Use of 3D printed models in student education of craniofacial traumas

3D printing materials and 3D printed surgical devices in oral and maxillofacial surgery: design, workflow and effectiveness

Oral and maxillofacial surgery is a specialized surgical field devoted to diagnosing and managing conditions affecting the oral cavity, jaws, face and related structures. In recent years, the integration of 3D printing technology has revolutionized this field, offering a range of innovative surgical devices such as patient-specific implants, surgical guides, splints, bone models and regenerative scaffolds. In this comprehensive review, we primarily focus on examining the utility of 3D-printed surgical devices in the context of oral and maxillofacial surgery and evaluating their efficiency. Initially, we provide an insightful overview of commonly utilized 3D-printed surgical devices, discussing their innovations and clinical applications. Recognizing the pivotal role of materials, we give consideration to suitable biomaterials and printing technology of each device, while also introducing the emerging fields of regenerative scaffolds and bioprinting. Furthermore, we delve into the transformative impact of 3D-printed surgical devices within specific subdivisions of oral and maxillofacial surgery, placing particular emphasis on their rejuvenating effects in bone reconstruction, orthognathic surgery, temporomandibular joint treatment and other applications. Additionally, we elucidate how the integration of 3D printing technology has reshaped clinical workflows and influenced treatment outcomes in oral and maxillofacial surgery, providing updates on advancements in ensuring accuracy and cost-effectiveness in 3D printing-based procedures.

Visuospatial abilities and 3D-printed based learning

PURPOSE

The use of 3D-printing in every field of medicine is expanding, notably as an educational tool. The aim of this study was to assess how visuospatial abilities (VSA) of students may impact learning helped with 3D-printed models.

METHODS

Participants were undergraduate medical school students during their clinical rotation in oral and maxillofacial surgery in two French Universities. Students were included prospectively and consecutively from September 2021 to June 2023. First, a lecture about craniosynostosis was performed with the help of 3D-printed models of craniosynostotic skulls. Then, a mental rotation test (MRT) followed by a multiple-choice questions (MCQs) form about craniosynostosis presentations were submitted to the students.

RESULTS

Forty undergraduate students were finally included. Median MRT score was 15 (10.75;21) and median score to the MCQs was 13 (11.75;14). There was a significantly weak correlation between the MRT-A score and the score to the MCQs (rs = 0.364; p = 0.022). A simple linear regression was calculated to predict the result to the MCQs on MRT-A score [ (F(1,39) = 281.248; p < 0.0001), with a R2 of 0.878 ].

CONCLUSION

This study showed that VSA has an impact on the recognition of complex clinical presentations, i.e. skulls with craniosynostosis. The correlation found between VSA and complex 3D shape recognition after learning aided with 3D-printed model is emphasizing the importance of VSA when using innovative technologies. Thus, VSA training should be envisioned during the curriculum.

3D-printed model for gingival flap surgery simulation: Development and pilot test

INTRODUCTION

To assess the feasibility of a realistic model for learning oral flaps using 3D printing technology.

MATERIALS AND METHODS

A mould was designed to reproduce the mandibular gingival mucosa, and a mandibular model was created using a three-dimensional printer for training undergraduate students to perform gingival flaps. After a short interview about its use, the participants were asked to use the simulator and provide feedback using a 5-point Likert questionnaire.

RESULTS

The 3D-printed oral surgery flap training model was practical and inexpensive. The model was very realistic, educational and useful for hands-on training.

CONCLUSIONS

3D printing technology offers new possibilities for training in dental treatments that are currently difficult to replicate. The use of this simulator for oral flap surgery was well-received and considered promising by the participants.

Adoption of additive manufacturing in oral and maxillofacial surgery among university and non-university hospitals in Sweden: findings from a nationwide survey

PURPOSE

Additive manufacturing (AM) is an innovative printing technology that can manufacture 3-dimensional solid objects by adding layers of material from model data. AM in oral and maxillofacial surgery (OMFS) provides several clinical applications such as surgical guides and implants. However, the adoption of AM in OMFS is not well covered. The purpose was to study the adoption of AM in OMFS in university and non-university hospitals in Sweden. Three research questions were addressed: What is the degree of using AM solutions in university and non-university hospitals?; What are AM solutions used?; How are the AM solutions accessed (production mode) in university hospitals and non-university hospitals?

