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1.
Artículo en Inglés | MEDLINE | ID: mdl-38822952

RESUMEN

Eclampsia is one of the most dangerous complications of pregnancy and has a high incidence in developing countries. It is characterized by coma and the occurrence of generalized tonic-clonic seizures in pregnant women with hypertension. Deep bites on the tongue and other orofacial injuries have been described as consequences of these seizures. We present a case of death associated with eclampsia in which the bite during the seizure episode caused almost total amputation of an enlarged tongue (macroglossia). The medico-legal value of this finding and the situation due to antecedent pathological conditions and lack of routine screening in pregnant women who may migrate legally or illegally to give birth with better medical care are discussed.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38630206

RESUMEN

This study presents a novel conservative technique to increase oral opening and overcome rigor mortis during medicolegal autopsy (MLA). The method proposes a myotomy of the temporalis and masseter muscles, taking advantage of the incisions of the cranial opening procedures, to achieve a significant oral opening (≥ 30 mm) in fresh cadavers with established rigor mortis without altering facial aesthetics. The study was performed on 48 individuals aged between 18 and 66 years (20 males and 28 females) who were autopsied at the Instituto Nacional de Patología Forense Dr. Sergio Sarita Valdez (Santo Domingo, Dominican Republic). The proposed technique not only allowed the oral access to all autopsied cadavers but also complied with current ethical standards for preserving facial aesthetics, taking into account the concerns of family members by allowing respectful viewing of the cadaver. This advancement not only contributes to the efficiency of oral autopsies but also influences public perception of forensic procedures and highlights the importance of ethical and aesthetic considerations in the context of MLAs. The proposed technique represents a significant step towards more respectful and ethical forensic practices, and offers practical advantages for a more complete and accurate assessment during MLA.

3.
Phys Med Biol ; 69(10)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38593826

RESUMEN

Objective. Newer cone-beam computed tomography (CBCT) imaging systems offer reconstruction algorithms including metal artifact reduction (MAR) and extended field-of-view (eFoV) techniques to improve image quality. In this study a new CBCT imager, the new Varian HyperSight CBCT, is compared to fan-beam CT and two CBCT imagers installed in a ring-gantry and C-arm linear accelerator, respectively.Approach. The image quality was assessed for HyperSight CBCT which uses new hardware, including a large-size flat panel detector, and improved image reconstruction algorithms. The decrease of metal artifacts was quantified (structural similarity index measure (SSIM) and root-mean-squared error (RMSE)) when applying MAR reconstruction and iterative reconstruction for a dental and spine region using a head-and-neck phantom. The geometry and CT number accuracy of the eFoV reconstruction was evaluated outside the standard field-of-view (sFoV) on a large 3D-printed chest phantom. Phantom size dependency of CT numbers was evaluated on three cylindrical phantoms of increasing diameter. Signal-to-noise and contrast-to-noise were quantified on an abdominal phantom.Main results. In phantoms with streak artifacts, MAR showed comparable results for HyperSight CBCT and CT, with MAR increasing the SSIM (0.97-0.99) and decreasing the RMSE (62-55 HU) compared to iterative reconstruction without MAR. In addition, HyperSight CBCT showed better geometrical accuracy in the eFoV than CT (Jaccard Conformity Index increase of 0.02-0.03). However, the CT number accuracy outside the sFoV was lower than for CT. The maximum CT number variation between different phantom sizes was lower for the HyperSight CBCT imager (∼100 HU) compared to the two other CBCT imagers (∼200 HU), but not fully comparable to CT (∼50 HU).Significance. This study demonstrated the imaging performance of the new HyperSight CBCT imager and the potential of applying this CBCT system in more advanced scenarios by comparing the quality against fan-beam CT.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Humanos , Artefactos , Control de Calidad
4.
Phys Imaging Radiat Oncol ; 29: 100566, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38487622

