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1.
Int J Legal Med ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856752

RESUMEN

Investigation of the biological sex of human remains is a crucial aspect of physical anthropology. However, due to varying states of skeletal preservation, multiple approaches and structures of interest need to be explored. This research aims to investigate the potential use of distances between bifrontal breadth (FMB), infraorbital foramina distance (IOD), nasal breadth (NLB), inter-canine width (ICD), and distance between mental foramina (MFD) for combined sex prediction through traditional statistical methods and through open-access machine-learning tools. Ethical approval was obtained from the ethics committee, and out of 100 cone beam computed tomography (CBCT) scans, 54 individuals were selected with all the points visible. Ten extra exams were chosen to test the predictors developed from the learning sample. Descriptive analysis of measurements, standard deviation, and standard error were obtained. T-student and Mann-Whitney tests were utilized to assess the sex differences within the variables. A logistic regression equation was developed and tested for the investigation of the biological sex as well as decision trees, random forest, and artificial neural networks machine-learning models. The results indicate a strong correlation between the measurements and the sex of individuals. When combined, the measurements were able to predict sex using a regression formula or machine learning based models which can be exported and added to software or webpages. Considering the methods, the estimations showed an accuracy rate superior to 80% for males and 82% for females. All skulls in the test sample were accurately predicted by both statistical and machine-learning models. This exploratory study successfully established a correlation between facial measurements and the sex of individuals, validating the prediction potential of machine learning, augmenting the investigative tools available to experts with a high differentiation potential.

2.
J Prosthet Dent ; 118(2): 235-241, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28159348

RESUMEN

STATEMENT OF PROBLEM: The longevity of silicone facial prostheses is short, and published data concerning this type of rehabilitation are limited. PURPOSE: The purpose of this retrospective study was to identify predictive variables for prosthetic failure and to highlight the results that can be expected after treatment with silicone facial prostheses. MATERIAL AND METHODS: After institutional approval, patient records from a single Brazilian institution for the time period 2004 to 2015 were assessed. A standardized form was used to collect patient data. Frailty survival modeling (simple random effects survival model) was used to test whether age, sex, type of prosthesis, source of defect, number of implants, and type of retention have a direct impact on the prosthetic failure rate (α=.05). RESULTS: Auricular prostheses were the most frequently fabricated prostheses. Eighty-four prostheses were fabricated during the follow-up period. The overall survival rate for facial prostheses was 34.5%. Color alteration was the most common reason for new prostheses (27.38%). The implant success rate was 98.18%. The number of implants approached statistical significance (P=.06) with a reduced risk of failure when the patient had 2 implants compared with patients with zero implants and patients with more than 2 implants. CONCLUSIONS: Patients should be recalled frequently so that retouches can be performed, avoiding the repeated fabrication of new prostheses. Well-designed studies are necessary to identify more relevant complications and factors that lead to prosthetic failure.


Asunto(s)
Cara/cirugía , Complicaciones Posoperatorias/epidemiología , Prótesis e Implantes , Cráneo/cirugía , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Falla de Prótesis , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
3.
Sci Rep ; 14(1): 369, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172136

RESUMEN

The process of creating virtual models of dentomaxillofacial structures through three-dimensional segmentation is a crucial component of most digital dental workflows. This process is typically performed using manual or semi-automated approaches, which can be time-consuming and subject to observer bias. The aim of this study was to train and assess the performance of a convolutional neural network (CNN)-based online cloud platform for automated segmentation of maxillary impacted canine on CBCT image. A total of 100 CBCT images with maxillary canine impactions were randomly allocated into two groups: a training set (n = 50) and a testing set (n = 50). The training set was used to train the CNN model and the testing set was employed to evaluate the model performance. Both tasks were performed on an online cloud-based platform, 'Virtual patient creator' (Relu, Leuven, Belgium). The performance was assessed using voxel- and surface-based comparison between automated and semi-automated ground truth segmentations. In addition, the time required for segmentation was also calculated. The automated tool showed high performance for segmenting impacted canines with a dice similarity coefficient of 0.99 ± 0.02. Moreover, it was 24 times faster than semi-automated approach. The proposed CNN model achieved fast, consistent, and precise segmentation of maxillary impacted canines.


