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1.
Sci Rep ; 14(1): 5987, 2024 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-38472272

RESUMEN

This study aimed to evaluate the association between single nucleotide polymorphisms (SNPs) in endochondral development-related genes and mandibular condyle shape, size, volume, and symmetry traits. Cone-beam Computed Tomographies and genomic DNA from 118 individuals were evaluated (age range: 15-66 years). Data from twelve 3D landmarks on mandibular condyles were submitted to morphometric analyses including Procrustes fit, principal component analysis, and estimation of centroid sizes and fluctuating asymmetry scores. Condylar volumes were additionally measured. Seven SNPs across BMP2, BMP4, RUNX2 and SMAD6 were genotyped. Linear models were fit to evaluate the effect of the SNPs on the mandibular condyles' quantitative traits. Only the association between BMP2 rs1005464 and centroid size remained significant after adjusting to account for the false discovery rate due to multiple testing. Individuals carrying at least one A allele for this SNP showed larger condylar size than common homozygotes GG (ß = 0.043; 95% CI: 0.014-0.071; P value = 0.028). The model including BMP2 rs1005464, age and sex of the participants explained 17% of the variation in condylar size. Shape, volume, and symmetry were not associated with the evaluated SNPs. These results suggest that BMP2 rs1005464 might be associated with variation in the mandibular condyles size.


Asunto(s)
Maloclusión , Cóndilo Mandibular , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Tomografía Computarizada de Haz Cónico/métodos , Alelos , Genotipo , Proteína Morfogenética Ósea 2
2.
Orthod Craniofac Res ; 27(2): 321-331, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38009409

RESUMEN

OBJECTIVE(S): This study aims to evaluate the influence of the piezocision surgery in the orthodontic biomechanics, as well as in the magnitude and direction of tooth movement in the mandibular arch using novel artificial intelligence (AI)-automated tools. MATERIALS AND METHODS: Nineteen patients, who had piezocision performed in the lower arch at the beginning of treatment with the goal of accelerating tooth movement, were compared to 19 patients who did not receive piezocision. Cone beam computed tomography (CBCT) and intraoral scans (IOS) were acquired before and after orthodontic treatment. AI-automated dental tools were used to segment and locate landmarks in dental crowns from IOS and root canals from CBCT scans to quantify 3D tooth movement. Differences in mesial-distal, buccolingual, intrusion and extrusion linear movements, as well as tooth long axis angulation and rotation were compared. RESULTS: The treatment time for the control and experimental groups were 13.2 ± 5.06 and 13 ± 5.52 months respectively (P = .176). Overall, anterior and posterior tooth movement presented similar 3D linear and angular changes in the groups. The piezocision group demonstrated greater (P = .01) mesial long axis angulation of lower right first premolar (4.4 ± 6°) compared with control group (0.02 ± 4.9°), while the mesial rotation was significantly smaller (P = .008) in the experimental group (0.5 ± 7.8°) than in the control (8.5 ± 9.8°) considering the same tooth. CONCLUSION: The open source-automated dental tools facilitated the clinicians' assessment of piezocision treatment outcomes. The piezocision surgery prior to the orthodontic treatment did not decrease the treatment time and did not influence in the orthodontic biomechanics, leading to similar tooth movements compared to conventional treatment.


Asunto(s)
Inteligencia Artificial , Técnicas de Movimiento Dental , Humanos , Resultado del Tratamiento , Diente Premolar , Técnicas de Movimiento Dental/métodos , Tomografía Computarizada de Haz Cónico
3.
AJO DO Clin Companion ; 3(2): 93-109, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37636594

RESUMEN

Treatment effects occurring during Class II malocclusion treatment with the clear aligner mandibular advancement protocol were evaluated in two growing patients: one male (12 years, 3 months) and one female (11 years, 9 months). Both patients presented with full cusp Class II molar and canine relationships. Intraoral scans and cone-beam computed tomography were acquired before treatment and after mandibular advancement. Three-dimensional skeletal and dental long-axis changes were quantified, in which the dental long axis was determined by registering the dental crowns obtained from intraoral scans to the root canals in cone-beam computed tomography scans obtained at the same time points. Class II correction was achieved by a combination of mandibular skeletal and dental changes. A similar direction of skeletal and dental changes was observed in both patients, with downward and forward displacement of the mandible resulting from the growth of the mandibular condyle and ramus. Dental changes in both patients included mesialization of the mandibular posterior teeth with flaring of mandibular anterior teeth. In these two patients, clear aligner mandibular advancement was an effective treatment modality for Class II malocclusion correction with skeletal and dental effects and facial profile improvement.

