Volumetric Analysis of Carpal Bones by Sex with 3D Slicer Software Program / Análisis Volumétrico de los Huesos del Carpo por Sexo con el Programa de Software 3D Slicer

SUMMARY: In this study, we aim to share the volumes of the carpal bone and the ratio of these volumes to the total volume of wrist bones from Computed Tomography (CT) images obtained from individuals of different ages and sex using 3D Slicer. Right wrist CT images of 0.625 mm slice thickness of 42 healthy individuals (21 female, 21 male) of both sexes were included in our study. Volume calculations were made by loading the images into 3D Slicer, an open-source software package. In this study, mean capitate volume was the largest in both sexes (male 3479.9±679.2; female 2207.1±272.1 mm3), while pisiform had the smallest mean volume (male 810.0±141.2; female 566.6±97.7 mm3). This order was ordered from largest to smallest as hamate, scaphoid, trapezium, lunate, triquetrum, trapezoid, and pisiform. According to this study, carpal bone volumes were larger in males than in females (p0.05). In this study, it was seen that carpal bone volume differed according to sex. However, it was observed that the bone volumes of both sexes took up the same amount in the total bone volume. This information will be very useful in sex determination, 3D anatomical material creation, implant applications and reconstructive surgery.

Nuestro objetivo fue determinar los volúmenes de los huesos del carpo y la relación entre estos volúmenes y el volumen total de estos huesos a partir de imágenes de TC obtenidas de individuos de diferentes edades y sexos utilizando 3D Slicer. En el estudio se incluyeron imágenes de TC del carpo de la mano derecha de los participantes en el estudio, con un grosor de corte de 0,625 mm, en 42 individuos sanos (21 mujeres, 21 hombres) de ambos sexos. Los cálculos de volumen se realizaron cargando las imágenes en 3D Slicer, un paquete de software de código abierto. El volumen medio del hueso capitado fue el mayor en ambos sexos (hombre 3479,9 ± 679,2; mujer 2207,1 ± 272,1 mm3), mientras que el hueso pisiforme tuvo el volumen medio más pequeño (hombre 810,0 ± 141,2; mujer 566,6 ± 97,7 mm3). De mayor a menor el volumen de los otros huesos fue: hamato, escafoides, trapecio, lunato, piramidal, trapezoide y pisiforme. Según este estudio, los volúmenes óseos del carpo eran mayores en hombres que en mujeres (p0,05). En este estudio se observó que el volumen de los huesos del carpo difería según el sexo. Sin embargo, se observó que los volúmenes óseos de ambos sexos ocuparon la misma cantidad del volumen óseo total. Esta información será de gran utilidad en la determinación del sexo, creación de material anatómico 3D, aplicaciones de implantes y cirugía reconstructiva.

A true bicuspid tricuspid valve: 3D imaging to better understanding the forgotten valve.

Nowadays, understanding the anatomy of the tricuspid valve is crucial. The bicuspid tricuspid valve is a rare anatomical variation of this valve. We present highly illustrative images with 3D echo that allow a more realistic analysis of the forgotten valve.

Three-Dimensional Printing in Breast Reconstruction: Current and Promising Applications.

Three-dimensional (3D) printing is dramatically improving breast reconstruction by offering customized and precise interventions at various stages of the surgical process. In preoperative planning, 3D imaging techniques, such as computer-aided design, allow the creation of detailed breast models for surgical simulation, optimizing surgical outcomes and reducing complications. During surgery, 3D printing makes it possible to customize implants and precisely shape autologous tissue flaps with customized molds and scaffolds. This not only improves the aesthetic appearance, but also conforms to the patient's natural anatomy. In addition, 3D printed scaffolds facilitate tissue engineering, potentially favoring the development and integration of autologous adipose tissue, thus avoiding implant-related complications. Postoperatively, 3D imaging allows an accurate assessment of breast volume and symmetry, which is crucial in assessing the success of reconstruction. The technology is also a key educational tool, enhancing surgeon training through realistic anatomical models and surgical simulations. As the field evolves, the integration of 3D printing with emerging technologies such as biodegradable materials and advanced imaging promises to further refine breast reconstruction techniques and outcomes. This study aims to explore the various applications of 3D printing in breast reconstruction, addressing current challenges and future opportunities.