RESUMEN

Background and purpose: Dose calculation on cone-beam computed tomography (CBCT) images has been less accurate than on computed tomography (CT) images due to lower image quality and discrepancies in CT numbers for CBCT. As increasing interest arises in offline and online re-planning, dose calculation accuracy was evaluated for a novel CBCT imager integrated into a ring gantry treatment machine. Materials and methods: The new CBCT system allowed fast image acquisition (5.9 s) by using new hardware, including a large-size flat panel detector, and incorporated image-processing algorithms with iterative reconstruction techniques, leading to accurate CT numbers allowing dose calculation. In this study, CBCT- and CT-based dose calculations were compared based on three anthropomorphic phantoms, after CBCT-to-mass-density calibration was performed. Six plans were created on the CT scans covering various target locations and complexities, followed by CBCT to CT registrations, copying of contours, and re-calculation of the plans on the CBCT scans. Dose-volume histogram metrics for target volumes and organs-at-risk (OARs) were evaluated, and global gamma analyses were performed. Results: Target coverage differences were consistently below 1.2 %, demonstrating the agreement between CT and re-calculated CBCT dose distributions. Differences in Dmean for OARs were below 0.5 Gy for all plans, except for three OARs, which were below 0.8 Gy (<1.1 %). All plans had a 3 %/1mm gamma pass rate > 97 %. Conclusions: This study demonstrated comparable results between dose calculations performed on CBCT and CT acquisitions. The new CBCT system with enhanced image quality and CT number accuracy opens possibilities for off-line and on-line re-planning.

6.
Int. j. morphol ; 42(1): 185-196, feb. 2024. ilus, tab, graf
Artículo en Inglés | LILACS | ID: biblio-1528838

RESUMEN

SUMMARY: The new paradigm in Forensic Sciences initiated by the entry of genetics (the current standard of legal evidence) and accentuated by recognized wrongful convictions derived from experts today in the eye of criticism, has highlighted the potential for bias and error in forensic disciplines when they depend on human interpretation and subjectivity, which has not been avoided by Forensic Odontology (FO). However, a subjective judgment is not necessarily wrong, so the refinement of processes, the development of standards, and robust research can contribute to the validity of interpretation to increase objectivity. Latin America (LATAM) has its own realities and needs, which have conditioned the priorities and objectives of FO research. A scoping review is presented to systematically map the investigation of LATAM researchers and identify the objective or subjective nature of their assessments. LATAM shows interesting productivity and intentions to adhere to international standards, with Brazil leading this research significantly, followed by Chile and Colombia, among others. However, there is a disproportionate approach in certain lines of research (dental age estimation), and needs to address other quantitative studies, and to improve the visibility of the LATAM FO research.


El nuevo paradigma en ciencias forenses iniciado por la entrada de la genética (el actual estándar de la evidencia jurídica), y acentuado por reconocidas condenas injustas derivadas de pericias hoy en el ojo de la crítica, ha destacado el potencial de sesgo y error que poseen algunas disciplinas forenses cuando dependen de la interpretación humana y la subjetividad, lo cual no ha sido ajeno a la odontología forense (OF). Sin embargo, un juicio subjetivo no necesariamente es erróneo, con lo que el refinamiento de procesos, el desarrollo de estándares y la investigación robusta pueden contribuir a validar esa interpretación para aumentar su objetividad. Latinoamérica (LATAM) posee realidades y necesidades propias que han condicionado las prioridades y objetivos de la investigación en OF. Se presenta una revisión con búsqueda sistemática para mapear sistemáticamente la investigación en OF realizada por investigadores latinoamericanos, así como identificar la naturaleza objetiva o subjetiva de sus evaluaciones. LATAM demuestra una productividad interesante e intenciones de adherirse a estándares internacionales, con Brasil liderando significativamente esta investigación, seguido por Chile y Colombia entre otros. Sin embargo, se observa un enfoque desproporcionado en ciertas líneas de investigación (estimación de edad dental particularmente), y necesidad tanto de abordar otros estudios cuantitativos como de mejorar la visibilidad de la investigación latinoamericana en OF.