Asunto(s)
Aprendizaje Profundo , Diente Impactado , Humanos , Tomografía Computarizada de Haz Cónico/métodos , Diente Canino/diagnóstico por imagen , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador/métodos
4.
Artículo en Inglés | MEDLINE | ID: mdl-38493025

RESUMEN

OBJECTIVE: To assess the efficacy of the metal artifact reduction algorithm (MARA) of the Cranex 3D cone beam computed tomography (CBCT) device in the detection of peri-implant dehiscence and fenestration around zirconia implants. STUDY DESIGN: In total, 60 implants were placed in bovine ribs. Dehiscence and fenestration defects were created around the implants, after which 60 CBCT images were obtained with and 60 without activation of MARA. Three radiologists examined the images for the presence of defects. The area under the curve (AUC) from receiver operating characteristic analysis, sensitivity, and specificity were calculated to assess the ability to discriminate the presence vs absence of bone defects. One-way analysis of variance was employed to analyze outcome measures. The significance level was established at 5% (α = 0.05). RESULTS: AUC values indicated excellent discrimination of dehiscence on images with MARA activation and an excellent to outstanding range of discrimination with MARA deactivation. For fenestration, MARA activation and deactivation both led to outstanding discrimination. Sensitivity and specificity values revealed that activation of MARA was helpful in distinguishing the presence vs. absence of dehiscence, while both MARA conditions were helpful for fenestration. However, there were no statistically significant differences between MARA activation and deactivation for any outcome measure (P >.05). CONCLUSION: CBCT is suitable for detecting peri-implant defects, but MARA application does not significantly affect peri-implant dehiscence and fenestration detection.

5.
J Vet Dent ; 40(2): 134-142, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36482686

RESUMEN

The articular surfaces of the temporomandibular joint (TMJ) in the cat consist of the articular head of the condylar process of the ramus of the mandible and the mandibular fossa of the petrous part of the temporal bone. Anatomic conformation of the TMJ articular surfaces can vary; however, this has not been studied in the cat. Thus, the aim of this study was to characterize the conformation of the medial region of the TMJ in mesocephalic adult cats as well as to determine the articular relationship by measurement of the degree of coverage of the mandibular fossa over the articular head. This was accomplished by assessing 60 TMJs from 30 mesocephalic adult cats by means of cone-beam computed tomography (CBCT). The width and depth of the mandibular fossa, and the degree of coverage of the mandibular fossa were evaluated using parasagittal reconstructions of the medial aspect of the TMJ by two observers. No statistically significant difference was observed during the intra and interobserver evaluation of the mandibular fossa width and depth and the degree of coverage of the mandibular fossa over the articular head. P-values for the studied variables were greater than 0.05. The resulting measurements demonstrated a concave mandibular fossa with a prominent retroarticular process and a poorly developed articular eminence; a well-defined rounded articular surface, and a high degree of coverage (171°) of the mandibular fossa over the articular head. In conclusion, the articular surfaces at the medial aspect of the TMJ displayed elevated geometric similarity, with an articular head of the condylar process deeply seated in the mandibular fossa.


Asunto(s)
Enfermedades de los Gatos , Trastornos de la Articulación Temporomandibular , Gatos , Animales , Articulación Temporomandibular/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/veterinaria , Mandíbula , Trastornos de la Articulación Temporomandibular/veterinaria , Hueso Temporal , Enfermedades de los Gatos/diagnóstico por imagen
6.
Iran Endod J ; 18(4): 211-217, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37829825

RESUMEN

Introduction: This study aimed to evaluate if the apical patency can influence the adaptation of the master cone of gutta-percha, quantifying the volume of voids and areas at the last 2 mm of the working length (WL). Materials and Methods: Sixty distobuccal canals of extracted upper molars were divided into 3 groups (n=20) based on the patency length (A: passed 1 mm beyond the apical foramen (AF), B: at the AF and C: 1 mm short of the AF) with the Easy ProDesign Logic 25/0.01 file. Each group was subdivided into 2 subgroups (n=10) based on the WL established to prepare the root canal (1: 1 mm short of the AF or 2: at the AF) with the Easy ProDesign Logic 25/0.05 file. After the scan, void volumes were calculated from the last 2 mm of the WL and void areas at 0 mm, 1 mm and 2 mm of the last of WL, as well as the relation between the tip and taper of the master cone with the amount of void volume and areas. To investigate statistically significant differences, we used the Kruskal-Wallis statistical test. Results: There were more voids in volume when patency was achieved 1 mm beyond the AF and the root canal preparation was conducted at 1mm short of the AF (A1 group). Furthermore, the same group showed more voids areas, mainly on the last millimeter of WL. Conclusion: Achieving apical patency at 1 mm beyond the AF followed by instrumentation 1 mm short of the AF created more voids between the master gutta-percha cone and the root canal wall, especially on the last millimeter of WL.

