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1.
Clin Oral Investig ; 27(5): 2321-2333, 2023 May.
Article in English | MEDLINE | ID: mdl-36515761

ABSTRACT

OBJECTIVE: We performed a systematic review to investigate the appearance of imaging signs on magnetic resonance imaging (MRI), cone-beam computed tomography (CBCT), and conventional computed tomography (CT) scans of the temporomandibular joints (TMJs) of patients with juvenile idiopathic arthritis (JIA). MATERIALS AND METHODS: We performed electronic searches of the PubMed, Embase, Web of Science, Scopus, Lilacs, and the Cochrane Library databases to identify studies investigating JIA and its related imaging findings. Inclusion criteria were as follows: original article studies based on humans and systematic reviews, studies enrolling patients under 18 years of age with a diagnostic of JIA, the use of International League of Associations for Rheumatology (ILAR) criteria and one type of medical imaging (MRI, CBCT, or CT), and papers published in the English language. RESULTS: A total of six studies met the inclusion criteria, four involving MRI and two involving CBCT. Additionally, all six studies analyzed the imaging findings of pathological TMJ affected by JIA. The results showed that synovial membrane enhancement, condylar erosions, and condylar flattening were the most prevalent imaging findings in JIA. CONCLUSION: MRI examinations are more specific for detecting anomalies in the TMJ than CBCT and CT. Additionally, these results must be correlated with clinical signs to verify the correct diagnosis. CLINICAL RELEVANCE: This study identified the most prevalent imaging signs of JIA to provide an early and correct diagnosis of the disease.


Subject(s)
Arthritis, Juvenile , Spiral Cone-Beam Computed Tomography , Temporomandibular Joint Disorders , Humans , Adolescent , Arthritis, Juvenile/diagnostic imaging , Temporomandibular Joint Disorders/pathology , Temporomandibular Joint/diagnostic imaging , Temporomandibular Joint/pathology , Magnetic Resonance Imaging/methods
2.
J Endod ; 47(12): 1829-1843.e1, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34425149

ABSTRACT

INTRODUCTION: The present study aimed to review the epidemiologic, topographic, and morphometric aspects of the mental foramen (MF) and anterior loop (AL) on cone-beam computed tomographic imaging studies. METHODS: An International Prospective Register of Systematic Reviews (PROSPERO)-registered systematic review (CRD42018112991) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two reviewers independently performed data extraction from observational studies that evaluated MF and AL on 7 electronic databases. MedCalc (MedCalc Software bv, Ostend, Belgium) software was used to perform a meta-analysis with a 95% confidence level. RESULTS: Of 1545 articles, 66 met the inclusion criteria, totaling 14,233 patients from 5 continents, with a total of 6655 females and 5884 males (some studies did not report sex), with an age range between 8 and 89 years. The most prevalent shapes of MF were oval (48.72%) and circular (44.36%), and the most frequent horizontal positions were between premolars (43.66%) and in line with the long axis of the second premolar (43.12%). CONCLUSIONS: Based on the articles that assessed AL, the mean prevalence was 43.18%, with most studies reporting bilateral localization as the most prevalent.


Subject(s)
Mental Foramen , Adolescent , Adult , Aged , Aged, 80 and over , Bicuspid , Child , Cone-Beam Computed Tomography , Female , Humans , Male , Mandible , Middle Aged , Software , Young Adult
3.
Int. j. morphol ; 31(4): 1386-1392, Dec. 2013. ilus
Article in English | LILACS | ID: lil-702322

ABSTRACT

This paper aimed to analyze stress distribution in human zygomatic pillar during masseter muscle contraction using three-dimensional finite element analysis. A three-dimensional model and hemi facial skull were produced based on CT-scan data. An adult male skull with structural anatomy integrity was used as model. Muscles forces were applied at origin of elevator muscles and supports was applied at the occlusal surfaces at first and second molars to simulate a masticatory load and stimulate the zygomatic pillar. Supports were applied to the occlusal contacts. Symmetry conditions were placed at the mid-sagittal plane. For the top and back cutting plane, constraints were used. Equivalent Von-Mises Stress and Maximum Principal Stress analysis were performed from the stress fields along the zygomatic pillar. It was represented by stress concentration at the alveolar process, zygomatic bone, frontal and temporal process of zygomatic bone and superciliary arch. Stress line indicates distribution of stress from maxilla toward the frontal and temporal bone. The stresses occurred due to resultant occlusal forces is mainly supported by the zygomatic bone, non-uniformly distributed and predominantly through the zygomatic pillar. This study contributed to better understanding of stress distribution in zygomatic pillar to understand the influence of chewing on zygomatic pillar morphology and also be useful for clinical practice.