Asunto(s)
Humanos , Investigación , Odontología Forense , Interpretación Estadística de Datos , Investigación Cualitativa , América Latina
7.
J Evol Biol ; 36(11): 1595-1608, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37885128

RESUMEN

Hybridization could be considered part of the evolutionary history of many species. The hybridization among sea turtle species on the Brazilian coast is atypical and occurs where nesting areas and reproductive seasons overlap. Integrated analysis of morphology and genetics is still scarce, and there is no evidence of the parental chromosome set distribution in sea turtle interspecific hybrids. In this study, chromosome markers previously established for pure sea turtle species were combined with morphological and molecular analyses aiming to recognize genetic composition and chromosome sets in possible interspecific hybrids initially identified by mixed morphology. The data showed that one hybrid could be an F2 individual among Caretta caretta × Eretmochelys imbricata × Chelonia mydas, and another is resulting from backcross between C. caretta × Lepidochelys olivacea. Native alleles of different parental lineages were reported in the hybrids, and, despite this, it was verified that the hybrid chromosome sets were still balanced. Thus, how sea turtle hybridism can affect genetic features in the long term is a concern, as the implications of the crossing-over in hybrid chromosomal sets and the effects on genetic function are still unpredictable.


Asunto(s)
Tortugas , Animales , Tortugas/genética , Evolución Biológica , Reproducción , Cromosomas , Análisis Citogenético
8.
Med Phys ; 50(8): e946-e960, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37427750

RESUMEN

The introduction of model-based dose calculation algorithms (MBDCAs) in brachytherapy provides an opportunity for a more accurate dose calculation and opens the possibility for novel, innovative treatment modalities. The joint AAPM, ESTRO, and ABG Task Group 186 (TG-186) report provided guidance to early adopters. However, the commissioning aspect of these algorithms was described only in general terms with no quantitative goals. This report, from the Working Group on Model-Based Dose Calculation Algorithms in Brachytherapy, introduced a field-tested approach to MBDCA commissioning. It is based on a set of well-characterized test cases for which reference Monte Carlo (MC) and vendor-specific MBDCA dose distributions are available in a Digital Imaging and Communications in Medicine-Radiotherapy (DICOM-RT) format to the clinical users. The key elements of the TG-186 commissioning workflow are now described in detail, and quantitative goals are provided. This approach leverages the well-known Brachytherapy Source Registry jointly managed by the AAPM and the Imaging and Radiation Oncology Core (IROC) Houston Quality Assurance Center (with associated links at ESTRO) to provide open access to test cases as well as step-by-step user guides. While the current report is limited to the two most widely commercially available MBDCAs and only for 192 Ir-based afterloading brachytherapy at this time, this report establishes a general framework that can easily be extended to other brachytherapy MBDCAs and brachytherapy sources. The AAPM, ESTRO, ABG, and ABS recommend that clinical medical physicists implement the workflow presented in this report to validate both the basic and the advanced dose calculation features of their commercial MBDCAs. Recommendations are also given to vendors to integrate advanced analysis tools into their brachytherapy treatment planning system to facilitate extensive dose comparisons. The use of the test cases for research and educational purposes is further encouraged.


Asunto(s)
Braquiterapia , Braquiterapia/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Algoritmos , Informe de Investigación , Método de Montecarlo , Radiometría
9.
Br J Radiol ; 96(1149): 20230110, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37493227

RESUMEN

OBJECTIVE: Several studies have shown that dual-energy CT (DECT) can lead to improved accuracy for proton range estimation. This study investigated the clinical benefit of reduced range uncertainty, enabled by DECT, in robust optimisation for neuro-oncological patients. METHODS: DECT scans for 27 neuro-oncological patients were included. Commercial software was applied to create stopping-power ratio (SPR) maps based on the DECT scan. Two plans were robustly optimised on the SPR map, keeping the beam and plan settings identical to the clinical plan. One plan was robustly optimised and evaluated with a range uncertainty of 3% (as used clinically; denoted 3%-plan); the second plan applied a range uncertainty of 2% (2%-plan). Both plans were clinical acceptable and optimal. The dose-volume histogram parameters were compared between the two plans. Two experienced neuro-radiation oncologists determined the relevant dose difference for each organ-at-risk (OAR). Moreover, the OAR toxicity levels were assessed. RESULTS: For 24 patients, a dose reduction >0.5/1 Gy (relevant dose difference depending on the OAR) was seen in one or more OARs for the 2%-plan; e.g. for brainstem D0.03cc in 10 patients, and hippocampus D40% in 6 patients. Furthermore, 12 patients had a reduction in toxicity level for one or two OARs, showing a clear benefit for the patient. CONCLUSION: Robust optimisation with reduced range uncertainty allows for reduction of OAR toxicity, providing a rationale for clinical implementation. Based on these results, we have clinically introduced DECT-based proton treatment planning for neuro-oncological patients, accompanied with a reduced range uncertainty of 2%. ADVANCES IN KNOWLEDGE: This study shows the clinical benefit of range uncertainty reduction from 3% to 2% in robustly optimised proton plans. A dose reduction to one or more OARs was seen for 89% of the patients, and 44% of the patients had an expected toxicity level decrease.


