The impact of surface dimensions on the accuracy of an intraoral scanner.

Impact of number of maxillary fixation landmarks on the registration accuracy of an implant scanningworkflow.

Automated detection of tooth loss using tooth numbering segmentation in 3D intraoral scans from a population-based sample with artificial intelligence.

Complete arch digital implant scans in the edentulous maxilla: Trueness and time efficiency based on scan body height, splinting, location, and scanner system.

Noncalibrated implant scan body system oriented toward the center of the arch: Accuracy of complete arch implant scans recorded using five intraoral scanners.

Alginate impressions are often distressing for preschoolers and challenging for those with gag reflexes, making intraoral scanners a preferable alternative. To assess and compare discomfort, dental anxiety, behaviour, and procedure time between intraoral scanning and alginate impressions in preschoolers. Sixty-six children aged 4-6 years were randomly allocated into two equal groups: digital impressions using an intraoral scanner (Group I) or conventional alginate impressions (Group II). Discomfort was assessed by the operator using a Visual Analogue Scale (VAS) and by children using a modified emoji-based VAS. Dental anxiety was measured using the Facial Image Scale (FIS), behaviour using Venham's Behaviour Rating Scale (VBRS), and procedure time was recorded with a digital stopwatch. The digital impression group experienced significantly lower discomfort scores (p < 0.001), more cooperative behaviour (p = 0.025), and shorter procedure time (p < 0.001) compared with the conventional impression group. No statistically significant difference in dental anxiety was observed before and after digital scanning (p = 0.257), nor before and after alginate impression taking (p = 0.065). Intraoral scanners appear to offer a more comfortable and quicker alternative for dental impressions in cooperative preschool children at their first dental visit, leading to better behavioural outcomes. ClinicalTrials.gov identifier: NCT06623851.

Complete arch implant surgical guide for accurate implant scanning without photogrammetry device: A workflow based on the calibrated intraoral scan protocol (CISP).

A systematic review and meta-analysis of the accuracy of complete arch implant scanning techniques performed extraorally: Reverse impression and extraoral photogrammetry methods. Report of the Committee on Research in Fixed Prosthodontics of the American Academy of Fixed Prosthodontics.

Accuracy of complete arch implant scans using nonsplinting techniques: A systematic review and meta-analysis. Report of the Committee on Research in Fixed Prosthodontics of the American Academy of Fixed Prosthodon.

Internal fit and marginal adaptation of digitally fabricated interim fixed dental prostheses.

The present study investigated the combined influence of four different scanning patterns and two intraoral scanning (IOS) technologies (Confocal Ultrafast Optical Sectioning vs. Active Triangulation with Structured Light) on the trueness and precision of both the intaglio and cameo surfaces of a maxillary reference denture. A maxillary complete arch reference denture was scanned using IOS technologies: Confocal Ultrafast Optical Sectioning (CUOS) and Active Triangulation with Structured Light (ATSL). Scanning was done 80 times with four strategies: APBOP (starting on the posterior intaglio surface), PABOP (beginning at the palatal aspect of the intaglio surface), BOPAP (starting on the cameo surface), and POBAP (beginning at the palatal cameo surface). Each strategy involved thorough scanning of various aspects, including occlusal surfaces, to capture the complete dentate arch. Distance-deviation values were calculated from comparisons with the STL reference model, and the data were analyzed using two-way ANOVA and Tukey's test. For the CUOS IOS technology, the POBAP scanning pattern exhibited the highest trueness (161 ± 6 μm) and precision (151 ± 7 μm), whereas the APBOP pattern showed the lowest trueness (183 ± 28 μm) and precision (171 ± 33 μm). For the ATSL IOS technology, the POBAP pattern also demonstrated the highest trueness (200 ± 32 μm) and precision (198 ± 32 μm), whereas the PABOP pattern showed the lowest trueness (241 ± 24 μm) and precision (239 ± 24 μm). The main effect of scanning technology was statistically significant (p < 0.001), with the estimated marginal mean (EMM) for CUOS being 171 μm, indicating greater trueness relative to ATSL (211 μm). A partial eta-squared value of 0.52 indicated that scanning technology explained approximately 52% of the total variation in trueness, representing a substantial effect size. CUOS consistently exhibited superior trueness across all scanning patterns compared with ATSL.