7.
Clin Oral Implants Res ; 23(7): 797-804, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21631591

RESUMEN

PURPOSE: The aim of this study was to evaluate the accuracy of cone-beam computed tomography (CBCT) for measuring the buccal bone volume around dental implants. MATERIALS AND METHODS: Three to six implants were inserted into the anterior maxilla of eight skulls, depending on the availability of bone, and after this, the CBCT was performed. By means of CBCT image, measurements of the bone wall at three points of the implant were obtained, analyzed and compared with those obtained in the plaster skull casting. RESULTS: The results showed that for the three points of the implants, no statistically significant difference in the measurements was obtained from the plaster model and CBCT images. CONCLUSIONS: CBCT can be a useful tool for assessing buccal bone volume along the implant.


Asunto(s)
Proceso Alveolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Implantes Dentales , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Proceso Alveolar/anatomía & histología , Análisis de Varianza , Cadáver , Técnica de Impresión Dental , Humanos , Procesamiento de Imagen Asistido por Computador
8.
J Oral Maxillofac Surg ; 70(7): 1534-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22079066

RESUMEN

PURPOSE: To compare 2 methods used to determine the disk position based on sagittal magnetic resonance images. PATIENTS AND METHODS: A cross-sectional study of patients with the signs and symptoms of temporomandibular disorders was conducted. The patients' ages and gender distributions were collected. The disk position diagnosis from the clinical examination was considered the primary outcome. Three observers evaluated the presence of anterior displacement on magnetic resonance images according to 2 criteria: method 1 (12-o'clock position) and method 2 (location of the intermediate zone). To assess the intraobserver variability of the 2 methods, the examiners evaluated the same magnetic resonance images at the beginning of the study (time 1) and 40 days later (time 2). The intraobserver agreement was assessed using the observed agreement and the kappa statistic. McNemar's test was used to assess the differences between each method and the clinical examination findings (P < .05). The accuracy, sensitivity, specificity, and positive and negative predictive values were calculated by comparing the diagnosis from each method with that from the clinical examination (considered the reference standard). RESULTS: The final sample was composed of 20 subjects with a mean age of 33.0 ± 33.7 years; 3 were men (15%) and 17 were women (85%). A statistically significant difference between the 2 methods was found. Method 1 yielded a greater percentage of anterior displaced disks (52.5%). The agreement between the clinical diagnosis and method 1 was lower (70.0%) than that between the clinical diagnosis and method 2 (87.5%). No statistically significant difference was found between the clinical diagnosis and method 2. CONCLUSION: The disk position should be judged according to the intermediate zone criterion.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Disco de la Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/patología , Articulación Temporomandibular/patología , Adulto , Artralgia/patología , Estudios Transversales , Reacciones Falso Positivas , Femenino , Estudios de Seguimiento , Humanos , Luxaciones Articulares/patología , Masculino , Cóndilo Mandibular/patología , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Rango del Movimiento Articular/fisiología , Sensibilidad y Especificidad , Sonido
9.
Iran Endod J ; 16(1): 56-59, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36704410

RESUMEN

Guided endodontic access is a promising method to treat teeth with pulp calcification. This report aimed to describe a case of root canal treatment performed through guided endodontic access in a calcified anterior tooth with apical periodontitis. A 23-year-old female with a history of trauma 10 years ago in the anterior maxilla was referred to the dental office. Her chief complaint was discolouration of the left central incisor crown. The tooth was sensitive to percussion and responded negatively to pulp sensitivity tests. The periapical radiography showed pulp calcification and periapical radiolucency. Cone-beam computed tomography (CBCT) was obtained to allow a more detailed view of the pulp canal and the periapical area. An intraoral scan was performed and the standard tessellation language (STL) archive was combined with digital imaging and communications on medicine (DICOM) images from CBCT in the Implant Viewer software. Subsequently, a 3D model was designed and printed to guide the endodontic access in position and appropriate angulation for dental instrumentation. The mold was positioned on the patient's tooth and the root canal treatment was performed. After two years, complete healing of periapical tissues was observed. This method facilitates the drill targeting during access, reducing the risk of deviations and perforations.

