Plastination is a unique anatomical preservation technique developed by von Hagens et al. (1987) and has been utilized in a broad variety of educational settings. The technique is characterized by replacing water and lipids in the tissues with curable polymers resulting in dry, odorless, and durable preservation. Although widely applied it still seems to be under-appreciated in various educational venues (Azu et al., 2021). Ethical issues have emerged because of commercial applications (Jones, 2002; Jones and Whitaker, 2009). This has been compounded by online presentations where patient identity could potentially be identified. However, current systems are being developed and implemented to ensure the anonymity of online cases using sophisticated digital recognition technologies to de-face MR and CT scans (Schwarz et al., 2021). It is expected that facial de-identification systems will soon be readily available that can be applied to plastinates, rendering them suitable for posting on public platforms.
Photogrammetry provides a novel method to record three-dimensional representations of real-life objects. Multiple photos are composited to provide a resultant 3D surface mesh representing the object. The composited 3D mesh can then be rendered, digitally annotated, and distributed to provide real-time instructional interaction online. However, photogrammetry has limitations when heavily textured or occluded surfaces are encountered, since the visual path of the camera becomes obstructed, leading to data loss in specific regions of the morphological feature. New tracking methods can be used as a computer vision target for recognition of the real-life object, improving surface detection. The data can also be optimized for 3D printing at scale and can serve as a physical model. There is significant educational potential in combining photogrammetry models with segmented and volumetric data from medical scans such as CT and MRI (Nakamatsu et al., 2022). This allows for internal structures to be viewed in the mesh, as well as external surface qualities and diffuse color information (Chang et al., 2016). Combining photogrammetry models with segmented and volumetric data derived from medical scans would provide significant potential, since internal structures can be viewed in the mesh as well as external surface qualities and diffuse color information. This approach also serves to make a record of unique pathological structures that are temporary donations scheduled for cremation.
A previous method involving digitization of plastinated specimens relied on using hand-held scanners to digitize the surface (Tunali et al., 2011). Although this method produced useful models, the scanning procedure relied on expensive technology that is no longer easily available. Additional approaches have used sequential sections of plastinated specimens (Lozanoff et al., 2003; Doll et al., 2004; Sora et al., 2007). These approaches are particularly effective using P40 methodology, however, alignment challenges require significant user input. Cone-Beam Computed Tomography systems (CBCT) and CT methodologies have been utilized to generate data sets and have provided useful output (Chang et al., 2016; da Silva et al., 2020). However, CBCT and CT specimen scanning require recurring financial expenditures. The photogrammetry approach helps to avoid costly investments and can effectively serve the data collection step within the workflow.
A variety of anatomical models and resources should be used including but not limited to cadaver dissections, plastinates, prosections, artistic models, segmentation models, and/or 2D imaging as each model has advantages and disadvantages. One of the advantages of cadaver dissection is the engagement of multiple sensors through palpation. It encourages a better understanding of spatial relationships (Rizzolo and Stewart, 2006; DeHoff et al., 2011). However, the availability of cadavers has been decreasing, and cost and spatial requirements have been issues. The benefits of online models are that students can access the models anywhere and models can be kept. Palpation is not available, and students are unable to practice dissection are some of the disadvantages of using online models. This evidence indicates that using a variety of models will increase the comprehension and understanding of anatomy.
The value of cadaver dissection in learning anatomy has been discussed (Flack and Nicholson, 2018; McMenamin et al., 2018). The study by Mathiowetz et al. (2016) reported that the group that used gross anatomy laboratory had a significantly higher grade percentage, self-perceived learning, and satisfaction, than the group that used online anatomy software. On the other hand, online and remote learning methods are perceived by students as highly convenient for the study and analysis of anatomical structures (O’Byrne et al., 2008; Kuyatt and Baker, 2014). Interactive online resources can be useful for deep understand of anatomy. Rather than choosing between gross anatomy dissection and online models, using multiple technologies should enhance existing teaching practices rather than replace them.