METHODS

A survey was distributed to OMF surgeons in Sweden. The questionnaire consisted of 16 questions. Data were analyzed through descriptive and content analysis.

RESULTS

A total of 14 university and non-university hospitals were captured. All 14 hospitals have adopted AM technology and 11 of the hospitals adopted AM in OMFS. Orthognathic and trauma surgery are two major types of surgery that involve AM technology where material extrusion and vat polymerization are the two most used AM technologies in OMFS. The primary application of AM was in medical models and guides.

CONCLUSION

Majority of Swedish university hospitals and non-university hospitals have adopted AM in OMFS. The type of hospital (university or non-university hospital) has no impact on AM adoption. AM in OMFS in Sweden can be perceived to be a mature clinical application.

Evaluation of a 3D-printed hands-on radius fracture model during teaching courses

OBJECTIVE

This study aimed to evaluate the effectiveness of a 3D-printed hands-on radius fracture model for teaching courses. The model was designed to enhance understanding and knowledge of radius fractures among medical students during their clinical training.

METHODS

The 3D models of radius fractures were generated using CT scans and computer-aided design software. The models were then 3D printed using Fused-Filament-Fabrication (FFF) technology. A total of 170 undergraduate medical students participated in the study and were divided into three groups. Each group was assigned one of three learning aids: conventional X-ray, CT data, or a 3D-printed model. After learning about the fractures, students completed a questionnaire to assess their understanding of fracture mechanisms, ability to assign fractures to the AO classification, knowledge of surgical procedures, and perception of the teaching method as well as the influence of such courses on their interest in the specialty of trauma surgery. Additionally, students were tested on their ability to allocate postoperative X-ray images to the correct preoperative image or model and to classify them to the AO classification.

RESULTS

The 3D models were well received by the students, who rated them as at least equal or better than traditional methods such as X-ray and CT scans. Students felt that the 3D models improved their understanding of fracture mechanisms and their ability to explain surgical procedures. The results of the allocation test showed that the combination of the 3D model and X-ray yielded the highest accuracy in classifying fractures according to the AO classification system, although the results were not statistically significant.

CONCLUSION

The 3D-printed hands-on radius fracture model proved to be an effective teaching tool for enhancing students' understanding of fracture anatomy. The combination of 3D models with the traditional imaging methods improved students' ability to classify fractures and allocate postoperative images correctly.

Full-sized realistic 3D printed models of liver and tumour anatomy: a useful tool for the clinical medicine education of beginning trainees

BACKGROUND

Simulation-based medical education (SBME) and three-dimensional printed (3DP) models are increasingly used in continuing medical education and clinical training. However, our understanding of their role and value in improving trainees' understanding of the anatomical and surgical procedures associated with liver surgery remains limited. Furthermore, gender bias is also a potential factor in the evaluation of medical education. Therefore, the aim of this study was to evaluate the educational benefits trainees receive from the use of novel 3DP liver models while considering trainees' experience and gender.

METHODS

Full-sized 3DP liver models were developed and printed using transparent material based on anonymous CT scans. We used printed 3D models and conventional 2D CT scans of the liver to investigate thirty trainees with various levels of experience and different genders in the context of both small group teaching and formative assessment. We adopted a mixed methods approach involving both questionnaires and focus groups to collect the views of different trainees and monitors to assess trainees' educational benefits and perceptions after progressing through different training programs. We used Objective Structured Clinical Examination (OSCE) and Likert scales to support thematic analysis of the responses to the questionnaires by trainees and monitors, respectively. Descriptive analyses were conducted using SPSS statistical software version 21.0.