Relationship between soft tissue dimensions and tomographic radial root position classification system for immediate implant installation.

The aim of this study was to evaluate the relationship between soft tissue dimensions and radial root position (RRP) classification for immediate implant placement on maxillary anterior teeth. Maxillary anterior teeth (n = 420) were analyzed in the radial plane of cone beam computed tomography (CBCT) scans. Each tooth was classified according to its RRP: class I, (IA, IB); class II (IIA, IIB) class III; class IV, and class V. Soft tissue thickness at different landmarks, supracrestal soft tissue height, and crestal bone thickness were measured in CBCT. Keratinized tissue width was clinically measured. Gingival phenotype (thick or thin) was evaluated by transparency of the periodontal probe and at the landmark 2 mm from the gingival margin in CBCT. Class I tooth position accounted for 31.7%, class II for 45%, class III for 13.3%, class IV for 0.5%, and class V for 9.5%. The gingival phenotype was associated with RRP (χ2 test, p < 0.05). Soft tissue dimensions were significantly different over RRP classes (ANOVA and Tukey tests, p < 0.05). Types IA and IIA presented both thick soft and hard tissues. When planning immediate implants in the anterior maxilla, soft tissue dimensions evaluation should be incorporated into RRP classification to increase the accuracy and predictability of treatment outcomes.

Volumetric Temperature Mapping Using Light-Sheet Microscopy and Upconversion Fluorescence from Micro- and Nano-Rare Earth Composites.

We present a combination of light-sheet excitation and two-dimensional fluorescence intensity ratio (FIR) measurements as a simple and promising technique for three-dimensional temperature mapping. The feasibility of this approach is demonstrated with samples fabricated with sodium yttrium fluoride nanoparticles co-doped with rare-earth ytterbium and erbium ions (NaYF4:Yb3+/Er3+) incorporated into polydimethylsiloxane (PDMS) as a host material. In addition, we also evaluate the technique using lipid-coated NaYF4:Yb3+/Er3+ nanoparticles immersed in agar. The composite materials show upconverted (UC) fluorescence bands when excited by a 980 nm near-infrared laser light-sheet. Using a single CMOS camera and a pair of interferometric optical filters to specifically image the two thermally-coupled bands (at 525 and 550 nm), the two-dimensional FIR and, hence, the temperature map can be readily obtained. The proposed method can take optically sectioned (confocal-like) images with good optical resolution over relatively large samples (up to the millimetric scale) for further 3D temperature reconstruction.

Comprehensive in vitro polymer type, concentration, and size correlation analysis to microplastic toxicity and inflammation.

The ubiquitous nature of microplastic particles (MP) is a growing environmental and ecological concern due to their impact on aquatic and terrestrial systems and potentially on human health. The potential impact on human health may be due to MP daily exposure by several routes, but little is known about the cellular effects. Previous in vitro and in vivo studies have described inflammation, oxidative stress, and metabolic disruption upon plastic exposure, while the effect of individual plastic parameters is not fully unraveled. To this end, we investigated plastic exposure to different polymer types, sizes, and concentrations in three human cell lines (A549, HEK293, and HeLa). Particles were polystyrene (PS) or polymethylmethacrylate (PMMA) in three sizes and concentrations, and amine-modified PS served as positive control. After MP size validation using dynamic light scattering, a high-throughput high-content imaging-based and algorithm-driven multi-z-stack analysis was established to quantify intracellular fluorescent particle accumulation in 3D objects and cell maximum intensity projections. MP uptake correlated with concentration and for PS with size (1.040 µm), while for PMMA it was maximal for 400 nm MP. Uptake increased in HEK cells independent of MP parameters. Except for positive controls, no major effect on metabolic activity, viability, and cell cycle was observed, while intracellular thiol content and cytokine secretion were affected to a considerable extent. Interestingly, particle uptake was correlated significantly with particle size and concentration, underlining the dependence of MP parameters on biological effects.