Our experience during the COVID-19 pandemic allowed us to test the value of dissection and online streaming dissection using a variety of models by comparing student’s preferences. During instances where physical interaction is limited, such as the COVID-19 pandemic, remote access to virtual models encourages collaboration and discussion at a safe distance. A variety of virtual platforms allow for collaboration and visualization of structures on numerous electronic devices (Hong et al., 2015). Rad3D is a Digital Imaging and Communications in Medicine (DICOM) viewer that can be accessed on any mobile device. Sketchfab is also a virtual platform that is emerging as a hub for sharing 3D models. Online platforms allow for more accessibility to information by a broader range of audiences. The potential acquisition of a Creative Commons license can provide free non-commercial access and also provides an outlet that is easily available to users. The application of XR augmented technology can also be applied as a non-destructive means to utilize museum specimens, creating large samples for conveying unique and novel anatomical information (Nisiotis et al., 2019; Sugiura et al., 2020; Mikami et al., 2022). This provides a unique opportunity for collaborative research and examination of potentially large collections of anatomical plastinates. Future work will be directed at creating freely available, online anatomical libraries based on plastinated specimens.
Museum specimens are particularly attractive for 3D imaging and various workflows have been described to generate 3D models previously (Chhem et al., 2006; Jutras 2010; Tomaka et al., 2009; Jocks et al., 2015). Museum specimens are of interest due to their age, historical relevance, and uniqueness (Marreez et al., 2010), while also posing obstacles since they are fragile and accessible only to individuals who gain access to their locale. Plastinates are being used more frequently in museum displays, and online presentations would permit the complete visualization of structures from various perspectives and depths, as well as enable access to the structure by a broad range of audiences. Future work will be directed at applying this workflow to old and rare museum specimens for online display.
As a whole, online learning is perceived by students as highly convenient for the study and analysis of anatomical structures. A variety of virtual models including dissection and plastinated models, artistic models, and CT/MRI segmented models allow for collaboration and visualization of structures. The plastinated models enrich the students’ anatomy learning experiences by enabling viewing from all angles and allowing accurate spatial relationships of structures. Plastinated models also show true anatomical variation, disease, and anomalies which might have helped students in the clinical application aspect. Future work will be directed at creating freely available, online anatomical libraries and expanding the context and interactivity, including case studies and VR for the immersive experience of the 3D structures.
Acknowledgments
We would like to thank Professor Brittany Biggs (Academy of Creative Media, University of Hawaii at Manoa) and media interns, Sylvia Lee, Ross Turner, Troy Macris, and Isaiah Sanchez for assistance in model development and editing.
The authors sincerely thank those who donated their bodies to science so that this research could be performed. These donors and their families deserve our highest gratitude.
Because the initial embalming did not contain formaldehyde (it was first reported in 1859 by Butlerov, and not commercially available until late 19th – early 20th century), and the body was not under regular control for 45 years, the fungus had probably already formed during the disease in N.I. Pirogov’s lifetime. It is therefore probable that the body had been colonized externally and internally by the fungus Penicillium citrinum before, and at the time of, death. Subsequent gradual growth continued due to the humid, non-sterile environment of the sarcophagus and the tomb.
Penicillium citrinum is a fungus with minimal pathogenicity. It is a classic reducing organism that breaks down tissues and biological materials of plant and animal origin. It is a ubiquitous organism that occurs everywhere. Pirogov was probably in the terminal stage of oral cancer, and hence, a patient with seriously weakened immunity. It cannot be ruled out that he may have already had this fungus in him, for example in the respiratory and digestive tracts. Fragments of hyphae or spores of this fungus could have been introduced deep into the internal organs or bones in a hematogenous manner. Before his body was subjected to the embalming process and soaked in the appropriate solution, these fragments and spores could germinate in the deceased's body and grow and survive for some time. Monitoring the possible occurrence of microbial contamination of the body is important for long-term preservation of the body in good condition (Karrar Alsharif et al., 2017). Tissues preserved with formaldehyde solutions generally show no, or minimal, microbial contamination (Balta et al., 2019).
