Production and educational value of anatomical megamoulages

Abstract

Background

Anatomy is a crucial aspect of biological sciences and medical education, playing a pivotal role in various clinical practices. To enhance the existing curriculum and improve students’ spatial understanding of anatomy, educators have explored the use of moulages. In a groundbreaking study conducted in 2022–2023, the effectiveness of megamoulages in enhancing the comprehensive understanding of anatomy among medical students at Gonabad and Kurdistan University of Medical Sciences was thoroughly assessed. The produced megamoulages are not simply larger than conventional moulages; rather, they present anatomical details more clearly, including maximum anatomical points, structures, and neuro-vascular relationships as described in reference books and articles, which were not adequately represented in previous models, and they are also hand-painted.

Methods

The production of megamoulages involved a comprehensive 20-month sequential process. Initially, a needs assessment questionnaire was administered to medical students, residents, medical faculty surgeons, and anatomists to evaluate the project’s feasibility and significance. Results revealed that the majority of respondents (88%) believed the production of megamoulages would facilitate anatomy education. Anatomical models were strategically selected based on their complexity and the unavailability of similar models from foreign companies. Megamoulages (two groups of megamoulages: the first includes unique models, such as a sectional megamoulage of the brainstem that displays all structures in detail, while the second group (cerebellum and mandible) as improved quality models, which are similar to existing ones) were designed using 3D software, printed in sections, and assembled with magnets. The completed moulages were subjected to thorough evaluations following Kirkpatrick’s model, which included methods such as smile sheets and scientific tests administered to randomly divided third-semester medical students in the mentioned universities.

Results

In both universities, student satisfaction with the use of megamoulages was significantly higher compared to conventional moulages (P < 0.05). Additionally, in a written test, students who utilized megamoulages achieved an average score that was about 2.73 points higher than those who used conventional moulages (P < 0.05).

Conclusion

The implementation of megamoulages significantly enhanced the scores of anatomy learners. This study underscores the importance of innovative teaching tools, such as megamoulages, in improving anatomical education and increasing student satisfaction.

Introduction

Human anatomy explores the structures of the human body through macro anatomy, microanatomy, and evolutionary anatomy [1]. Anatomy education holds significant importance as an integral part of medical studies worldwide. In Iran, anatomy courses, including Gross Anatomy, Histology, and Embryology, are mandatory at the beginning of medical education and form a major component of basic medical science courses [2]. Clinical experts in the field acknowledge that a strong foundation in anatomy is crucial for safe and effective clinical practice. Therefore, adopting a practical and clinical approach to teaching anatomy is necessary to minimize medical errors among students [3]. Moreover, students’ awareness of the significance and clinical applications of anatomy plays a vital role in their skill development. Anatomy is indispensable not only for general medical courses but also for surgical specialties and individuals involved in aggressive treatment and diagnostic procedures [3].

Anatomy training sets itself apart from other basic science courses such as physiology and biochemistry due to its distinct requirements for teaching and learning tools. Various approaches to teaching anatomy involve the use of tools such as cadavers, moulage, human body atlases, training videos, and slides [4].

The use of wax models, or moulages, in anatomy education, has a centuries-long history. Allessandra Giliani, an anatomist in the fourteenth century, played a pivotal role in introducing this artistic and visually captivating approach [5]. Nowadays, moulage involves creating lifelike representations of anatomical structures through realistic simulations and models [6]. Its significance lies in its contribution to anatomy learning, providing realistic representations and fostering hands-on experiences. Moulage also facilitates clinical skills training, promotes problem-solving and critical thinking, encourages teamwork and communication, and aids emotional and psychological preparation [6, 7]. Incorporating moulage into anatomy education helps students develop a comprehensive skill set for their medical careers. Nonetheless, current moulages present several challenges, including the difficulty in clearly representing intricate structures, inaccuracies in production, misalignment with actual organs, and the inability to accurately depict adjacent structures [8].