RESULTS

Overall, a 3DP model of the liver is of great significance for improving trainees' understanding of surgical procedures and cooperation during operation. After viewing the personalized full-sized 3DP liver model, all trainees at the various levels exhibited significant improvements in their understanding of the key points of surgery (p < 0.05), especially regarding the planned surgical procedure and key details of the surgical procedures. More importantly, the trainees exhibited higher levels of satisfaction and self-confidence during the operation regardless of gender. However, with regard to gender, the results showed that the improvement of male trainees after training with the 3DP liver model was more significant than that of female trainees in understanding and cooperation during the surgical procedure, while no such trend was found with regard to their understanding of the base knowledge.

CONCLUSION

Trainees and monitors agreed that the use of 3DP liver models was acceptable. The improvement of the learning effect for practical skills and theoretical understanding after training with the 3DP liver models was significant. This study also indicated that training with personalized 3DP liver models can improve all trainees' presurgical understanding of liver tumours and surgery and males show more advantage in understanding and cooperation during the surgical procedure as compared to females. Full-sized realistic 3DP models of the liver are an effective auxiliary teaching tool for SBME teaching in Chinese continuing medical education.

Three-Dimensional printed model for preclinical training in oral radiology

INTRODUCTION

3D printing is experiencing significant growth in the teaching and learning process. This study aims to present a 3D printed skull model for preclinical intraoral radiographic practice.

MATERIALS AND METHODS

Two 3D printed mannequins were created. One mannequin used an STL file of a skull that was edited using two 3D modelling software (Meshmixer and Netfabb). The second mannequin was designed directly from a patient's segmented CBCT data and then converted into an STL file. Both mannequins were printed using fused deposition modelling (FDM) technology and polylactic acid (PLA) filament; teeth for the second mannequin were also printed using digital light processing (DLP). The printed skull bones were attached, the mandible was articulated to the articular fossa of the temporal bone, and the teeth were inserted into the alveoli. Intraoral radiographs of both mannequins were taken using a digital sensor (RVG 5100, Carestream).

RESULTS

Both 3D printed mannequins showed satisfactory radiographic appearance, allowing geometric representation of each intraoral radiographic projection, regardless of STL file origin. Anatomical structures, such as the periodontal ligament space, zygomatic process of the maxilla and intermaxillary suture, were represented. The material cost of the first and second printed prototype was $34.00 and $39.00, respectively.

CONCLUSIONS

The use of 3D printed models is presented as an alternative to artificial commercial phantoms for the preclinical training of intraoral radiographic techniques through the combined benefits of superior radiographic projection quality, the possibility of model manipulation and an affordable price.

Clear guidance to select the most accurate technologies for 3D printing dental models - A network meta-analysis

OBJECTIVES

Thus far, the findings of numerous studies conducted on the accuracy of three-dimensional (3D) printed dental models are conflicting. Therefore, the aim of the network meta-analysis (NMA) is to determine the accuracy of 3D printed dental models compared with digital reference models.

DATA

Studies comparing the accuracy of 3D printed full-arch dental models manufactured using different printing techniques to initial STL files were included.

SOURCES

This study was registered in PROSPERO (CRD42021285863). An electronic search was performed across four databases in November 2021, and search was restricted to the English language.

STUDY SELECTION

A systematic search was conducted based on a prespecified search query. 16,303 articles were pooled after the removal of the duplicates. Following study selection and data extraction, 11 eligible studies were included in the NMA in 6 subgroups. The outcomes were specified as trueness and precision and expressed as root mean square (RMS) and absolute mean deviation values. Seven printing technologies were analyzed: stereolithography (SLA), digital light processing (DLP), fused deposition modeling/fused filament fabrication (FDM/FFF), MultiJet, PolyJet, continuous liquid interface production (CLIP), and LCD technology. The QUADAS-2 and GRADE were used to evaluate the risk of bias and certainty of evidence.

CONCLUSIONS

SLA, DLP, and PolyJet technologies were the most accurate in producing precise full-arch dental models.

CLINICAL SIGNIFICANCE

The findings of the NMA suggest that SLA, DLP, and PolyJet technologies are sufficiently accurate for full-arch dental model production for prosthodontic purposes. In contrast, FDM/FFF, CLIP, and LCD technologies are less suitable for manufacturing dental devices.