Asunto(s)
Terapia de Protones , Protones , Humanos , Terapia de Protones/métodos , Incertidumbre , Tomografía Computarizada por Rayos X/métodos , Planificación de la Radioterapia Asistida por Computador/métodos
10.
Int. j. morphol ; 41(3): 733-742, jun. 2023. ilus, tab
Artículo en Español | LILACS | ID: biblio-1514294

RESUMEN

En la última década, la odontología forense se ha enfocado en el desarrollo de metodologías para la estimación de edad (EE) debido a la gran demanda en procesos identificatorios. Entre esas técnicas, el conteo de anulaciones del cemento dental (TCA) ha ofrecido resultados promisorios, pero también contradictorios que han generado dudas sobre su precisión y confiabilidad. El objetivo de este trabajo fue caracterizar, establecer alcances, e identificar las limitaciones del conteo de TCA según los actuales estándares normativos y metodológicos. Se realizó una revisión con búsqueda sistemática del método de conteo de TCA para EE incluyendo estudios experimentales y notas técnicas en las bases PubMed/Medline, Scopus, Web of Science (WoS) y Embase. Se emplearon los términos "estimation", "age" y "cementum", con búsqueda manual complementaria en Google Scholar. Se excluyeron revisiones, estudios en colecciones arqueológicas, estudios radiológicos y cartas al editor. La búsqueda arrojó un total de 273 artículos, seleccionándose 27 que cumplieron con los criterios de inclusión. La mayoría de los estudios fueron publicados en Asia, particularmente en India (n=21). Sólo 6 artículos declararon el número total de individuos, tipos de diente y de cortes histológicos, siendo el premolar el más estudiado. Apenas dos artículos evaluaron la calidad de la muestra a analizar mediante legibilidad de los cortes obtenidos. El test más empleado para evaluar la precisión del método fue el coeficiente de correlación de Pearson (n=21). Estos hallazgos exponen la alta heterogeneidad reportada en las metodologías de EE mediante conteo por TCA, por lo que aún no existe un proceso estandarizado que abarque todas sus etapas y entregue resultados confiables siguiendo los estándares jurídicos actuales para la evidencia científica. Un mayor control de las limitaciones técnicas detectadas aumentará el valor como prueba en un contexto identificatorio legal o forense.


SUMMARY: In the last decade, forensic odontology has focused on the development of age estimation (AE) methodologies due to the great request in identification processes. Among these techniques, the tooth cementum annulation (TCA) count method has offered promising but also contradictory results, raising questions about its accuracy and reliability. The aim of this work was to characterize, establish the scope, and identify the limitations of the TCA count method according to the current normative and methodological standards. A scoping review was carried out for TCA count methods for AE, including experimental studies and technical notes in the PubMed/Medline, Scopus, Web of Science (WoS) and Embase databases. The terms "estimation", "age" and "cementum" were used, with a complementary manual search in Google Scholar. Reviews, studies in archaeological collections, radiological studies and letters to the editor were excluded. The search yielded a total of 273 articles, selecting 27 of them that met the inclusion criteria. Most of the studies were published in Asia, particularly India (n=21). Only 6 articles declared the total number of individuals, types of teeth, and histological sections, with the premolar being the most studied. Only two articles evaluated the quality of the sample to be analyzed through the legibility of the cuts obtained. The most widely used test to assess the precision of the method was the Pearson correlation coefficient (n=21). These findings expose the high heterogeneity reported in EE methodologies by counting TCA, so there is still no standardized process that covers in all its stages and delivers reliable results following current legal standards for scientific evidence. More control of the detected technical limitations will increase the value as evidence in a legal or forensic identification context.