Together, for the first time in anatomy education courses, we have explored the potential advantages of incorporating larger-sized moulages, megamoulages, in anatomy education, contrasting them with the more common use of smaller-sized models. Megamoulage, a term that combines “moulage” with “mega,” refers to the use of large-scale moulage techniques in anatomy education. It involves creating expansive and immersive moulage simulations that go beyond individual models or structures. Megamoulage offers students a three-dimensional and immersive learning environment, where they can gain a contextual understanding of anatomy. Through the creation of large-scale moulage simulations that depict anatomical structures within realistic settings like clinical scenarios or anatomical landscapes, students develop a deeper comprehension of the interrelationships between structures, vessels, and nerves. This comprehensive learning experience is facilitated by the incorporation of multiple senses, including touch and sight which enhance the realism of educational simulations [9, 10]. Additionally, the collaborative nature of megamoulages allows medical students to work together, fostering effective communication, and teamwork skills. These simulated interactions mirror the dynamics of real healthcare settings, preparing students for future professional interactions in their respective fields.

This study aims to investigate the impact of megamoulages, specifically the brainstem model, on the learning outcomes of 3rd-semester medical students at Gonabad and Kurdistan University of Medical Sciences in Iran. The study will assess how the utilization of megamoulages influences the students’ understanding and retention of the brainstem anatomy. By conducting this research, the study seeks to contribute to the existing knowledge on the effectiveness of megamoulages as an educational tool in the medical field.

Materials and methods

The location of study

The study took place at two institutions, namely Gonabad University of Medical Sciences and Kurdistan University of Medical Sciences in Iran in 2022–2023. Participants were recruited from the pool of 3rd-semester students.

Prior to production of megamoulages

The production of megamoulages involved a sequential process consisting of several distinct stages. From the conception of ideas to the implementation and production of the moulages, the entire duration spanned approximately 20 months. The initial stage of the project involved assessing its feasibility and importance through a needs assessment questionnaire (Table 1) administered to a diverse group of participants (n = 4000), including medical students, residents, faculty surgeons, and anatomists across Iran. This was facilitated through social networks and internal messaging platforms, such as Bale, which allowed participants from various programs to share their opinions. Following the survey, the executive team held consultations with professors from the anatomy department at Gonabad University of Medical Sciences, as well as professors from other universities who taught anatomy courses. Through multiple meetings, they reviewed various teaching tools and methodologies employed in anatomical sciences education.

Table 1 Assessment form for needs evaluation

The production of megamoulages

We created two groups of megamoulages: the first group includes models with no existing counterparts in the market, such as the sectional megamoulage of the brainstem, which displays all structures in both external and internal views with maximum detail, and the inguinal canal megamoulage, which shows the layers of the anterior abdominal wall separately. The second group consists of models that have similar counterparts, but those existing models are of poor quality. In all these models, we ensured that the maximum anatomical points, structures, and neurovascular relationships, as referenced in books and articles, were accurately represented—something lacking in previous models. Approval for the production of these selected models was obtained from the project presenters.

During the production stage of megamoulages, the following steps were undertaken:

1) Design: The external and internal views of the megamoulages were meticulously crafted using 3ds Max and SolidWorks software (USA), with a strong emphasis on detail. The design process for each megamoulage spanned approximately three months. For sectional megamoulages, individual sections were designed and subsequently printed using a 3D FDM (fused deposition modeling) printer from Vafatoos Company in Iran. For instance, the brainstem megamoulage was divided into eight sections, each clearly displaying all relevant anatomical points.

2) Printing: Due to the large size of the megamoulages relative to the available 3D printers in Iran, the pieces were divided and printed separately. The design files were converted to G-code using Cura software (USA), the standard format for 3D printers. For printing, Polylactic acid (PLA) filament, a biodegradable thermoplastic, was utilized. PLA transitions from solid to semi-liquid at 60–70 degrees Celsius, with a full melting temperature of 190–200 degrees Celsius. Each layer was printed at a height of 0.2 mm, with a material deposition speed of 40 mm/s. The 3D printer’s nozzle, through which the melted filament is extruded, has a diameter that affects both detail and speed; a 0.4 mm nozzle was used for this design. Smaller diameters yield more detailed and accurate designs, while larger diameters increase manufacturing speed but reduce precision.

