Application of holography and augmented reality based technology to visualize the internal structure of the dental root - a proof of concept

Taxonomic discordance of immersive realities in dentistry: A systematic scoping review

OBJECTIVES

This review aimed to map taxonomy frameworks, descriptions, and applications of immersive technologies in the dental literature.

DATA

The Preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) guidelines was followed, and the protocol was registered at open science framework platform (https://doi.org/10.17605/OSF.IO/H6N8M).

SOURCES

Systematic search was conducted in MEDLINE (via PubMed), Scopus, and Cochrane Library databases, and complemented by manual search.

STUDY SELECTION

A total of 84 articles were included, with 81 % between 2019 and 2023. Most studies were experimental (62 %), including education (25 %), protocol feasibility (20 %), in vitro (11 %), and cadaver (6 %). Other study types included clinical report/technique article (24 %), clinical study (9 %), technical note/tip to reader (4 %), and randomized controlled trial (1 %). Three-quarters of the included studies were published in oral and maxillofacial surgery (38 %), dental education (26 %), and implant (12 %) disciplines. Methods of display included head mounted display device (HMD) (55 %), see through screen (32 %), 2D screen display (11 %), and projector display (2 %). Descriptions of immersive realities were fragmented and inconsistent with lack of clear taxonomy framework for the umbrella and the subset terms including virtual reality (VR), augmented reality (AR), mixed reality (MR), augmented virtuality (AV), extended reality, and X reality.

CONCLUSIONS

Immersive reality applications in dentistry are gaining popularity with a notable surge in the number of publications in the last 5 years. Ambiguities are apparent in the descriptions of immersive realities. A taxonomy framework based on method of display (full or partial) and reality class (VR, AR, or MR) is proposed.

CLINICAL SIGNIFICANCE

Understanding different reality classes can be perplexing due to their blurred boundaries and conceptual overlapping. Immersive technologies offer novel educational and clinical applications. This domain is fast developing. With the current fragmented and inconsistent terminologies, a comprehensive taxonomy framework is necessary.

Assessment of pulmonary vascular anatomy: comparing augmented reality by holograms versus standard CT images/reconstructions using surgical findings as reference standard

BACKGROUND

We compared computed tomography (CT) images and holograms (HG) to assess the number of arteries of the lung lobes undergoing lobectomy and assessed easiness in interpretation by radiologists and thoracic surgeons with both techniques.

METHODS

Patients scheduled for lobectomy for lung cancer were prospectively included and underwent CT for staging. A patient-specific three-dimensional model was generated and visualized in an augmented reality setting. One radiologist and one thoracic surgeon evaluated CT images and holograms to count lobar arteries, having as reference standard the number of arteries recorded at surgery. The easiness of vessel identification was graded according to a Likert scale. Wilcoxon signed-rank test and κ statistics were used.

RESULTS

Fifty-two patients were prospectively included. The two doctors detected the same number of arteries in 44/52 images (85%) and in 51/52 holograms (98%). The mean difference between the number of artery branches detected by surgery and CT images was 0.31 ± 0.98, whereas it was 0.09 ± 0.37 between surgery and HGs (p = 0.433). In particular, the mean difference in the number of arteries detected in the upper lobes was 0.67 ± 1.08 between surgery and CT images and 0.17 ± 0.46 between surgery and holograms (p = 0.029). Both radiologist and surgeon showed a higher agreement for holograms (κ = 0.99) than for CT (κ = 0.81) and found holograms easier to evaluate than CTs (p < 0.001).

CONCLUSIONS

Augmented reality by holograms is an effective tool for preoperative vascular anatomy assessment of lungs, especially when evaluating the upper lobes, more prone to anatomical variations.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04227444 RELEVANCE STATEMENT: Preoperative evaluation of the lung lobe arteries through augmented reality may help the thoracic surgeons to carefully plan a lobectomy, thus contributing to optimize patients' outcomes.

KEY POINTS

• Preoperative assessment of the lung arteries may help surgical planning. • Lung artery detection by augmented reality was more accurate than that by CT images, particularly for the upper lobes. • The assessment of the lung arterial vessels was easier by using holograms than CT images.