In vivo three-dimensional cephalometric landmarks using CBCT for assessment of condylar volume and surface in individuals with Class I, II, and III malocclusions.

OBJECTIVE: To assess volume and surface of the mandibular condyle on cone beam computed tomography (CBCT) scans by comparing Class I, II, and III malocclusions. METHODS: CBCT scans of 55 patients were assessed to measure ANB angle, condyle volume, and surface by using VistaDent software. The values were compared between the different skeletal malocclusions and correlated to gender and sides. Kruskal-Wallis test was used for comparison of malocclusions and Mann-Whitney test and Wilcoxon test for comparisons of genders and sides. Statistical significance was defined as p < 0.05. RESULTS: There were no significant differences in volume (p = 0.588) and surface (p = 0.830) between the malocclusion classes. The comparison between sides showed a statistically significant difference for surface (p = 0.038). CONCLUSION: Condylar volume and surface evaluated on CBCT scans showed no statistically different values for Class I, II, and III malocclusions.

Relato de caso clínico de preenchimento labial com ácido hialurônico e avaliações volumétricas através de software de análise facial 3d / Clinical case report of hyaluronic acid lip filler and volumetric evaluations using 3d facial analysis software / Reporte de caso clínico de relleno labial con ácido hialurónico y evaluaciones volumétricas utilizando software de análisis facial 3d

A análise facial consiste em uma etapa importante do diagnóstico e avaliação dos resultados obtidos na harmonização orofacial. Para avaliação dos resultados de procedimentos estéticos, fotografias são muito utilizadas, porém novas ferramentas são necessárias para facilitar a visualização dos pacientes quanto aos ganhos estéticos. Os scanners faciais 3D surgem como alternativa para tal finalidade. O objetivo deste estudo foi analisar, através de fotografias e escaneamento 3D da face, o ganho de volume labial após intervenção de preenchimento. A paciente apresentava insatisfação com relação aos seus lábios. Durante a avaliação, constatou-se ausência de volume e contorno labial. Antes de iniciar o procedimento, realizou-se protocolo fotográfico e escaneamento facial (E1). Para o procedimento, foi utilizada uma seringa de 1 mL de ácido hialurônico. O escaneamento foi feito no pós-imediato (E2), após 10 dias (E3) e após 40 dias da intervenção (E4). Nesta mesma consulta após 40 dias, foi realizado injeção da segunda seringa de ácido hialurônico escaneamento do pós-imediato (E5). Após 40 dias, a paciente voltou (E6). Após análise comparativa das malhas, foi possível verificar ganho de 3 mm entre E1 e E2. Na comparação do pré (E1) e após 10 dias (E3), verificou-se volumização total de 1,85 mm, demonstrando que quase 40% do volume no pós-imediato é edema. Em E6, após 40 dias da aplicação da segunda seringa, foi possível quantificar ganho de 2,12 mm no lábio superior quando comparado a E1. Pode-se concluir que o escaneamento 3D contribui expressivamente para avaliação dos resultados alcançados em procedimentos estéticos.