Asunto(s)
Humanos , Determinación de la Edad por los Dientes/métodos , Cemento Dental/anatomía & histología , Odontología Forense
11.
Artículo en Inglés | MEDLINE | ID: mdl-37222903

RESUMEN

Dental age estimation (DAE) is key to establishing an individual's identity, and this is relevant in minors. A widely used method for DAE in children is Cameriere's open apices (CAM). Despite its wide dissemination, there are no clear reports of its use in Latin American populations. A scoping review was conducted using a search strategy in the PubMed/MEDLINE database, Web of Science, and a complementary manual search. Only papers using CAM or its regression equation models for evaluating Latin American populations were included. Ten studies published between 2007 and 2020 responded to the search objective. Brazil was the country with the most studies using CAM (7/10), and the University of Macerata (Italy) was the most declared affiliation (6/10). Seven studies used the original CAM formula in populations from Brazil and Peru, while the European formula (EuCAM) was applied in Mexico, Colombia, and Brazil. Although the method underestimated the age values with acceptable error margins, the correction factor substantially improved the predictive power of the method. Some limitations of the method are highlighted. CAM and its variants can be useful for validation in Latin American settings, but attention to population structures and terminologies is suggested for future research.

12.
Med Phys ; 50(7): 4675-4687, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37194638

RESUMEN

PURPOSE: To provide the first clinical test case for commissioning of 192 Ir brachytherapy model-based dose calculation algorithms (MBDCAs) according to the AAPM TG-186 report workflow. ACQUISITION AND VALIDATION METHODS: A computational patient phantom model was generated from a clinical multi-catheter 192 Ir HDR breast brachytherapy case. Regions of interest (ROIs) were contoured and digitized on the patient CT images and the model was written to a series of DICOM CT images using MATLAB. The model was imported into two commercial treatment planning systems (TPSs) currently incorporating an MBDCA. Identical treatment plans were prepared using a generic 192 Ir HDR source and the TG-43-based algorithm of each TPS. This was followed by dose to medium in medium calculations using the MBDCA option of each TPS. Monte Carlo (MC) simulation was performed in the model using three different codes and information parsed from the treatment plan exported in DICOM radiation therapy (RT) format. Results were found to agree within statistical uncertainty and the dataset with the lowest uncertainty was assigned as the reference MC dose distribution. DATA FORMAT AND USAGE NOTES: The dataset is available online at http://irochouston.mdanderson.org/rpc/BrachySeeds/BrachySeeds/index.html,https://doi.org/10.52519/00005. Files include the treatment plan for each TPS in DICOM RT format, reference MC dose data in RT Dose format, as well as a guide for database users and all files necessary to repeat the MC simulations. POTENTIAL APPLICATIONS: The dataset facilitates the commissioning of brachytherapy MBDCAs using TPS embedded tools and establishes a methodology for the development of future clinical test cases. It is also useful to non-MBDCA adopters for intercomparing MBDCAs and exploring their benefits and limitations, as well as to brachytherapy researchers in need of a dosimetric and/or a DICOM RT information parsing benchmark. Limitations include specificity in terms of radionuclide, source model, clinical scenario, and MBDCA version used for its preparation.


Asunto(s)
Braquiterapia , Humanos , Dosificación Radioterapéutica , Braquiterapia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radiometría , Mama/diagnóstico por imagen , Método de Montecarlo
13.
Artículo en Inglés | MEDLINE | ID: mdl-37178447

RESUMEN

The age estimation (AE) of human remains is a challenging task since it is dependent on the state in which these remains are found. Since the macroscopic evaluation of palatal sutures has been proposed as a method for AE, the aim of this study was to review the literature on this method, considering that the cases of edentulous elderly are among the greatest challenges in anthropological and forensic contexts. A scoping review was performed using a specific search strategy in PubMed, Web of Science, SciELO, LILACS, and Google Scholar. The search identified 13 articles, among which the USA yielded the most information with 3 articles. Only 1 study was identified in Latin America (Peru). There was great diversity regarding the origin of samples, and the studies were carried out on both historical and modern populations. Only 6 articles exceeded the average sample size (168.08) and 4 articles studied samples of fewer than 100 individuals. Although 6 different methods were identified, Mann et al.'s revised method was the most used. The selection of appropriate methods for AE depends on what skeletal elements are present and the general age of the specimens. Although evaluation of the obliteration of the palatal sutures has been found to be simple and promising for AE in individuals over 60 years of age, this method has been reported to have less precision than other more complex methods, which makes the use of a combination of methods necessary to increase the level of confidence and the percentage of success. Further research could resolve this weakness, and methodological refinement (perhaps the digitization and automation of processes, or the application of Bayesian methodology) could provide the necessary solidity to comply with international standards in the forensic scenario.