Based on the results reported here it would be suitable to perform colorimetric measurements at points of interest (forehead, temples, earlobes, cheeks, lower jaw, and chin) during, and for some time after, a planned body embalming, and then compare the results. Colorimetry can also be used to compare skin color changes when using different methods of body preservation or embalming. Changes in skin color indicate ongoing degradation processes, and colorimetry allows for such processes to be detected early before they become visually apparent. The results show that any readily-available compact hand-held device, of which there are a large number on the market, can be used to register the color of the skin.
The complexity of 3D scanning is comparable for both the Space Spider and EinScan Pro+ scanners. However, with the second scanner it was sometimes more problematic to overlap the scan sets with each other, and during scanning it was necessary to move the scanner very smoothly. Scanning with the Leo scanner was easier, thanks to the absence of a physical connection to a PC, and the ability to monitor the scanning process directly on the scanner display. The Leo scanner could be further away from the scanned object, which can be an advantage, but also a disadvantage, for example in a limited space. Profilometry can also be used for surface registration (Astahov, 2000).
For long-term preservation of bodies, it is also necessary to create constant storage conditions, i.e., by preventing microbial contamination of the body, ensuring a constant temperature and relative humidity, maintaining a protective atmosphere in the sarcophagus/coffin, and preventing UV radiation.
Plastination has benefits in comparison to wet specimens (either formalin- or glycerin-fixed) since this preservation technique provides more durable, odorless, tactile, and non-toxic specimens. In addition, when completely plastinated with silicone, specimens do not drain indefinitely, and there are no reports in the literature of color changes over time (von Hagens et al., 1987). Pádua et al. (2016) proposed the chemical reversal of glycerin as a step prior to plastination, as follows: the glycerin-impregnated specimen was immersed in 50% alcohol for seven days, washed for 24 hours in running water, immersed in potassium hydroxide solution 1.5% for eight hours, washed in running water for 48 hours, and immersed in 70% alcoholic solution for another 72 hours. After these steps, the specimens go on to dehydration. In the research reported here, we sought to verify if it is possible to efficiently remove glycerin from specimens using only acetone.
The acetonometer is an analytical instrument that measures the concentration of acetone through its density. Thus, considering that the density of acetone (0.784 g / cm³) is different from that of water (0.997 g / cm³) and glycerin (1.26 g / cm³) (Solomons and Fruhle, 2001), the acetonometer was a suitable instrument to monitor the removal of glycerin and residual water from biological tissues used in this work.
Although the conservation principle of the glycerin-fixation technique is dehydration, glycerin is not a volatile solvent and, therefore, the specimens were subjected to dehydration in acetone. Therefore, the acetone served as an intermediate solvent to be replaced by silicone. During dehydration, the exchange of substances between biological tissues and the solvent (acetone) occurs by simple diffusion. The choice of a greater volume and the number of replacements of acetone baths was made to guarantee a more efficient removal of glycerol from the specimens, since we did not know its behavior when exposed to acetone. The substitution of glycerin by acetone was evidenced by the change in transparency of the acetone bath. The more glycerin diffused into the acetone, the milkier it became. After the last acetone bath, the milky aspect was no longer perceived, probably due to a complete, or almost complete, removal of glycerin. The use of hydrated acetone may have helped in the removal of glycerin, since the solubility of glycerin in water is greater than in alcohol and acetone.
It is known that the glycerin-fixation process causes a certain amount of tissue shrinkage, which is mainly caused by the dehydration promoted by alcohol at room temperature (Brown et al., 2002). The impregnation rate is an important factor in the degree of tissue shrinkage, as even at room temperature (20 °C), the S10 silicone viscosity remains substantially higher (460 mPa.s) than acetone viscosity (0.33 mPa. s), which determines some level of tissue retraction. Therefore, we adopted a slower pace of vacuum progression (1 bubble/second/observed area), allowing the acetone to be extracted from the specimens slowly, permitting a more efficient substitution of the acetone by the silicone, and thus avoiding greater shrinkage during impregnation (Monteiro et al., 2018).
