Wax Models Research Articles

Evaluation of the dimensional stability of 3D-printed dental casts

ObjectiveThe objective was to investigate the dimensional stability of different types of 3D printed dental models, and to measure the dimensional changes over time. MethodsFour dental casts with different constructions were printed. The four types of models were as follows: hollow casts with 2.5 mm wall thickness (2,5mm.H), hollow casts with 2 mm wall thickness (2mm.H), hollow casts with 2 mm wall thickness with stabilization bars (2mm.B) and hollow casts with 2 mm wall thickness with gypsum base (2mm.G). The casts were digitized with a laboratory scanner (3Shape E3 Red E Scanner) to obtain the reference Standard Tessellation Language (STL) files. All models were stored at room temperature and scanned again after 1 day and after 1, 2 and 10 weeks. This data was compared to the reference STL file and was analysed by comparing the deformation using surface fitting software (Geomagic Control X, 3D Systems). The results were statistically evaluated using paired Student's t-tests, with the significance level set at p < 0.05. ResultsThere were significant differences in dimensional stability after 10 weeks between the four different dental casts. According to our results, the 2mm.B casts showed the least deformation which was followed by the 2mm.H casts. However, both the 2,5mm.H and the 2mm.G casts showed significant deformation compared to the 2mm.B casts. ConclusionsWithin the limitations of this study – using only one printer and one type of resin – we found that the deformation of all investigated casts remained within the clinically acceptable range. However, there were significant differences between the various construction types printed with the Bego Varseo Printer and Bego Varseo Wax Model Gray material. Clinical significanceIt is crucial to determine how long 3D printed models can maintain their accuracy to prevent potential adverse effects, especially given the extended storage periods required for the time-consuming procedures in prosthodontic and orthodontic treatments.

Antimicrobial efficacy of nanoparticle calcium hydroxide and silver nanoparticles on Enterococcus faecalis: An in vitro study

Abstract Background: In root canal disinfection, intracanal medicaments play a vital role. Typical intracanal medicament, calcium hydroxide (CH), has the lowest efficacy against the biofilm of Enterococcus faecalis. Nanoparticles and their combinations may increase antimicrobial activity, making them better than conventional CH. Aim: The aim is to determine the efficacy of nanoparticle CH (NPCH) and silver nanoparticles (AgNP) against E. faecalis. Materials and Methods: A total of 60 premolars were chosen. The samples were cleaned and decoronated. Cleaning and shaping were done. The apices were tightly sealed with modeling wax before being injected with 5 μl of E. faecalis (ATCC 29212) bacterial suspension, and then left to incubate. Samples were categorized into CH (G-I), NPCH (G-II), AgNP (G-III), and a combination of NPCH + AgNP (G-IV) according to the intracanal medication used. Eppendorf tubes were used to transfer dentin chips after they had been incubated for 7 days. The process of obtaining bacterial colony-forming units (CFUs) involves inoculating sediments onto blood agar. Results: The findings are statistically significant, number of CFUs seen with the Combination of NPCH + AgNP is lower than the other experimental groups, the group treated with CH had the largest number of CFUs. Conclusions: The highest antibacterial effect was seen in combination of NPCH + AgNP.

Zum aktuellen Stand der «raetischen Statuettenwerkstatt»

Robert Fleischer was the first, in 1963, to attribute a common workshop to a group of seven bronze statuettes of the late 2nd/early 3rd centuries AD, the majority of which had been found in the provinces of Raetia and Noricum, more exactly in the area of the Limes forts situated along the Danube (Straubing, Regensburg, Enns) and in their hinterland. What makes these statuettes so distinctive are their stylistic features characterised by a lack of artistic imagination and variation which results in a very schematic modelling of bodies and garments. This uniformity is due to the fact that the wax models were built up by using the same partial negative moulds. Meanwhile the number of bronzes to be attributed to this workshop has increased considerably; today we know of twenty-three statuettes and five single bases. As new types of deities Diana and Vulcan have been added. According to their findspots the statuettes were in demand primarily by civilians living in vici or villas in the densely populated area south of the Limes but there is evidence, too, for their use within military forts.

