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1.
PLoS One ; 15(9): e0239759, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32970759

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the effects of miniscrew insertion angle and vertical facial type on the interradicular miniscrew-root distance available for molar distalization. MATERIALS AND METHODS: Cone-beam computed tomography images of 60 adults with skeletal Class I occlusion exhibiting hyperdivergent (n = 20), normodivergent (n = 20), and hypodivergent (n = 20) facial types were used. Placement of a 6-mm long, 1.5-mm diameter, tapered miniscrew was simulated at a site 4 mm apical to the cementoenamel junction, with insertion angles of 0°, 30°, 45°, and 60° relative to the transverse occlusal plane. The shortest linear distance between the miniscrew and anterior root at four interradicular sites was measured: maxillary second premolar and first molar (Mx 5-6), maxillary first and second molars (Mx 6-7), mandibular second premolar and first molar (Mn 5-6), and mandibular first and second molars (Mn 6-7). RESULTS: Miniscrew-root distance significantly increased as the insertion angle increased from 0° to 60°. In the mandible, the distances significantly differed among vertical facial types, increasing in the following order: hyperdivergent, normodivergent, and hypodivergent. The minimum mean distance was found in the Mx 6-7 (30°; 0.86±0.35 mm), and the maximum mean distance was found in the Mn 5-6 (60°; 2.64±0.56 mm). The rates of miniscrews located buccally outside the root distalization path were up to 70% and 55% when the miniscrews were placed at 60° insertion angles in the Mx 5-6 and Mn 5-6 regions, respectively. CONCLUSIONS: Miniscrew-root distance increased significantly with the increased insertion angle, and the amount of increase was affected by the miniscrew placement site and vertical facial type. To ensure adequate distalization of the posterior segment, the miniscrew should be inserted at an angle in the interradicular area between the second premolar and first molar.


Asunto(s)
Tornillos Óseos , Simulación por Computador , Tomografía Computarizada de Haz Cónico/métodos , Diente Molar/diagnóstico por imagen , Métodos de Anclaje en Ortodoncia/métodos , Técnicas de Movimiento Dental/métodos , Raíz del Diente/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Métodos de Anclaje en Ortodoncia/instrumentación , Técnicas de Movimiento Dental/instrumentación
2.
Acta Odontol Latinoam ; 33(2): 69-81, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920608

RESUMEN

The aim of this study was to evaluate changes in periodontal status and maxillary buccal bone by considering clinical and tomographic parameters during the first year of orthodontic expansion with Invisalign® aligners. Upper first (1PM) and upper second (2PM) premolars of 19 patients with orthodontic expansion requirement treated with Invisalign® aligners were evaluated. Plaque index (PI), gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL) and cone beam tomographic (CBCT) records were collected at 76 sites before starting treatment (T0) and at 12 months (T1). Bone height was measured from cementoenamel junction (CEJ) to the crest cortical bone (CC). Bone thickness was measured at two levels: 4 mm (CEJ+4) and 6 mm (CEJ+6) apical to the CEJ. A descriptive analysis was made of the variations of bone thickness and height in a series of cases. The average expansion was 1.93 mm for 1PM and 167 mm for 2PM. Arithmetic mean of distance CEJ-CC in 1PM was 3.05 mm at T0, and remained at 3.05 mm at T1. Arithmetic mean of distance CEJ-CC in 2PM was 2.06 mm at T0 and 2.31 at T1. Post-expansion, most of the analyzed sites (86%) exhibited a bone thickness of ≥0.5 mm. The greatest variations between T0 and T1 were observed at the level of 1PM CEJ+ 4 and 2PM CEJ+ 6. The minimal changes in the clinical records (GI, PI, PPD and CAL) between T0 and T1 were compatible with the maintenance of gingivalperiodontal health. Invisalign® for expansion movements did not produce substantial changes in the evaluated periodontal clinical parameters or in the bone measurements. Removable appliances reduce plaque retentive factors and favor adequate oral hygiene.