10.
Leg Med (Tokyo) ; 50: 101866, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33667933

RESUMEN

Forensic facial reconstruction (approximation) (FFR) is an aid to human identification when no presumed identity is available. It is based on average soft tissue thickness (STT) applied onto a skull. These averages vary at each landmark according to sex, ancestry, and Facial Growth Patterns (FGP). To obtain the reference, there are different protocols and conditions, such as needles in cadavers, ultrasound, magnetic resonance, and computer tomography. Using cone-beam computed tomography (CBCT), landmark placement and direction of measurement are critical. The purpose of this article is to detailly describe a method for STT measurement in CBCT DICOM files and to test it in the analysis of a multi-ancestral Brazilian sample, subdivided into sex, age and FGP. A sample of 100 (50 male and 50 female) CBCT exams were selected and the volume was primarily been repositioned to cephalometric standards. A detailed description of the location and measurement direction of 32 landmarks was provided and granted good reproducibility of the measurements. The averages were assessed by sex, age, and FGP. There were significant differences between males and females. The CBCT measuring protocol provided standardization of measurements and is a method to be used in future researches. Advantages of CBCT, such as the subject's upright position and adjustable volume positioning, also justify its usage. Limited differences of STT were related to age and FGP. The updated Brazilian soft tissue thickness chart is a reliable source of data for forensic and clinical purposes.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Cefalometría , Femenino , Antropología Forense , Humanos , Imagenología Tridimensional , Masculino , Reproducibilidad de los Resultados
11.
Dentomaxillofac Radiol ; 49(6): 20190396, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32364770

RESUMEN

OBJECTIVE: This research aimed to longitudinally evaluate the optical density of peri-implant alveolar bone. The data acquired from study participants previously treated with 37 osseointegrated implants were analyzed utilizing the radiographic subtraction technique. METHODS AND MATERIALS: The radiographic follow-ups were performed five times: at the implantation of the prostheses and after 15, 90, 180 and 360 days. Intraoral radiographs were obtained by the paralleling technique using individualized Hanshin-type positioners to guarantee the standardization of the images. The obtained digital images were aligned and equalized before they were submitted to the radiographic subtraction procedure. RESULTS: A significant difference was found between the distal region of Group I (patients treated with osseointegrated implants who required extraction of the dental element) and the 360 day follow-up and the distal region of Group II (patients with healed alveolar sockets) in all follow-up analyses (p < 0.05). We did not observe a significant difference between the groups analyzed and other follow-ups concerning the subcrestal and middle third regions for both the mesial and distal variables (p > 0.05). There was a statistically significant difference in the distal sites [χ2 = 5,745,, p = 0.03], showing a significant association between time and the presence of bone resorption. This association was not shown on the mesial surface (p = 0.16). CONCLUSION: We concluded that there was no statistically significant difference between groups I and II. Using this technique, we were able to quantitatively and qualitatively evaluate the changes in the proximal sites on the digital radiographic images for the analyzed data. Digital subtraction technology to measure peri-implant bone density is an accurate and reproducible technique for quantifying peri-implant bone reactions to different therapeutic modalities.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico por imagen , Implantes Dentales , Implantación Dental Endoósea , Estudios de Seguimiento , Humanos , Maxilar/diagnóstico por imagen , Radiografía Dental Digital , Técnica de Sustracción
12.
J Forensic Sci ; 63(3): 692-698, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28731499

RESUMEN

Few studies have assessed the use of the frontal sinus cavities for sex differentiation. In this study, a new methodology was used to assess the reliability of CBCT images of the frontal sinus cavity for determining sex based on the sexual dimorphism found in this anatomical structure. The survey sample consisted of 130 scans that were reconstructed three-dimensionally. 3D images of the cavity volume in the frontal, lateral, and basal views were exported in TIFF. The following variables were measured in a second program: area, perimeter, bounding rectangle, ellipse fit, circularity, aspect ratio, roundness, solidity, and Feret's diameter. The methodology demonstrated the existence of sexual dimorphism with an accuracy of 80.0% in the logistic regression model. The basal view had the greatest explanatory power in the final model. This methodology may be used as an alternative way of determining a reliable biological profile during the analysis of skeletal remains.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Seno Frontal/anatomía & histología , Seno Frontal/diagnóstico por imagen , Imagenología Tridimensional , Determinación del Sexo por el Esqueleto/métodos , Adulto , Anciano , Femenino , Antropología Forense , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Adulto Joven
13.
Acta Cir Bras ; 22(5): 387-95, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17923960