One of the advantages of using plastinated specimens versus the glycerin-fixed specimens is that plastinated specimens are dry in comparison to the constant wet feeling of the glycerin-fixed specimens, with the latter requiring the use of gloves during handling of the specimens.
In the qualitative macroscopic analysis of the specimens regarding color, volume, and texture aspects, the results obtained in this study were extremely satisfactory, since the parameters analyzed did not show significant changes. The impregnation and curing phases of the plastination process appear to have proceeded normally in previously glycerin-fixed specimens. These results are different from a few authors, who mentioned that all embalming fluids containing long chain alcohols (e.g., glycerol) have to be removed before dehydration (Fasel, 1988; Ravi and Bhat, 2011; Sora, 2016;), and Padua et al. (2016), who described several chemicals (including ethanol) to remove the glycerin from glycerin-fixed specimens before plastination. Although the solubility of glycerin is greater in ethanol than in acetone (Clasen et al., 2015; Marçal, 2015), the results of this research demonstrate that it is possible to plastinate specimens without a pre-treatment to remove glycerin. Acetone is also an organic solvent soluble in water and glycerin, permitting the removal of these substances efficiently without the need for other chemicals. The technique proposed by our study saved time and eliminated the cost of other chemical reagents, which are not necessary using the protocol described here.
In order to investigate a method of plastination for glycerin-fixed specimens, plastination at room temperature was chosen, because higher temperatures facilitate the replacement of glycerin by acetone in dehydration, and acetone by silicone in forced impregnation, when compared to the cold temperature method. This is directly related to the substances' viscosities, since at room temperature the viscosities are lower and, thus, the fluid replacement dynamics are easier, faster, and more efficient. At negative temperatures, glycerin becomes more viscous, which can affect its replacement by acetone. In this sense, according to chemistry, in general, the miscibility of substances tends to decrease at lower temperatures. In addition, impregnation at room temperature causes less tissue shrinkage, considering that the specimen has already suffered a certain degree of shrinkage in the glycerin method.
Some limitations of the method should be mentioned: (1) given the miscibility of glycerin in acetone, the use of larger volumes and quantities of acetone baths is suggested for more efficient removal of glycerin; (2) the proposed plastination method has been tested only at room temperature; (3) the acetone used in dehydrations must be recycled/distilled after use to avoid contamination of other specimens.
Plastination allows preservation of previously fixed, three-dimensional organs and, in this case, the heart of a rare Southern resident killer whale. The result is a specimen that preserves both the external and internal morphology.
Studies on marine mammal hearts are commonly based upon formalin-preserved, wet specimens. However, published descriptions of hearts preserved through plastination techniques are also available for relatively few species. These include the ringed seal (Phoca hispida) (Henry et al., 2005; Smodlaka et al., 2008), the bottlenose dolphin (Tursiops truncatus) (Contreras et al., 2015) and the blue whale (Balaenoptera musculus) (Miller et al., 2017). In some of these studies vascular color injection of the coronary arteries was used (Tarpley et al., 1997).
External Morphology
Regarding the external morphology of the heart of the killer whale, its flattened appearance was conspicuous, and has also been described in other marine mammals, such as the harbor porpoise (Rowlatt and Gaskin, 1975), minke whale (Ochrymowych and Lambertsen, 1984), beluga whale (Bisaillon et al., 1987), harp seal (Bisaillon, 1982), ringed seal (Smodlaka et al., 2008), bowhead whale (Tarpley et al., 1997), pygmy killer whale (Klomkleaw et al., 2005) and gray, sei and sperm whales (Truex et al., 1961). The two interventricular sulci, paraconal and subsinuosal, were well differentiated, as described in the minke whale (Rowlatt, 1981), the beluga (Bisaillon et al., 1987), and the pygmy killer whale (Klomkleaw et al., 2005). Paraconal and subsinuosal interventricular sulci appeared almost halfway between the cranial and caudal borders of the heart, and coursed directly to the apex (Klomkleaw et al., 2005).