Asunto(s)
Placa Dental/etiología , Maloclusión/terapia , Maxilar/diagnóstico por imagen , Salud Bucal , Aparatos Ortodóncicos Removibles/efectos adversos , Técnicas de Movimiento Dental/efectos adversos , Tomografía Computarizada de Haz Cónico , Placa Dental/microbiología , Índice de Placa Dental , Estado de Salud , Humanos , Técnicas de Movimiento Dental/instrumentación
3.
Acta Odontol Latinoam ; 33(2): 112-116, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920613

RESUMEN

Orthodontics with low friction, low force, passive self-ligating brackets produces alveolar-dental remodeling, resulting in an increase in the transverse diameter of the dental arches, especially in the premolar sector. The aim of this study was to compare the modifications of the transverse diameter in the pre- and post-dental alignment cast models with orthodontics with passive self-ligating brackets in patients with moderate to severe dental discrepancy. The study included 28 patients of both sexes aged 16 to 48 years with dental discrepancies between -6 and -16 mm, treated with self-ligating Damon brackets and thermally activated Nickel- Titanium-Copper arches. With a digital pachymeter, Mitutoyo brand, five measurements were taken per dental arch: distance between canines (C), first premolars (1PM), second premolars (2 PM), first molars (1M) and second molars (2M), before and after orthodontic alignment. The variations were statistically evaluated by Student T Test for paired samples. Average distance between teeth varied with dental alignment in both jaws. The greatest increases in transverse diameter were recorded in the premolar areas. Minor though statistically significant variations also occurred in the 2M of the maxilla and in the C of the mandible In alignment with passive self-ligating brackets, there is an increase in the transverse diameter due to the development of the dental arches, mainly in the premolar sector of both jaws and also at the level of the canines in the mandible.


Asunto(s)
Diseño de Aparato Ortodóncico , Soportes Ortodóncicos , Cierre del Espacio Ortodóncico/instrumentación , Técnicas de Movimiento Dental/instrumentación , Adolescente , Adulto , Diente Premolar/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
4.
BMC Oral Health ; 20(1): 114, 2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32299416

RESUMEN

BACKGROUND: Increased tooth mobility persists after fixed orthodontic appliance removal, which is therapeutically utilized for post-treatment finishing with positioners. As such a fine adjustment is only required for selected teeth, the aim of this pilot study was to investigate tooth mobility in vivo on corrected and uncorrected subgroups under positioner therapy. METHODS: Mobility was measured on upper teeth of 10 patients (mean age 16.8) by applying loadings for 0.1, 1.0 and 10.0 s with a novel device directly after multibracket appliance debonding as much as 2d, 1, 2 and 6 weeks later. Positioners were inserted at day 2. Specimens were divided into Group C (teeth corrected via positioner), Group N (uncorrected teeth adjacent to teeth from group C), and Group U (uncorrected teeth in an anchorage block). Untreated individuals served as controls (n = 10, mean age 22.4). Statistics were performed via Kolmogorov-Smirnov test and Welch's unequal variances t-test for comparisons between groups. P < 0.05 was considered statistically significant. RESULTS: After 1 week, tooth mobility in Group U almost resembled controls (13.0-15.7 N), and reached physiological values after 6 weeks (17.4 N vs. 17.3 N in controls). Group C (9.0-13.4 N) and Group N (9.2-14.7 N) maintained increased mobility after 6 weeks. Tooth mobility was generally higher by reason of long loading durations (10.0 s). CONCLUSIONS: Positioner therapy can selectively utilized increased tooth mobility upon orthodontic fixed appliance treatment for case refinements. Here, uncorrected teeth in anchorage blocks are not entailed by unwanted side effects and recover after 6 weeks post treatment. Corrected teeth and their neighbors exhibit enhanced mobility even after 6 weeks, which represents a necessity for the proper correction of tooth position, and concurrently arouses the requirement for an adequate retention protocol.


Asunto(s)
Métodos de Anclaje en Ortodoncia/instrumentación , Aparatos Ortodóncicos Fijos , Movilidad Dentaria/diagnóstico , Técnicas de Movimiento Dental/instrumentación , Adulto , Humanos , Lactante , Proyectos Piloto , Diente , Adulto Joven
5.
J Vis Exp ; (158)2020 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-32338652

RESUMEN

The center of resistance (CRES) is regarded as the fundamental reference point for predictable tooth movement. The methods used to estimate the CRES of teeth range from traditional radiographic and physical measurements to in vitro analysis on models or cadaver specimens. Techniques involving finite element analysis of high-dose micro-CT scans of models and single teeth have shown a lot of promise, but little has been done with newer, low-dose, and low resolution cone beam computed tomography (CBCT) images. Also, the CRES for only a few select teeth (i.e., maxillary central incisor, canine, and first molar) have been described; the rest have been largely ignored. There is also a need to describe the methodology of determining the CRES in detail, so that it becomes easy to replicate and build upon. This study used routine CBCT patient images for developing tools and a workflow to obtain finite element models for locating the CRES of maxillary teeth. The CBCT volume images were manipulated to extract three-dimensional (3D) biological structures relevant in determining the CRES of the maxillary teeth by segmentation. The segmented objects were cleaned and converted into a virtual mesh made up tetrahedral (tet4) triangles having a maximum edge length of 1 mm with 3matic software. The models were further converted into a solid volumetric mesh of tetrahedrons with a maximum edge length of 1 mm for use in finite element analysis. The engineering software, Abaqus, was used to preprocess the models to create an assembly and set material properties, interaction conditions, boundary conditions, and load applications. The loads, when analyzed, simulated the stresses and strains on the system, aiding in locating the CRES. This study is the first step in accurate prediction of tooth movement.


