Performance and perception of dental students using three intraoral CAD/CAM scanners for full-arch scanning

Implementation of a Full Digital Workflow by 3D Printing Intraoral Splints Used in Dental Education: An Exploratory Observational Study with Respect to Students' Experiences

Fully digital workflows gained acceptance in dental practice and thereby are of interest for undergraduate education. An exploratory clinical observation was designed to track the implementation of such a workflow with novice digital users in order to describe its feasibility, time investment, and pitfalls.

METHODS

Students were invited to provide feedback for their experiences with a training module that consisted of the following: intraoral scanning, computer-aided design (CAD), manual finishing, and insertion of a 3D-printed bite splint for the lower jaw.

RESULTS

A total of 82 fourth-year students participated in the module. The average time required to perform an intraoral scan was 17 m 5 s, and all students were able to design a splint with an average time of 2 h 38 m. Students who indicated prior experience with CAD seem to outperform inexperienced students in both CAD task completion and intraoral scanning. The initial fit was reported as clinically acceptable by 68.5% of the participants, while 79% rated the workflow as very good to satisfactory and indicated that the training was helpful for dental practice.

CONCLUSIONS

The implementation of a digital workflow in undergraduate dental education is feasible and has acceptable clinical results. However, CAD is time-intensive, and the experience can be challenging.

Pre‐doctoral dental students’ computer‐aided design/computer‐aided manufacturing‐related education, knowledge, attitudes and behavior: A national survey

OBJECTIVES

Computer-aided design/computer-aided manufacturing (CAD/CAM) technology transformed the world of restorative dentistry. The objectives were to assess pre-doctoral dental students' CAD/CAM-related education, knowledge, attitudes, and professional behavior, and to explore the relationships between the year in dental school and these constructs.

METHODS

A total of 358 pre-doctoral dental students from 17 of the 68 US dental schools responded to a web-based anonymous survey.

RESULTS

CAD/CAM-related classroom-based education was likely to happen in lectures (87.2%) and simulated exercises as part of a class (86.9%). Faculty were most likely to provide CAD/CAM instruction (87.9%), with staff (44.8%) and dental technicians (20.2%) being engaged as well. Preclinical education included video demonstrations (81.8%), demonstrations during a lecture (76.4%) or for smaller groups of students (69.2%), hands-on workshops (65.6%), and individual instruction (50.4%). Considering the digital workflow in clinics, 45.2% reported using intraoral scans. The more advanced the students were in their program, the more CAD/CAM knowledge (r = 0.27; p < 0.001) and knowledge about what can be fabricated with CAD/CAM technology they had (r = 0.25; p < 0.001). However, the student's satisfaction with the education about CAD/CAM did not increase over the years (r = -0.04; n.s.) and remained neutral, while their attitudes became more positive the longer they were in dental school (r = 0.13; p < 0.05). Their attitudes were quite positive, with most students considering that CAD/CAM is the future of dentistry (5 = most positive: Mean = 4.34), agreeing that they enjoyed working with CAD/CAM (Mean = 4.11) and that CAD/CAM has the potential of making them a better dentist (Mean = 4.07).

CONCLUSIONS

The majority of students in the US dental schools appreciate CAD/CAM technology, consider it to be the future of dentistry, and believe it makes them better dentists. The fact that the majority is not satisfied with their classroom-based, preclinical and clinical CAD/CAM-related education should therefore be a call to action to rethink dental school curricula in this content area.

Development of an artificial intelligence-based algorithm to classify images acquired with an intraoral scanner of individual molar teeth into three categories

Background

Forensic dentistry identifies deceased individuals by comparing postmortem dental charts, oral-cavity pictures and dental X-ray images with antemortem records. However, conventional forensic dentistry methods are time-consuming and thus unable to rapidly identify large numbers of victims following a large-scale disaster.

Objective

Our goal is to automate the dental filing process by using intraoral scanner images. In this study, we generated and evaluated an artificial intelligence-based algorithm that classified images of individual molar teeth into three categories: (1) full metallic crown (FMC); (2) partial metallic restoration (In); or (3) sound tooth, carious tooth or non-metallic restoration (CNMR).