4.
Am J Orthod Dentofacial Orthop ; 164(4): 491-504, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37037759

RESUMEN

INTRODUCTION: This study aimed to develop a 3-dimensional (3D) characterization of the severity of maxillary impacted canines and to test the clinical performance of this characterization as a treatment decision support tool. METHODS: Cone-beam computed tomography images obtained from 83 patients with 120 impacted maxillary canines were included. Quantitative information on the canine 3D position and qualitative assessment of root damage of adjacent teeth were evaluated. A severity index was constructed on the basis of the quantitative findings. Clinical applicability was tested by comparing clinical diagnosis and treatment planning for conventional records vs the 3D characterization via a 2-part survey. RESULTS: The average quantitative assessments of impacted maxillary canine position were 6.4 ± 3.6 mm from the midsagittal plane, 11.6 ± 3.1 mm in height relative to the occlusal plane, 31.5° ± 18° of roll, and 48.8° ± 14.3° of pitch. The severity index ranged from 0-13 with a mean score of 4.5 ± 2.2. Overlap with adjacent teeth was the greatest contributor (33%) to the index. Bicortically impacted canines caused the most severe root damage. Cone-beam computed tomography was preferred for assessing root damage and overall severity, whereas conventional imaging was sufficient for height and angulation assessment. The 3D report was very important or important for evaluating root damage, canine position, overall severity, and overlap. The 3D report changed most of the decisions relating to biomechanics, patient education, and treatment time estimate. The decision of exposure and traction vs extraction was changed 22% of the time after the presentation of the 3D report. CONCLUSIONS: The overlap with adjacent teeth frequently contributes the most to the severity index. The 3D report provided relevant clinical information regarding the canine position, damage to adjacent teeth, and the severity index, with a profound impact on the decisions of the clinicians regarding biomechanics, patient education, and treatment time estimate.


Asunto(s)
Resorción Radicular , Diente Impactado , Humanos , Maxilar , Tomografía Computarizada de Haz Cónico/métodos , Diente Impactado/diagnóstico por imagen , Diente Impactado/terapia , Diente Impactado/complicaciones , Diente Canino/diagnóstico por imagen , Tracción/efectos adversos , Resorción Radicular/etiología
5.
J Anat ; 241(6): 1273-1286, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36087285