New research on the Cleveland Apollo

This paper presents new technical details on the original manufacture and modern reconstruction of the Cleveland Apollo, a nearly life-size ancient bronze sculpture of the youthful god acquired by the Cleveland Museum of Art in 2004. Although previous studies had shown the sculpture to be an indirect lost-wax casting, few joins had been discussed in detail. Recent, more comprehensive radiographs, combined with extensive external and internal visual analysis, now permit a more thorough explanation of the assembly, from work on wax models through casting (in at least six sections), patching, and finishing, as well as post-manufacture damage. Together with radiography, analysis of numerous and varied modern restoration materials provides a fuller picture of the way the object was more recently re-assembled. A new digital 3D model of the sculpture, now available, will be essential for future study, interpretation, and display.

Establishing a CAD-CAM workflow for stabilization appliances (Michigan splints).

Stabilization appliances (Michigan splints) are considered well-studied and widely adopted for managing bruxism and temporomandibular disorders (TMDs). Traditionally, these appliances have been fabricated by wax modeling and pressing resin onto casts made from irreversible hydrocolloid or silicone impressions. This article provides a detailed description of an all-digital workflow that uses intraoral scanning and computer-aided design (CAD) software to design a stabilization splint on a digital cast that can be manufactured autonomously by a computer-aided manufacturing (CAM) grinding machine in a subtractive procedure. The workflow is applicable to both dentists and technicians. Special attention is given to aspects and procedures that are important for the successful fabrication of the splint. Working without a cast can save time and money, and the use of CAD-CAM technology provides a homogeneous splint material quality.

Features of using SLA‑technology in the manufacture of molds for lost wax casting

The results of using SLA‑technology in the manufacture of molds for obtaining wax models in lost wax casting are presented. 3D printing modes of molds have been developed to ensure the required roughness of the working surfaces and durability of the resulting molds. The optimal parameters for pressing the wax composition into molds made using SLA technology have been established. It is shown that the use of SLA technology for the manufacture of molds makes it possible to obtain wax models and castings of the required quality. An experimental technology has been developed for the production of castings from bronze by casting according to smelted models.

Evaluating the protective effects of mouthguards with neutralizing agents against chlorinated water-induced enamel erosion.

Dental erosion is a common problem among swimmers. This study evaluated the effects of mouthguard use with or without neutralizing agents, compared to no mouthguard use, on the microhardness of dental enamel after a swimming simulation. Ninety-six human premolars were randomly allocated into six groups of 16 each: Group A (no mouthguard), Group B (mouthguard only), Group C (mouthguard with fluoride toothpaste), Group D (mouthguard with fluoride-free toothpaste), Group E (mouthguard with CPP-ACP), and Group F (mouthguard with arginine-fluoride toothpaste). Enamel slabs were fixed in a wax model (Typodont Articulator) and used to fabricate mouthguards for all groups except Group A. Each specimen underwent cyclic immersion: 2 h in acidic chlorinated water (pH 3.1) followed by 22 h in artificial saliva, for 28 days, to simulate swimming exposure. The change in enamel surface hardness was measured using a Vickers hardness tester. All groups underwent microhardness testing, scanning electron microscopy, and polarized light microscopy. The enamel hardness significantly decreased in all groups after the swimming simulation (paired t-test, P-values < 0.001), except for Group F, which used a mouthguard with arginine-fluoride toothpaste [mean reduction: 17.9 kg/mm2, 95% confidence interval (CI): -1.9, 37.7, P-value = 0.07]. Group A, without a mouthguard, exhibited the highest reduction in enamel surface hardness (mean: 190.6 kg/mm2; 95%CI: 177.4, 203.9), significantly differing from all other groups with mouthguards (P-values < 0.001). However, no statistically significant differences were observed in enamel hardness reduction among the mouthguard groups. SEM micrographs illustrated rough, irregular erosion patterns and several deep porous areas on enamel surfaces of Group A. In contrast, all mouthguard groups showed enamel surfaces similar to sound tooth surfaces. A polarized light microscopic study revealed the deepest dark areas on the enamel surface of Group A. Mouthguards significantly reduced enamel microhardness loss compared to no mouthguard use. While no significant differences were found among mouthguard groups with or without neutralizing agents, those lined with arginine-fluoride toothpaste showed the least enamel loss, suggesting its potential protective effect. Within the limitations of this in vitro study, further clinical trials are needed to validate these results.