Methods

A pre-trained model was created using oral-cavity pictures from patients. Then, the algorithm was generated through transfer learning and training with images acquired from cadavers by intraoral scanning. Cross-validation was performed to reduce bias. The ability of the model to classify molar teeth into the three categories (FMC, In or CNMR) was evaluated using four criteria: precision, recall, F-measure and overall accuracy.

Results

The average value (variance) was 0.952 (0.000140) for recall, 0.957 (0.0000614) for precision, 0.952 (0.000145) for F-measure, and 0.952 (0.000142) for overall accuracy when the algorithm was used to classify images of molar teeth acquired from cadavers by intraoral scanning.

Conclusion

We have created an artificial intelligence-based algorithm that analyzes images acquired with an intraoral scanner and classifies molar teeth into one of three types (FMC, In or CNMR) based on the presence/absence of metallic restorations. Furthermore, the accuracy of the algorithm reached about 95%. This algorithm was constructed as a first step toward the development of an automated system that generates dental charts from images acquired by an intraoral scanner. The availability of such a system would greatly increase the efficiency of personal identification in the event of a major disaster.

Dental students' preference and perception on intraoral scanning and impression making

BACKGROUND

To investigate the preference and perception on intraoral scanning and impression making among dental students.

METHODS

Final-year dental students from the 2019 and 2020 cohorts were invited to complete an online questionnaire via Google-Form. Their preference on the intraoral-scanning/impression making techniques and their perception on these techniques including the ease of defect identification, ease of infection control, need of chairside support, ease to master the technique as a beginner, efficiency in their hands and ease to handle the scanner software (yes/no) were collected. The results were analysed using McNemar tests and binary logistic regression test. All tests were performed at significance level α = 0.05.

RESULTS

Ninety-seven students participated in this study with a response rate of 96.0 %. Eighty-one students (83.5 %) have tried intraoral scanning on peers. Fifty-three (54.6 %) students preferred intraoral-scanning and were categorized as Pro-scanning group. Forty-four (45.4 %) students either preferred impression-making (n = 21) or not sure (n = 23) were categorized as Others. More than half of students in both groups felt that intraoral-scanning is easier to identify defect, easier in infection control and require less chairside support. Higher proportion of students in the Pro-scanning group felt that intraoral-scanning requires less chairside support, easier to master as a beginner, more efficient in their hands and they can deal well with the scanner software than that in Others (P < 0.05). Regression shown that students preferred a technique that they perceived is more efficient (P = 0.000).

CONCLUSIONS

While intraoral scanning has perceived advantages, many students still prefer impression making that works more efficient to them.

Clinical Evaluation of Resin Composite CAD/CAM Restorations Placed by Undergraduate Students

To evaluate the clinical outcomes of resin composite CAD/CAM restorations in a prospective cohort study, and to assess patient and operator satisfaction after restoration placement, 59 indirect resin composite were placed by supervised undergraduate students, of which 43 restorations were followed over a mean period of 28 months (14–44 months) and evaluated using USPHS criteria. Patient and operator satisfaction levels were assessed using a visual analogue scale (VAS) after restoration placement. A total of 37 patients and 47 restorations were included for further study. Four teeth were extracted—three due to extensive drug-induced secondary caries in the same patient, and one tooth due to large periapical periodontitis after 44 months of service. The overall survival rate was 91.4%, and success rate was 87.2%. Differences between baseline and endpoint scores were significant for marginal discoloration (p < 0.05) and adaptation (p < 0.001). Color match (p < 0.05) and surface texture (p < 0.001) differed significantly, affecting all restoration types. VAS scores for patient and operator satisfaction showed a significant rank correlation (p < 0.01), and pairwise comparison showed significant differences for mean overall patient and operator VAS scores (p < 0.001). Lava Ultimate CAD/CAM may be considered a suitable material for overlays and endocrown restorations when combined with IDS, air abrasion, and MDP-containing adhesive systems. Marginal disintegration may present in inlays and onlays over time.