RESUMEN

PURPOSE: To evaluate the rehabilitation of edentulous mandibles with osseous integrated implants in immediate loading, using models in reverse planning. METHODS: A prospective study was performed on 14 patients with a total of 56 implants placed. It was proposed a technique for the rehabilitation of edentulous mandible with osseous integrated implants of immediate loading, using anatomical replicas derived from computerized tomography scan linked to the rapid prototyping technique of stereolithography in reverse planning, elaborating the definitive fixed prosthesis, with rigid union of the implants on the same day. The patients' mandible models were divided in two groups. In the first one, there were patients with edentulous mandible models and with models elaborated after exodontics procedures (Group 1). In the second (Group 2), patients with dentulous mandible models, which allow an evaluation of difficulty in the surgery. RESULTS: The proposed technique using anatomical models for the personalization of mandibles in immediate loading had 100% of less difficulty in the adaptation of the surgery guide while the dentulous models had 83,3% of more difficulty. CONCLUSION: The proposed technique using the mandible models in the rehabilitation of mandibles is feasible.


Asunto(s)
Diseño Asistido por Computadora , Implantación Dental Endoósea/métodos , Arcada Edéntula/rehabilitación , Mandíbula/cirugía , Modelos Anatómicos , Adulto , Anciano , Anciano de 80 o más Años , Interpretación Estadística de Datos , Femenino , Humanos , Arcada Edéntula/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
14.
Braz. j. oral sci ; 21jan.-dez. 2022. ilus
Artículo en Inglés | LILACS, BBO - odontología (Brasil) | ID: biblio-1354779

RESUMEN

Aim: To describe cone-beam computed tomography (CBCT) features in patients with temporomandibular disorders (TMDs), in terms of degenerative changes, condylar excursions and positioning as well as their possible correlations with signs and symptoms. Methods: Clinical records of patients diagnosed with TMD who were seen between January 2018 and December 2019 were retrospectively evaluated. These patients were divided into the following groups based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD): arthralgia, myalgia, and arthralgia and myalgia groups. The CBCT examination findings of the patients were evaluated in relation to degenerative changes, estimates of condylar excursion, and condylar positioning. The likelihood ratio test was used to verify the possible differences among the three groups, whereas the chi-square test was used to verify the possible differences among the signs and symptoms for the tomographic findings (p ≤ 0.050). Results: In this study, 65 patients with TMD were included. These patients were predominantly female (84.6%) with a mean age of 40.6 years. Tomographic findings of flattening, hyperexcursion and posterior condylar positioning were frequent. A significant correlation was noted between osteophyte and lateral capsule pain (p = 0.027), erosion and posterior capsule pain (p = 0.026), and flattening, pseudocysts (p < 0.050) and condylar excursion (p < 0.001) with mouth opening. Conclusion: Few correlations were noted between degenerative changes and signs of joint pain as well as degenerative changes and condylar hypoexcursion with mouth opening. These correlations were likely associated with division by diagnosis, whereas condylar positioning did not correlate with signs and symptoms


Asunto(s)
Signos y Síntomas , Trastornos de la Articulación Temporomandibular , Tomografía Computarizada de Haz Cónico , Cóndilo Mandibular
15.
Forensic Sci Int ; 271: 68-74, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28068573

RESUMEN

Human identification requires comparison of individual traits of a person, depending on the availability and reproduction of antemortem (AM) records. If there is no presumed identity or AM exams are not available for comparison, the production of postmortem (PM) records is impaired. The purpose of this research is to describe and test standards to enable the comparison of antemortem periapical radiographs to images extracted from the manipulation of postmortem CBCT exams in multiple identification simulations in a randomized blind study. In a simulation, 20 CBCT images from dry skulls were used as PM records and 3 periapical radiographs (total of 60) that were randomized and blinded from the first examiner. In each case, an intentional incidence error of 10° was added in four different directions. Three points were selected in the AM radiograph, and the angle, linear measurements and proportion between these distances were collected. The AM data were used to mathematically find similar image geometry on a CBCT maximum intensity projection. Possible identification by superimposition was achieved in all cases, and statistical analysis proved the success in the reproduction of angular and length proportion using CBCT incidence manipulation. Significant reproducibility was also observed on intra- and inter-observer tests. In conclusion, the images extracted from CBCT could be compared to any periapical radiographs by superimposition, providing acceptable evidence to establish human identification. The application of this protocol is suitable for forensic practices with the high level of reproducibility and could be used as PM record when no AM records are available at the time of the exam.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Odontología Forense/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Radiografía Dental Digital , Humanos , Distribución Aleatoria , Reproducibilidad de los Resultados
16.
Braz. dent. sci ; 25(4): 1-14, 2022. tab, ilus
Artículo en Inglés | LILACS, BBO - odontología (Brasil) | ID: biblio-1410422