RESUMEN

An important parameter in diagnostic analysis and treatment planning of different biological areas is facial symmetry, and several etiological factors have been attributed to skeletal facial asymmetry. Although causality cannot be determined, previous studies have reported a relationship between the anatomical deviation of the nasal septum and facial development. Diagnosis is critical for patients in growth stages due to the association between nasal septum deviation (NSD) and abnormal growth of the nasomaxillary complex. To understand this relationship, this study aimed to investigate the influence of nasal septum deviation on fluctuating asymmetries (FA) of the nasomaxillary complex at different stages of skeletal maturation. Another goal was to determine whether an association exists between the degrees of septal deviation severity and asymmetry of the nasomaxillary complex. This was a retrospective, cross-sectional observational study comprising 60 selected cone-beam computed tomography (CBCT) scans that were divided into four groups (n = 15) according to the degree of septal deviation and skeletal maturation: mild deviation (MD; <10°), moderate to severe deviation (MSD; ≥10°), early group (EG), and late group (LG). The angle and area of deviation were measured for the greatest NSD, and a geometric morphometric approach was used to evaluate the nasal septum (NS) shape. The morphology of the nasomaxillary complex and the presence of fluctuating asymmetries were evaluated using 23 two-dimensional landmarks on the nasomaxillary complex (nasal, lateral, and palatal regions) with Procrustes ANOVA and Mann-Whitney test. Additionally, Spearman's correlation and multivariate regression were used to correlate the NSD with asymmetries in these regions. No significant differences were observed in the Procrustes FA scores of the nasomaxillary complex between the MD-EG × MSD-EG and MD-LG × MSD-LG (p > 0.05). However, the results of the multivariate regression revealed more specific aspects of asymmetry (asymmetry component), there was a positive correlation between the NSD angle and the palatal regions (p = 0.035 and p = 0.047, middle and posterior, respectively), and the nasal septum shape and anterior palatal regions (p = 0.039). The nasal and lateral regions did not correlate with the NSD angle in the multivariate regression analysis (p > 0.05). The results of this study indicate that there were no significant differences in the fluctuating asymmetry of the nasomaxillary complex between the mild and moderate to severe nasal septum deviation groups, in both early and late skeletal maturation stages. However, a positive correlation was observed in the degree of nasal septum deviation angle and asymmetry components of the middle and posterior palatal regions, likewise between the nasal septum shape and asymmetry components of the anterior palatal region. The diagnosis of nasal septum deviation by both physicians and dentists is important, as a relationship was observed with fluctuating asymmetry component of the palatal region. This information can guide the decision of the treatment planning for these individuals, and should be considered, especially in cases of severe septum deviation, due to the great anatomical proximity of these structures.


Asunto(s)
Asimetría Facial , Tabique Nasal , Humanos , Estudios Transversales , Estudios Retrospectivos , Tabique Nasal/diagnóstico por imagen , Tabique Nasal/anatomía & histología , Cara
6.
Am J Orthod Dentofacial Orthop ; 162(4): 491-501, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35798623

RESUMEN

INTRODUCTION: This study aimed to 3-dimensionally quantify and compare the outcomes of growing patients with Class II malocclusion treated with the cervical pull face-bow headgear appliance in combination with full fixed orthodontic appliances. METHODS: The study sample consisted of 22 patients with Class II malocclusion with the following inclusion criteria: ANB >4.75°, Class II molar relationship, and SN-GoGn <37°. The mean age of patients was 12.5 ± 1.1 years at baseline. The average treatment time was 27.7 ± 7.3 months. Cone-beam computed tomography scans were superimposed in the cranial base, maxillary regional, and mandibular regional to evaluate growth, treatment displacements, and bone remodeling. RESULTS: Relevant statistically and clinically significant skeletal changes included average decreases in ANB (2.1 ± 1.1°) and SNA (1.8 ± 1.1°); posterior (1.3 ± 1.4 mm) and inferior (4.6 ± 2.2 mm) displacement of A-point; inferior displacements of B-point (5.4 ± 2.8 mm) and Pogonion (5.8 ± 2.6 mm); superior displacement of Condylion (6.9 ± 2.4 mm); increase in mandibular length (5.4 ± 2.0 mm); and clockwise rotation of palatal plane (1.9 ± 1.9°). Significant proclination of the maxillary incisors (9.8 ± 11.1°) and nonsignificant proclination of the mandibular incisors (4.7 ± 9.6°) were also noted. CONCLUSIONS: Class II skeletal correction was primarily achieved by posterior, inferior displacement of the sagittal position of the maxilla. Change in the sagittal position of the mandible/chin (B-point, Pogonion) was not significant; rather, mandibular displacement was significant in an inferior vertical direction without backward rotation, as seen from marked condylar and ramus growth.


Asunto(s)
Maloclusión Clase II de Angle , Adolescente , Cefalometría/métodos , Niño , Aparatos de Tracción Extraoral , Humanos , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/terapia , Mandíbula/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Tecnología
7.
Angle Orthod ; 92(1): 118-126, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34546287