14.
J Forensic Leg Med ; 96: 102528, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37099885

RESUMEN

Forensic odontology (FO) provides expert testimony; however, new criticism has identified FO as one of the fields that must strengthen its scientific foundations. The recent Netflix documentary titled "The Innocence Files", featuring wrongful convictions, dedicates three of its nine episodes almost exclusively to bite mark identification (BMI), one of the most questioned tests performed by FO. Although most of the FO fields have an undoubted utility in forensic and juridical context, only BMI has been questioned in recent years; the derogatory expression "Junk science" is used continuously in the documentary almost as a synonym for FO. We present a scoping review of cases reported in the US National Registry of Exonerations in which FO was false or misleading forensic evidence (F/MFE) leading to wrongful convictions. Although in the 26 cases identified the only declared F/MFE was the BMI (excluding any other type of dental expertise), only in 2 cases (7.69%) was F/MFE the sole contributing factor, and in 4 cases (15.38%) there was F/MFE plus three additional factors. Official misconduct was detected in 19 cases (73.08%) and perjury or false accusation in 16 cases (61.54%). It has already been mentioned how dangerous it is to consider FO as synonymous with "bite mark identification", or even to publicly provide incorrect or decontextualized information. This review shows that erroneous convictions have been exclusively in the field of BMI, and that FO encompasses much more than just BMI. The relationship between the media and forensic sciences has been strained. The perspective of the new culture of risk management in forensics is also discussed.


Asunto(s)
Mordeduras y Picaduras , Odontología Forense , Humanos , Ciencias Forenses , Medicina Legal , Testimonio de Experto
15.
Int. j. morphol ; 41(2): 451-455, abr. 2023. ilus, tab
Artículo en Español | LILACS | ID: biblio-1440320

RESUMEN

El objetivo de este estudio fue comparar el tiempo empleado al estimar la edad dental (ED) entre el método propuesto por Demirjian et al. y el cuadro integral del enfoque de Demirjian (DAEcc) utilizando radiografías panorámicas digitales de individuos peruanos de 5 a 13 años residentes en Lima. Se realizó un estudio no experimental, comparativo, transversal y retrospectivo. Se utilizaron 100 radiografías panorámicas digitales que presentaban siete dientes permanentes mandibulares izquierdos. Una odontóloga forense capacitada y calibrada determinó el tiempo utilizado en evaluar la maduración dental y la estimación de ED con dos métodos (Demirjian y DAEcc). La unidad de medida utilizada fue los minutos (min.). No hubo diferencias en el tiempo de evaluación del estadio de maduración dental entre ambos métodos (p<0,05). El tiempo para estimar ED fue estadísticamente inferior con DAEcc (2,09 min) que con Demirjian (4,19 min). La diferencia del tiempo total de evaluación resultó estadísticamente significativa entre ambos métodos (Δ2,1 min.; 2,05-2,11; p=0,000). La aplicación del DAEcc redujo en 50 % el tiempo empleado en estimar ED en comparación con los cuadros propuestos por Demirjian. Aunque la odontología forense se centra en el estudio de la eficacia de estimación de la edad, es necesario abordar también su uso práctico.


SUMMARY: The objective of this study was to compare the time used to estimate dental age (DA) between the method proposed by Demirjian et al., and the comprehensive chart for dental age estimation (DAEcc) using digital panoramic radiographs of Peruvian individuals aged 5 to 13 years residing in Lima. A non- experimental, comparative, cross-sectional and retrospective study was carried out. 100 digital panoramic radiographs showing seven mandibular left permanent teeth were used. A trained and calibrated forensic odontologist determined the time used to assess tooth maturation and DA estimation with two methods (Demirjian and DAEcc). The unit of measurement used was minutes (min.). There were no differences in the evaluation time of the dental maturation stage between both methods (p<0.05). The time spent to estimate DA was statistically less with DAEcc (2.09 min) than with Demirjian (4.19 min). The difference in total evaluation time was statistically significant between both methods (Δ2.1 min; 2.05-2.11; p=0.000).The application of DAEcc reduced by 50 % the time spent estimating DA compared to the method proposed by Demirjian. Although forensic odontology focuses on the study of the effectiveness of age estimation, its practical use needs to be addressed as well.