MADCrowner: Margin Aware Dental Crown design with template deformation and refinement.

Tooth3dNet: A preliminary exploration for automatic 3D morphology design of dental crowns with a deep generative network.

To present a fully digital workflow for mandibular stabilization that reproduces the conventional articulator-based process within a virtual environment, integrating patient-specific three-dimensional (3D) datasets and artificial intelligence (AI)-assisted alignment. The workflow involves registration of intraoral scans, cone-beam computed tomography (CBCT), and/or facial scans to construct a unified virtual patient. Mandibular casts are mounted in centric relation on a virtual articulator using reference best-fit alignment. A virtual face-bow transfer aligns the maxillary cast to the articulator orientation plane based on anatomical landmarks from CBCT or facial scans. Stabilization splints are digitally designed with adjustable condylar guidance and anterior ramp inclination and fabricated via liquid crystal display (LCD) 3D printing with optimized orientation and post-processing. Clinical follow-up includes repeated digital centric relation bite registrations to monitor condylar position and confirm mandibular stability. The fully digital workflow achieves mandibular stabilization while maintaining the biomechanical objectives of conventional methods. AI-assisted alignment, computer-aided design (CAD)-based splint design, and validated 3D printing parameters enhance precision, reproducibility, and clinical efficiency. This protocol provides a reproducible and clinically feasible approach to mandibular stabilization, bridging conventional occlusal principles with digital implementation, and establishing a foundation for future AI-integrated occlusion-centered therapy.

Effect of premolar extractions on occlusal contacts and chewing efficiency: A case-control study.

Accuracy of scanning using photogrammetry and reverse scan for complete arch implant-supported prostheses: An in vitro comparative study.

To investigate the impact of spatial positions of the transfer fork registration markers on the accuracy of generating a virtual dentofacial patient. An in vitro study was conducted using a mannequin head with a standard maxillary dentition model. Radiopaque gauge markers were fixed on the face and dentition of the mannequin head. CBCT was performed and the distance and angle between the dentition and facial markers were measured in the CBCT as reference values. Intraoral scanners were used to obtain 3D morphological data of the maxilla. Two types of transfer fork were designed and fabricated. The registration markers on transfer fork A were positioned in the midline area, while those on transfer fork B were located at the corners of the mouth on both sides. The transfer forks were digitised and connected to the maxillary dentition within the mannequin head, and facial scanning was performed using a facial scanner five times in each group. A virtual dentofacial patient was built through matching and integration of digital dentition, face and transfer fork data using 3D reverse engineering software (Geomagic Wrap 2021, 3D Systems, Rock Hill, SC, USA). Measurement values including feature lengths and feature angles between six facial gauge markers and three dentition gauge markers were obtained in the virtual patients. The mean trueness and precision of linear difference for virtual patients established using transfer fork A were -1.00 ± 0.11 mm and 0.27 ± 0.02 mm and the angle deviation was -1.88 ± 0.27 degrees, whereas for transfer fork B, the mean trueness and precision of linear difference were 2.66 ± 0.25 mm and 0.83 ± 0.06 mm, and the angle deviation was 3.74 ± 0.87 degrees. There is an overall significant difference in the trueness values of feature lengths (t = -13.963, P = 0.000) and angles (t = -5.985, P = 0.004) between transfer fork groups A and B, with group A showing better trueness and precision. Linear and angular errors will be introduced in the process of building up a virtual dentofacial patient using a transfer fork. The trueness and precision of the transfer fork with the matching markers at the centre of the lips are more precise than the transfer fork, with matching markers on both sides of the mouth.

