with the integration of digital workflows, transforming the processes of planning, designing, surgical delivery, and prosthetic rehabilitation. Among these innovations, intraoral optical scanning (IOS) has emerged as a preferred method over traditional analogue impressions. This preference is due to its cost-effectiveness, efficiency, and streamlined patient-friendly use while producing clinically acceptable results in terms of trueness and precision, particularly for short-span implant prostheses. Methods: However, the clinical utility of intraoral scanning is significantly affected by the lack of reference points and difficulties in moisture and bleeding control at the time of immediate implant placement surgery in the fully edentulous arch. Current evidence supports the general consensus that the traditional analog impression technique still provides superior trueness and precision compared to IOS, specifically in full-arch implant cases. Results: The continuous quest for precision in dental implantology has led to the introduction of photogrammetry, which is now considered the most accurate technique for the digital scanning of dental implants. Photogrammetry has demonstrated superior results compared to those obtained using the analog technique. Conclusions: The aim of this case report is to provide an overview of analog techniques, digital intraoral optical scanning, and photogrammetry, setting the stage for the introduction of a novel technique involving a dedicated optical scan-transfer device (IPD^®) that can be scanned with ease using IOS, either intra- or extra-orally, due to its unique design features and digital properties. Full article

This study aims to assess and compare the shrinkage, accuracy, and accuracy stability of a novel 3D-printing model resin and eight commercially available 3D-printing model resin materials. The experimental model resin was developed by our 3D-printing proprietary resin technology. Eight commercially available 3D-printing model resins were included for comparison. The AcuVol video imaging technique was used to test volumetric shrinkage. Full-arch tooth models were printed for each model resin via digital light processing (DLP) technology. The 3D average distance between the scanned model and the designed CAD digital file was applied to determine the dimensional accuracy of the 3D-printed full-arch tooth models. One-way ANOVA and Tukey’s post hoc test (p < 0.05) were utilized to analyze the average values of volumetric shrinkage and 3D average distance (dimensional accuracy). The experimental model resin showed significantly lower volumetric shrinkage (7.28%) and significantly higher or higher accuracy and accuracy stability (11.66–13.77 µm from the initial day to four weeks) than the other commercially available model resins (7.66–11.2%, 14.03–41.14 µm from the initial day to four weeks). A strong correlation was observed between volumetric shrinkage and dimensional accuracy (Pearson correlation coefficient R = 0.7485). For clinically successful modelling applications in restorations, orthodontics, implants, and so on, the new 3D-printing model resin is a promising option. Full article

The objective of this in vitro study is to evaluate and compare the precision of digital impressions obtained using intraoral scanners and photogrammetry devices for full-arch implant-supported oral rehabilitation. Three reference models were created with various spatial distributions of Straumann implants, according to the Caramês I Classification: (i) option A with six implants; (ii) option B with four implants; and (iii) option C with four implants. Thirty digital impressions were taken for each of the reference models: ten with the Intraoral 3Shape Trios 3 scanner, ten with the Medit i500 intraoral scanner, and ten with the PIC Dental photogrammetry device. Intra-group best-fit overlaps were performed between the virtual models obtained, and accuracy was evaluated using root mean square (RMS) values. A significance level of p = 0.05 was defined. Mean values were statistically analyzed using the Kruskal–Wallis test. All scanners studied showed high precision, with RMS values similar for each implant distribution. The PIC Dental photogrammetry device demonstrated the best results for the CCI A and B distributions, with mean values of 11.28 µm and 14.44 µm, respectively. For the CCI C distribution, the 3Shape Trios 3 scanner achieved the best result, with a mean value of 5.96 µm. Among all devices, the implant distribution showing the highest RMS values was the CCI B, with mean values between 14.44 µm and 16.96 µm. The PIC Dental device was the only method that did not exhibit statistically significant differences in RMS values across the different distributions studied, indicating that its performance is unaffected by distribution variations. No statistically significant differences (p < 0.05) were observed in the RMS values among the three types of scanners. Overall, a smaller number of implants and closer distribution between them resulted in improved precision for digital impressions in full-arch implant rehabilitation. Full article