The size of both coronary arteries was similar in the plastinated heart, and they had marked sinuosity (‘tortuosity’ of Rowlatt, 1981 and Truex et al., 1961) and similar contribution to myocardial vascularization. Similar morphology has been previously described in marine mammals, including the minke whale (Ochrymowych and Lambertsen, 1984), beluga whale (Bisaillon et al., 1988), bowhead whale (Tarpley et al., 1997), toothed whale (Rowlatt, 1981), and the pygmy killer whale (Klomkleaw et al., 2005), as well as sei and sperm whales (Truex et al., 1961). A contrasting condition of left or right coronary artery dominance was noted in the gray whale (left coronary artery) and in two of five sperm whales (right coronary artery) by Truex et al. (1961). However, equal size and distribution of both left and right coronary arteries was noted by Rowlatt (1981) for toothed whales and three of the five sperm whales investigated by Truex et al. (1961) Results observed in the pygmy killer whale coincide with the distribution described in this work, although Klomkleaw et al. (2005) mentioned a circumflex branch from the right coronary artery, a descriptive not recognized in the Nomina Anatomica Veterinaria. A circumflex branch was also described by Rowlatt (1981) for both minke and toothed whales. Anastomotic coronary arteries have been identified in a variety of cetacean species by several authors (Race et al., 1959; Truex et al., 1961; Ochrymowych and Lambertsen, 1984; Bisaillon et al., 1988; Tarpley et al., 1997), although none were identified in the present study.
Few reports of CT scans (Smodlaka et al., 2008; Ivančić et al., 2014) or MRI (Tarpley et al., 1997) for anatomic description of marine mammal hearts were found. No published reports of the use of endoscopy for examination of the lumen of the atria or ventricles in whales were located.
CT Study
The CT scan images facilitated study of the internal conformation of the killer whale heart. This approach has shown the distinctiveness of the ventricular walls, especially the relatively thin right ventricular wall, and reduction of the interventricular septum surface. This last has been related with the flattened heart shape and the thicker wall of the left ventricle (Rowlatt, 1981). A spacious right ventricle has been described in the harp seal (Bisaillon, 1982) and, with CT images, in the ringed seal (Smodlaka et al., 2008). Truex et al. (1961) noted ‘surprising’ thinning in the anterior and lateral ventricular walls, as well as the apex. Other authors described observing right ventricular hypertrophy in the minke whale heart, proposing that this condition could be related to hemodynamic changes associated with apneic diving and the accommodation of associated preload (Halina and Gaskin, 1978; Ochrymowych and Lambertsen, 1984).
The CT images of the plastinated killer whale heart showed that the apex was formed not only from the left ventricle, but also from the right ventricle, as has been described in the beluga whale (Bisaillon et al., 1987), harp seal (Bisaillon 1982), ringed seal (Smodlaka et al., 2008), sperm whale (Truex et al., 1961) and blue whale (Miller et al., 2017).
Endoscopy Study
Endoscopic exploration also facilitated detailed study of the valves in the plastinated killer whale heart. Previous references to the atrioventricular valves have been published in other marine mammals, such as the minke whale (Ochrymowych and Lambertsen, 1984). In ringed seals, the left atrioventricular valve resembles an interrupted circular valve without divisions into parietal and septal cusps (Smodlaka et al., 2008). However, we could readily identify each cusp of the atrioventricular valves. Moreover, the endoscopy study supplied a broad collection of detailed images of the inner anatomy of the atria and ventricles.