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Adolescente , Diente/diagnóstico por imagen , Determinación de la Edad por los Dientes/métodos , Odontología Forense , Perú , Factores de Tiempo , Diente/crecimiento & desarrollo , Radiografía Panorámica , Proyectos Piloto , Estudios Transversales , Estudios Retrospectivos
16.
Brachytherapy ; 22(2): 269-278, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36631373

RESUMEN

PURPOSE: Even though High Dose Rate (HDR) brachytherapy has good treatment outcomes in different treatment sites, treatment verification is far from widely implemented because of a lack of easily available solutions. Previously it has been shown that an imaging panel (IP) near the patient can be used to determine treatment parameters such as the dwell time and source positions in a single material pelvic phantom. In this study we will use a heterogeneous head phantom to test this IP approach, and simulate common treatment errors to assess the sensitivity and specificity of the error-detecting capabilities of the IP. METHODS AND MATERIALS: A heterogeneous head-phantom consisting of soft tissue and bone equivalent materials was 3D-printed to simulate a base of tongue treatment. An High Dose Rate treatment plan with 3 different catheters was used to simulate a treatment delivery, using dwell times ranging from 0.3 s to 4 s and inter-dwell distances of 2 mm. The IP was used to measure dwell times, positions and detect simulated errors. Measured dwell times and positions were used to calculate the delivered dose. RESULTS: Dwell times could be determined within 0.1 s. Source positions were measured with submillimeter accuracy in the plane of the IP, and average distance accuracy of 1.7 mm in three dimensions. All simulated treatment errors (catheter swap, catheter shift, afterloader errors) were detected. Dose calculations show slightly different distributions with the measured dwell positions and dwell times (gamma pass rate for 1 mm/1% of 96.5%). CONCLUSIONS: Using an IP, it was possible to verify the treatment in a realistic heterogeneous phantom and detect certain treatment errors.


Asunto(s)
Braquiterapia , Humanos , Dosificación Radioterapéutica , Braquiterapia/métodos , Diseño de Equipo , Fantasmas de Imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Impresión Tridimensional
17.
Eur J Dent Educ ; 27(2): 240-251, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35290698

RESUMEN

BACKGROUND: A mass fatality incident is an unexpected event that can cause the death of many people, which has motivated careful analysis and development of appropriate strategies for planning and response with all available resources. As these events involve multiple victims, their identities must be confirmed using the highest possible quality standards. Forensic Odontology (FO) has proven to be a scientific resource for disaster victim identification (DVI) procedures; however, it is highly dependent on the proper management not only of material resources but also of human resources. Chile is a country recognised as prone to natural disasters, but an insufficient number of forensic odontologists has been reported. The aim of the study was to review the literature on a dental undergraduate (UG) student's potential value in a DVI process. METHODOLOGY: A scoping review was performed using a specific search strategy in PubMed/Medline, Web of Science, Scopus, SciELO and EBSCO databases. RESULTS: The search identified 27 articles in which the basic dental degree, the necessary training and the need for human resources are variables considered in different priorities by those articles. DISCUSSION: It is vital to assess the local needs of Chile based on its UGs, considering that FO is an underestimated resource that should be included early on in dental curriculums. Furthermore, it should align with public policies to ensure viability and inclusion in standardised protocols. CONCLUSION: Although there is "potential" usage of UG dental students in DVI is not ideal, circumstances will dictate their use. The better trained they are as students, the more valuable their "potential" contribution will be.