There is still no consensus on whether intraoral scanning for producing full-arch implant-supported prostheses is effective. Therefore, this systematic review aimed to analyze clinical studies that evaluated intraoral scanning versus conventional impression to obtain rehabilitation of full-arch fixed prostheses and removable. Registration was carried out in the PROSPERO database (CRD: 42020152197). Searches were performed in 11 databases. Review Manager 7.2 (2024) software was used for the quantitative analysis stage (α = 0.05). Bias analysis was conducted using the ROBINS-I and ROB scales, and the certainty of the evidence was evaluated using the GRADE scale. The initial search showed 33,975 abstracts and titles, from which, after applying the inclusion/exclusion criteria, 11 clinical studies were selected. Based on the studies collected, it was observed that there was no difference in the comparison between the digital (DG) and conventional (CG) groups for the following criteria: technical and biological complication rates and marginal bone loss (p > 0.05). The analysis of clinical execution time highlights a notable advantage of the DG over the CG at both scanned patient and implant levels (p < 0.05). Nevertheless, CG achieved fewer retakes than the DG (p < 0.05), demonstrating its reliability in execution. It is concluded that the survival rates of full-arch fixed prostheses produced using intraoral scanning are comparable to those achieved with traditional impression techniques, providing a reliable option for patients. However, further clinical studies are necessary due to the variability in clinical protocols. Full article

Background/Objectives: The technical development of implant-supported fixed dental prostheses (iFDP) initially concentrated on the computer-aided manufacturing of prosthetic restorations (CAM). Advances in information technologies have shifted the focus for optimizing digital workflows to AI-based processes for design (CAD). This pre-clinical pilot trial investigated the feasibility of the automatic design of three-unit iFDPs using CAD software (Dental Manger 2021, 3Shape; DentalCAD 3.1 Rijeka, exocad GmbH). Methods: Two clinical scenarios based on a full dentition were created virtually. Physical models were produced and digitized using two intraoral scanners applying quadrant or full-arch scans (Trios3, 3Shape, Copenhagen, Denmark; and Primescan AC, Dentsply Sirona, Bensheim, Germany). For each scenario, iFDP designs were generated automatically using two laboratory software systems (Dental Manger 2021, 3Shape; DentalCAD 3.1 Rijeka, exocad GmbH), resulting in 80 STL datasets (2 scenarios × 2 scan strategies × 2 IOS systems × 5 scan repetitions × 2 software). The files were analyzed clinically for the contact schemes and pontic area. One of the automated designs for each scenario was manually post-processed and one iFDP design for each scenario was manually created by experienced dental technicians (control). The time required for all the design processes was recorded. Results: The automatic design of iFDPs without manual adjustment did not lead to clinically acceptable restorations. The time required for the automatically generated/manually adjusted iFDPs designs was not significantly different to that for the manually designed restorations. Conclusions: Current laboratory software can not automatically generate three-unit iFDPs with clinically acceptable results in terms of the interproximal and occlusal contacts and the pontic design. The automatic iFDP design process currently requires manual adjustment, which means there is no benefit in terms of the working time compared with manually created restorations. Full article

Objectives: The aim of this study was to systematically revise the state of art of the accuracy of digital and conventional impressions in clinical full-arch scenarios. Methods: Electronic and manual searches were conducted up to December 2024. Only trials comparing the accuracy of digital versus conventional impressions were selected by two independent reviewers. Accuracy was evaluated by analysing the fit of the prostheses obtained through conventional workflows and those obtained from digital workflows using intraoral scanners. Alternatively, accuracy was assessed by comparing the standard tessellation language data acquired from intraoral scanning with those obtained from scanning the physical model. The risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. Meta-analysis was conducted to pool the mean differences from the included studies, with heterogeneity tested by Cochran’s Q test and quantified by the I² index. Results: We included 9 relevant studies from a total of 2535 identified studies. The risk of bias was evaluated as low, and the main results of all the included articles reported similar accuracy between digital and conventional impressions. Random effects meta-analysis resulted in a pooled mean difference of 152.46 (95% C.I. = 76.46–228.46, p-value < 0.001, I² = 93.48%). Conclusions: In conclusion, the results of the present systematic review reveal contradictory findings regarding the accuracy of digital impressions. However, most studies analysing the clinical performance of prostheses obtained through digital impressions suggest that their accuracy falls within clinically acceptable thresholds. Future research should report comparable outcomes and focus attention on linear deviations, comparing differences between conventional and digital impressions not in absolute terms, but relative to the distance measured. Full article