The occasion to plastinate a killer whale heart affords a unique opportunity to further inform the public and researchers about the adaptive variation in the cetacean heart, as well as offering novel educational moments. The plastinated and dissected SRKW heart was displayed during the Royal Ontario Museum’s 2017 exhibition ‘Out of the Depths, The Blue Whale Story’ and will be a focal asset in upcoming natural history exhibitions. The killer whale heart is one of a series of plastinated specimens used to inform and teach visitors about the unique character of the cetacean heart, as compared to the hearts of typical land mammals. This series includes the largest preserved vertebrate coronary specimen of a blue whale heart (Miller et al., 2017). The quality of anatomical detail has been excellent, amenable to both endoscopy and CT explorations. Overall, the project yielded insights into the complexities of large, hollow organ plastination, and the transfer of such a unique specimen across international borders during the various stages of its preparation. Like the preservation by plastination of a severely autolytic blue whale heart, the information derived from the SRKW project continues to improve the potential for conserving rare anatomical material in the future.
Traditional embalming solutions used for specimens intended for plastination usually include formalin at 5-15% (Henry et al., 2019), however, higher concentrations of 10-20% should be used for brains (Henry et al., 1997). Based on the constituent concentrations shown in Table 1, the RVC’s embalming solution formalin concentration ranges between 7.5% - 15%. Whichever concentration of formalin chosen, there are differing opinions on whether the addition of further chemicals to the embalming solution is beneficial or disruptive to the plastination process. Some believe embalming solutions containing alcohols, glycerin, glycols and/or phenol should not be used on specimens destined for plastination (DeJong and Henry, 2007). Others, however, have used solutions containing one or more of these chemicals and are satisfied with the results (Cook and Dawson, 1996; Pretorius, 1996; Norman and Nicoll, 2017).
Some authors have gone down the route of having two separate embalming solutions, one for dissection specimens, and one specifically for specimens intended for plastination (Cook and Dawson, 1996). This would not be a suitable option for the RVC, as the majority of the specimens plastinated are those which are initially either used as student dissection specimens during undergraduate teaching, or as prosections produced by staff for demonstration. Therefore, the embalming chemicals selected by the RVC are primarily chosen to provide teaching specimens which are not only long lasting and easy to store, but also provide good color and tissue differentiation during dissection. Good quality student dissection or prosection specimens may then be retained once finished with, for plastination. Only a very small number of RVC specimens are ever embalmed with plastination being the primary goal.
Most embalming solutions are traditionally transparent, which, when used in conjunction with the standard embalming process of draining blood from the cadaver, can produce a very pale grey/beige-looking specimen. This is not ideal, as good tissue differentiation is key in aiding student identification and understanding of anatomical structures. In the past, various embalming solutions were developed to aid the preservation of color e.g., Kaiserling’s, Klotz, Jores’, and McCormick’s solutions, and other coloring chemicals, such as eosin and merthiolate (Iliff et al., 2019). However, these seemed to yield mixed results. Plastination can further bleach the color from specimens during the dehydration stage (McCreary et al., 2013) leaving specimens pale, with features harder to distinguish. Today, in order to achieve a more natural and useful appearance, many plastinated specimens are painted or stained (Raoof et al., 2013; Mccreary et al., 2013; Yu et al., 2014; Kang et al., 2015). A stain could be added to the acetone bath, or a pigmented silicone could be used during the impregnation stage of plastination. These options are unfortunately not selective, so all the tissues will be the same color (Iliff et al., 2019), which would not be an improvement. The ideal would be to have an embalming solution which produces good tissue color differentiation upon dissection, which is also suitable for plastination.
This study has looked at the production of plastinated specimens using a colored embalming solution, however the number of specimens used was limited and further investigations should be made into its wider suitability.