Asunto(s)
Víctimas de Desastres , Odontología Forense , Humanos , Chile , Odontología Forense/métodos , Estudiantes de Odontología , Educación en Odontología
18.
Forensic Sci Med Pathol ; 19(2): 224-235, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35781622

RESUMEN

Dental age estimation (DAE) is one of the most reliable and useful scientific methods employed by forensic odontology (FO) for human identification. In 2009, the US National Academy of Sciences (NAS) report highlighted the need to deepen research in many disciplines, among which FO received strong criticism for specific expertise. The aim of this review is to provide a comprehensive overview in order to systematically map the latest original research done in FO, as well as identify DAE within this field. A systematic search was performed from 2014 to 2019. In total, 644 studies were identified for qualitative analysis: DAE was the most studied topic (41.30%). Asia was the most productive continent with 58.27% of the global production on DAE; India was the most productive Asian country, with 32.33% and 55.48% of global and Asian production, respectively. The University of Macerata (Italy), KU Leuven (Belgium), University of Split (Croatia), and University of São Paulo (Brazil) led DAE research. Authors from leading countries on DAE research demonstrated great individual productivity, which is evidence of their scientific efforts, but also possible risks if the continuity of this line of research depends on them. Although FO has significantly focused its research on DAE, the absence of publications on controversial topics but necessary for research according to the NAS report shows the possible lack of interest of authors or journals to address them.


Asunto(s)
Odontología Forense , Ciencias Forenses , Humanos , Odontología Forense/métodos , Antropología Forense/métodos , Medicina Legal
19.
Forensic Sci Med Pathol ; 19(1): 16-23, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35763190

RESUMEN

Although there are physiological methods to determine the postmortem interval (PMI), interval forensic histopathology can be applied to obtain accuracy. The aim was to describe the histological changes in human lingual striated musculature at different PMI. Seven groups were formed according to increasing PMI of 6, 12, 24, 48, 72, 96 and 120 h postmortem (PM). Each group was made up of 16 samples of tongues from each cadaver. The samples were fixed in buffered formaldehyde at 10% and processed for embedding in paraplast. Section 5 µm thick were cut and dyed with H&E for analysis. The study was approved by the Bioethics Committee of the Universidad San Francisco de Quito, Ecuador. The histological changes in the striated muscle cells of the tongue were associated with the different PMI. From 6 to 24 h PM, there were initial changes in the cellular and nuclear morphology. At 48 h PM, at least 50% of the samples presented poorly conserved and reduced muscle striations. At 72 h PM, 100% of the cases presented myofibers with altered morphology, cytoplasmic vacuoles (93.75%), edema (68.55%) and pyknosis (93.75%). At 96 and 120 h PM, the myofibers presented pyknotic nuclei, and they were absent in the rest. The changes in the histology of the human lingual striated muscle make it possible to estimate the PMI, either in the early phase (0-72 h) or the late phase (92-120 h). However, further research is needed to verify, refine and expand on these results.


Asunto(s)
Músculo Esquelético , Cambios Post Mortem , Humanos , Cadáver , Autopsia , Lengua
20.
Phys Med Biol ; 68(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36584391

RESUMEN

Objective. There is a continuous increase in 3D printing applications in several fields including medical imaging and radiotherapy. Although there are numerous advantages of using 3D printing for the development of customized phantoms, bolus, quality assurance devices and other clinical applications, material properties are not well known and printer settings can affect considerably the properties (e.g. density, isotropy and homogeneity) of the printed parts. This study aims to evaluate several materials and printer properties to identify a range of tissue-mimicking materials.Approach. Dual-energy CT was used to obtain the effective atomic number (Zeff) and relative electron density (RED) for thirty-one different materials including different colours of the same filament from the same manufacturer and the same type of filament from different manufacturers. In addition, a custom bone equivalent filament was developed and evaluated since a high-density filament with a composition similar to bone is not commercially available. Printing settings such as infill density, infill pattern, layer height and nozzle size were also evaluated.Main results. Large differences were observed for HU (288), RED (>10%) andZeff(>50%) for different colours of the same filament due to the colour pigment. Results show a wide HU variation (-714 to 1104), RED (0.277 to 1.480) andZeff(5.22 to 12.39) between the printed samples with some materials being comparable to commercial tissue-mimicking materials and good substitutes to a range of materials from lung to bone. Printer settings can result in directional dependency and significantly affect the homogeneity of the samples.Significance. The use of DECT to extract RED, andZeffallows for quantitative imaging and dosimetry using 3D printed materials equivalent to certified tissue-mimicking tissues.


Asunto(s)
Oncología por Radiación , Radiometría , Radiografía , Fantasmas de Imagen , Impresión Tridimensional , Tomografía Computarizada por Rayos X
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