Immersive virtual reality and augmented reality in anatomy education: A systematic review and meta-analysis

The purpose of this review was to (1) analyze the effectiveness of immersive virtual reality (iVR) and augmented reality (AR) as teaching/learning resources (collectively called XR-technologies) for gaining anatomy knowledge compared to traditional approaches and (2) gauge students' perceptions of the usefulness of these technologies as learning tools. This meta-analysis, previously registered in PROSPERO (CRD42023423017), followed PRISMA guidelines. A systematic bibliographical search, without time parameters, was conducted through four databases until June 2023. A meta-analytic approach investigated knowledge gains and XR's usefulness for learning. Pooled effect sizes were estimated using Cohen's standardized mean difference (SMD) and 95% confidence intervals (95% CI). A single-group proportional meta-analysis was conducted to quantify the percentage of students who considered XR devices useful for their learning. Twenty-seven experimental studies, reporting data from 2199 health sciences students, were included for analysis. XR-technologies yielded higher knowledge gains than traditional approaches (SMD = 0.40; 95% CI = 0.22 to 0.60), especially when used as supplemental/complementary learning resources (SMD = 0.52; 95% CI = 0.40 to 0.63). Specifically, knowledge performance using XR devices outperformed textbooks and atlases (SMD = 0.32; 95% CI = 0.10 to 0.54) and didactic lectures (SMD = 1.00; 95% CI = 0.57 to 1.42), especially among undergraduate students (SMD = 0.41; 95% CI = 0.20 to 0.62). XR devices were perceived to be more useful for learning than traditional approaches (SMD = 0.54; 95% CI = 0.04 to 1), and 80% of all students who used XR devices reported these devices as useful for learning anatomy. Learners using XR technologies demonstrated increased anatomy knowledge gains and considered these technologies useful for learning anatomy.

Blended Learning with Video Demonstrations Enhances Dental Students' Achievements in Tooth Carving

Background

Learning fine motor skill is central to preclinical dental education. Dental students are introduced to anatomical tooth carving to facilitate the development of their fine motor skill and manual dexterity. Various carving technique exists, such as wax build-up, and geometric (block carving technique). Since substantial laboratory Time and instructors' effort are required to teach students the desired techniques, blended learning approach via pre-recorded demonstration may improve the teaching and learning efficiency of anatomical tooth carving. For years, we used the Geometric method to teach preclinical dental students to carve down tooth sculptures after performing live demonstrations for them. Multiple practical laboratory demonstrations are necessary to deepen the student's comprehensive understanding of dental anatomical features and teach them correct instrumentation; this is time-consuming and challenging due to limited laboratory hours and limited view field. Accordingly, in 2016 the teaching staff created videos for tooth drawing, carving, and identification, and uploaded them to the students' university platform. Years later, we decided to perform this retrospective study.

Objective

To assess the enhancement in students' tooth carving skills after implementing blended learning with video demonstrations.

Methods

The student's total grades were used for comparative purposes. The students' total grades between 2010 and 2019 were collected and categorized into two groups: Group 1 (n=858), which learned tooth carving by the Geometric method after live demonstrations, and Group 2 (972), which benefited from blended learning with video demonstrations in learning. The two groups' mean, median, mode, Percentile 75, and Percentile 90 were compared.

Results

Group 2 showed higher grades than group 1, and the differences between the two groups' mean and median were statistically significant p<0.001. Moreover, the mode, P75 and P90 favored group 2.

Conclusion

Results show that blended learning with video demonstrations enhanced the achievements of dental students in tooth carving.

A mobile augmented reality-integrated oral health education for community dwelling older adults: A pilot study

Background/purpose

Providing oral healthcare education can be an optimal strategy for imparting knowledge and developing self-care skills for older adults to enhance their oral health conditions. However, traditional passive lecture-based education programs have several limitations. Integrating mobile augmented reality (MAR) into oral health education can potentially enhance the effectiveness of the education by mitigating those limitations. The objectives of this study are to develop and evaluate the effectiveness of MAR-integrated oral health education. The objectives of this study were to develop and evaluate the effectiveness of MAR-integrated oral health education.