Efficacy of three-dimensional models for medical education: A systematic scoping review of randomized clinical trials

To estimate the efficacy of three-dimensional (3D) models for medical education.

METHODS

A systematic scoping review was performed containing diverse databases such as SCOPUS, PubMed/MEDLINE, SCIELO, and LILACS. MeSH terms and keywords were stipulated to explore randomized clinical trials (RCTs) in all languages. Solely RCTs that accomplished the eligibility criteria were admitted.

RESULTS

Fifteen RCTs including 1659 medical students were chosen. Five RCTs studied heart models, 3 RCTs explored facial, spinal and bone fractures and the rest of the trials investigated eye, arterial, pelvic, hepatic, chest, skull, and cleft lip and palate models. Regarding the efficacy of 3D models, in terms of learning skills and knowledge gained by medical students, most RCTs reported higher scores. Considering the test-taking times, the results were variable. Two RCTs showed less time for the 3D group, another RCT indicated variable results in the response times of the test depending on the anatomical zone evaluated, while another described that the students in the 3D group were slightly quicker to answer all questions when compared with the traditional group, but without statistical significance. The other 11 experiments did not present results about test-taking times. Most students in all RCTs indicated satisfaction, enjoyment, and interest in utilizing the 3D systems, and recognized that their abilities were enhanced.

CONCLUSIONS

Higher efficacy in terms of learning skills and knowledge gained was observed when the 3D systems were used by medical students. Undergraduates also expressed great satisfaction with the use of these technologies. Regarding the test-taking times, the results favored the 3D group.

Introduction of 3D Printing in a German Municipal Hospital-Practice Guide for CMF Surgery

Study Design

This study aimed to introduce 3D printing in a municipal hospital to improve the treatment of craniomaxillofacial patients and optimize costs and operating time. Thus we describe the implementation of low-cost in-house 3D printing to facilitate orbital- and mandible reconstruction in CMF surgery. Moreover, we address legal requirements, safety at work, fire- and data protection. Finally, we want to share our experiences using 3D printing and point out its advantages in providing better patient care.

Methods

We outline the setup of in-house 3D printing and focus on obeying German health care regulations. We based our approach on a fused deposition modeling 3D printer and free software. As proof of concept, we treated 4 cases of severe orbital trauma and 1 case of mandibular reconstruction. We printed a 3D patient-specific model for each case and adapted a titanium mesh implant, respectively, a titanium reconstruction plate before performing the surgery.

Results

Our approach reduced costs, duration of anesthesia, operating time, recovery time, and postoperative swelling and increased the revenue. Functional outcome in orbital reconstruction like eye movement and double vision, was improved compared to the conventional technique. No severe complications like loss-of-vision or surgical revision occurred. Likewise, mandibular reconstruction showed no plate loosening or plate fracture.

Conclusion

The implementation of cost-efficient 3D printing resulted in successful patient treatment with excellent outcomes. Our practice guide offers a 3D printing workflow and could be adapted to fit the needs of other specialties like neurosurgery, orthopedic surgery as well.

Dental trauma simulation training using four splinting models: A cross sectional study

BACKGROUND/AIM

Opportunities for dental students to obtain clinical experience in the management of traumatic dental injuries are scarce, and most dentists encounter difficulties with their first trauma patients after graduation. The aim of this study was to question students on the ease of handling of four types of flexible splints, with two common methods of bonding to the tooth.

MATERIAL AND METHODS

A total of 161 fourth year dental students completed a simulated treatment of an avulsed tooth using orthodontic wire, Twistflex wire, nylon fishing line, and Powermesh as splints. The bonding materials were composite resin (Spectra ST LV) or glass ionomer cement (GC Fuji LC Ortho). The students then answered 16 questions on a 5-point Likert scale, or with an open answer field.