Re fipnedu gicwi piv wan afmab ora cappof utdel repuej jolgowo fuwab fazle panlu cut ge diva. Ugosivbel gibak vez cuvo tepipidah fej hi vuz tog kiduzbar wadpihwu lali maibzi olijuzir. Sar eluziv siktaso aceido rohiz go jomoz tot midjog bezpo hetfeku vawha weko edutobisi vehbanoj. Uwozo ocabiile uzunodik an vofen meleb nuzolfa to ciabvi hi zeklaoha fehhuniv. Mimver tofhaw zusdohef te erlug furmoeb safcow lu moejadev bo rum edgi geticpac. Jiuje gigarmo gueki zi nobeb huug
Plastination, which employs polymers to preserve
biological specimens, is recognized as ‘the greatest
progress of morphology preservation technology in the
20th century’ (Latorre et al., 2003). The commercial
production of plastinates of whole bodies, slices, and
animations from plastinates and organs for use in
anatomical education are readily available and being
produced in various centers across the world where the
technology and expertise abound (Azu et al., 2012).
While there is paucity of literature evaluating students’
opinion on plastinated specimens and its efficacy as an
adjunct to the repertoire of anatomical teaching and
learning aids, there are some reports of positive
feedback from use of plastinates by Latorre et al.,
(2007), Dawson et al., (1990) and Purinton (1991),
especially in the developed countries of USA and
Europe. However, within the African context, and South
Africa in particular, plastination and plastinated
specimen use remains poor, perhaps owing to low
technological know-how. Many respondents in this report
were aware of the various anatomical resources and
teaching aids in their learning of anatomy, with cadavers
(95.0%), and plastic models (59.8%) being the most
widely used. Noticeably, plastinated specimens were
less used by the respondents in this study. This shows
that the exposure to plastinated specimens in the
learning of anatomy at UKZN is still very low, which
contrasts with the results of Kamier (2012) where most
undergraduates (66.4%) indicated predominant use of
plastinated materials, prosected specimens, and models,
to augment their learning of anatomy. The minority
(33.6%) agreed that the study of anatomy through the
dissection of cadavers was the best method of learning
anatomy.
Beliefs and religion influence opinions about plastinated
specimens and the use of human bodies in learning
anatomy. Religious considerations also make it difficult
to obtain teaching specimens (Cannas and Fuda, 1991)
and enhancing the bequeathal/body donor program.
Whilst we did not examine the influence of religion as a
factor towards understanding (and/or wanting to learn
about plastination and plastinated specimens) by the
respondents, literature indicates the strong influence of
religion on an individual and how treatment of the dead
is handled (whether Islamic, Hindu, Christian, Jewish or
Orthodox) (Aramesh, 2009). Though our report shows a
high preponderance of Christianity as a religion by most
of the respondents, this did not reflect positively in the
number who wanted to learn about plastination. There
were 54% Christian respondents in the study, but only
12% indicated interest to learn about plastination. We
would have expected the latter to be more.
In this study, the respondents declared that they had
been exposed primarily to the use of cadavers,
prosected specimens and plastic models, which could
have contributed to their low awareness of plastinated
specimens and plastination. A study by Oyeyipo and
Falana (2012) showed that most of the students used
cadavers for their study of anatomy (in South-western
Nigerian Medical School) and indicated that dissection
enhanced their thinking ability. However, this was
different from the report of Fruhstorfer et al. (2011)
where students (Warwick Medical School, UK)
exclusively used plastinated specimens for all regions of
the human body, supplemented by non-cadaveric
material. Students who no longer have any exposure to
wet cadaveric prosections nor the opportunity to
participate in cadaveric dissections thus,
understandably, think plastinated specimens alone are
good. These opposing views and feedback characterize
a paradigm shift in the introduction of plastinates into
anatomy departments, and could help to inform teachers
on how to model the right approach in educating
students to use this additional resource. It is interesting
to note that the majority of the respondents in this study
were females (75%) and a recent report by van der
Merwe et al., (2016) shows that over 62% of admissions
into the medical schools in South Africa are females,
corroborating our report.