3) Assembly: After printing each piece, specialized adhesives and chloroform were used to connect the sections. Anatomists executed this step to ensure minimal disruptions to the design. The connected parts were then carefully sealed, sanded, and polished to ensure accuracy and maintain the true anatomical appearance.

4) Magnets: To facilitate easy connection and separation of the moulage sections, magnets were inserted into the anatomical sections.

5) Painting: The external surfaces of the printed sections were first painted with acrylic Vesta paint from Ati Mehr Company in Iran, followed by painting all sections. To stabilize the colors and enhance the overall appearance of the megamoulages, a matte varnish from the same brand was applied as a color fixer. Various brushes from Pars-Art (Iran), including flat, liner, fan, round, and filbert brushes, were used throughout the painting process.

Solving probable problems in megamoulages

To improve the quality of the megamoulages, a feedback and improvement process was implemented. The completed moulages were showcased in the department’s dissection hall for two semesters, allowing students, professors, and visitors to provide valuable critiques. During these interactions, feedback was collected to assess the moulages’ strengths, weaknesses, anatomical accuracy, structural integrity, realism, and usability. Constructive criticism and suggestions were shared with the project’s executive group and then analyzed to enhance the design, production, and presentation of the megamoulages.

Learning process evaluation

To evaluate the learning process of 3rd-semester medical students, Kirkpatrick’s model [11,12,13] was employed. The assessment involved two levels: the first level, known as the reaction level, and the second level, referred to as the learning level. At the reaction level, students’ responses were measured using a smile sheet or questionnaire. This sheet aimed to gauge their initial reactions and perceptions of the learning experience. It provided insights into their satisfaction, engagement, and interest in the instructional materials, including megamoulages and current moulages. The questions were on a Kirkpatrick’s scale with very high (5), high (4), medium (3), low options, (2) and I have no idea (1), meaning they were designed to be assigned a rating of 1 to 5.

For the learning level assessment (second level), a scientific test was administered to measure the students’ actual learning outcomes. The students, whose total number was 346, were randomly divided into two groups. One group used megamoulages as their learning resource, while the other group used existing moulages.

Statistical analysis

Statistical analysis was performed by T-Test and the post hoc Tukey using SPSS 22 software (USA). Data are presented as mean ± standard deviation (SD). The significance level was rated at p ˂ 0.05.

Results

Assessment of the need for megamoulages

Based on the data presented in Table 2, the survey results indicate that a significant majority (88%) of the participants expressed the view that incorporating megamoulages in anatomy courses may be beneficial for effective teaching and learning.

Table 2 Medical students’, anatomists’, residents’, and medical faculty surgeons’ viewpoints on Megamoulages based on grade and sex

Figures of some megamoulages

Figures 1 and 2, and 3 represent the megamoulages of the brainstem, mandibular bone, and cerebellum, respectively. In addition, Table 3 shows the diameter of these mentioned megamoulages compared to existing ones.

Fig. 1

The Brainstem Megamoulage. Figure 1 showcases a megamoulage that is composed of eight sections. These sections are likely designed to provide a detailed representation of the anatomical structures associated with the brainstem. The red arrow in the figure indicates the conventional moulage, which may serve as a reference point for comparison or to highlight the differences between the megamoulage and traditional moulage

Fig. 2

The Mandible Bone (Megamoulage). This figure presents a megamoulage specifically focused on the mandible bone. This high-detail anatomical model is designed to provide a comprehensive representation of the mandible. The megamoulage likely includes intricate details of the mandible’s structure, including the body, ramus, condyles, and teeth. By studying this megamoulage, students and healthcare professionals can gain a deeper understanding of the anatomical features and variations of the mandible bone, which is crucial for various dental and maxillofacial procedures, as well as overall craniofacial anatomy

Fig. 3

The Cerebellum (Megamoulage). Figure 3 illustrates a megamoulage dedicated to the cerebellum, a vital structure located at the posterior part of the brain. This anatomical model is designed to provide a detailed representation of the cerebellum's lobes, fissures, and folia, which are the characteristic folds on its surface. The megamoulage likely highlights the intricate network of neurons and connections within the cerebellum, facilitating a comprehensive understanding of its structure and function

Table 3 It indicates the size of produced megamoulages compared to existing ones

The Evaluation of brainstem and cerebellum megamoulages on the learning process of 3rd semester medical students

