Nowadays, many museums publish virtual versions of the artifacts they keep in their collections in different 3D model viewers available on the Internet. However, despite the wide experience that some of them have in this field, it is still possible to find many virtual models that do not meet the desirable requirements for their publication on the Internet, especially regarding the optimization of the mesh and color textures needed for greater efficiency in the visualization and downloading of 3D objects. In this study, a sample of virtual models of objects belonging to multiple archaeological museums from different countries is analyzed. We considered multiple characteristics of the models, such as the number of polygons that compose them, the quality of the meshes, filter effects applied during post-processing, etc. The results of this research indicate that it is still necessary to make a greater effort to improve the training and digital skills of the professionals in charge of the digitization process in this area of cultural heritage.

The three-dimensional models of wax belonging to the scientific heritage of the Complutense University of Madrid are a rare and extraordinary material that deserves to be preserved because it has great relevance to understand how surgeons and anatomists found formulas of visual construction that made possible the diffusion of his knowledge about the human body. In the present investigation, an anatomical wax model of the 18th century, with a remarkable degree of structural deterioration and weakness, has been restored, testing a new volumetric loss reconstruction methodology based on photogrammetric digitization of the sculpture, 3D modelling of the lost pieces and 3D printing of their moulds to obtain from them the final copies in waxy material. Due to this methodology, it has been possible to reduce the handling of the figure during the restoration process and the risk of accidental deterioration has been minimized.

Para esta INVESTIGACIÓN se ha empleado una combinación de fotogrametría, modelado digital e impresión 3D como apoyo para la puesta en valor de un modelo anatómico animal, escultura de bulto redondo creada en el siglo XIX, perteneciente al Museo Veterinario Complutense, Universidad Complutense de Madrid (UCM) (España), cuya integridad original estaba comprometida como consecuencia de la amputación completa de su cabeza. La ausencia de fragmentos originales y la inexistencia de fuentes documentales, visuales o escritas que justificasen una anastilosis, llevó a plantear una solución alternativa en la que primara el respeto al original como “ruina”, a la vez que contribuyera a una mejor comprensión de sus valores funcionales perdidos. Gracias a la metodología utilizada, se minimizó la manipulación de la obra y fue innecesaria la aplicación de sustancias químicas durante la fase de registro. El modelo digital elaborado se ha compartido a través de internet, lo que contribuye a su difusión.

The Olavide Museum in Madrid, which was founded in the 19th century, preserves one of the most important collections in the world of three-dimensional dermatological models made of polychrome beeswax. These models have been used for the training of numerous generations of dermatologists in Spain. Unfortunately, many of the figures were preserved in precarious conditions during the time that the museum was closed in the middle of the 20th century, and some could not be found after its reopening. In this paper, we show a method for the recovery of a missing model of which only the original plaster cast remains. For this purpose, we use the combination of a structured light scanner and 3D printing, together with traditional techniques, to reproduce a copy of the original cast, in order to prevent its deterioration during the wax casting. As a result of this study, a highly realistic figure was obtained, which represented, in great detail, the small superficial reliefs of the skin lesions, as well as their colour. The conclusion of this research is that it is possible to recreate, with precision, a didactic model in beeswax from its mould, without the need to use the mould in the process, which avoids any risk of deterioration in the process.

The objective of this work is to present a new practical approach to digital photogrammetry in artistic diagnosis and virtual restoration. The study has been applied to an anatomical model of polychrome wax, dated from the 18th century. In the photographic record, the combination of light sources (visible and ultraviolet) has been used to obtain 3D models that serve as documentation tools to accurately map the state of conservation and to project the virtual restoration. The stages of the photogrammetric process are described along with the lighting strategy and colour management used to solve the problem of virtual registration on surfaces of objects with very bright finishes. The results obtained are promising, because they make it possible to obtain a 3D model with optimal record of the morphology of the sculpture to project virtual solutions within the decision-making model.

Three-dimensional models of anatomy in wax preserved in university museums are rare artifacts of extraordinary technical complexity. In recent years, interest in them has increased among scholars who consider them primary sources of heritage value to approach material culture and the history of science. The fragility of the sculptural material and the inadequate exhibition and storage conditions of many of these collections have caused the formation of pathologies whose conservation treatment is a great challenge for the restorer. In this regard, new 3D digital technologies have created a great impact on the documentation and analysis of interventions in the field of conservation and restoration of cultural heritage. This research aims to demonstrate the technical possibilities offered by 3D digital systems as support tools in curative conservation strategies to mechanically stabilize fragmented sculptural parts. For this case study, we chose an 18th-century obstetric anatomical model made by the Madrid Court sculptor Juan Cháez, and the modeler Luigi Franceschi who belonged to the anatomical cabinet of the Royal College of Surgery of San Carlos in Madrid. In this work, we demonstrate the digitization process carried out employing structured light scanners, digital modeling, and 3D printing. The aim is to create auxiliary structures suitable to support the various original pieces to be adhered while guaranteeing their exact position during the adhesive curing process as well as the volumetric reintegration of faults. In addition tensile and three point bending tests for the mechanical characterization of the selected thermoplastic impression materials are described. Finally, the qualities considered suitable for the most appropriate material for the purpose of the study are detailed. Promising results were obtained since the structures have made it possible to perform fragment adhesions in highly complex areas of the sculpture, ensuring maximum precision, safety, and efficiency during the process.