Facial analysis is an important stage in the diagnosis and evaluation of the results obtained in orofacial harmonization. To evaluate the results of aesthetic procedures, photographs are widely used, but new tools are needed to facilitate patient visualization of aesthetic gains. 3D facial scanners have emerged as an alternative for this purpose. The aim of this study was to analyze, by means of photographs and 3D facial scanning, the labial volume gain after a filling intervention. The patient was dissatisfied with her lips. During the evaluation, it was observed the absence of lip volume and contour. Before starting the procedure, a photographic protocol and facial scanning (S1) were performed. A 1 mL syringe of hyaluronic acid was used for the procedure. The scanning was done post-immediately (S2), 10 days (S3) and 40 days after the intervention (S4). In the same appointment after 40 days, the second syringe of hyaluronic acid was injected and scanned post-immediate (S5). After 40 days, the patient returned (E6). After comparative mesh analysis, it was possible to verify a 3 mm gain between S1 and S2. In the comparison of pre (S1) and after 10 days (S3), there was a total volumization of 1.85 mm, showing that almost 40% of the volume in the post-immediate period is edema. In S6, 40 days after the application of the second syringe, it was possible to quantify a gain of 2.12 mm in the upper lip when compared to S1. It can be concluded that 3D scanning contributes expressively to the evaluation of the results achieved in aesthetic procedures.

El análisis facial es una etapa importante en el diagnóstico y la evaluación de los resultados obtenidos en la armonización orofacial. Para evaluar los resultados de los procedimientos estéticos, las fotografías son ampliamente utilizadas, pero se necesitan nuevas herramientas que faciliten al paciente la visualización de las ganancias estéticas. Los escáneres faciales 3D han surgido como una alternativa para este fin. El objetivo de este estudio fue analizar, mediante fotografías y escaneado facial 3D, la ganancia de volumen labial tras una intervención de relleno. La paciente estaba insatisfecha con sus labios. Durante la evaluación, se observó la ausencia de volumen y contorno labial. Antes de iniciar el procedimiento, se realizó un protocolo fotográfico y un escaneado facial (S1). Para el procedimiento se utilizó una jeringa de 1 ml de ácido hialurónico. La exploración se realizó inmediatamente después (S2), a los 10 días (S3) y a los 40 días de la intervención (S4). En la misma consulta, a los 40 días, se realizó la inyección de la segunda jeringa de ácido hialurónico tras la exploración inmediata (S5). A los 40 días, la paciente regresó (E6). Tras el análisis comparativo de las mallas, se pudo comprobar una ganancia de 3 mm entre S1 y S2. En la comparación del pre (S1) y después de 10 días (S3), hubo una volumización total de 1,85 mm, demostrando que casi 40% del volumen post-immediato es edema. En S6, 40 días después de la aplicación de la segunda jeringa, fue posible cuantificar una ganancia de 2,12 mm en el labio superior en comparación con S1. Se puede concluir que el escaneo 3D contribuye expresivamente para la evaluación de los resultados alcanzados en procedimientos estéticos.

Quantitative Mobility Analysis of the Face and its Relevance for Surgical and Non-surgical Aesthetic Facial Procedures.

BACKGROUND: Understanding the degree of facial mobility upon postural changes is of great clinical relevance especially if facial assessment, facial measurements and/or facial markings are done in an upright position, but facial procedures are performed in a supine position. OBJECTIVE: The objective of this study is to investigate regional facial skin displacement and facial volume changes in individuals between upright and supine positions. METHODS: This multi-center study analyzed a total of 175 study participants with a mean age of 35.0 (10.2) years and a mean body mass index of 24.71 (3.5) kg/m2. 3D surface scanning technology with automated registration and alignment was utilized, and multivariate analyses were performed with adjustment for age, gender, body mass index, facial skin sagging and laxity. RESULTS: The medial face displaced less than the lateral face in both cranial (0.88 mm) and in lateral (0.76 mm) directions, and the lower face displaced more than the middle face in both cranial (1.17 mm) and lateral directions (1.37 mm). Additionally, the medial face lost, on average, 3.00cc whereas the lateral face increased by 5.86cc in volume; the middle face increased by 2.95cc, whereas the lower face decreased by 0.98cc in volume. All p < 0.001. CONCLUSION: Practitioners should be mindful that there is a statistically significant change in facial soft tissues between the upright and supine positions and that the magnitude of the change does not necessarily reflect on the aging process alone but is a multi-factorial process which should be individualized for each patient's needs. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Single-Pixel Near-Infrared 3D Image Reconstruction in Outdoor Conditions.