RESUMEN

Objective: it is important to know the thicknesses of the alveolar bone plates (ABPs) based on the current literature for the planning and success of orthodontic treatment. However, studies have scientific limitations regarding ABPs as the image resolution is not adequate and is restricted to a few teeth or buccal face only. This study was aimed at reporting a reference standard for bone plates of upper teeth, in which 15 patients (mean age of 21.79 years) with balanced occlusion and a harmonious facial profile were evaluated using cone-beam computed tomography at a voxel size of 0.1 mm. Material and Methods: bone tissues of the cervical, middle, and apical thirds of the root (buccal and palatal), the distance between cement-enamel junction (CEJ) and alveolar bone crest (ABC), and inclination of the teeth to the palatal plane were evaluated. Paired t-test, Spearman's correlation tests, and linear regression tests were used (P < 0.05). Results: the buccal distance between the CEJ and ABC was greater than the palatal one in all pairs of teeth. Most of the bone tissues had a thickness ≤ 1 mm in the buccal face, whereas in the cervical-apical direction, the thickness was ≥ 2 mm. There is no equivalence between genders in the sample. Conclusion: the reduced buccal bone architecture around the first premolars was indicative of local gingival recessions, and the lack of gender uniformity was suggestive of individual evaluation. References of normal bone tissue determining the orthodontic limits were provided to assist in the treatment planning. (AU)


Objetivo: é importante conhecer as espessuras das cristas ósseas alveolares (COAs) com base na literatura atual para o planejamento e sucesso do tratamento ortodôntico. No entanto, os estudos apresentam limitações científicas em relação às COAs, pois a resolução da imagem não é adequada e está restrita apenas a alguns dentes ou face vestibular. Este estudo teve como objetivo descrever um padrão de referência para corticais ósseas de dentes superiores, no qual 15 pacientes (idade média de 21,79 anos) com oclusão equilibrada e perfil facial harmonioso foram avaliados por meio de tomografia computadorizada de feixe cônico no tamanho de voxel de 0,1 mm. Material e Métodos: os tecidos ósseos dos terços cervical, médio e apical da raiz (vestibular e palatina), a distância entre a junção cemento-esmalte (JCE) e a crista óssea alveolar (COA) e a inclinação dos dentes ao plano palatino foram avaliados. Foram utilizados o teste t pareado, os testes de correlação de Spearman e os testes de regressão linear (P < 0,05). Resultados: a distância vestibular entre a JEC e a COA foi maior que a palatina em todos os pares de dentes. A maioria dos tecidos ósseos apresentou espessura ≤ 1 mm na face vestibular, enquanto no sentido cérvico-apical a espessura foi ≥ 2 mm. Não há equivalência entre os gêneros na amostra. Conclusão: a arquitetura óssea vestibular reduzida ao redor dos primeiros pré-molares foi indicativa de recessões gengivais locais, e a falta de uniformidade de gênero foi sugestiva de avaliação individual. Referências de tecido ósseo normal determinando os limites ortodônticos foram fornecidas para auxiliar no planejamento do tratamento. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Ortodoncia , Huesos , Tomografía Computarizada de Haz Cónico , Proceso Alveolar , Diagnóstico
17.
J Dent Child (Chic) ; 73(3): 140-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17367030