Materials and methods

Twenty-four older adults from community dwellings participated in this study. The participants received MAR-integrated oral health education once at activity centers. Self-report questionnaires were utilized to assess oral healthcare-related knowledge and self-efficacy, and the usability score of the MAR system. The assessment was conducted before and after the educational program. Data were statistically analyzed using descriptive statistics and paired-t test.

Results

The mean scores of oral healthcare-related knowledge and self-efficacy showed a significant increase after the educational program, with P-values of <0.001 and 0.002, respectively. A majority of the participants exhibited a lack of knowledge and self-efficacy regarding the proper selection of toothpaste and interdental brushes. However, there was an improvement after the intervention. The usability score of the system was lower than the average level.

Conclusion

MAR-integrated oral health education effectively increases oral health-related knowledge and self-efficacy among community dwelling older adults. Still, the usability of the MAR system needs to be improved. Further investigation of long-term effects and clinical outcomes, and the inclusion of comparative groups are recommended for the future study.

Augmented Reality-Guided Apicoectomy Based on Maxillofacial CBCT Scans

Implementation of augmented reality (AR) image guidance systems using preoperative cone beam computed tomography (CBCT) scans in apicoectomies promises to help surgeons overcome iatrogenic complications associated with this procedure. This study aims to evaluate the intraoperative feasibility and usability of HoloLens 2, an established AR image guidance device, in the context of apicoectomies. Three experienced surgeons carried out four AR-guided apicoectomies each on human cadaver head specimens. Preparation and operating times of each procedure, as well as the subjective usability of HoloLens for AR image guidance in apicoectomies using the System Usability Scale (SUS), were measured. In total, twelve AR-guided apicoectomies on six human cadaver head specimens were performed (n = 12). The average preparation time amounted to 162 (±34) s. The surgical procedure itself took on average 9 (±2) min. There was no statistically significant difference between the three surgeons. Quantification of the usability of HoloLens revealed a mean SUS score of 80.4 (±6.8), indicating an "excellent" usability level. In conclusion, this study implies the suitability, practicality, and simplicity of AR image guidance systems such as the HoloLens in apicoectomies and advocates their routine implementation.

Evaluating augmented reality e-typodont to improve a patient's dental implant health literacy

STATEMENT OF PROBLEM

Information regarding dental implants can be difficult to understand for participants. Improving patients' dental implant health literacy remains a challenging process.

PURPOSE

The purpose of this clinical study was to develop and evaluate patients' understanding of the implant treatment procedure, components, and sequences using traditional typodont and augmented reality (AR) applications (e-typodont), with the goal of improving their oral health literacy.

MATERIAL AND METHODS

Participants who had sought dental implant treatment at the group practice and implant clinic at the University of Illinois Chicago (UIC) College of Dentistry were invited to enroll in this study. Participants were asked to fill out the first questionnaire (Q1) assessing their understanding of implant treatment procedures, components, and sequences. The participants were randomly exposed to 1 of the 2 modes of delivering education, typodont or AR e-typodont. The participants were asked to complete the additional 2 questionnaires (Q2 and Q3), and the posttest questionnaire (Q1) to re-evaluate their understanding of the implant treatment procedure, components, and sequences. All data were entered and coded into a spreadsheet. Descriptive (mean) and statistical (Wilcoxon Signed Ranks and Mann-Whitney U test) analyses were used (α=.05).

RESULTS

Both interventions significantly increased participants' understanding of implant treatments (typodont: P=.004; e-typodont: P<.001), implant components (typodont: P=.003; e-typodont: P<.001), and implant treatment sequences (typodont: P=.001; e-typodont: P<.001). The e-typodont group significantly improved participants' understanding of implant treatments (P=.006), implant components (P=.023), and implant treatment sequences (P=.008) compared with the typodont group. Participants perceived the e-typodont mode of delivery to be significantly more interesting (P=.002), interactive (P=.008), educational (P=.002), user-friendly (P=.016), and "Wow" (P=.002) compared with the traditional typodont mode of delivery.

CONCLUSIONS

Both interventions improved participants' understanding of implant treatment procedures, components, and sequences. The e-typodont showed better improvement in participants' understanding of dental implants compared with the traditional typodont.