Revealing ancient technology: a high-energy X-ray computed tomography examination of a Mesopotamian copper alloy head

Although the origins of lost wax casting extend back into the 5th millennium BCE, it was not until the development of hollow core casting that life-sized metal sculptures could be produced. Based on existing evidence, the earliest adoption of this technique, which involves the inclusion of a clay core within a wax model, occurred in Iraq (Mesopotamia) during the Early Dynastic III period (ca. 2600–2350 BCE). To date, only one hollow core casting from the succeeding Akkadian period (ca. 2350–2150 BCE)—the Sargon Head in the collection of the Iraq Museum—has been studied from a technical point of view. The recent attribution of The Metropolitan Museum of Art's Head of a ruler to this formative period of hollow core lost wax casting provided the impetus for its examination by high-energy X-ray computed tomography—the most practical technique for an object that is continuously on display that could image in 3D the interior morphology of this sculpture given the considerable thickness of its metal walls. This scan revealed a markedly different style of production than the Sargon Head. Although further research on early castings is required to determine the chronological implications of the differences observed and to elucidate more generally the early development of hollow casting technology, the scan of the Head of a ruler provides evidence of some of the challenges encountered and problem-solving strategies used in the casting process.

For special purposes only: Ceramic casting moulds from the late Bronze and Early Iron Age metallurgical workshop in Grzybiany (SW Poland)

AbstractCeramic moulds are regarded as highly specialised, refractory tools used in metallurgy, yet their production process still needs clarification. Our research aimed to characterise the stages of operational chains applied in mould manufacture. The evidence comes from the Late Bronze and Early Iron Age lake settlement in Grzybiany in SW Poland, dated to 9/8th–5th century bce. The site provided rich data on tin‐bronze metallurgy, chiefly the lost‐wax technique, involving hundreds of broken and complete ceramic moulds. Multifaceted petrographic analyses of the sampled objects demonstrated that they were made from locally accessible raw material and processed entirely differently from other ceramics from the site. The paste was tempered with fine‐grained sand and an exceptional amount of organic material, plastic enough to wrap wax models. This proportion of organic temper did not occur in regular kitchenware of this period. The moulds were fired under well‐controlled conditions and relatively high temperatures (700–950°C). Through this sequence of operations, the Grzybiany community obtained high‐quality products designed specifically for metallurgical purposes.

Modeling wax disappearance temperature using robust white-box machine learning

Wax deposition is one of the major operational problems encountered in the upstream petroleum production system. The deposition of this undesirable scale can cause a variety of challenging problems. In order to avoid the latter, numerous parameters associated with the mechanism of wax deposition should be determined precisely. In this study, a new smart correlation was proposed for the accurate prediction of Wax disappearance temperature (WDT) using a robust explicit-based machine learning (ML) approach, namely gene expression programming (GEP). The correlation was developed using comprehensive experimental measurements. The obtained results revealed the promising degree of accuracy of the suggested GEP-based correlations. In this context, the newly-introduced correlations provided excellent statistical metrics (R2 = 0.9647 and AARD = 0.5963 %). Furthermore, performance of the developed correlation outperformed that of many existing approaches for predicting WDT. In addition, the trend analysis performed on the outcomes of the proposed GEP-based correlations divulged their physical validity and consistency. Lastly, the findings of this study provide a promising benefit, as the newly developed correlations can notably improve the adequate estimation of WDT, thus facilitating the simulation of wax deposition-related phenomena. In this context, the proposed correlations can supply the effective management of the production facilities and improvement of project economics since the provided correlation is a simple-to-use decision-making tool for production and chemical engineers engaged in the management of organic deposit-related issues.

Rheology and electrorheological effects of waxy oils with different carbon number distribution

High-voltage electric treatment is an emerging technology for enhancing the cold flowability of crude oil. The primary mechanism involves the accumulation of charged particles (resins and asphaltenes) onto wax particles under the electric field. This electrorheological effect varies with different oil compositions. We have investigated the impact of resins and asphaltenes on the electrorheological behaviors of waxy oils. However, the impact of the carbon number distribution of wax on this effect remains unexplored. Therefore, the objective of this work is to investigate the interaction between waxes with various carbon numbers and charged particles and its impact on the electrorheological behaviors of waxy oils. Model waxy oils containing distinct wax fractions (paraffin and microcrystalline waxes) and varying charged particle concentrations were prepared and studied. The results unveiled that microcrystalline wax model oils exhibited substantial reductions in viscosity and yield stress after electric treatment, up to 80% and 60%, respectively, surpassing the improvements observed in paraffin wax model oils which were less than 50%. This disparity is attributed to the better capacity of resins and asphaltenes to be eutectic with paraffin wax, improving the original flowability of paraffin wax model oil, thus involving fewer charged particles in the interaction with wax under electric treatment, resulting in a weakened electrorheological effect. Resins and asphaltenes struggle to form eutectic mixtures with microcrystalline wax, resulting in minimal flowability improvement of microcrystalline wax model oils by charged particles. Consequently, under the electric field, a substantial proportion of free resins and asphaltenes can interact with microcrystalline wax particles, leading to superior electrorheological effects in microcrystalline wax model oils.