Asunto(s)
Análisis de Elementos Finitos , Imagenología Tridimensional/métodos , Diente/fisiología , Tomografía Computarizada de Haz Cónico , Modelos Dentales , Humanos , Maxilar/diagnóstico por imagen , Programas Informáticos , Diente/diagnóstico por imagen , Técnicas de Movimiento Dental/instrumentación
6.
J Appl Oral Sci ; 28: e20190364, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32348442

RESUMEN

Objective Maxillary molar distalization with intraoral distalizer appliances is a non-extraction orthodontic treatment used to correct molar relationship in patients with Class II malocclusion presenting maxillary dentoalveolar protrusion and minor skeletal discrepancies. This study compares the changes caused by three distalizers with different force systems. Methodology 71 patients, divided into three groups, were included. The Jones jig group (JJG, n=30; 16 male, 14 female, 13.17 years mean age) was treated with the Jones jig for 0.8 years. The Distal jet group (DJG, n=25; 8 male, 17 female, 12.57 years mean age) was treated with the Distal jet for 1.06 years. The First Class group (FCG, n=16; 6 male, 10 female, 12.84 years mean age) was treated with the First Class for 0.69 years. Intergroup treatment changes were compared using one-way ANOVA, followed by post-hoc Tukey's tests. Results Intergroup comparisons showed significantly greater maxillary incisor protrusion in DJG than in FCG (2.56±2.24 mm vs. 0.74±1.39mm, p=0.015). The maxillary first premolars showed progressive and significantly smaller mesial angulation in JJG, FCG and DJG, respectively (14.65±6.31º, 8.43±3.99º, 0.97±3.16º; p<0.001). They also showed greater mesialization in JJG than FCG (3.76±1.46 mm vs. 2.27±1.47 mm, p=0.010), and greater extrusion in DJG compared to JJG (0.90±0.77 mm vs 0.11±0.60 mm, p=0.004). The maxillary second premolars showed progressive and significantly smaller mesial angulation and mesialization in JJG, FCG and DJG, respectively (12.77±5.78º, 3.20±3.94º, -2.12±3.71º and 3.87±1.34 mm, 2.25±1.40 mm, 1.24±1.26 mm, respectively; p<0.001). DJG showed smaller distal angulation of maxillary first molars (-2.14±5.09º vs. -7.73±4.28º and -6.05±3.76º, for the JJG and FCG, respectively; p<0.001) and greater maxillary second molars extrusion (1.17±1.41 mm vs -0.02±1.16 mm and 0.16±1.40 mm, for the JJG and FCG, respectively; p=0.003). Overjet change was significantly larger in DJG compared to FCG (1.79±1.67 mm vs 0.68±0.84; p=0.046). Treatment time was smaller in FCG (0.69±0.22 years vs 0.81±0.33 years and 1.06±0.42 years, comparing it with the JJG and DJG, respectively; p=0.005). Conclusion The three appliances corrected the Class II molar relationship by dentoalveolar changes. The Distal jet produced smaller molar distal angulation than the Jones jig and First Class. The First Class appliance showed less anchorage loss, greater percentage of distalization and shorter treatment time than the Jones jig and Distal jet.