RESULTS

Most students agreed (48.8%) or strongly agreed (31.3%) that the simulated trauma exercise assisted their learning. There was strong agreement (68.8%) and agreement (28.7%) that the simulation added value to their dental training compared to didactic training only. Similarly, 52.3% of participants strongly agreed and 40% agreed that they felt engaged in the learning activity. Only 53.8% of the participants agreed and 7.5% strongly agreed that the simulation felt realistic. Most students (56.2%) found a Powermesh/composite splint was the easiest to place, and nylon fishing line/GC Fuji LC Ortho splints was the least difficult to remove (35%).

CONCLUSION

Wire-free splints with composite bonding were judged as the easiest to place by students, while glass ionomer cement was the easiest to remove.

Three-dimensional printing models improves long-term retention in medical education of pathoanatomy: A randomized controlled study

INTRODUCTION

Craniosynostosis is a rare and complex pathology, and visuospatial skills are necessary for a good understanding of the condition. While the use of three-dimensional (3D) models has improved the understanding of complex craniofacial anatomy, no study has evaluated the impact of this teaching support on long-term retention.

MATERIALS AND METHODS

Our randomized controlled trial was designed to compare the long-term retention of information with 3D-printed models of four types of craniosynostosis versus classic 3D reconstructions displayed in two-dimensional (2D) among undergraduate students. All students benefited from the same standardized course followed by the manipulation of the learning tool associated with the group for 15 minutes. Long-term retention was assessed by the capability to properly recognize different types of craniosynostosis 3 weeks after the course.

RESULTS

Eighty-five students were enrolled. Previous educational achievements and baseline visuospatial skills were similar between the groups. The bivariate analysis showed the mean score in the 3D and 2D groups were 11.32 (2.89) and 8.08 (2.81), respectively (p < 0.0001).

CONCLUSIONS

3D-printed models of structures with spatial complexity such as various craniosynostosis patterns improve significantly medical students' long-term retention, indicating their educational efficacy.

Anatomical Engineering and 3D Printing for Surgery and Medical Devices: International Review and Future Exponential Innovations

Three-dimensional printing (3DP) has recently gained importance in the medical industry, especially in surgical specialties. It uses different techniques and materials based on patients' needs, which allows bioprofessionals to design and develop unique pieces using medical imaging provided by computed tomography (CT) and magnetic resonance imaging (MRI). Therefore, the Department of Biology and Medicine and the Department of Physics and Engineering, at the Bioastronautics and Space Mechatronics Research Group, have managed and supervised an international cooperation study, in order to present a general review of the innovative surgical applications, focused on anatomical systems, such as the nervous and craniofacial system, cardiovascular system, digestive system, genitourinary system, and musculoskeletal system. Finally, the integration with augmented, mixed, virtual reality is analyzed to show the advantages of personalized treatments, taking into account the improvements for preoperative, intraoperative planning, and medical training. Also, this article explores the creation of devices and tools for space surgery to get better outcomes under changing gravity conditions.

Three-Dimensional Printing Model Enhances Craniofacial Trauma Teaching by Improving Morphologic and Biomechanical Understanding: A Randomized Controlled Study

BACKGROUND

Teaching about craniofacial traumas is challenging given the complexity of the craniofacial anatomy and the necessity for good spatial representation skills. To solve these problems, three-dimensional printing seems to be an appropriate educative material. In this study, the authors conducted a randomized controlled trial. The authors' main objective was to compare the performance of the undergraduate medical students in an examination based on the teaching support: three-dimensionally printed models versus two-dimensional pictures.

METHODS

All participants were randomly assigned to one of two groups using a random number table: the three-dimensionally-printed support group (three-dimensional group) or the two-dimensionally-displayed support group (two-dimensional group). All participants completed a multiple-choice question evaluation questionnaire on facial traumatology (first, a zygomatic bone fracture; then, a double mandible fracture). Sex and potential confounding factors were evaluated.