To evaluate the invivo effect of varying experimental lighting conditions on the digital shade determination and scanning accuracy (trueness and precision) of two intraoral scanners (IOSs). The maxillary arches of 10 volunteers were scanned using two IOSs (Trios 4 wireless, 3Shape A/S [TR]; and Primescan, Dentsply Sirona [PR]). Scans were performed under four illuminance levels (0, 500, 1000, and 2500 lx) with scanner-specific color temperature (TR: 5500 K; PR: 4100 K). Digital shade selection was performed at the middle third of the right central incisor against visual consensus by three experts for Vita toothguide Classical (VC) and Vita toothguide 3D-Master (VM) shade guides. Scanning accuracy was assessed by superimposing IOS scans onto reference datasets obtained by digitizing conventional stone models with a laboratory scanner (InEos X5; Dentsply Sirona). Shade matching capability (accuracy and reliability) was also evaluated. Data were statistically analyzed using one-way ANOVA (α = 0.05). Ambient lighting significantly influenced digital shade matching and scanning trueness (p < 0.05). For shade matching accuracy, TR demonstrated the highest values at 1000 lx/5500 K (VC: 93.33% ± 14.05%; VM: 76.67% ± 22.50%), while PR performed best at 2500 lx/4100 K (VC: 96.67% ± 10.54%; VM: 50.00% ± 28.33%). TR produced significantly lower reliability results at the "no-light" (0 lx) condition (p < 0.05), whereas PR displayed no significant difference among groups (p > 0.05). For scanning trueness, TR exhibited the lowest deviation at 1000 lx/5500 K (104.04 ± 20.88 μm), while PR performed best at 2500 lx/4100 K (100.78 ± 19.36 μm). Ambient lighting conditions significantly affected IOS performance invivo. The optimal conditions were scanner-dependent: TR performed best under typical examination room lighting (1000 lx, 5500 K), while PR excelled under dental operatory lighting (2500 lx, 4100 K). To optimize digital impressions and esthetic shade matching, clinicians should adjust ambient lighting according to the specific requirements of the intraoral scanner being used.

This clinical trial was conducted to compare the four types of static fully guided surgical guides (bilateral tooth-supported guides, unilateral tooth-supported guides, mucosa-supported complete arch guides, and stackable bony-supported guides) in terms of accuracy. To compare all static guided protocols (bilateral tooth supported, unilateral tooth supported, full arch mucosa supported, stackable bone supported) with each other under homogenous conditions, accuracy is defined as the closeness of spatial agreement between any given implant as planned (reference) and as inserted (measurement), expressed by four spatial deviation parameters. All patients in this investigation underwent a cone beam computer tomography with standard settings. Meanwhile, digital impressions were taken by an intraoral scanner. Implant planning software was used, considering a prosthetic-driven approach. Fully guided surgeries were executed. To evaluate the four groups of fully guided surgical guides, a digital imprint was obtained immediately after surgery. All STL files were imported into CAD software, and a digital library translated scan bodies to implant fixture replicas. For trueness tests, new STL files were loaded into an inspection program. A single experienced surgeon inserted 86 implants using four different types of fully guided surgical guides. For the angular deviation, the Kruskal-Wallis test showed that there was no significant difference (P=.117). In contrast, for the coronal global and apical global deviations, as well as the vertical discrepancies, there was a statistically significant difference between the four groups (P=.022), (P=.018), (P < .001), respectively. A Dunn-Bonferroni test was used to compare the groups in pairs to identify any significant differences. Given the limitations of this study, the trueness of the four categories of fully guided surgical guides falls within an acceptable range. Nevertheless, when utilizing mucosa-supported and stackable guides, operators should consider inherent deviations and exercise heightened vigilance. 27. 04. 2025. NCT06947057.

Soft-tissue substitutes are increasingly used to avoid donor-site morbidity associated with autogenous grafting, yet direct preclinical comparisons of acellular allogenic dermal matrix (ADM) and collagen matrix (CM) remain scarce. This study investigated the early healing and remodeling profiles of ADM and CM in a canine split-mouth model. Eight male mongrel dogs (16 labial sites at the maxillary second incisors) received randomized subperiosteal tunnel grafting with ADM or CM and were euthanized at 4 or 8 weeks (n = 4 per time point). Gingival thickness and volume were quantified by 3D intraoral scans. At sacrifice, histometric thickness, rete peg counts, hematoxylin and eosin interface morphology, and immunohistochemical expression of type I collagen (Col I) and vascular endothelial growth factor (VEGF) were evaluated. Both materials produced immediate soft-tissue gains followed by partial contraction during healing while remaining above baseline. At 4 and 8 weeks, no detectable between-material differences were observed in histometric and 3D outcomes, rete peg counts, or VEGF expression. Histology showed close graft-host apposition at 4 weeks and a denser, collagen-rich interface at 8 weeks. Col I expression increased in both groups. These findings suggest similar early healing and connective tissue remodeling patterns within the limitations of this short-term canine model.