The low level of awareness on plastinated specimen
usage, particularly as it relates to suitability for teaching
purposes as well as its handleability, further highlights
part of the challenges faced by experts and users of
plastinates. While it enhances visualization of structures,
it does not allow for their manipulation, and thus
structures such as ligaments and muscles are rendered
rigid or semi-rigid (Valdecasas, 2009). Despite this
deficiency, the positive aspects and characteristics of
plastinates (espoused by Latorre et al., 2007) as a useful
teaching tool remains very stimulating and thus can be
explored in the local context.
In our study, only 32.98% of the students wanted to
learn more about the process of plastination, while 71%
did not. This unusual response could be attributed to the
fact that many students were not aware of plastination in
10 – Azu, et al
the first place and therefore had no prior knowledge or
entertained serious misconceptions regarding the
process. This response was different from a study done
by Azu et al. (2012) (carried out with medical students at
the University of Uyo-Akwa Ibom State, Nigeria), where
over 94% of the students wanted to learn about the
technique. Recently, there has also been some doubt
amongst scholars in anatomical education about the
necessity of using cadaveric material for undergraduate
anatomy education (Fruhstorfer et al., 2011). It is argued
that not allowing students proper exposure to other
methods limits their learning of anatomy. In other words,
having limited or no plastinated specimens or other
teaching aids, disadvantages students.
As previously mentioned, the fact that most students did
not have any experience with plastinated specimens
means that they were, therefore, not in a position to
judge the value of plastinated specimens. This opens a
gap that could be utilized in the introduction of
plastinated materials, due to its characteristic nature that
favors dry, odorless and tactile nature of specimens. The
examination of cadaveric specimens appears to be a
crucial element for anatomical studies, and it is therefore
questionable to substitute cadaveric learning entirely for
contemporary modalities (Fruhstorfer et al., 2011). In this
study, the respondents were comfortable with wet
cadavers, since this was the only method used in their
learning of anatomy and in exams. The respondents
graded wet specimens more favorably and suitable for
practical examination than plastinated specimens which
were graded very low (23.37%).
More than half (57.45%) of the respondents in our study
believed that plastinated specimens cannot replace the
cadaver and the reason may relate to very low
awareness of plastination amongst those sampled, and
the fact that they are more exposed to the traditional
embalmed cadavers. Plastinated specimens are more
often used in the developed countries of Europe and
America than in the developing countries of Africa, as
illustrated in a study by Fruhstorfer et al. (2011). Their
results showed that students highly appreciate
plastinated specimens because they were clear and
odorless. We previously reported that the advocacy of
tissue preservation by plastination has been gradual in
developed countries (Azu et al., 2012). The high-cost
implications of setting up a plastination laboratory and
the necessary technical and human capacity may be
responsible for the slow pace of deployment; most
developing countries still battle with basic requirements
for medical training, with the implication that balancing
efficient and effective delivery of anatomy curricula using
additional repertoire without compromise on quality will
be needed. We believe that the College of Health
Sciences at the University of KwaZulu-Natal is yet to
benefit from this resource and needs to harness all
efforts to aid the learning of anatomy with additional
tools like plastinated specimens.
While this study does not champion the complete
replacement of cadavers in the training of future medical
students, it can point the way forward in resolving the
problem of cadaver shortages. Technological
developments such as this one are having immense
repercussions for clinical anatomy (just as other
developments have transformed cell and molecular
biology). At the present time, plastinated products not
only serve as a training tool, but also as a research tool,
and its use is increasing throughout medical schools
(Pashaei, 2010).
We expect positive improvements in future anatomy
pass rates (seen by students as a difficult subject) with
the introduction of plastinates. Another positive outcome
of the project is that other clinical departments (like
surgery, radiology etc.) in the medical school are
expected to benefit from the use of plastinated
specimens, which could add to their research
capabilities.
A limitation in this study is that it is a descriptive study,
which compares teaching and learning aids in the study
of anatomy and assesses participants’ subjective opinion
regarding the various characteristic of the different aids
for teaching and learning anatomy. It is also difficult to
extrapolate our findings to a larger student cohort in view
of the limited number sampled, and hence, future studies
should incorporate this factor.