RESUMEN

OBJECTIVES: To analyze the prevalence of mandibular asymmetry in skeletal sagittal malocclusions. MATERIALS AND METHODS: PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO and gray literature (OpenGrey, ProQuest, and Google Scholar) were electronically searched. Two independent investigators selected the eligible studies, and assessed risk of bias and certainty of evidence (GRADE). One reviewer independently extracted the data and the second reviewer checked this information. Any disagreement between the reviewers in each phase was resolved by discussion between them and/or involved a third reviewer for final decision. RESULTS: Electronic search identified 5,132 studies, and 5 observational studies were included. Risk of bias was low in two studies, moderate in one, and high in two. The studies showed high heterogeneity. Mandibular asymmetry ranged from 17.43% to 72.95% in overall samples. Horizontal chin deviation showed a prevalence of 17.66% to 55.6% asymmetry in Class I malocclusions, and 68.98% in vertical asymmetry index. In Class II patients, prevalence of mandibular asymmetry varied from 10% to 25.5% in horizontal chin deviation, and 71.7% in vertical asymmetry index. The Class III sample showed a prevalence of mandibular asymmetry ranging from 22.93% to 78% in horizontal chin deviation and 80.4% in vertical asymmetry index. Patients seeking orthodontic or orthognathic surgery treatment showed greater prevalence of mandibular asymmetry. CONCLUSIONS: Skeletal Class III malocclusion showed the greatest prevalence of mandibular asymmetry. Mandibular vertical asymmetry showed a marked prevalence in all malocclusions. However, conclusions should be interpreted with caution due to use of convenience samples and low-quality study outcomes.


Asunto(s)
Maloclusión de Angle Clase III , Maloclusión Clase II de Angle , Procedimientos Quirúrgicos Ortognáticos , Cefalometría , Asimetría Facial/epidemiología , Humanos , Maloclusión de Angle Clase III/epidemiología , Mandíbula , Prevalencia
8.
Sci Rep ; 10(1): 8012, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32415284

RESUMEN

After chronic low back pain, Temporomandibular Joint (TMJ) disorders are the second most common musculoskeletal condition affecting 5 to 12% of the population, with an annual health cost estimated at $4 billion. Chronic disability in TMJ osteoarthritis (OA) increases with aging, and the main goal is to diagnosis before morphological degeneration occurs. Here, we address this challenge using advanced data science to capture, process and analyze 52 clinical, biological and high-resolution CBCT (radiomics) markers from TMJ OA patients and controls. We tested the diagnostic performance of four machine learning models: Logistic Regression, Random Forest, LightGBM, XGBoost. Headaches, Range of mouth opening without pain, Energy, Haralick Correlation, Entropy and interactions of TGF-ß1 in Saliva and Headaches, VE-cadherin in Serum and Angiogenin in Saliva, VE-cadherin in Saliva and Headaches, PA1 in Saliva and Headaches, PA1 in Saliva and Range of mouth opening without pain; Gender and Muscle Soreness; Short Run Low Grey Level Emphasis and Headaches, Inverse Difference Moment and Trabecular Separation accurately diagnose early stages of this clinical condition. Our results show the XGBoost + LightGBM model with these features and interactions achieves the accuracy of 0.823, AUC 0.870, and F1-score 0.823 to diagnose the TMJ OA status. Thus, we expect to boost future studies into osteoarthritis patient-specific therapeutic interventions, and thereby improve the health of articular joints.


Asunto(s)
Biomarcadores , Aprendizaje Automático , Osteoartritis/diagnóstico , Osteoartritis/metabolismo , Trastornos de la Articulación Temporomandibular/diagnóstico , Trastornos de la Articulación Temporomandibular/metabolismo , Área Bajo la Curva , Análisis de Datos , Bases de Datos Factuales , Diagnóstico Precoz , Femenino , Humanos , Masculino , Osteoartritis/etiología , Curva ROC , Radiografía , Reproducibilidad de los Resultados , Evaluación de Síntomas , Trastornos de la Articulación Temporomandibular/etiología
9.
Am J Orthod Dentofacial Orthop ; 158(2): 209-220, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32451206