In the last decade, the vision systems have improved their capabilities to capture 3D images in bad weather scenarios. Currently, there exist several techniques for image acquisition in foggy or rainy scenarios that use infrared (IR) sensors. Due to the reduced light scattering at the IR spectra it is possible to discriminate the objects in a scene compared with the images obtained in the visible spectrum. Therefore, in this work, we proposed 3D image generation in foggy conditions using the single-pixel imaging (SPI) active illumination approach in combination with the Time-of-Flight technique (ToF) at 1550 nm wavelength. For the generation of 3D images, we make use of space-filling projection with compressed sensing (CS-SRCNN) and depth information based on ToF. To evaluate the performance, the vision system included a designed test chamber to simulate different fog and background illumination environments and calculate the parameters related to image quality.

Accuracy of a handheld 3D imaging system for child anthropometric measurements in population-based household surveys and surveillance platforms: an effectiveness validation study in Guatemala, Kenya, and China.

BACKGROUND: An efficacy evaluation of the AutoAnthro system to measure child (0-59 months) anthropometry in the United States found 3D imaging performed as well as gold-standard manual measurements for biological plausibility and precision. OBJECTIVES: We conducted an effectiveness evaluation of the accuracy of the AutoAnthro system to measure 0- to 59-month-old children's anthropometry in population-based surveys and surveillance systems in households in Guatemala and Kenya and in hospitals in China. METHODS: The evaluation was done using health or nutrition surveillance system platforms among 600 children aged 0-59 months (Guatemala and Kenya) and 300 children aged 0-23 months (China). Field team anthropometrists and their assistants collected manual and scan anthropometric measurements, including length or height, midupper arm circumference (MUAC), and head circumference (HC; China only), from each child. An anthropometry expert and assistant later collected both manual and scan anthropometric measurements on the same child. The expert manual measurements were considered the standard compared to field team scans. RESULTS: Overall, in Guatemala, Kenya, and China, for interrater accuracy, the average biases for length or height were -0.3 cm, -1.9 cm, and -6.2 cm, respectively; for MUAC were 0.9 cm, 1.2 cm, and -0.8 cm, respectively; and for HC was 2.4 cm in China. The inter-technical errors of measurement (inter-TEMs) for length or height were 2.8 cm, 3.4 cm, 5.5 cm, respectively; for MUAC were 1.1 cm, 1.5 cm, and 1.0 cm, respectively; and for HC was 2.8 cm in China. For intrarater precision, the absolute mean difference and intra-TEM (interrater, intramethod TEM) were 0.1 cm for all countries for all manual measurements. For scans, overall, absolute mean differences for length or height were 0.4-0.6 cm; for MUAC were 0.1-0.1 cm; and for HC was 0.4 cm. For the intra-TEM, length or height was 0.5 cm in Guatemala and China and 0.7 cm in Kenya, and other measurements were ≤0.3 cm. CONCLUSIONS: Understanding the factors that cause the many poor scan results and how to correct them will be needed prior to using this instrument in routine, population-based survey and surveillance systems.

Accuracy of three-dimensional soft tissue profile prediction in orthognathic surgery.

PURPOSE: To evaluate the accuracy of three-dimensional (3D) soft tissue prediction in bimaxillary orthognathic surgery. METHODS: Cone-beam computed tomographs of 88 patients with class II (n = 46) and class III (n = 42) malocclusions, who underwent bimaxillary orthognathic surgery, were included in this retrospective study. 3D soft tissue prediction and postoperative outcome were compared by using ten landmarks of facial soft tissues. Patients' sex and age were also assessed. Results were analyzed using a mixed model methodology (p < 0.05). RESULTS: The success criterion adopted was a mean discrepancy of < 2 mm. Most mandibular landmarks indicated a tendency for underprediction with a downward direction in class II patients, with some values > 2 mm. In class III, there was overprediction with a downward direction for the mandibular landmarks, with values < 2 mm. More accurate results were found in female and older patients. CONCLUSIONS: 3D surgical planning showed clinically acceptable results for predicting soft tissues in patients undergoing bimaxillary orthognathic surgery, with more accurate results for class III patients. Although some differences were found when age and sex were interacted, a consistent association between these variables could not be stated. These results support the clinician, as accuracy can provide a strong guide to the surgeon when planning surgical orthodontic treatment.