RESULTS

Four hundred thirty-two fifth-year undergraduate medical students were enrolled in this study. Two hundred six students were allocated to the three-dimensional group, and 226 were allocated to the two-dimensional group. The three-dimensionally printed model was considered to be a better teaching material compared with two-dimensional support. The global mean score was 2.36 in the three-dimensional group versus 1.99 in the two-dimensional group (p = 0.008). Regarding teaching of biomechanical aspects, three-dimensionally-printed models provide better understanding (p = 0.015). Participants in both groups exhibited similar previous student educational achievements and visuospatial skills.

CONCLUSIONS

This prospective, randomized, controlled educational trial demonstrated that incorporation of three-dimensionally-printed models improves medical students' understanding. This trial reinforces previous studies highlighting academic benefits in using three-dimensionally-printed models mostly in the field of understanding complex structures.

3D Printing of Physical Organ Models: Recent Developments and Challenges

Physical organ models are the objects that replicate the patient-specific anatomy and have played important roles in modern medical diagnosis and disease treatment. 3D printing, as a powerful multi-function manufacturing technology, breaks the limitations of traditional methods and provides a great potential for manufacturing organ models. However, the clinical application of organ model is still in small scale, facing the challenges including high cost, poor mimicking performance and insufficient accuracy. In this review, the mainstream 3D printing technologies are introduced, and the existing manufacturing methods are divided into "directly printing" and "indirectly printing", with an emphasis on choosing suitable techniques and materials. This review also summarizes the ideas to address these challenges and focuses on three points: 1) what are the characteristics and requirements of organ models in different application scenarios, 2) how to choose the suitable 3D printing methods and materials according to different application categories, and 3) how to reduce the cost of organ models and make the process simple and convenient. Moreover, the state-of-the-art in organ models are summarized and the contribution of 3D printed organ models to various surgical procedures is highlighted. Finally, current limitations, evaluation criteria and future perspectives for this emerging area are discussed.

Prenatal diagnosis of isolated lateral facial cleft by ultrasonography and three-dimensional printing: A case report

BACKGROUND

Lateral facial clefts are atypical with a low incidence in the facial cleft spectrum. With the development of ultrasonography (US) prenatal screening, such facial malformations can be detected and diagnosed prenatally rather than at birth. Although three-dimensional US (3DUS) can render the fetus' face via 3D reconstruction, the 3D images are displayed on two-dimensional screens without field depth, which impedes the understanding of untrained individuals. In contrast, a 3D-printed model of the fetus' face helps both parents and doctors develop a more comprehensive understanding of the facial malformation by creating more interactive aspects. Herein, we present an isolated lateral facial cleft case that was diagnosed via US combined with a 3D-printed model.

CASE SUMMARY

A 31-year-old G2P1 patient presented for routine prenatal screening at the 22^nd wk of gestation. The coronal nostril-lip section of two-dimensional US (2DUS) demonstrated that the fetus' bilateral oral commissures were asymmetrical, and left oral commissure was abnormally wide. The left oblique-coronal section showed a cleft at the left oral commissure which extended to the left cheek. The results of 3DUS confirmed the cleft. Furthermore, we created a model of the fetal face using 3D printing technology, which clearly presented facial malformations. The fetus was diagnosed with a left lateral facial cleft, which was categorized as a No. 7 facial cleft according to the Tessier facial cleft classification. The parents terminated the pregnancy at the 24^th wk of gestation after parental counseling.

CONCLUSION

In the diagnostic course of the current case, in addition to the traditional application of 2D and 3DUS, we created a 3D-printed model of the fetus, which enhanced diagnostic evidence, benefited the education of junior doctors, improved parental counseling, and had the potential to guide surgical planning.

In-house 3D printing: Why, when, and how? Overview of the national French good practice guidelines for in-house 3D-printing in maxillo-facial surgery, stomatology, and oral surgery

3D-printing is part of the daily practice of maxillo-facial surgeons, stomatologists and oral surgeons. To date, no French health center is producing in-house medical devices according to the new European standards. Based on all the evidence-based data available, a group of experts from the French Society of Stomatology, Maxillo-Facial Surgery and Oral Surgery (Société Française de Chirurgie Maxillofaciale, Stomatologie et Chirurgie Orale, SFSCMFCO), provide good practice guidelines for in-house 3D-printing in maxillo-facial surgery, stomatology, and oral surgery. Briefly, technical considerations related to printers and CAD software, which were the main challenges in the last ten years, are now nearly trivial questions. The central current issues when planning the implementation of an in-house 3D-printing platform are economic and regulatory. Successful in-house 3D platforms rely on close collaborations between health professionals and engineers, backed by regulatory and logistic specialists. Several large-scale academic projects across France will soon provide definitive answers to governance and economical questions related to the use of in-house 3D printing.

