Morphologie最新文献

Forensic odontologists often must identify human remains with damaged teeth. This damage is due to high-impact accidents, violence, or disasters. This 2-part study aimed to create two 3D digital models. They should show the destructive effects of physical and chemical agents on human teeth and popular dental materials. Researchers created an e-survey to investigate how digital models are perceived as an educational tool for Forensic Odontology. Also, a systematic review assessed experimental studies on the effects of high temperature on various prosthodontic materials. According to the results of the survey, most participants (n = 69; 79%) agreed that they would find a 3D model useful for training. Participants misidentify images of burned and broken teeth under Ellis and Davey system (1970). The systematic review identified dental implant and dental crown as the most studied prosthodontic materials exposed to heat. The researchers designed dental damage model 1 to represent restored and unrestored burnt teeth, postmortem pink teeth, and traumatic injuries. The dental damage model 2 was created to demonstrate the effects of various types of damage to different prosthetic and restorative dental materials, as well as the impact of acid, water, and burial on restorative materials as additional information. Both models were edited, sculpted and painted using 3D modelling software ZBrush (2020. 1.4) and Blender (version 3.6.2). The dental damage models were uploaded and labelled on Sketchfab (Cédric Pinson, Paris, France). The study's materials could transform the teaching of complex tooth changes.

The reduction of the pulpal space following the deposition of secondary dentin is a radiographically visible morphological feature associated with aging. Currently, there is no reference morphological sample for the Northern Brazilian population when it comes to the radiographically visible dental features for age estimation. This study aimed to test an existing method for age estimation based on the canine pulp/tooth area (PTA) ratio and develop a population-specific equation. The sample consisted of 100 peri-apical radiographs of Brazilian males (n = 46) and females (n = 54) from the Northern geographic region. The age of the sampled participants was between 18 and 72 years (mean age = 45.43 ± 14.39 years). The estimated age was obtained with the Cameriere's method. A statistically significant negative (r = −0.595) association was observed between the permanent canine PTA and the chronological age (P = 0.0001). A population-specific equation was structured with a 4-fold (75% × 25%) cross-validation, leading to a mean absolute error of 9.59 years, and root mean square error of 11.66 years (r² = 0.363). This study provided evidence to support the use of Cameriere's pulp/tooth area ratio for the radiographic dental age estimation of Northern Brazilian adults, especially adjusted with a population-specific equation.

Background

In elastic and resistance arteries, an elastin-rich membrane, the Internal Elastic Lamina (IEL), separates the tunica intima from the underlying tunica media. The IEL often appears wrinkled or corrugated in histological images. These corrugations are sometimes ascribed to vessel contraction ex vivo, and to fixation artifacts, and therefore regarded as not physiologically relevant. We examine whether the IEL remains corrugated even under physiological conditions.

Methods

The diameters of carotid arteries of anesthetized pigs were measured by ultrasound. The arteries were then excised, inflated within a conical sleeve, fixed, and imaged by confocal microscopy. The conical sleeve allows fixing each artery across a wide range of diameters, which bracket its ultrasound diameter. Thus the study was designed to quantify how corrugations change with diameter for a single artery, and test whether corrugations exist when the fixed artery matches the ultrasound diameter.

Results

At diameters below the ultrasound diameter (i.e. when the artery was constricted as compared to ultrasound conditions), the IEL corrugations were found to decrease significantly with increasing diameter, but not fully flatten at the ultrasound diameter. The contour length of the IEL was found to be roughly 10% larger than the circumference of the artery measured by ultrasound. The physiological diameter is likely to be even smaller than the ultrasound diameter since ultrasound was conducted with the animal under general anesthesia, which leads to vasodilation, suggesting a higher level of corrugation under physiological conditions. For arterial cross sections constricted below the ultrasound diameter, the IEL contour length decreased roughly with the square root of the diameter.

Conclusion

The primary conclusions of this study are: a) the IEL is corrugated when the artery is constricted and flattens as the artery diameter increases; b) the IEL is corrugated under physiological conditions and has a contour length at least 10% more than the physiological arterial diameter; and c) the IEL despite being relatively stiffer than the surrounding arterial layers, does not behave like an inextensible membrane.

The current bone report describes multiple openings identified in a dried scapula of a subject of unknown age and gender. Multiple openings (twelve) were identified in the subscapular fossa and were apparent at the infraspinatus fossa. These openings coexisted with a suprascapular foramen and an osteophyte at the inferomedial border of the foramen. In the current literature, two uncommon variants of the scapula were described: foramina and defects. It is still unclear how these two structures are differentiating. Both of them are results of abnormal ossification of the scapula. Clinicians should be aware of these variants because they may lead to misdiagnosis of malignancies, while the variants are benign entities.