Spiral SAR Imaging with Fast Factorized Back-Projection: A Phase Error Analysis.

This paper presents a fast factorized back-projection (FFBP) algorithm that can satisfactorily process real P-band synthetic aperture radar (SAR) data collected from a spiral flight pattern performed by a drone-borne SAR system. Choosing the best setup when processing SAR data with an FFBP algorithm is not so straightforward, so predicting how this choice will affect the quality of the output image is valuable information. This paper provides a statistical phase error analysis to validate the hypothesis that the phase error standard deviation can be predicted by geometric parameters specified at the start of processing. In particular, for a phase error standard deviation of ~12°, the FFBP is up to 21 times faster than the direct back-projection algorithm for 3D images and up to 13 times faster for 2D images.

Two and Three-dimensional Parameters in Cone-beam Computed Tomography Monitoring of Apical Periodontitis in Traumatized Teeth: Case Report and Long-term Follow-up.

Assessment of apical periodontitis (AP) is a challenging task. This case report highlights the CBCT diagnosis and monitoring of periapical radiolucency (PR) using ITK-SNAP software 3.8v in a complex clinical scenario of three traumatized anterior teeth. An 11-year-old male patient complained of recurrent swelling and pain in the maxillary incisor region (teeth #11 and #21). His parents reported a history of traumatic injury affecting these teeth two years back. Digital periapical radiographic (DPR) and cone-beam computed tomography (CBCT) were requested. PR was identified on teeth #11, #21, and # 22. In tooth #22, besides a PR, an area suggesting internal root resorption or oblique root fracture was observed. The teeth were shaped and dressing with calcium hydroxide Ca(OH)2. MTA repair was delivered to the apical portion of the canals (approximately 3 mm). The remainder of the canal was filled with thermoplastic gutta-percha and Endosequence sealer. After one year, the patient returned complaining of pain in tooth #11. Radiographically, the PR of tooth #11 did not reduce. A CBCT was taken, showing a reduction of radiolucency. The patient was clinical and radiographically re-evaluated for 6 months, and he remained asymptomatic. After three years of follow-up, the patient suffered a new trauma on teeth #11 and #21. As tooth #11 presents mobility and biting pain, a new CBCT was requested due to the risk of a possible root fracture. So, the PR was synchronously monitored with linear measurements and volumetric analysis using ITK-SNAP software 3.8v. In this case, the volumetric evaluation was essential to identify the PR's correct dimensions, reducing image interpretation's subjectivity. At 48-month follow-up, the patient was symptoms free and radiographically showed a reduction in the PR's size, compatible with osseous healing.

3D forensic facial approximation: Implementation protocol in a forensic activity.

The primary objective of this paper is to report on the successful implementation of forensic facial approximation in a real case in the forensic context. A three-dimensional (3D) facial approximation protocol of the skull was performed with free software, applying techniques in a virtual environment that have already been consolidated in the literature. The skull was scanned with the photogrammetry technique, the digital replica was imported in the Blender software (Blender Foundation, Amsterdam) and individualized model sketches of the face were traced with the MakeHuman software (MakeHuman Org) according to the anthropological profile of the victim. The face created was imported in Blender, where it was adapted, modeled, and sculpted on the 3D skull and its soft tissue markers, using an American open-source application of the technique in the digital environment. The face created in a virtual environment was recognized and legal identification procedures were started, resulting in the more agile delivery of the disappeared body to its next of kin. It is therefore concluded that facial approximation may not be a primary method of human identification, but it can be satisfactorily applied in the forensic field as an individual recognition resource. It has great value in narrowing the search, reducing the number of alleged victims, and leading to identification tests, therefore significantly reducing the number of genetic DNA (deoxyribonucleic acid) tests-which are considered costly for the State or Federation-and consequently reducing the waiting time before delivery of the body to its family.