Analysis of the Geometric Accuracy of Wax Models Produced Using PolyJet Molds

The article presents an analysis of the geometric accuracy of wax models produced using PolyJet molds. Photopolymer resin was used to make the molds, and the surface of the model was finished in a gloss mode in the 3D printing process. This allows you to obtain a smooth surface of the molded part model. The geometric accuracy of the models was determined by measurements with the GOM ATOS scanner and analysis of the measurement results in relation to the base model made in the 3D-CAD program. Accuracy analysis was the basis for determining the wear of the mold wear when making subsequent models.

Photochemical transformation of liquid crystal monomers in simulated environmental media: Kinetics, mechanism, toxicity variation and QSAR modeling

Liquid crystal monomers (LCMs) are a new class of emerging pollutants with high octanol-water partition coefficients; however, their transformation behavior and associated risk to environments with high organic matter content has rarely been reported. In this study, we investigated the photodegradation kinetics, mechanism, and toxicity variation of 23 LCMs on leaf wax models (e.g., organic solvents methanol and n-hexane). The order of the photolysis rates of these LCMs were biphenylethyne LCMs > phenylbenzoate LCMs > diphenyl/terphenyl LCMs under simulated sunlight, while the phenylcyclohexane LCMs were resistant to photodegradation. The phenylbenzoate and biphenylethyne LCMs mainly undergo direct photolysis, while the diphenyl/terphenyl LCMs mainly undergo self-sensitized photolysis. The main photolysis pathways are the cleavage of ester bonds for phenylbenzoate LCMs, the addition, oxidation and cleavage of alkynyl groups for biphenylethyne LCMs, and the cleavage/oxidation of chains attached to phenyls and the benzene ring opening for diphenyl/terphenyls LCMs. Most photolysis products remained toxic to aquatic organisms to some degree. Additionally, two quantitative structure-activity relationship models for predicting kobs of LCMs in methanol and n-hexane were developed, and employed to predict kobs of 93 LCMs to fill the kobs data gap in systems mimicking leaf surfaces. These results can be helpful for evaluating the fate and risk of LCMs in environments with high content of organic phase.

Evaluation of the Effect of Various Beverages and Food Materials on the Color Stability of Provisional Materials: An In Vitro Study.

Aim This study aims to evaluate the color stability of four provisional materials: polymethyl methacrylate (DPI®Self-Cure), 10-ethoxylated bisphenol A dimethacrylate (Oratemp® C&B), bis-acryl composite resin (Systemp® C&B, Ivoclar Vivadent), and bis-acryl composite (Systemp® C&B, Ivoclar Vivadent) combined with light-cure composite (Fusion Flo® LC). Materials and methods A total of 40 specimens were meticulously crafted from modeling wax into discs, each precisely 2 mm thick and 20 mm in diameter. Four provisional materials were packed into molds, yielding 10 specimens for each material group. After mixing and polymerization, the specimens were trimmed and polished. Reflectance spectrophotometers were used for initial color assessments based on the CIELAB color space system. Staining solutions, including coffee, Tata Green Tea, Pepsi, and turmeric, were prepared to mimic dietary agents. Artificial saliva, replicating oral conditions, was formulated and sterilized. The specimens were then immersed in various solutions for 15 days at 37 °C. Color measurements were taken on days 2 and 15 using the same spectrophotometer, calculating color differences (ΔE) from changes in L*, a*, and b* values. Results DPISelf-Cure (polymethyl methacrylate)was found to be the most color-stable temporary restorative material, followed by Vivadent (bis-acryl composite resin), Oratemp (10-ethoxylated bisphenol A dimethacrylate), and Fusion Flo (light-cure composite). Fusion Flo exhibited the highest color change by the 15th day. Coffee and green tea demonstrated the greatest potential for causing color changes in the provisional restorative materials. Conclusion DPI Self-Cure exhibited the highest color stability among the provisional materials, with Vivadent and Oratemp following closely behind. Green tea and coffee were the most potent staining agents, while Pepsi and turmeric induced lesser color changes.