Table 4 presents the results of the smile sheet-based assessment, which measured the reaction levels of medical students toward the use of megamoulages compared to conventional moulages. The study spanned two consecutive semesters and included students who were randomly assigned to either the control group (taught using conventional moulages) or the intervention group (taught using megamoulages). The findings of the study revealed that the level of student satisfaction with the utilization of megamoulages was remarkably higher in comparison with conventional moulages. This indicates a positive response from the students towards the use of megamoulages as a teaching tool in comparison to traditional moulages. The high satisfaction level suggests that the incorporation of megamoulages contributed to an enhanced learning experience for the students involved in the study.

Table 4 Satisfaction ratings based on smile sheet

Moreover, Table 5 presents the results of an identical written test conducted to assess the performance of anatomy learners in two groups: one group taught with megamoulages and the other group taught with conventional moulages. The average grades of the learners using the made megamoulages were found to be about 2.73 points higher than those of the group taught with conventional moulages.

Table 5 Average scores of students taught with conventional moulages and Megamoulages

Discussion

The course on basic science in medical education holds great importance. It serves as the initial stepping stone towards clinical practice, as a seamless connection between basic sciences and clinical applications is crucial for effective medical education. Within the realm of basic science courses, anatomy holds a fundamental position in medical education, with students typically encountering it during their early years of study. Despite the implementation of changes in the curriculum of anatomy courses across several universities, the predominant methods of teaching anatomy continue to revolve around lectures and hands-on practical training, including cadaver dissection and the utilization of anatomical moulages. The objective of this study was to evaluate the importance of incorporating Megamoulages as a novel approach for teaching anatomy to third-semester medical students at Gonabad and Kurdistan University of Medical Sciences.

The survey results underscore the significant role of megamoulages in medical science, particularly in anatomy education, as highlighted by data from Table 2. The validation process for these models involved multiple levels, starting with the executive team’s development of the plan, position, size, structure, and features of anatomical points based on the latest reference materials. Continuous critique and refinement took place while students were exposed to the moulages during production. Expert review was essential, with anatomy professors assessing the designs and trial samples presented to surgeons, anatomists, residents in general surgery, neurosurgery, orthopedic surgery, urology, obstetrics and gynecology, and medical students at national festivals like the “National Festival of Shahid Motahari Medical Education” and the “Festival of New Technologies in Science Education.” Feedback from these events informed further development, and the minimum viable product (MVP) method was used for additional validation, sending trial samples to renowned anatomy professors nationwide for their approval.

Among general surgery residents, appreciation for the use of megamoulages in learning anatomy was likely correlated with their level of experience in their residency program, although further studies are needed to evaluate this relationship more thoroughly. While residents in other specialties also expressed a positive attitude toward megamoulages, this sentiment appeared to be less pronounced compared to that of surgical residents. In Iran, only women are eligible to pursue residency in obstetrics and gynecology; therefore, there is no available data on the perspectives of male residents in this specialized field. In a cross-sectional questionnaire-based study conducted by Atlasi et al. in 2017, involving 237 Iranian medical students from Kashan University of Medical Sciences, it was observed that students of both sexes displayed interest in learning anatomy through various methods, including using notes, plastic models, pictures and diagrams, clinical context, as well as engaging in cadaver dissection and prosection, while they rarely utilized cross-sectional images and web-based resources in their anatomy learning [14]. Similar to Chinese and Jordanian students, Iranian students also tend to adopt a comprehensive approach when learning anatomy [15, 16]. They prefer gaining a general understanding of an anatomical region as a whole, rather than focusing extensively on cross-sectional images or utilizing web-based resources to study individual anatomical structures. This approach aligns with the principles of Gestalt psychology, which suggests that students benefit from acquiring an overall image of an anatomical region, enabling them to comprehend the interrelationships between different anatomical components [17, 18]. Also, the study conducted by Yammine and Violato in 2014 supports the idea that learning methods incorporating visual components can have a substantial impact on the learning process [19]. In a notable study conducted by Yang et al. (2023), the authors examined the impact of 3D-printed models of four bones—vertebrae, pelvic bone, scapula bone, and sphenoid bone—produced in various sizes (50%, 100%, 200%, 300%, and/or 400% of normal size) on the learning outcomes of undergraduate students without prior anatomical knowledge [20]. Their findings indicated that participants utilizing models with the longest diameter exceeding 10 cm achieved remarkably higher scores compared to those using models measuring less than 10 cm. However, there was an exception for the scapula model, in which performance was equivalent across sizes. Additionally, authors believed that beyond the longest diameter, the presence of inherent features of the bones may facilitate learning [20]. It is important to note that the aforementioned study fundamentally differs from our own in that all participants in our study possessed prior anatomical knowledge, and our models were specifically designed not only with a focus on size but also on anatomical accuracy and aesthetic detail; moreover, a QR (quick-response) code was generated for each megamoulage produced in this project and affixed to the models, enabling students to easily access all related instructional videos by scanning the QR code, thereby reducing their reliance on traditional resources and fostering greater independence in their learning process. Therefore, megamoulages hold the potential to be a valuable resource for anatomy education, leveraging the power of vision to support and enhance the learning process.