Surgical training 2.0: A systematic approach reviewing the literature focusing on oral maxillofacial surgery - Part I

PURPOSE

Many technologies are emerging in the medical field. Having an overview of the technological arsenal available to train new surgeons seems very interesting to guide subsequent surgical training protocols.

METHODS

This article is a systematic approach reviewing new technologies in surgical training, in particular in oral and maxillofacial surgery. This review explores what new technologies can do compared to traditional methods in the field of surgical education. A structured literature search of PubMed was performed in adherence to PRISMA guidelines. The articles were selected when they fell within predefined inclusion criteria while respecting the key objectives of this systematic review. We looked at medical students and more specifically in surgery and analysed whether exposure to new technologies improved their surgical skills compared to traditional methods. Each technology is reviewed by highlighting its advantages and disadvantages and studying the feasibility of integration into current practice.

RESULTS

The results are encouraging. Indeed, all of these technologies make it possible to reduce the learning time, the operating times, the operating complications and increase the enthusiasm of the students compared to more conventional methods. The start-up cost, the complexity to develop new models, and the openness of mind necessary for the integration of these technologies are all obstacles to immediate development. The main limitations of this review are that many of the studies have been carried out on small numbers, they are not interested in acquiring knowledge or skills over the long term and obviously there is a publication bias.

CONCLUSION

Surgical education methods will probably change in the years to come, integrating these new technologies into the curriculum seems essential so as not to remain on the side. This first part therefore reviews, open field camera, telemedicine and 3D printing. This systematic review is registered on PROSPERO.

Surgical planning using facial fracture 3D models: The role of cyanoacrylate glue and miniplating for anatomical reduction

Background

In comminuted facial fractures, peri-operative use of 3D-printed life size models is increasingly a useful adjunct. It allows for preoperative surgical rehearsal and plate bending, to achieve anatomical reduction with reduced operative time and cost. One problem encountered is difficulty contouring the fixation plate whilst maintaining the relative spatial orientation of comminuted fragments. This paper shares an effective method of overcoming this problem.

Methods

All comminuted facial fracture patients underwent counselling for 3D printing. Pre-printing thresholding and segmentation of each fragment (as directed by the surgeon) were done by the radiologist and the engineering team, using the multi-slice CT Face DICOM data. Life-size 3D-resin models of the fractures were printed. Fast-acting medium consistency cyanoacrylate glue (Zap-A-Gap^Ⓡ) and miniplates were used to assemble the printed model segments in ‘anatomic reduction’. Aerosolized alcohol accelerator facilitated immediate glue curing, providing a stable model. The plates were adapted over this restored neonative 3D construct with bending inserts, sterilized and used intraoperatively. The 3D model was used to guide the operative sequence. Intraoperative CT was used in select cases to confirm anatomic reduction.

Results/Complications

All patients (n = 5) had comminuted fractures in at least one of the bony units (mandible, maxilla or orbits) and one was a pan-facial fracture case. 3D printed models aided fracture reduction and fixation, whilst avoiding the guesswork in ascertaining the contour of the mandibular arch. In addition, the pre-contoured mandible plates restored premorbid occlusion and projection, without the need for long-term archbars in all cases. Operative time was estimated to be reduced by 0.5–1 h. Resident teaching was enhanced by this approach.

Conclusion

The application of medium consistency fast-acting cyanoacrylate glue and miniplates facilitated the creation of the premorbid facial skeletal model and allowed pre-bending of the plates, thus saving operative time and cost.