Openwork clasp from the Abakumlevo hoard of the 5th Century AD (Vladimir Region): technology and archaeological context

The article considers a round openwork clasp from a hoard of ornaments of the Volga-Finnish women’s attire found in 2021 in the village of Abakumlevo 3 (Suzdal District of Vladimir Region). Currently, the clasp as the entire complex of hoard items is not a typical find on the territory of Suzdal Opolye. The authors conducted a technological analysis of the ornament and made a review of items similar in appearance from the Volga-Finnish sites. The features of the formation of a wax model were studied and the composition of the metal in the clasp was determined. The review of openwork clasps with a similar design and individual ornamental elements showed that the formation of the appearance of the clasp from the Abakumlevo Hoard dates back to the late 4th – early 5th century AD, and all structural elements find analogies, first of all, in the ornamentation of the Ryazan-Oka archaeological culture. Breast clasps recorded to the north and northeast of the main area of the above culture can be considered as markers of the migration directions of the Middle Oka region’s population, actively influencing the surrounding Volga-Finnish population related to the former.

Evaluation of the Effectiveness of Semolina in Improving the Bond Strength of Metal Alloys and Acrylic Resins for the Fabrication of Hybrid Prostheses for Implant Restoration: An In Vitro Study.

Introduction Fixed prosthodontic solutions for restorations of multiple implants are often done using acrylic-metal hybrid prosthesis. These restorations have a high failure rate due to poor bond strength between metal and acrylic, despite using digital attachments and primers. This study has been done to demonstrate an economical yet effective method of increasing shear bond strength between acrylic and metal. Materials and methods Disc specimens of 10 mm diameter and 2 mm thickness were designed using the Meshmixer version 3.5 software (Autodesk Inc., San Rafael, USA). The standard tessellation (STL) file was imported and sent for direct metal laser sintering (DMLS) in cobalt-chromium (CoCr),titanium (Ti), and wax milling. The groups were defined. Ten samples were included in each group. Group 1: Conventional Casting in CoCr; Group 2: Conventional Casting with Opaquer (CoCr); Group 3: DMLS CoCr; Group 4: DMLS CoCr with Opaquer; Group 5: DMLS Ti; Group 6: DMLS Tiwith Opaquer; Group 7: Casting with Semolina (CoCr); and Group 8: Casting with Semolina and Opaquer (CoCr). Wax-up was performed using double wax sheet thickness of modeling wax. Flasking and acrylization were done using the injection moulding technique. A universal testing machine was used for shear bond strength. Results were tabulated and statistical analysis was done usingIBM SPSSStatistics for Windows (IBM Corp., Armonk, USA). The Shapiro-Wilk test was done to confirm the normality of the data, followed by the one-way analysis of variance (ANOVA) test to compare the shear bond strength between metal alloys and heat cure acrylic resin. Results The one-way ANOVA results reveal significant differences in bond strengths among the various groups. Conventional Casting with Opaquer showed no significant difference (p=0.335), but there were notable improvements in bond strength when compared to DMLS CoCr, DMLS CoCr with Opaquer, DMLS Ti, DMLS Ti with Opaquer, Semolina, and Semolina with Opaquer, with DMLS Ti having the largest mean difference (3.368). Conventional Casting with Opaquer significantly outperformed all groups, especially Semolina, which showed the highest mean difference (7.558). Similar trends were seen with DMLS CoCr and DMLS Ti, where Semolina consistently demonstrated superior bond strength. Overall, Semolina produced the highest bond strengths across all conditions. These results underscore the importance of material selection and treatment in enhancing bond strength. Conclusion Semolina can be used as an economicaland reliable method to increase the shear bond strength between acrylic and metal bonding. Its ability to burn out during dewaxing without any remains or remnants in mould deems it a useful material for increasing mechanical bonding.

Comparative evaluation of remaining dentin thickness using single file, two file, and multiple rotary file system - An in vitro CBCT study.