Advances in computer hardware and software permit the reconstruction of physical objects digitally from digital camera images. Given the varying shapes and sizes of human bones, a comprehensive assessment is required to establish the accuracy of digital bone reconstructions from three-dimensional (3D) photogrammetry. Five human bones (femur, radius, scapula, vertebra, patella) were marked with pencil, to establish between 9 and 29 landmarks. The distances between landmarks were measured from the physical bones and digitized from 3D reconstructions. Images used for reconstructions were taken on two separate days, allowing for repeatability to be established. In comparison to physical measurements, the mean (± standard deviation) absolute differences were between 0.2 ± 0.1 mm and 0.4 ± 0.2 mm. The mean (± standard deviation) absolute differences between reconstructions were between 0.3 ± <0.1 mm and 0.4 ± 0.4 mm. The 3D photogrammetry procedures described are accurate and repeatable, permitting quantitative analyses to be conducted from digital reconstructions. Moreover, 3D photogrammetry may be used to capture and preserve anatomical materials for anatomy education.

Purpose

Photogrammetry is a technique which includes taking multiple digital photographs from various angles and using those photographs to create three-dimensional virtual models. We aimed to review the outcomes of the implementation of photogrammetry in anatomy education.

Methods

We searched PubMed, Scopus and Cochrane library for studies with purpose to explore the outcomes of the use of photogrammetry-based digital models in anatomy teaching. From each included paper we extracted: authors, number of participants, anatomical region of interest, educational outcomes, and their level according to Kirkpatrick hierarchy.

Results

Seven studies were included. Four of them concerned neuroanatomy and three of them concerned other systems. All studies comprised participants’ perceptions about the educational intervention, while two of them also evaluated anatomical knowledge acquisition. Overall, the participants rated photogrammetry-based models very highly and preferred them to other teaching tools. These models were also shown able to significantly enhance the anatomical knowledge.

Conclusions

Photogrammetry-based digital objects seem to have a promising anatomy teaching potential. The value of these objects seems to be especially pertinent in teaching the relatively complex field of neuroanatomy. Further research may investigate the effectiveness of photogrammetry-based models in comparison with other anatomy education tools, and with other methods of creation of three-dimensional virtual objects.

Objectives

In addition to bone fragility, patients with osteogenesis imperfecta (OI) type III have typical craniofacial abnormalities, such as a triangular face and maxillary micrognathism. However, in the osteogenesis imperfecta mouse (oim), a validated model of OI type III, few descriptions exist of craniofacial phenotype. Treatment of OI mostly consists of bisphosphonate administration. Cathepsin K inhibition has been tested as a promising therapeutic approach for osteoporosis and positive results were observed in long bones of cathepsin K knocked out oim (oim/CatK^–/–). This craniometry study aimed to highlight the craniofacial characteristics of oim and Cathepsin K KO mouse.

Materials and methods

We analyzed the craniofacial skeleton of 51 mice distributed in 4 genotype groups: Wt (control), oim, CatK^–/–, oim/CatK^–/–. The mice were euthanized at 13 weeks and their heads were analyzed using densitometric (pQCT), X-ray cephalometric, and histomorphometric methods.

Results

The craniofacial skeleton of the oim mouse is frailer than the Wt one, with a reduced thickness and mineral density of the cranial vault and mandibular ramus. Different cephalometric data attest a dysmorphism similar to the one observed in humans with OI type III. Those abnormalities were not improved in the oim/CatK^–/– group.

Conclusion

These results suggest that oim mouse could serve as a complete model of the human OI type III, including the craniofacial skeleton. They also suggest that invalidation of cathepsin K has no impact on the craniofacial abnormalities of the oim model.

Histology is part of the curricular base of all health courses, being the basis for understanding the composition of all tissues in the human body. Over the years, more and more technologies have entered the academic environment, with the aim of improving the teaching and learning process. Thus, the objective of this work was to conduct a systematic review on the use of digital technologies in teaching histology. The PICo strategy was used to develop the guiding question and the results were presented in a Prisma Flow. The following platforms were used to search for articles: PubMed, Embase. Web of Science, Science Direct, Medline, Scielo, Periódicos CAPES and LILACS, Open Gray and Google Scholar, with a time limit between 2012 and 2022. The results showed that this area is still little explored, with there not being a wide range of technologies being used and applied in teaching, with gamification and virtual microscopy being the most applied. However, it was realized that the use of these technologies can improve student performance and increase their interest in the subject. Therefore, these tools are great methods to reduce difficulties and encourage the development of a more receptive environment for the histology teaching and learning process.

The present article offers the facial approximation of the mummy of the ancient Egyptian adolescent named Minirdis (ca. 2300 years BP) by means of anatomical analysis of video-images and through a facial approximation protocol implemented on more historical personages. An evaluation of the mummy's endocast is also offered. A potential diagnosis of Sotos syndrome is cautiously considered but its inherent limitations are detailed. Finally, the methodology is presented as a valuable tool both for bio-historical research and for further studies on normal and pathologic morphologies of the cranio-facial district.