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BACKGROUND: Tissue engineering represents a promising field in regenerative medicine, with bioresorbable polymers such as polycaprolactone (PCL) playing a crucial role as scaffolds. These scaffolds support the growth and repair of tissues by mimicking the extracellular matrix. OBJECTIVE: This study aimed to assess the in vivo performance of three-dimensional PCL scaffolds by evaluating their effects on bone repair in rat calvaria and the tissue reaction in subcutaneous implant sites, as well as their impact on major organs such as the kidneys, lungs, and liver. METHODS: Three-dimensional scaffolds made of PCL were implanted in the subcutaneous tissue of rats' backs and calvaria. Histological analyses were conducted to observe the bone repair process in calvaria and the tissue response in subcutaneous implant sites. Additionally, the kidneys, lungs, and livers of the animals were examined for any adverse tissue alterations. RESULTS: The histological analysis of the bone repair in calvaria revealed newly formed bone growing towards the center of the defects. In subcutaneous tissues, a thin fibrous capsule with collagenous fibers enveloping the implant was observed in all animals, indicating a positive tissue response. Importantly, no harmful alterations or signs of inflammation, hyperplasia, metaplasia, dysplasia, or hemorrhage were detected in the kidneys, lungs, and liver. CONCLUSIONS: The findings demonstrate that PCL scaffolds produced through additive manufacturing are biocompatible, non-cytotoxic, and bioresorbable, promoting osteoconduction without adverse effects on major organs. Hence, PCL is confirmed as a suitable biomaterial for further studies in tissue engineering and regenerative medicine.

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A reconstrução facial forense corresponde à construção facial de um indivíduo, realizada a partir de um crânio não identificado. Pode ser bidimensional ou tridimensional, realizada de forma manual ou digital. Neste último caso, o advento das novas tecnologias da informação em muito contribuiu, sobretudo no que diz respeito ao desenvolvimento de programas de imagem 3D, equipamentos de tomografia computadorizada e scanner 3D. Diferentes técnicas, equipamentos e softwares têm sido empregados com esta finalidade. A caracterização de reconstruções faciais com pelos como cabelo, cílios e sobrancelhas, tem sido questionada, sobretudo quando não há informação sobre tais dados. Este trabalho analisa reconstruções faciais forenses digitais 3D e, com base em evidências, propõe um protocolo piloto para a execução e apresentação das mesmas. Reconstruções faciais digitais, confeccionadas com o software 3ds Max, sem caracterização de pelos foram confeccionadas, utilizando três diferentes tabelas de espessura de tecidos moles, e submetidas a um teste de reconhecimento, por 22 examinadores. Em todos os casos, o sujeito-alvo foi o mais reconhecido, chegando a ser reconhecido por 45,45% dos avaliadores. É apresentada uma proposta de protocolo piloto para a confecção e apresentação de reconstruções faciais forenses. Para a confecção das mesmas, é empregado o software 3ds Max, e recomendado o emprego do software ZBrush para a pós-produção (como aposição de rugas e linhas). É impresso um protótipo da reconstrução facial, que pode facilitar o reconhecimento. Os autores afirmam que não deve ser realizada a caracterização com pelos, o que pode prejudicar o reconhecimento.

The forensic facial reconstruction corresponds to the rebuilding of the face of an individual, upon an unidentified skull. It can be two-dimensional or three-dimensional, performed manually or digitally. In the latter case, the advent of new information technologies has greatly contributed, especially with regard to the development of 3D image softwares, computed tomography and 3D scanner. Different techniques, equipments and softwares have been employed for this purpose. The characterization of facial reconstructions with hair, as hair, eyelashes and eyebrows, has been questioned, especially when there is no information about such data. This paper analyzes 3D digital forensic facial reconstructions and, based on evidence, proposes a pilot protocol for their confection and presentation. Digital facial reconstructions, made with 3ds Max software, without hair characterization, were made using three different tables of thickness of soft tissues. They were evaluated by 22 examiners, in a recognition test. In all cases, the target-subject was the most recognized subject, reaching the recognition rate of 45.45%. A proposal for a pilot protocol for the confection and presentation of forensic facial reconstructions is presented. The 3ds Max software is used to perform the facial reconstruction, and the ZBrush software to make the post-production (as wrinkles and lines). A prototype of the facial reconstruction is printed - it can facilitate the recognition of the subject. The authors state that the characterization with hair should not be performed, as it can impair the recognition.