RESUMEN

INTRODUCTION: This study aimed to evaluate the morphologic and positional features of the mandible in children, adolescents, and adults with skeletal Class I and unilateral posterior crossbite. METHODS: The sample included cone-beam computerized tomography images of 76 subjects, divided in 3 groups: (1) children (aged 6.77 ± 1.5 years; n = 25), (2) adolescents (aged 14.3 ± 1.7 years; n = 26), and (3) adults (aged 32.66 ± 13.4 years; n = 25) with unilateral posterior crossbite. Condylar and mandibular linear distances and angles were performed using a mirrored 3-dimensional overlapped model. Intragroup asymmetries were determined by a comparison between crossbite and no crossbite sides. The differences between both sides of all measurements were compared among groups and correlated to mandibular horizontal rotation (yaw) and age. RESULTS: The crossbite side showed shorter distances in the condyle and mandibular regions. Asymmetries were slightly but significantly greater in adults, as expressed by the lateromedial condylar distance, total ramus height, and mandibular length with an average 0.7 mm, 2.0 mm, and 1.5 mm, respectively. The mandibular yaw rotation was not correlated to age but moderately associated (r = 0.467) to asymmetry in mandibular length and total ramus height. CONCLUSIONS: Patients with skeletal Class I and unilateral crossbite showed small mandibular asymmetries and these conditions were slightly greater in adults, specifically in lateromedial condylar distances and mandibular body and length.


Asunto(s)
Maloclusión , Adolescente , Adulto , Niño , Preescolar , Tomografía Computarizada de Haz Cónico , Asimetría Facial , Humanos , Mandíbula , Cóndilo Mandibular , Persona de Mediana Edad , Adulto Joven
10.
Artículo en Inglés | MEDLINE | ID: mdl-33415323

RESUMEN

The biggest challenge to improve the diagnosis and therapies of Craniomaxillofacial conditions is to translate algorithms and software developments towards the creation of holistic patient models. A complete picture of the individual patient for treatment planning and personalized healthcare requires a compilation of clinician-friendly algorithms to provide minimally invasive diagnostic techniques with multimodal image integration and analysis. We describe here the implementation of the open-source Craniomaxillofacial module of the 3D Slicer software, as well as its clinical applications. This paper proposes data management approaches for multisource data extraction, registration, visualization, and quantification. These applications integrate medical images with clinical and biological data analytics, user studies, and other heterogeneous data.

11.
Orthod Craniofac Res ; 22(3): 183-193, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30844126

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the reliability of 3-dimensional maxillary dental changes using two methods of digital model superimposition. SETTING AND SAMPLE POPULATION: The Department of Orthodontics of Bauru Dental School, University of São Paulo and University of Michigan Craniofacial Growth Center. Fifteen subjects with normal occlusion. MATERIAL & METHODS: The sample was composed of digital study models of 15 normal occlusion subjects taken at 13 (T1), 18 (T2) and 60 years of age (T3). Using the software SlicerCMF 3.1, superimposition (registration) was conducted using 9 landmarks placed on the incisive papilla, second and third palatal rugae and 10 mm distal to the third palatal rugae. Two registration methods were compared: landmarks (LA) and regions of interest (ROI). Three-dimensional changes of landmarks on the buccal cusp tip of posterior teeth bilaterally and the incisal edge of the right central incisor were measured by three examiners. Intraclass correlation coefficients and Bland-Altman method evaluated intra- and inter-examiner agreements. RESULTS: Good or excellent intra-examiner agreement was found for T1-T2 and T2-T3 measurements using both registration methods. Inter-examiner agreements were good to excellent for T1-T2 measurements and poor to fair for most T2-T3 measurements. Mean T1-T2 differences were less than 0.5 mm for most measurements. CONCLUSION: Maxillary digital dental models of patients with normal occlusion superimposed on palatal rugae showed an adequate reliability for a 5-year interval comparison using landmarks or regions of interest. Lower than acceptable reproducibility using both superimposition methods was found for a 40-year interval comparison.