Microsoft HoloLens 2 in Medical and Healthcare Context: State of the Art and Future Prospects

In the world reference context, although virtual reality, augmented reality and mixed reality have been emerging methodologies for several years, only today technological and scientific advances have made them suitable to revolutionize clinical care and medical contexts through the provision of enhanced functionalities and improved health services. This systematic review provides the state-of-the-art applications of the Microsoft^® HoloLens 2 in a medical and healthcare context. Focusing on the potential that this technology has in providing digitally supported clinical care, also but not only in relation to the COVID-19 pandemic, studies that proved the applicability and feasibility of HoloLens 2 in a medical and healthcare scenario were considered. The review presents a thorough examination of the different studies conducted since 2019, focusing on HoloLens 2 medical sub-field applications, device functionalities provided to users, software/platform/framework used, as well as the study validation. The results provided in this paper could highlight the potential and limitations of the HoloLens 2-based innovative solutions and bring focus to emerging research topics, such as telemedicine, remote control and motor rehabilitation.

Case Report: Modulation of Effective Connectivity in Brain Networks after Prosthodontic Tooth Loss Repair

INTRODUCTION. Recent neuroimaging studies suggest that dental loss replacements induce changes in neuroplasticity as well as in correlated connectivity between brain networks. However, as the typical temporal delay in detecting brain activity by neuroimaging cannot account for the influence one neural system exerts over another in a context of real activation (“effective” connectivity), it seems of interest to approach this dynamic aspect of brain networking in the time frame of milliseconds by exploiting electroencephalographic (EEG) data. MATERIAL AND METHODS. The present study describes one subject who received a new prosthodontic provisional implant in substitution for previous dental repairs. Two EEG sessions led with a portable device were recorded before and after positioning the new dental implant. By following MATLAB-EEGLAB processing supported by the plugins FIELDTRIP and SIFT, the independent component analysis (ICA) derived from EEG raw signals was rendered as current density fields and interpolated with the dipoles generated by each electrode for a dynamic study of the effective connectivity. One more recording session was undertaken six months after the placement of the final implant. RESULTS. Compared to the baseline, the new prosthodontic implant induced a novel modulation of the neuroplasticity in sensory-motor areas which was maintained following the definitive implant after six months, as revealed by changes in the effective connectivity from the basal strong enslavement of a single brain area over the others, to an equilibrate inter-related connectivity evenly distributed along the frontotemporal regions of both hemispheres. CONCLUSIONS. The rapid shift of the effective connectivity after positioning the new prosthodontic implant and its substantial stability after six months suggest the possibility that synaptic modifications, induced by novel sensory motor conditions, modulate the neuroplasticity and reshape the final dynamic frame of the interarea connectivity. Moreover, given the viability of the EEG practice, this approach could be of some interest in assessing the association between oral pathophysiology and neuronal networking.

Atypical Radicular Anatomy in Permanent Human Teeth: A Systematic Review

The aim of the present study is to classify and quantify the anatomical variations of teeth in terms of form and number of root canals reported in human teeth employing the classification systems proposed previously. An electronic (PubMed) and manual search were performed to identify case reports noting any of the anatomical variations. Each alteration was studied independently. The electronic search was performed using the following keywords: anatomical aberration, root canal, permanent Dentition, case report, c-shaped canal, dens invaginatus, palato-radicular groove, palato-radicular groove, palato-gingival groove, radix entomolaris, dental fusion, dental gemination, taurodontism, dilaceration. The initial search revealed 1497 papers, of which 938 were excluded after analyzing the titles and abstracts. Therefore, 559 potential papers were considered. Of those, 140 articles did not meet the inclusion criteria. For the final revision, 419 papers were considered. We found that the mandibular first premolar had the highest prevalence of C-shaped canals. Dens invaginatus was more frequently found in the mandibular lateral incisor. Taurodontism was more prevalent in the maxillary first molar and in the mandibular first molar. Dilaceration was not clearly associated with a particular tooth. The classifications systems used in this review allowed for the better understanding and analysis of the many anatomical variations present in teeth. The variations in shape most found were dens invaginatus and radix entomolaris. The most frequently reported anatomical variation was in the number of canals.