Asunto(s)
Maloclusión de Angle Clase II/terapia , Diente Molar/fisiopatología , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos Fijos , Técnicas de Movimiento Dental/instrumentación , Adolescente , Análisis de Varianza , Cefalometría , Niño , Femenino , Humanos , Masculino , Maloclusión de Angle Clase II/fisiopatología , Métodos de Anclaje en Ortodoncia/instrumentación , Valores de Referencia , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del Tratamiento
7.
BMC Oral Health ; 20(1): 70, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32164665

RESUMEN

BACKGROUND: The ability of a loop to generate a certain moment/force ratio (M/F ratio) can achieve the desired tooth movement in orthodontics. The present study aimed to investigate the effects of elastic modulus, cross-sectional dimensions, loop configuration geometry dimensions, and activation force on the generated M/F ratio of vertical, L- and T-loops. METHODS: A total of 120 three-dimensional loop models were constructed with the Solidworks 2017 software and used for simulating loop activation with the Abaqus 6.14 software. Six vertical loop variations, 9 L-loop variations, and 9 T-loop variations were evaluated. In each group, only one parameter was variable [loop height, ring radius, leg length, leg step distance, legs distance, upper length, different archwire materials (elastic modulus), cross-sectional dimension, and activation force]. RESULTS: The simulation results of the displacement and von Mises stress of each loop were investigated. The maximum displacement in the height direction was recorded to calculate the M/F ratio. The quantitative change trends in the generated M/F ratio of the loops with respect to various variables were established. CONCLUSIONS: Increasing the loop height can increase the M/F ratio of the loop. This increasing trend is, especially, much more significant in T-loops compared with vertical loops and L-loops. In vertical loops, increasing the ring radius is much more effective than increasing the loop height to increase the M/F ratio of the loop. Compared with SS, TMA archwire loops can generate a higher M/F ratio due to its lower elastic modulus. Loops with a small cross-sectional area and high activation force can generate a high M/F ratio. The introduction of a leg step to loops does not increase the M/F ratio of loops.


Asunto(s)
Análisis de Elementos Finitos , Diseño de Aparato Ortodóncico , Alambres para Ortodoncia/estadística & datos numéricos , Técnicas de Movimiento Dental/instrumentación , Análisis del Estrés Dental , Humanos , Estrés Mecánico
8.
J Biol Regul Homeost Agents ; 34(6 Suppl. 2): 21-36, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33541062

RESUMEN

Use of the so-called distalizing mechanics is a common treatment to correct class II malocclusion. One of the first appliances made for molar distalization was the pendulum, which resulted immediately efficient. The knowledge of pendulum efficacy, in regards to distalizing treatment in adolescence, has guided the research to analyze pendulum effect in childhood: checking the pre-eruptive, natural and distal movement of upper second premolar following first upper molar distalization in order to obtain an advance resolution on Angle's Class II patient, limited treatment time, reduced periodontal inflammation and stress on permanent teeth root. A pilot study testing the possibility of a prospective study was necessary on 6 patients treated following an accurate protocol (6 months and 1-year Rx control) and 6 patient control after one year. Statistical analysis by T-Test was done. Oral hygiene controls every month were done. Second upper bicuspid vertical (1.6mm) and sagittal (2.5mm) movement mean values allow to emphasize a distal variation of tooth axis inclination of treatment group than control group, and a second upper bicuspid distal departure from "gubernaculus dentis" of second deciduous molar in treated patients. Periodontal inflammation appears inexistent on second and first upper premolar germs after the comparison between RX exam of treatment and control groups because of exploiting deciduous teeth. Besides periodontal inflammation and teeth root stress on first upper molar of treatment group, after RX analysis, results were limited compared to control groups because of the advanced orthodontic interceptive treatment during a previous stage of first upper molar root development.


Asunto(s)
Maloclusión de Angle Clase II/terapia , Aparatos Ortodóncicos , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Adolescente , Niño , Humanos , Maloclusión de Angle Clase II/cirugía , Maxilar/cirugía , Diente Molar/cirugía , Proyectos Piloto , Estudios Prospectivos
9.
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1101287

RESUMEN

Abstract Objective: To evaluate the rate of tooth movement and the pain perception via self-ligating (SL) and conventional elastomeric ligation brackets (CB) system. Material and Methods: This study has been conducted at the Orthodontic Department of Baqai Dental College, Baqai Medical University. The sample size of this study comprised 40 patients, falling between the age of 12-30 years without any sex discrimination. Shapiro-Wilk was used to check the distribution of data. Non-parametric Mann Whitney U test was applied to evaluate the pain associated with SL and CB brackets system. To analysis the canine retraction Wilcoxon test was applied for the comparison of CB and SL brackets system. For all statistical analyses, the p-value of <0.05 was considered significant. Results: Pain level associated with retraction via CB and SL shows significant differences. However, the rate of canine retraction via CB and SL shows no significant differences at stages T0-T1 and T1-T2. However, stage T2-T3 shows a significant difference. Conclusion: As pain during orthodontic treatment is mostly associated with the level of compression of the periodontal ligament, it may be hypothesized that lower frictional forces generate less compression of the periodontal ligament and blood vessels, and so alter the type of pain experienced.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Ligamento Periodontal , Técnicas de Movimiento Dental/instrumentación , Métodos de Anclaje en Ortodoncia/instrumentación , Percepción del Dolor , Fricción Ortodóntica , Estadísticas no Paramétricas , Malasia
10.
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1101285