In the present study, the majority of full professors in anatomy and medical faculty surgeons emphasized the importance of utilizing megamoulages in anatomy education. However, it is noteworthy that the average percentage of younger professors who shared this perspective was slightly lower than that of their more experienced counterparts. In contemporary times, there are various viewpoints on the connection between age and teaching, as highlighted by Weinkle and colleagues [21]. Nevertheless, as educators accumulate experience, they gain valuable insights that help them recognize and nurture students’ potential while assisting them in understanding their own worth. This may explain why experienced professors place greater importance on the utilization of megamoulages compared to their younger counterparts. The extensive experience and knowledge that seasoned educators possess enable them to appreciate the benefits and significance of incorporating innovative tools like megamoulages into the educational process.

The educational initiative led to the design and production of ten unique megamoulages, including representations of the spinal cord, brainstem, mandible, cerebellum, vessels of the circulus arteriosus cerebri (Circle of Willis), hippocampus, and more. These megamoulages are groundbreaking, being the first of their kind in the country and among the few worldwide. They are entirely original, with no comparable counterparts produced domestically or internationally. For example, the brainstem sectional montage, consisting of eight sections, showcases precise details of nerve pathways, nuclei, adjacencies, and other anatomical features, marking it as the first-ever creation of its kind globally. This study presents figures focusing on the brainstem, mandible bone, and cerebellum as a preliminary investigation. Additional articles will be published in the future, including photographs and findings related to other anatomical structures. Furthermore, this research specifically examines the effects of utilizing brainstem megamoulages on students’ grades, providing insights into the impact of these advanced models on academic performance. It is important to acknowledge that this study is limited to this specific aspect, and further research is needed to explore the broader effects and potential benefits of megamoulages in medical education.

In our study, we also evaluated learning using the first two levels of Kirkpatrick’s evaluation model, which comprises four levels. The first level, reaction, measures participant satisfaction and engagement, while the second level, learning, assesses the increase in knowledge or skills resulting from the educational experience. The third level, behavior, examines the transfer of learning to practical application, and the fourth level, results, measures the broader impact on organizational goals. We found that the satisfaction rate among students who utilized megamoulages in anatomy teaching was significantly higher compared to those using conventional moulages. This level of evaluation was assessed through feedback forms, indicating that the innovative use of megamoulages positively influenced students’ perceptions of their learning experience. Furthermore, at the second level of evaluation, the incorporation of megamoulages in practical classes resulted in a significant enhancement in students’ final grades compared to those who exclusively used conventional moulages. These findings suggest that megamoulages not only improved student satisfaction but also contributed to better academic performance, underscoring their effectiveness in anatomy education. While our study primarily focused on the first two levels, future research could explore how megamoulages influence behavior and results in medical training.