Asunto(s)
Envejecimiento , Maxilar , Humanos , Persona de Mediana Edad , Modelos Dentales , Hueso Paladar , Reproducibilidad de los Resultados
12.
Angle Orthod ; 88(6): 757-764, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30004786

RESUMEN

OBJECTIVES:: The purpose of this three-dimensional (3D) study was to assess retrospectively the middle cranial fossa and central skull base of patients treated with the Herbst appliance (HA). MATERIALS AND METHODS:: 3D surface virtual models of 40 Class II, division 1 malocclusion patients were generated from cone-beam computed tomography (CBCT) acquired before treatment (T0) and after 8 months of HA treatment (T1). T0 and T1 3D models were superimposed volumetrically at the anterior cranial fossa. Twenty subjects who had been treated with the Herbst appliance (HAG) were compared to 20 subjects who were not treated orthopedically. The latter group served as a comparison control group (CG). Quantitative assessments of the location and directional changes were made with linear and angular measurements between anatomical landmarks. Qualitative assessments of the spatial behavior of the middle cranial fossa and central skull base relative to the anterior cranial fossa were displayed graphically for visualization with color maps and semitransparent overlays. Non-parametric tests were performed to compare the between the HAG and CG. RESULTS:: Point-to-point linear measurements and skeletal rotation (pitch, roll, and yaw) changes were very small along the observational period and were not significantly different between HAG and CG. Visual analysis of color maps and overlays confirmed that no changes in the cranial base were associated with HA. CONCLUSIONS:: HA therapy did not produce clinically significant changes in the middle cranial fossa and central skull base.


Asunto(s)
Fosa Craneal Media/diagnóstico por imagen , Aparatos Ortodóncicos Funcionales , Base del Cráneo/diagnóstico por imagen , Adolescente , Estudios de Casos y Controles , Niño , Tomografía Computarizada de Haz Cónico , Fosa Craneal Media/anatomía & histología , Fosa Craneal Media/patología , Humanos , Imagenología Tridimensional , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/patología , Maloclusión Clase II de Angle/terapia , Aparatos Ortodóncicos Funcionales/efectos adversos , Base del Cráneo/anatomía & histología , Base del Cráneo/patología
13.
Artículo en Inglés | MEDLINE | ID: mdl-29754856

RESUMEN

The objective of this study was to report the clinical evaluation results and 3-dimensional (3-D) dental and craniofacial characteristics observed in 2 male patients with mucopolysaccharidosis type II. The patients were evaluated clinically (soft tissue evaluation, evaluation of occlusion, periodontal and dental examinations) and by using craniofacial computed tomography, with evaluation of 3-D images in ITK-Snap v. 2.2 (Penn Image Computing and Science Laboratory, Philadelphia, PA; http://www.itksnap.org/) and 3-D Slicer (http://www.slicer.org/) software. Mandibular 3-D volumetric label maps were built from computed tomography scans of both patients and compared through superimposition on a healthy patient's mandibular images. Clinically, the patients presented the following oral manifestations: macroglossia, total open bite and generalized diastemas, and absence of caries. Patient 1 showed dental calculus and bleeding at the gingival margin. Patient 2 showed bleeding at the gingival margin, a permanent maxillary left central incisor missing as a result of trauma, and impacted permanent mandibular left and right second molars. 3-D images showed wide arches, prominent antegonial notches, a narrow mandibular body in the region of the antegonial notches, bilateral severe condylar hypoplasia, and enlarged coronoid processes. 3-D imaging and superimpositions revealed oral and skeletal displacements, contributing to the identification of changes in the course of mucopolysaccharidosis type II in patients with a late diagnosis.