El objetivo de este artículo fue analizar la distribución de la tensión en el pilar cigomático humano durante la contracción del músculo masetero utilizando análisis de elementos finitos tridimensionales. Un modelo de tres dimensiones de dientes del hemicráneo facial fueron producidos sobre la base de datos de CT-scan. Se utilizó como modelo un cráneo adulto de sexo masculino con la integridad de la anatomía estructural. Fuerzas musculares se aplicaron en el origen de los ascensores de los músculos de la mandíbula y soportes se aplicaron a la superficie oclusal del primer y segundo molar para simular una carga masticatoria y estimular el pilar cigomático. Condiciones de simetría se colocaron en el plano mediano. Se utilizaron restricciones en los planos superior y posterior. El análisis de las tensiones equivalentes von-Mises y máximo director se realizó a través del campo de esfuerzos a lo largo del pilar cigomático. Fue representada la concentración de esfuerzos en el proceso alveolar, hueso cigomático, proceso frontal y temporal del hueso cigomático y el arco superciliar. La línea de tensión indica la distribución de la tensión del maxilar hacia el hueso frontal y temporal. Las tensiones se produjeron debido a las fuerzas oclusales resultantes, que se apoyan principalmente por el hueso cigomático, distribuidas de manera no uniforme y sobre todo a través del pilar cigomático. Este estudio ha contribuido a una mejor comprensión de la distribución de la tensión en el pilar cigomático para entender la influencia de la masticación sobre la morfología de este pilar y ser de utilidad en la práctica clínica.


Subject(s)
Humans , Zygoma/anatomy & histology , Zygoma/physiology , Skull/anatomy & histology , Finite Element Analysis , Biomechanical Phenomena , Imaging, Three-Dimensional
4.
RFO UPF ; 18(2): 175-179, Mai.-Ago. 2013. ilus, tab
Article in English | LILACS | ID: lil-720738

ABSTRACT

Objective: this study aimed to assess the radiopacity of eight composite resins recommended for class II restorations. Materials and method: hence, 2 mm thick and 4 mm in diameter test specimens were made and compared to enamel, dentin, and aluminum using four digital systems: two semi-direct by storage phosphor image plates (SPIP) - Digora™, and DenOptix™, two charged couple devices (CCD) - Sens-A-Ray™ and Computerized Dental Radiograph (CDR™), and radiographic film Kodak Insight IS-21™. The radiographs were scanned to obtain the indirect digital image, and along with direct and semi-direct digital images the radiographic densities were assessed in specific software. The pixel values from the aluminum step wedge were submitted to a linear regression from where the equivalent in millimeters for enamel, dentin, and resins were determined. Results: density means of resins were equal or superior to the means obtained for enamel in all digital systems and the conventional film. SureFil™ resin presented greater numerical radiopacity in all digital systems and the radiographic film. ALERT™ resin showed the smallest radiopacity among the studied resins in all digital systems and radiographic film. ALERT™ and Definite™ were statistically equivalent to enamel in the Sens-A-Ray™ system and in radiographic film. The remaining resins (Charisma™, FillMagic™, P60™, Prodigy™, SureFil™, and Z250™) presented higher radiopacities in comparison to enamel. Only ALERT™ presented radiopacity similar to enamel in other digital systems (CDR™, DenOptix™, and Digora™). In these digital systems, Charisma™, Definite™, FillMagic™, P60™, Prodigy™, SureFil™, and Z250™ were more radiopaque than enamel. Conclusion: all resins showed equal or higher radiopacities of enamel in all assessment systems. There was a statistical correlation between systems CDR™ and Sens-A-Ray™, and between Digora™ and DenOptix™; Sens-A-Ray™ also showed correlation with radiographic film. The percentage of density means equivalent to aluminum millimeters for enamel and dentin were 119.6% and 101.6%, respectively.