RESUMEN

PURPOSE: The purpose of this study was to assess, by panoramic radiographs, the prevalence of morphological dental changes in children with cancer who were submitted for chemotherapy alone or concomitant radiotherapy of the head and neck. METHODS: All patients admitted between March, 1996 and February, 2004 were analyzed and 137 were included in this retrospective, nonrandomized, institutional study. The rates of microdontia, taurodontia, anodontia, macrodontia, blunt root, and tapered root were assessed. RESULTS: The patients were distributed into 2 groups: (1) those with lymphoproliferative neoplasias (61%); and (2) those with solid tumors (39%). Their mean age when treatment began was 5 years and 6 months. Dental abnormalities were found in 39 (29%) patients, while 98 (72%) patients did not present any abnormality. The abnormalities found were: (1) microdontia (7%; N= 10); (2) anodontia (6%; N=8); (3) taurodontia (14%; N=19); (4) macrodontia (5%; N=7); (5) blunted root (2%; N=2); and (6) tapered root (4%; N=5). Of these patients: 22% (N=30) presented 1 abnormality; 4% (N=6) presented 2 abnormalities; and 2% (N=3) presented 3 abnormalities. CONCLUSION: Taurodontia was the most frequent abnormality found in children and adolescents who underwent antineoplastic treatment, and its rate was significantly higher than those found for the healthy Brazilian population. This study's results show that it is necessary for the odontologist to systematically research the dental changes that occur among this special group of patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anomalías Dentarias/epidemiología , Adolescente , Factores de Edad , Anodoncia/epidemiología , Brasil/epidemiología , Niño , Preescolar , Cavidad Pulpar/anomalías , Femenino , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Lactante , Leucemia/tratamiento farmacológico , Leucemia/radioterapia , Linfoma/tratamiento farmacológico , Linfoma/radioterapia , Masculino , Radiografía Panorámica , Radioterapia Adyuvante , Estudios Retrospectivos , Raíz del Diente/anomalías
18.
Clin Implant Dent Relat Res ; 18(1): 40-50, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24909241

RESUMEN

PURPOSE: The aim of this prospective clinical study was to evaluate the clinical and histomorphometric data of newly formed bone tissue from fresh frozen human allograft in sinus lift surgery. PATIENTS AND METHODS: Thirty-three sinus lift procedures were performed in 20 patients, divided into two groups. The control group (n = 8) received autogenous bone from the mandibular ramus, and the experimental group (n = 12) received fresh frozen bone (FFB) allograft in chips. After 6 months, 52 implants were placed and 50 biopsies were collected for histomorphometric analysis. Cone beam computed tomography scans were performed at preoperative, immediate postoperative, and delayed postoperative time intervals to assess the degree of graft volume loss. RESULTS: There was no statistically significant difference between groups as regards degree of graft volume loss (p = .983), total bone area (p = .191), remaining particles (p = .348), and proportion of active osteoblasts (p = .867). There was a statistically significant difference in the vitality rate between the groups (p = .043). In both groups, all implants were clinically osseointegrated after 4 months. CONCLUSION: FFB allograft was shown to be a feasible substitute for autogenous bone graft in sinus lift surgery.


Asunto(s)
Trasplante Óseo/métodos , Elevación del Piso del Seno Maxilar/métodos , Adulto , Anciano , Aloinjertos , Biopsia , Brasil , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Mandíbula/trasplante , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
19.
Braz J Otorhinolaryngol ; 71(5): 676-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16612531

RESUMEN

AIM: The aim of this study is to assess and locate the Foramen of Huschke. STUDY DESIGN: Anatomical. MATERIAL AND METHOD: Using contrast material like gutta-percha and barium sulfate, through extraoral radiographs, such as panoramic, submental vertex and corrected sagittal linear Temporal Mandibular Joint tomograms in four skulls where we clinically checked the existence of foramen of Huschke. RESULTS: The results proved that the foramen of Huschke can be observed in skulls submitted to contrast using radiographic techniques.


Asunto(s)
Hueso Temporal/diagnóstico por imagen , Articulación Temporomandibular/diagnóstico por imagen , Adulto , Oído Medio , Humanos , Persona de Mediana Edad , Radiografía Panorámica , Hueso Temporal/anatomía & histología , Articulación Temporomandibular/anatomía & histología , Tomografía Computarizada por Rayos X
20.
Braz Oral Res ; 29: 49, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25760067

RESUMEN

The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB) has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT). Twenty CBCT images of 40 temporo mandibular joints (TMJs) in individuals in mixed dentition phase, which included 9 males (mean 7.9 years) and 11 females (mean 8.2 years), with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (< 40 mm), congenital or genetic anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane.


Asunto(s)
Dentición Mixta , Maloclusión/diagnóstico por imagen , Maloclusión/patología , Cóndilo Mandibular/anatomía & histología , Cóndilo Mandibular/diagnóstico por imagen , Análisis de Varianza , Niño , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Imagenología Tridimensional , Masculino , Variaciones Dependientes del Observador , Estudios Prospectivos , Valores de Referencia , Articulación Temporomandibular/diagnóstico por imagen
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