14.
Angle Orthod ; 87(6): 847-854, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28862492

RESUMEN

OBJECTIVES: To test the null hypotheses that the positions of the glenoid fossae and mandibular condyles are identical on the Class I and Class II sides of patients with Class II subdivision malocclusion. MATERIALS AND METHODS: Retrospective three-dimensional (3D) assessments of the positions of the glenoid fossae and mandibular condyles were made in patients with Class II malocclusion. Relative to a fiducial reference at the anterior cranial base, distances from the glenoid fossae and condyles were calculated in pretreatment cone beam computed tomographic scans of 82 patients: 41 with Class II and 41 with Class II subdivision malocclusions. The 3D distances from glenoid fossae to sella turcica in the X (right-left), Y (anterior-posterior), Z (inferior-superior) projections were calculated. RESULTS: Patients with Class II malocclusion displayed a symmetric position of the glenoid fossae and condyles with no statistically significant differences between sides (P > .05), whereas patients with Class II subdivision showed asymmetry in the distance between the glenoid fossae and anterior cranial base or sella turcica (P < .05), with distally and laterally positioned glenoid fossae on the Class II side. (P < .05). Male patients had greater distances between glenoid fossae and anterior cranial fossae (P < .05). The condylar position relative to the glenoid fossae did not differ between the two malocclusion groups nor between males and females (P > .05). CONCLUSIONS: The null hypotheses were rejected. Patients with Class II subdivision malocclusion displayed asymmetrically positioned right- and left-side glenoid fossae, with a distally and laterally positioned Class II side, although the condyles were symmetrically positioned within the glenoid fossae.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional , Maloclusión Clase II de Angle/diagnóstico por imagen , Cóndilo Mandibular/diagnóstico por imagen , Hueso Temporal/diagnóstico por imagen , Adolescente , Niño , Femenino , Humanos , Masculino , Cóndilo Mandibular/anatomía & histología , Estudios Retrospectivos , Hueso Temporal/anatomía & histología
15.
Turk J Orthod ; 29(2): 31-37, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30112471

RESUMEN

OBJECTIVE: To test the following two hypotheses regarding the consequences of Herbst appliance (HA) insertion: 1) a significant clockwise mandibular rotation will occur and 2) the displacement of the condyles will follow the same magnitude of the changes of overjet (OJ) and overbite (OB). METHODS: Virtual 3D surface models of 25 patients were generated from cone-beam computed tomographs taken before treatment and immediately after HA insertion. Scans were registered on the cranial base and were analyzed using point-to-point measurements, color-coded maps, and semitransparent overlays. Statistical tests included correlation and simple regression analysis. RESULTS: Pitch rotation, ranging from -2.2° to 2.2° (mean, 0.2°), was observed in clockwise and counterclockwise directions. Condylar sagittal displacement presented a positive correlation with OJ changes. Each millimeter of OJ correction resulted in an anterior condylar displacement of approximately 0.95 mm. Vertical condylar displacement correlated with OB changes and varied mostly between 2 mm and 4.5 mm. CONCLUSION: Immediately after HA insertion, no significant clockwise mandibular rotation was observed. The condyles were displaced anteriorly and inferiorly. Condylar anterior displacement and OJ correction presented a ratio close to 1:1. The vertical displacement of the condyles did not follow the same magnitude of OB changes.

16.
Angle Orthod ; 83(6): 994-1001, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23650959

RESUMEN

OBJECTIVE: To evaluate the coating thickness of four brands of as-received esthetic coated rectangular archwires and their surface characteristics and coating stability after 21 days of oral exposure compared to those of conventional stainless steel (SS) and nickel titanium (NiTi) ones. MATERIALS AND METHODS: The labial surface of the selected archwires was observed with a stereoscope and in a scanning electron microscope, and surface roughness was assessed with an atomic force microscope. The coating thickness of as-received wires and the percentage of coating lost on the labial surface of retrieved wires were measured using Image Pro Plus 4.5 software. RESULTS: All groups showed an average coating thickness of less than 0.002 inches. After oral exposure, archwires from two groups lost all coating on the labial surface. On average, 28.71% and 72.90% of the coating was lost in each of the other two groups, and the surface roughness of the remaining coating was higher than postclinical control wires. CONCLUSION: Coated archwires had a low esthetic value as they presented a nondurable coating. The remaining coating showed a severe deterioration and a greater surface roughness than postclinical control counterparts (conventional SS and NiTi wires).