Objetivo: este estudo teve como objetivo avaliar a radiopacidade de oito tipos de resinas compostas indicadas para restaurações de classe II. Materiais e método: para tanto foram confeccionados corpos de prova de 2 mm de espessura e 4 mm de largura, os quais foram comparados com esmalte, dentina e alumínio, utilizando- se quatro sistemas digitais, sendo dois semidiretos por placas de fósforo fotoestimuladas - Digora® e DenOptix ®, dois CCD - Sens-A-Ray® e CDR®, e também o filme radiográfico Kodak Insight IS-21®. As radiografias foram escaneadas, obtendo-se imagem digital indireta, e, juntamente com as imagens digitais diretas e semidiretas, suas densidades radiográficas foram avaliadas em software específico. Os valores de pixel da escala de alumínio foram submetidos a uma regressão linear, de onde se pôde obter o equivalente em milímetros para o esmalte, dentina e resinas. Resultados: para todos os sistemas digitais e para o filme convencional, as médias das densidades das resinas foram iguais ou superiores às médias obtidas pelo esmalte. Para todos os sistemas digitais e para o filme radiográfico, a resina Surefil® apresentou maior radiopacidade numérica. A resina ALERT® apresentou a menor radiopacidade entre as resinas estudadas em todos os sistemas digitais e filme radiográfico. ALERT® e Difinite® foram estatisticamente equivalentes ao esmalte no sistema digital Sens-A-Ray® e no filme radiográfico. As demais resinas (Charisma®, FillMagic®, P60®, Prodigy®, Surefil® e Z250®) tiveram maior radiopacidade em comparação ao esmalte. Somente ALERT® teve radiopacidade similar à do esmalte em outros sistemas digitais (CDR®, Denoptix® e Digora ®). Nesses sistemas digitais, Charisma®, FillMagic®, P60®, Prodigy®, Surefil® e Z250® foram mais radiopacos do que o esmalte. Conclusão: todas as resinas, em todos os sistemas de avaliação, mostraram radiopacidade igual ou superior ao esmalte. Houve correlação estatística entre os sistemas CDR® e Sens-A-Ray® e entre Digora ® e DenOptix®, tendo o Sens-A-Ray® apresentado correlação também com o filme radiográfico. As médias de densidade equivalente em mm de alumínio em porcentagem para esmalte e dentina foram de 119,6% e 101,6%, respectivamente.

5.
Clin Oral Investig ; 11(4): 331-6, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17598135

ABSTRACT

The purpose of this study was to evaluate the radiodensity of indirect restorative systems and to determine its influence on detection of resin cement overhangs. Sixty sound molars with similar dimensions were selected, and MOD inlay preparations were made in a standardized fashion with 6 degrees taper of the walls. Restorations were made with a porcelain, Duceram LFC, and with three indirect composites, Solidex, Artglass, and Targis. Digital radiographic images were taken before and after cementation of the inlays (Digora system) and were analyzed on two regions, the cervical and the isthmus floor. Digital radiodensity measurements were performed on standardized points symmetrically distributed over each restoration and tooth structure. Cement overhangs were detected through visual analysis by three evaluators. Data were statistically analyzed utilizing ANOVA following Tukey's test (p < 0.05), showing that Solidex presented lower radiodensity than Duceram LFC, and both Artglass and Targis presented similar higher levels of radiodensity than the other groups. Radiodensity of cervical regions was always greater than for isthmus floor regions. Detection of the resin cement overhangs is easier observed on Solidex and Duceram LFC. Radiodensity is highly influenced by restorative material type and tooth regions. The detection of radiopaque resin cement overhangs is influenced by radiodensity of restorative materials.


Subject(s)
Composite Resins/chemistry , Dental Porcelain/chemistry , Inlays , Resin Cements/chemistry , Absorptiometry, Photon , Cementation , Dental Cavity Preparation/methods , Glass Ionomer Cements/chemistry , Humans , Materials Testing , Molar/diagnostic imaging , Radiography, Dental, Digital , Silicate Cement/chemistry , Surface Properties , Tooth Cervix/diagnostic imaging
6.
J Oral Maxillofac Surg ; 64(9): 1359-65, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16916669

ABSTRACT

PURPOSE: Loss of ridge width and height typically occur after tooth extraction. This study aimed to investigate whether smoking would effect alveolar ridge remodeling after tooth extraction. MATERIALS AND METHODS: Twenty-one individuals (11 nonsmokers, 10 smokers) requiring a nonmolar extraction in the upper jaw were selected. Radiographs were taken 7 and 180 days after surgery, and the following parameters obtained: alveolar process height (AH), alveolar process width (AW), radiographic bone density in the postextraction socket (BDS), and in the pre-existing bone apically (BDPB). RESULTS: Six months after surgery, intragroup analysis showed that both groups presented a significant reduction in AH, while only smokers had a significant reduction in AW, BDS, and BDPB (P < .05). Furthermore, intergroup analysis showed that smokers presented lower BDS (91.45 pixels +/- 26.62 and 59.53 pixels +/- 19.99, for nonsmokers and smokers, respectively; P = .006) and continued to present lower BDPB (129.34 pixels +/- 42.10 and 89.29 pixels +/- 29.96, for nonsmokers and smokers, respectively; P = .023). Additionally, smokers presented a tendency for lower AH and AW than nonsmokers, but this was not statistically significant. CONCLUSION: Within the limits of the present study, smoking may lead to a more significant dimensional reduction of the residual alveolar ridge and postpone postextraction socket healing.