The dentist will scan you now: The next generation of digital-savvy graduates

INTRODUCTION

Undergraduate dental curriculum consisting of digital tools is essential in today's era of modern dentistry. The aim of this study was to evaluate final-year undergraduate dental students' perception of using intraoral scanners and the feasibility of increasing exposure to intraoral scanners in their undergraduate programme.

MATERIALS AND METHODS

Forty students volunteered to complete one maxillary conventional and optical impression (TRIOS 3, 3Shape A/S). Questionnaires were used to assess their familiarity, perceived confidence levels, difficulties and user-friendliness of each technique using a visual analogue scale prior to and after experiencing each impression technique.

RESULTS

Students felt more familiar with conventional (C) than digital (D) impressions (P = .00). Their pre-confidence level was also higher with the conventional method (C: 80.9 ± 15.5; D: 39.6 ± 25.5); however, the post-confidence level significantly increased for the digital impression technique (P = .00). Participants perceived conventional technique to be easier (P = .02) and faster than optical impressions (P = .03). User-friendliness of the intraoral scanner scored moderate (67.7 ± 22.9). The difference in the mean total working time was not significant (P = .05). Forty per cent of participants indicated that they preferred using the digital impression technique.

CONCLUSIONS

Although final-year undergraduate students still perceived the conventional impression technique to be easier and faster than digital scanning, there was a significant increase in the level of confidence by this cohort after only one occasion of clinical optical impressions. Undergraduate dental students are ready to uptake new technology, and it should be strongly considered to incorporate more digital scanning during their training.

Operators matter - An assessment of the expectations, perceptions, and performance of dentists, postgraduate students, and dental prosthetist students using intraoral scanning

OBJECTIVE

to assess the expectations, perceptions and performance of different operators with varying backgrounds and training in the use of full-arch intraoral scanning (IOS).

METHODS AND MATERIALS

Dentists (DENT), postgraduate dental students (DPG), and student prosthetists (PROS) were invited to join an IOS training workshop. Participants completed a satisfactory scan of a mannikin-mounted typodont with the total scanning time (TST) recorded. They also completed anonymised pre and post-training questionnaires covering their background, and IOS expectations and experience. Statistical analysis was performed using the Mann-Whitney U, Kruskal Wallis, and chi-square tests. Open-ended questions were analysed manually and using Leximancer.

RESULTS

Twenty-seven participants were recruited: 10 DENT; 10 PROS; and 7 DPG. Positive expectations of IOS was reported by 93 % of participants. Combined TST was 285 ± 83 s, with the PROS TST significantly longer (p < 0.05, 337 ± 79 s). Further training need was reported by 60 % of PROS and 50 % of DENT versus 14 % of DPG. Positive IOS experience was reported by 96 % of participants, 74 % perceived it to be accurate, and 63 % found it easy to use. Eighty-five percent of all participants stated that cost would influence their decision of adopting IOS in their practice.

CONCLUSION

Expectations and perceptions of IOS were overwhelmingly positive, irrespective of operator background and experience. Scanning performance and training needs depended on the operator's background. Cost of IOS remains a barrier to acquiring the technology.

CLINICAL SIGNIFICANCE

IOS training must be customised to accommodate the needs of different operators. The cost of IOS needs revision to improve its accessibility.

Accuracy and Precision Evaluation of International Standard Spherical Model by Digital Dental Scanners

With the popularization of digital technology and the exposure of traditional technology's defects, computer-aided design and computer-aided manufacturing (CAD/CAM) has been widely used in the field of dentistry. And the accuracy of the scanning system determines the ultimate accuracy of the prosthesis, which is a very important part of CAD/CAM, so we decided to evaluate the accuracy of the intraoral and extraoral scanners. In this study, we selected the sphere model as the scanning object and obtained the final result through data analysis and 3D fitting. In terms of trueness and precision, the scanner of SHINING was significantly different from that of others; however, there was no significant difference between TRIOS and CEREC. SHINING showed the lowest level of accuracy, with CEREC slightly lower than TRIOS. The sphere model has also been proven to be scanned successfully.