Asunto(s)
Materiales Biocompatibles Revestidos/química , Estética , Níquel/química , Alambres para Ortodoncia , Resinas Sintéticas/química , Acero Inoxidable/química , Titanio/química , Análisis de Varianza , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Fotogrametría , Propiedades de Superficie
17.
Angle Orthod ; 83(1): 127-32, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22591261

RESUMEN

OBJECTIVE: To evaluate the color stability of six esthetic archwires at different time periods and their fluorescence. MATERIALS AND METHODS: Samples were evaluated after 7, 14, and 21 days of immersion in staining solution. Color measurements were performed by means of a spectrophotometer according to the Commission Internationale de I'Eclairage L*a*b* system, and color changes (ΔE*) and National Bureau of Standards units were computed. The fluorescence of as-received samples was evaluated by two observers and compared with that of a bovine central incisor. Statistical differences were investigated using analysis of variance and Tukey's post hoc test. RESULTS: All brands showed statistically significant color change after 21 days (ΔE* from 1.88 to 12.06). The Optis archwire (fiber-reinforced composite) presented the highest color alteration, although staining was observed only near its ends. The Trianeiro archwire (coated nickel-titanium) and the Ortho Organizers archwire (coated stainless steel) presented with less color change. The Optis archwire was the only one that presented with fluorescence similar to that of bovine teeth. CONCLUSIONS: All esthetic archwires assessed showed clinically noticeable color change after 21 days in staining solution. The optical properties of currently available esthetic archwires may not yet be ideal.


Asunto(s)
Color/normas , Fluorescencia , Alambres para Ortodoncia , Análisis de Varianza , Animales , Bovinos , Resinas Compuestas/química , Aleaciones Dentales/química , Ensayo de Materiales , Diseño de Aparato Ortodóncico , Espectrofotometría , Acero Inoxidable/química , Propiedades de Superficie
18.
Int J Dent ; 2012: 549761, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23209470

RESUMEN

Orthodontic implants have become a reliable method in orthodontic practice for providing temporary additional anchorage. These devices are useful to control skeletal anchorage in less compliant patients or in cases where absolute anchorage is necessary. There are a great number of advantages in this new approach which include easy insertion, decreased patient discomfort, low price, immediate loading, reduced diameter, versatility in the forces to be used, ease of cleaning, and ease of removal. However, a proper management of the screws by the practitioner is necessary in order to increase the success rate of the technique. The purpose of this paper is to update practitioners on the current concepts of orthodontic implants and orthodontic mechanics.

19.
Artículo en Inglés | MEDLINE | ID: mdl-22858019

RESUMEN

OBJECTIVE: This meta-analysis evaluated long-term dental and skeletal changes in patients submitted to surgically assisted rapid maxillary expansion. METHODS: A search was performed in electronic databases. Human clinical trials with patients submitted to surgically assisted rapid maxillary expansion with a follow-up of at least 1 year after expansion were selected. A methodological quality scoring process was used. A meta-analysis was performed to compare measurements of skeletal and dental structures. RESULTS: Three hundred sixty-five titles and abstracts were read. Ultimately 10 studies met the inclusion criteria. The 3 articles ranked as presenting low methodological quality were excluded. Three measurements could be compared and 3 time periods were used to assess changes. CONCLUSIONS: There is moderate evidence to conclude that maxillary alveolar width and intercanine and intermolar width have a long-term significant increase as a result of surgically assisted rapid maxillary expansion. A significant relapse is expected in the intercanine width after expansion.


Asunto(s)
Huesos/patología , Técnica de Expansión Palatina , Diente/patología , Humanos
20.
Angle Orthod ; 82(4): 739-47, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22149545

RESUMEN

A patient with an impacted dilacerated maxillary left central incisor is presented. The 8-year-old girl also presented with protrusion of teeth and lips, posterior crossbite, anterior open bite, thumb-sucking habit, and transposition of the maxillary left lateral incisor and canine. The treatment consisted of a multidisciplinary approach, including surgery, orthodontics, endodontics, and prosthodontics. The dilacerated incisor was surgically exposed, tractioned, endodontically treated, and restored. Four premolars were extracted to correct the protrusion. The outcome was the accomplishment of a balanced and functional occlusion, resulting in a pleasant smile.


Asunto(s)
Incisivo/cirugía , Maxilar/cirugía , Ortodoncia Correctiva/métodos , Traumatismos de los Dientes/complicaciones , Diente Impactado/terapia , Cefalometría , Niño , Dentición Mixta , Femenino , Humanos , Radiografía , Traumatismos de los Dientes/terapia , Diente Impactado/diagnóstico por imagen , Diente Impactado/etiología
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