Subject(s)
Alveolar Process/physiopathology , Bone Density/physiology , Bone Remodeling/physiology , Maxilla/physiopathology , Smoking/adverse effects , Tooth Extraction , Absorptiometry, Photon , Adult , Aged , Alveolar Bone Loss/etiology , Alveolar Process/diagnostic imaging , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Prospective Studies , Radiography, Bitewing , Radiography, Panoramic , Smoking/physiopathology , Tooth Socket/diagnostic imaging , Tooth Socket/physiopathology , Wound Healing/physiology
7.
Am J Dent ; 18(1): 57-60, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15810483

ABSTRACT

PURPOSE: To compare through digital radiographic analysis the radiodensity levels of seven prefabricated post systems inserted in root canals of bovine extracted incisors. METHODS: 21 bovine teeth were cut 15 mm from the apical limit. The canals were prepared according to the manufacturer's instructions using specific bur of each post system analyzed: three metallic posts: Flexi-Flange, Radix-Anker, and FKG post; one zirconium ceramic post: Cosmopost; one carbon fiber post: C-Post; one carbon fiber post system covered with quartz fiber: AEsthetic Post; and one glass fiber reinforced post: FibreKor Post. Root tooth digital analyses were made with Digora system with and without the insertion of post. Their variations were obtained subtracting radiodensity of the post from radiodensity of the root canal, in cervical, medium, and apical thirds of the root canal. Two-way ANOVA and Tukey test (P< 0.05) were used to analyze the data. RESULTS: This study showed that the radiopacity of post systems is dependent on their composition. Statistical differences were found among radiodensity levels in apical third, medium and cervical thirds for all post systems inside the root canals. Statistical differences were also found among the post systems: ceramic posts showed the highest radiodensity level, followed by metallic posts, carbon fiber posts, glass fiber posts, and the carbon fiber post covered with quartz fiber. These results indicate that biomechanical post systems have low radiodensity levels.


Subject(s)
Dental Pulp Cavity/diagnostic imaging , Post and Core Technique , Radiography, Dental, Digital , Absorptiometry, Photon , Analysis of Variance , Animals , Carbon , Carbon Fiber , Cattle , Composite Resins , Metals , Quartz , Statistics, Nonparametric , Tooth, Nonvital/diagnostic imaging , Zirconium
8.
J Periodontol ; 76(4): 520-5, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15857091

ABSTRACT

BACKGROUND: It has been previously shown that cigarette smoke inhalation (CSI) enhances bone loss in ligature-induced periodontitis. In this study, the hypothesis that the interruption of smoke exposure would reverse the impact of CSI on mandibular bone quality and periodontitis-related bone loss was tested. METHODS: Fifty-three Wistar rats were randomly assigned to one of the following groups: group 1: control, N = 16; group 2: 83 days of CSI prior to ligature placement, N = 17; or group 3: 90 days of CSI before and 60 days after ligature placement, N = 20. Animals were sacrificed 60 days after ligature placement, the jaws removed and immediately radiographed for photodensitometry analysis. Bone loss was histometrically evaluated. RESULTS: CSI did not affect unligated sites in either condition (P >0.05); however, smoke inhalation during the whole experimental period significantly enhanced bone loss in ligated teeth (P < 0.05). Moreover, similar levels of bone loss were observed for ligated teeth between the control and cessation groups (0.90 +/- 0.33 mm(2); 0.96 +/- 0.32 mm(2); 1.64 +/- 0.65 mm(2); groups 1, 2 and 3, respectively). Radiographically, continuous exposure to cigarette smoke promoted a significantly reduced bone density (1.74 +/- 0.38 aluminum equivalence [Al eq]; 1.74 +/- 0.14 Al eq; and 0.68 +/- 0.10 Al eq for groups 1, 2, and 3, respectively). CONCLUSIONS: Within the limits of the present investigation, it can be assumed that CSI may enhance bone loss in ligature-induced periodontitis, and negatively impact mandibular bone quality. Additionally, smoke exposure cessation seems to reverse its impact on mandibular bone, and, therefore, may be of clinical relevance.


Subject(s)
Alveolar Bone Loss/prevention & control , Smoking Cessation , Absorptiometry, Photon , Alveolar Bone Loss/diagnostic imaging , Alveolar Bone Loss/etiology , Analysis of Variance , Animals , Bone Density , Ligation , Male , Mandible/diagnostic imaging , Mandible/pathology , Periodontitis/diagnostic imaging , Periodontitis/etiology , Random Allocation , Rats , Rats, Wistar , Smoking/adverse effects , Statistics, Nonparametric
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