Full-arch zirconia restorations on implants have gained popularity due to zirconia’s strength and aesthetics, yet they are still associated with challenges like structural fractures, peri-implant complications, and design misfits. Advances in CAD/CAM and digital workflows offer potential improvements, but a technique that consistently addresses these issues in fixed, full-arch, implant-supported prostheses is needed. This novel technique integrates a facially and prosthetically driven treatment approach, which is divided into three phases: data acquisition, restoration design, and manufacturing/delivery. Digital tools, including intraoral scanning and photogrammetry, facilitate accurate implant positioning, while 3D design software enables functional and aesthetic validation before final milling. A dual software approach is used to reverse engineer a titanium bar from the final restoration design, ensuring a superior outcome to other protocols. The restoration incorporates a zirconia–titanium hybrid structure, optimizing strength, flexibility, and weight. The proposed workflow enhances restoration precision and predictability through a prosthetically driven treatment plan, by ensuring passivity and aligning with biological and mechanical principles to promote long-term stability. By starting with the proposed restoration design and reverse engineering the bar, while also allowing for flexibility in material and component choices, this technique accommodates both patient needs and financial considerations. This approach demonstrates potential for improving patient outcomes in full-arch implant restorations by minimizing complications associated with traditional methods. Further research is recommended to validate the technique’s efficacy and broaden its clinical applications. Full article

Objectives: The purpose of this clinical study is to compare implant full-arch intraoral scans taken immediately after implant placement with those obtained after tissue healing in patients rehabilitated with implant-supported fixed prostheses. Methods: Between September 2023 and March 2024, a total of 19 patients with compromised residual dentition (6 women; 13 men) were rehabilitated using 4-to-6 immediately loaded post-extraction implants. These implants supported fixed full-arch screw-retained prostheses either in the lower jaw (9 patients) or upper jaw (10 patients). Intraoral scans were taken immediately after implant placement (termed “immediate scan”). After a healing period of four months, the provisional prosthesis was removed, and a second intraoral scan was performed using the same scan bodies and scan pattern as the initial scan (termed “delayed scan”). The two scans were overlaid, and the discrepancies between them were measured. Results: The average discrepancy between the immediate and delayed scans was 0.1905 mm. Our statistical analysis revealed larger discrepancies for implants placed in the posterior areas, with the implant in site 1.6 (Implant 1) showing a discrepancy of 0.2326 mm, and the implant in site 2.6 (Implant 4) showing a discrepancy of 0.2124 mm (p = 0.05). No statistically significant difference was observed when comparing patients treated in the upper and lower jaws. Conclusions: Within the limitations of the study and based on this result, clinicians should be aware that an immediate post-surgical intraoral digital scan for implant-supported full-arch rehabilitations may result in a higher risk of imprecision. Furthermore, according to the results of the study, the accuracy of the digital impression on implant full-arch rehabilitations seems to be influenced by the clinician’s skills. Further studies with larger sample sizes are required to confirm our results. Full article

Introduction: This pilot two-arm, parallel group, randomized clinical trial aimed to compare the efficacy of tooth movement and patient comfort during orthodontic leveling and alignment with the BRIUS™ lingual system (BR) versus labial full fixed appliances (LFFAs). Methods: Patients in the permanent dentition with mild to moderate crowding were recruited at the University at Buffalo and randomly assigned into the BR group (seven patients) or LFFAs group (six patients). The patients’ dental arches were scanned before bonding (T1) and after 18 weeks (T2). Digital dental model superimpositions were performed to three-dimensionally evaluate tooth movement. Changes between T1 and T2 were measured in the x, y, and z planes. Little’s Irregularity Index (LII) was also assessed at T1 and T2. An electronic questionnaire was completed daily for 7 days after T1 to evaluate the patients’ comfort levels. Results: After 18 weeks, similar displacements were observed for all teeth in both groups except for the lower left second premolar (LL5) in the x-axis which showed greater displacement in the BR group (p = 0.016). Groups showed similar changes in LII. Discomfort during the first week after bonding was greater on the tongue in the BR group and on the lips and cheeks in the LFFAs group. Tongue discomfort caused by the BR lasted for around 3 days. Conclusion: The BR and LFFAs showed similar teeth displacements and therefore were equally effective at leveling and aligning teeth. LFFAs caused cheek- and lip-borne discomfort while the BR caused tongue-borne discomfort during the first week after bonding. Larger studies with longer follow-ups are needed to obtain more definitive results. Full article