Endodontic success hinges on a multifactorial interplay, with meticulous canal shaping, proper disinfection, and three-dimensional obturation being paramount. Among these factors, the amount of dentin remaining after instrumentation directly influences the biomechanical resilience and longevity of the tooth. This study aims to evaluate the impact of various rotary instrumentation systems, including single-file, two-file, and multiple-file configurations, on the remaining dentin thickness (RDT) following canal preparation. This was an in vitro study, original research article. Sixty mandibular premolar human extracted teeth were decoronated at the cementoenamel junction with a diamond disc. Samples were randomly assigned to three groups using a simple random sampling technique (n = 60). Group I - Single-file system (One Curve, MicroMega) (n = 20), Group II - Two-file systems (2Shape, MicroMega) (n = 20), and Group III - Multiple-file system (Hero Gold, MicroMega) (n = 20). Preoperative cone-beam computed tomography (CBCT) scans were obtained after the sample was mounted on a modeling wax sheet. The biomechanical preparation of canals followed the manufacturer's protocols for every system. Postoperative CBCT scans were obtained. Pre- and postoperative scans were compared at standardized depths (4 mm, 7 mm, and 11 mm) within the canals (coronal, middle, and apical thirds), allowing for a comprehensive assessment of RDT throughout the canal. According to one-way ANOVA, the highest mean was seen in Group I, followed by Group II and Group III. Hence, a statistically significant difference was found between all the groups. Post hoc Tukey's test was done for intergroup comparison. A single-file system preserved more dentin with less aggressive cutting compared to two-file and multiple-file systems.

An in vitro comparative evaluation of efficiency of three rotary nickel-titanium file systems in terms of remaining dentin thickness using cone-beam computed tomography.

The objective of the present research was to assess and compare the residual dentin thickness after biomechanical preparation of teeth using three distinct rotary nickel-titanium (Ni-Ti) file systems. In the current experimental study, a total of 45 single-rooted teeth were selected for the analysis. The cementoenamel junction of each tooth was decoronated using a diamond disc. The teeth were randomly allocated to three groups, with each group representing a different rotary file system: Group 1: Hero GOLD (Micro Mega), Group 2: One Curve (Micro Mega), and Group 3: HyFlex electro-discharge machining (EDM) (Coltene-Whaledent, Altstatten, Switzerland). To evaluate the initial condition of the teeth, cone-beam computed tomography (CBCT) scans were conducted before the biomechanical preparation. The teeth were positioned on a modeling wax sheet, and the CBCT scans provided baseline measurements. The biomechanical preparation of the root canals followed the manufacturer's recommended guidelines for each file system. After the completion of the canal preparation, follow-up CBCT scans were conducted. The postprocedure CBCT scans were then compared with the initial scans to assess any changes in the residual thickness of dentin in the teeth. Post hoc Tukey analysis of variance tests was utilized to examine differences between the groups. A statistically significant result was defined as P = 0.05 or less for every test. The comparison of preinstrumentation and postinstrumentation CBCT images showed that the HyFlex EDM group removed less dentin clinically compared to the other two groups, i.e., Hero GOLD and One Curve. No significant statistical difference was found between Hero GOLD versus One Curve, One Curve versus HyFlex EDM, and Hero GOLD versus HyFlex EDM. Based on the results of this study, the HyFlex EDM file system exhibited superior cutting efficiency at various levels. Nonetheless, additional investigations are required to comprehensively assess the influence of Ni-Ti rotary file systems on the remaining dentin thickness.

To Reenact the Invisible Monster: Demon House and Fury of the Demon

Abstract: This article brings together the television documentary Demon House (dir. Zak Bagans, 2018) and mockumentary Fury of the Demon (dir. Fabien Delage, 2016). In media, demons are invisible monsters, shown primarily by the aftereffects of possession (such as a change in voice or in an abject way like vomiting). They can also be depicted via artistic interpretation. In both films, the filmmakers claim to be providing "evidence" of the titular demons, yet the bases of evidence comprise artworks (paintings, sculptures, wood engravings and wax models), rather than the photographic archive that audiences would expect in "traditional documentaries." Images that do not evince any sort of photographic realism are used as placeholders to retell a completely different event—that may or may not have taken place—to uphold the notion of an invisible monster. The representations are mere copies, a reenactment of a reenactment . These layers of intangibility exemplify both the lack of evidence and the invisibility of the monster.

Frank Cockett and the story of the ancient anatomical wax model of the left iliac vein compression

In 1988, Professor Donini organized an international phlebo-lymphology meeting at the University of Ferrara in Italy. At that time, I was a young surgical resident with the task of picking up Professor Frank Cockett at the railway station. I recognized him immediately, introduced myself and, together, we crossed the station square to my car. I asked him where he wanted to be taken, and he asked me to go to the anatomical museum of the University. We arrived just before the closure time, and Mister Cockett was intrigued and enthusiastic about an anatomical wax specimen.