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BACKGROUND: In the international scientific literature, there are few studies that emphasize the presence or absence of hair in forensic facial reconstructions. There are neither Brazilian studies concerning digital facial reconstructions without hair, nor research comparing recognition tests between digital facial reconstructions with hair and without hair. The miscegenation of Brazilian people is considerable. Brazilian people, and, in particular, Brazilian women, even if considered as Caucasoid, may present the hair in very different ways: curly, wavy or straight, blonde, red, brown or black, long or short, etc. For this reason, it is difficult to find a correct type of hair for facial reconstruction (unless, in real cases, some hair is recovered with the skeletal remains). AIMS AND METHODS: This study focuses on the performance of three different digital forensic facial reconstructions, without hair, of a Brazilian female subject (based on one international database and two Brazilian databases for soft facial-tissue thickness) and evaluates the digital forensic facial reconstructions comparing them to photographs of the target individual and nine other subjects, employing the recognition method. A total of 22 assessors participated in the recognition process; all of them were familiar with the 10 individuals who composed the face pool. RESULTS AND CONCLUSIONS: The target subject was correctly recognized by 41% of the 22 examiners in the International Pattern, by 32% in the Brazilian Magnetic Resonance Pattern and by 32% in the Brazilian Fresh Cadavers Pattern. The facial reconstructions without hair were correctly recognized using the three databases of facial soft-tissue thickness. The observed results were higher than the results obtained using facial reconstructions with hair, from the same skull, which can indicate that it is better to not use hair, at least when there is no information concerning its characteristics.

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Facial reconstruction is a method that seeks to recreate a person's facial appearance from his/her skull. This technique can be the last resource used in a forensic investigation, when identification techniques such as DNA analysis, dental records, fingerprints and radiographic comparison cannot be used to identify a body or skeletal remains. To perform facial reconstruction, the data of facial soft tissue thickness are necessary. Scientific literature has described differences in the thickness of facial soft tissue between ethnic groups. There are different databases of soft tissue thickness published in the scientific literature. There are no literature records of facial reconstruction works carried out with data of soft tissues obtained from samples of Brazilian subjects. There are also no reports of digital forensic facial reconstruction performed in Brazil. There are two databases of soft tissue thickness published for the Brazilian population: one obtained from measurements performed in fresh cadavers (fresh cadavers' pattern), and another from measurements using magnetic resonance imaging (Magnetic Resonance pattern). This study aims to perform three different characterized digital forensic facial reconstructions (with hair, eyelashes and eyebrows) of a Brazilian subject (based on an international pattern and two Brazilian patterns for soft facial tissue thickness), and evaluate the digital forensic facial reconstructions comparing them to photos of the individual and other nine subjects. The DICOM data of the Computed Tomography (CT) donated by a volunteer were converted into stereolitography (STL) files and used for the creation of the digital facial reconstructions. Once the three reconstructions were performed, they were compared to photographs of the subject who had the face reconstructed and nine other subjects. Thirty examiners participated in this recognition process. The target subject was recognized by 26.67% of the examiners in the reconstruction performed with the Brazilian Magnetic Resonance Pattern, 23.33% in the reconstruction performed with the Brazilian Fresh Cadavers Pattern and 20.00% in the reconstruction performed with the International Pattern, in which the target-subject was the most recognized subject in the first two patterns. The rate of correct recognitions of the target subject indicate that the digital forensic facial reconstruction, conducted with parameters used in this study, may be a useful tool.

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