Accuracy of three-dimensional virtual simulation of the soft tissues of the face in OrtogOnBlender for correction of class II dentofacial deformities: an uncontrolled experimental case-series study.

PURPOSE: To assess whether virtual simulations of the projection of the soft tissues of the face after class II bimaxillary orthognathic surgery, generated from 3D reconstruction of preoperative computed tomography (CT) scans, differed significantly from the actual soft tissue profile obtained in the late postoperative period (beyond 6 months). Secondarily, to validate the accuracy of a free, open-source software suite for virtual soft tissue planning in orthognathic surgery. METHODS: Helical CT scans were obtained pre- and postoperatively from 16 patients with Angle class II malocclusion who underwent bimaxillary orthognathic surgery. A comparative study between soft tissue meshes constructed for surgical simulation (M1) and the actual meshes obtained from postoperative scans (M2) was then performed. To establish the accuracy of 3D facial soft tissue simulation in a free and open-source software suite (OrtogOnBlender-OOB), 17 predetermined anatomic landmarks were measured in M1 and M2 scans after alignment of cranial structures. RESULTS: The mean error between preoperative simulations and actual postoperative findings was < 2 mm for all anthropometric landmarks. The overall average error for the facial soft tissues was 1.07 mm. CONCLUSION: Comparison between preoperative simulation (M1) and actual postoperative findings (M2) showed clinically relevant ability of the method to reproduce actual surgical movement reliably (< 2-mm error). OOB is capable of accurate soft tissue planning for orthognathic surgery, but mesh deformation methods still require improvement. TRIAL REGISTRATION: RBR-88jff9. Retrospectively registered at Brazilian Registry of Clinical trials-ReBec ( http://www.ensaiosclinicos.gov.br ) May 06, 2020.

The Use of a 3D Simulator Software and 3D Printed Biomodels to Aid Autologous Breast Reconstruction.

Aesthetically pleasing and symmetrical breasts are the goal of reconstructive breast surgery. However, multiple procedures are sometimes needed to improve a reconstructed breast's symmetry and appearance. Since all breasts vary in terms of volume, height, width, projection, orientation, and shape, the lack of attention to these details at the moment of flap shaping in autologous reconstruction can lead to poor results. Recent advances in 3-dimensional (3D) surface imaging and printing technologies have allowed for improvement in autologous breast reconstruction symmetry. While 3D printing technology is becoming faster, more accurate, and less expensive, the technology required to obtain proper 3D breast images remains expensive, including laser scanners or 3D photogrammetric cameras. In this study, we present a novel use of an aesthetic surgery simulator software as an affordable alternative to obtaining 3D breast images and creating 3D printed biomodels to aid in the precise shaping of the flap. This approach aims to optimize aesthetic results in autologous breast reconstruction avoiding surgical revisions and reducing surgical times. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Effect of micro-computed tomography reconstruction protocols on bone fractal dimension analysis.