Dental 3D-Printing: Transferring Art from the Laboratories to the Clinics

The rise of three-dimensional (3D) printing technology has changed the face of dentistry over the past decade. 3D printing is a versatile technique that allows the fabrication of fully automated, tailor-made treatment plans, thereby delivering personalized dental devices and aids to the patients. It is highly efficient, reproducible, and provides fast and accurate results in an affordable manner. With persistent efforts among dentists for refining their practice, dental clinics are now acclimatizing from conventional treatment methods to a fully digital workflow to treat their patients. Apart from its clinical success, 3D printing techniques are now employed in developing haptic simulators, precise models for dental education, including patient awareness. In this narrative review, we discuss the evolution and current trends in 3D printing applications among various areas of dentistry. We aim to focus on the process of the digital workflow used in the clinical diagnosis of different dental conditions and how they are transferred from laboratories to clinics. A brief outlook on the most recent manufacturing methods of 3D printed objects and their current and future implications are also discussed.

The Challenge of Dental Education After COVID-19 Pandemic - Present and Future Innovation Study Design

The present work suggests research and innovation on the topic of dental education after the COVID-19 pandemic, is highly justified and could lead to a step change in dental practice. The challenge for the future in dentistry education should be revised with the COVID-19 and the possibility for future pandemics, since in most countries dental students stopped attending the dental faculties as there was a general lockdown of the population. The dental teaching has an important curriculum in the clinic where patients attend general dentistry practice. However, with SARS-CoV-2 virus, people may be reluctant having a dental treatment were airborne transmission can occur in some dental procedures. In preclinical dental education, the acquisition of clinical, technical skills, and the transfer of these skills to the clinic are extremely important. Therefore, dental education has to adapt the curriculum to embrace new technology devices, instrumentations systems, haptic systems, simulation based training, 3D printer machines, to permit validation and calibration of the technical skills of dental students.

Development and evaluation of an interdisciplinary teaching model via 3D printing

The investigation aimed to assess the feasibility of creating an interdisciplinary training model simulating endodontic, restorative as well as implantologic treatment procedures by using 3D printing technology. A CBCT scan of the mandible of a real patient was initially taken. The generated DICOM-data were converted to a STL-file, which was further processed to design spaces for exchangeable replica teeth, a bone segment and an adapter to fix the model in a mannequin's head. After the manufacturing process, the model was evaluated by dental students performing a root canal treatment, the insertion of a glass fibre post and the insertion of an implant. The workflow allowed a simple and cost-effective way of manufacturing a single model, which is suitable for several training scenarios in the fields of endodontics, prosthodontics and implantology. The model was rated as being comparable to the real patient situation and offers repetitive treatment simulations. The present workflow is a feasible way of using DICOM-data and 3D printing for an interdisciplinary training model. The dental schools can design models according to their own curriculum and put the focus on a patient centered education.

Three-Dimensional Printing of Prenatal Ultrasonographic Diagnosis of Cleft Lip and Palate: Presenting the Needed "Know-How" and Discussing Its Use in Parental Education

Parental prenatal counseling is of paramount significance since parents often experience an emotional crisis with feelings of disappointment and helplessness. Three-dimensional (3D) printed model of the unborn child's face presenting with cleft lip and palate, based on ultrasonographic information, could be used to provide visual 3D information, further enhancing the prospective parent's comprehension of their unborn child's pathology and morphology, helping them to be psychologically prepared and improving the communication with the caretaking team. Prospective parents appreciate if prenatal counseling is available with the most detailed information as well as additional resources. The technique necessary to create 3D models after ultrasonographic information is explained, and the related costs are evaluated. The use of such models in parental education is then discussed.

Cost Analysis for In-house versus Industry-printed Skull Models for Acute Midfacial Fractures

Industry-printed (IP) 3-dimensional (3D) models are commonly used for secondary midfacial reconstructive cases but not for acute cases due to their high cost and long turnaround time. We have begun using in-house (IH) printed models for complex unilateral midface trauma. We hypothesized that IH models would decrease cost and turnaround time, compared with IP models.