Educators have increasingly focused on student satisfaction, as research indicates that higher satisfaction levels are linked to increased retention, improved academic performance, and overall enjoyment among students [22, 23]. A review study by Stokes-Parish et al. (2018) emphasized the widely accepted belief that moulage plays a crucial role in simulation-based education by enhancing realism and promoting learner engagement [24]. Additionally, a review by Chytas et al. (2020) demonstrated that the use of three-dimensional printing (3DP) in anatomy education leads to favorable outcomes in academic performance compared to 2D images [25]. Specifically, teaching with 3D printed models, such as skulls, resulted in significantly higher post-test scores compared to traditional models [26, 27]. Multiple studies consistently show that 3D printed models are regarded as effective tools for anatomy learning, with over 70% of participants expressing their effectiveness [26, 28]. Furthermore, a study by Swetha and Thenmozhi found that combining innovative technologies, such as visual aids, with traditional teaching methods enhances students’ comprehension of gross anatomy and ultimately improves academic performance [29].

Therefore, we believe that such a teaching method, the use of megamoulages, can likely enhance learning for several reasons. They provide realistic representations that probably boost student engagement and understanding, improve retention of complex anatomical information, and increase accessibility in settings with limited cadaver materials. Megamoulages also likely encourage active learning through model interaction, leading to better academic performance and promoting collaboration among students. Additionally, they probably cater to various learning styles by offering visual, tactile, and kinesthetic experiences. To thoroughly investigate the specific impacts of megamoulages, further studies are needed to examine how they can affect learning outcomes in undergraduate and postgraduate students, as well as in medical students across different semesters.

Conclusions

The integration of megamoulages in medical education, especially in anatomy, is set to enhance training significantly in the next decade. The use of such teaching methods can provide realistic opportunities for students and healthcare professionals to improve their skills. Our study shows strong awareness among students and professors regarding the importance of megamoulages. Evaluated through Kirkpatrick’s model, megamoulages received high scores in the first two levels—reaction and learning—indicating positive responses and knowledge acquisition. Future semesters will assess the higher levels of Kirkpatrick’s model, including the transfer of knowledge to behavior changes (level 3), and impacts on outcomes (level 4). These evaluations will deepen our understanding of the effectiveness of megamoulages in medical education.

Study limitations and future directions

One significant limitation encountered in the creation of integrated megamoulages was the lack of access to suitable 3D printing technology in Iran, which impeded the integration process. Megamoulages represent a considerable advancement in medical education and possess substantial potential for future applications, as these highly detailed anatomical models provide realistic representations of anatomical structures, thereby enhancing both learning experiences and surgical training. As technology continues to progress, the integration of megamoulages with augmented reality (AR) and virtual reality (VR) holds promise for further enriching the educational experience. With improved accessibility and broader adoption, megamoulages could revolutionize medical education by offering comprehensive and immersive learning opportunities for students and healthcare professionals alike. Moreover, the production of strategic megamoulages poses challenges due to their complexity; creating these models is both time-consuming and requires an in-depth study of related texts and articles to ensure that no anatomical detail is overlooked in the design process. Additionally, the design of megamoulages must be entirely innovative, presenting new perspectives on the 3D structure of the body. In this project, considerable time was dedicated to the design phase to ensure that the models achieved maximum precision, creativity, and complexity while accurately resembling human anatomy. Another limitation that affected production speed was the manual coloring of the megamoulages, performed by anatomists to ensure accurate representation and verify the orientation and proximity of anatomical structures. This manual process significantly increased the production time. Accessibility issues in engaging surgeons, anatomists, and residents for surveys further contributed to delays in production. Additionally, errors made during the initial design and production phases necessitated the reproduction of several megamoulages. A further technical limitation involved blockages in the nozzle of the 3D printer, which also hindered production efficiency.

High-fidelity simulation technology stands as one of the most significant advancements in the field of educational simulators, having been utilized extensively in various clinical domains, albeit to a lesser extent in anatomy education. This technology enables the creation of layered models that closely resemble human tissues, each exhibiting distinct densities akin to the layers of the abdominal wall or any multi-layered organ. Furthermore, the advent of artificial intelligence has the potential to innovate teaching methods significantly. It is now feasible to produce AI-based interactive models utilizing large language models (LLMs). If these interactive models are designed as large, articulated structures that clearly display all anatomical features, they could greatly enhance student engagement and enthusiasm for learning. Currently, the development of robots based on LLM technology is underway, indicating a promising direction for future educational tools.