OBJECTIVES: To evaluate the influence of the level of three micro-CT reconstruction tools: beam-hardening correction (BHC), smoothing filter (SF), and ring artefact correction (RAC) on the fractal dimension (FD) analysis of trabecular bone. METHODS: Five Wistar rats' maxillae were individually scanned in a SkyScan 1174 micro-CT device, under the following settings: 50 kV, 800 µA, 10.2 µm voxel size, 0.5 mm Al filter, rotation step 0.5°, two frames average, 180° rotation and scan time of 35 min. The raw images were reconstructed under the standard protocol (SP) recommended by the manufacturer, a protocol without any artefact correction tools (P0) and 35 additional protocols with different combinations of SF, RAC and BHC levels. The same volume of interest was established in all reconstructions for each maxilla and the FD was calculated using the Kolmogorov (box counting) method. One-way ANOVA with Dunnet's post-hoc test was used to compare the FD of each reconstruction protocol (P0-P35) with the SP (α = 5%). Multiple linear regression verified the dependency of reconstruction tools in FD. RESULTS: Overall, FD values are not dependent on RAC (p = 0.965), but increased significantly when the level of BHC and SF increased (p < 0.001). FD values from protocols with BHC at 45% combined with SF of 2, and BHC at 30% combined with SF of 4 or 6 had no statistical difference compared to SP. CONCLUSIONS: BHC and SF tools affect the FD values of micro-CT images of the trabecular bone. Therefore, these reconstruction parameters should be standardized when the FD is analyzed.

Comparison of maxillomandibular asymmetries in adult patients presenting different sagittal jaw relationships

ABSTRACT Objective: The present study aims at using cone beam computed tomography (CBCT) to analyze the maxillomandibular characteristics present in adults with mandibular asymmetries and different sagittal jaw relationships. Methods: 360 patients were selected and divided into three groups (Class I, Class II, and Class III), with 120 individuals per group. The groups were then subdivided according to the intensity of lateral deviation of the gnathion point, into: 1) relative symmetry, 2) moderate asymmetry, and 3) severe asymmetry. Three planes of reference were established in the CBCT images and several measurements were taken to compare the bilateral skeletal differences between the intensities of asymmetry for the different sagittal jaw relationships. Results: When the groups were compared by the intensity of asymmetry, significant differences among patients with relative symmetry and moderate to severe asymmetry were found. This was especially noticed for severe asymmetry, suggesting that the deviation of the chin did not constitute the only morphological alteration for these patients, especially because a series of measurements showed significant bilateral differences. When comparing sagittal jaw relationships, the only significant finding was the vertical positioning of the gonion between Class II and III patients with severe asymmetry. Conclusions: When comparing the three sagittal jaw relationships with the same intensity of asymmetry, most maxillofacial aspects were quite similar. The only difference was found for patients with severe asymmetry, as the individuals with Class II showed greater bilateral difference in the vertical positioning of the gonion, when compared to patients with Class III.

RESUMO Objetivo: o presente estudo teve como objetivo analisar, por meio de tomografia computadorizada de feixe cônico (TCFC), as características esqueléticas maxilomandibulares presentes em adultos com diferentes graus de assimetria mandibular e diferentes relações esqueléticas sagitais. Métodos: foram selecionados 360 pacientes, os quais foram divididos em três grupos, com 120 indivíduos cada (Classe I, Classe II e Classe III). Cada grupo foi, ainda, subdividido de acordo com a intensidade do desvio lateral do mento: 1) simetria relativa; 2) assimetria moderada; e 3) assimetria severa. Três planos de referência foram estabelecidos nas imagens de TCFC e várias medidas foram realizadas, sendo comparadas as diferenças esqueléticas bilaterais existentes entre os graus de assimetria em cada grupo, nas diferentes relações esqueléticas sagitais. Resultados: quando comparados os grupos pelos graus de assimetria, existiram diferenças significativas entre pacientes com simetria relativa e pacientes assimétricos, especialmente para a assimetria severa, sugerindo que o desvio do mento não constitui a única alteração morfológica para esses pacientes, especialmente porque uma série de medidas apresentou diferenças bilaterais significativas. Quando comparadas as relações sagitais entre si, não foram encontradas diferenças significativas, exceto para o posicionamento vertical do gônio entre as Classe II e III na assimetria severa. Conclusão: ao comparar a mesma intensidade de assimetria entre as diferentes relações esqueléticas sagitais, pouca diferença pôde ser observada. A única diferença encontrada foi em pacientes com assimetria severa, na qual os indivíduos com Classe II apresentaram maior diferença bilateral no posicionamento vertical do gônio, quando comparados àqueles com Classe III.