RESUMEN

Abstract Objective: To investigate the expression of High Mobility Group Box 1 (HMGB1) and Heat Shock Protein-70 (HSP-70) during orthodontic tooth movement (OTM) after (-)- Epigallocatechin-3-Gallate (EGCG) in East Java Green Tea (Camelia Sinensis) Methanolic Extract (GTME) administration in vivo. Material and Methods: 28 Wistar rats (Rattus Novergicus) was used and divided into 4 groups accordingly: K- without EGCG and OTM; K+ with OTM, without EGCG for 14 days; T1with OTM for 14 days and EGCG for 7 days; treatment group 2 (T2) with OTM and EGCG for 14 days. OTM animal model was achieved through the installation of the OTM device by means of NiTi close coil spring with 10g force placed between the first incisor and first maxillary molars. The samples were terminated on Day 14. The pre-maxillary was isolated for the immunohistochemical examination. Analysis of Variance (ANOVA) then continued with Tukey Honest Significant Difference (HSD) (p<0.05) was performed to analyze the data. Results: The highest HMGB1 and HSP-70 expression were found in the K+ group pressure side, meanwhile the lowest HMGB1 and HSP-70 expression were found in K- group tension side in the alveolar bone. There was a significant decrease of HMGB1 and HSP-70 expression in T2 compared to T1 and K+ with significant between groups (p<0.05; p=0.0001). Conclusion: The decreased expression of HMGB1 and HSP-70 in alveolar bone of OTM wistar rats due to post administration of GTME that consisted EGCG.


Asunto(s)
Animales , Ratas , Técnicas de Movimiento Dental/instrumentación , Ratas Wistar , Proteína HMGB1 , Proteínas de Choque Térmico , Antioxidantes/uso terapéutico , , Huesos , Inmunohistoquímica , Análisis de Varianza , Modelos Animales , Incisivo , Indonesia , Diente Molar
11.
J. appl. oral sci ; 28: e20190364, 2020. tab, graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1101252

RESUMEN

Abstract Objective Maxillary molar distalization with intraoral distalizer appliances is a non-extraction orthodontic treatment used to correct molar relationship in patients with Class II malocclusion presenting maxillary dentoalveolar protrusion and minor skeletal discrepancies. This study compares the changes caused by three distalizers with different force systems. Methodology 71 patients, divided into three groups, were included. The Jones jig group (JJG, n=30; 16 male, 14 female, 13.17 years mean age) was treated with the Jones jig for 0.8 years. The Distal jet group (DJG, n=25; 8 male, 17 female, 12.57 years mean age) was treated with the Distal jet for 1.06 years. The First Class group (FCG, n=16; 6 male, 10 female, 12.84 years mean age) was treated with the First Class for 0.69 years. Intergroup treatment changes were compared using one-way ANOVA, followed by post-hoc Tukey's tests. Results Intergroup comparisons showed significantly greater maxillary incisor protrusion in DJG than in FCG (2.56±2.24 mm vs. 0.74±1.39mm, p=0.015). The maxillary first premolars showed progressive and significantly smaller mesial angulation in JJG, FCG and DJG, respectively (14.65±6.31º, 8.43±3.99º, 0.97±3.16º; p<0.001). They also showed greater mesialization in JJG than FCG (3.76±1.46 mm vs. 2.27±1.47 mm, p=0.010), and greater extrusion in DJG compared to JJG (0.90±0.77 mm vs 0.11±0.60 mm, p=0.004). The maxillary second premolars showed progressive and significantly smaller mesial angulation and mesialization in JJG, FCG and DJG, respectively (12.77±5.78º, 3.20±3.94º, -2.12±3.71º and 3.87±1.34 mm, 2.25±1.40 mm, 1.24±1.26 mm, respectively; p<0.001). DJG showed smaller distal angulation of maxillary first molars (-2.14±5.09º vs. -7.73±4.28º and -6.05±3.76º, for the JJG and FCG, respectively; p<0.001) and greater maxillary second molars extrusion (1.17±1.41 mm vs -0.02±1.16 mm and 0.16±1.40 mm, for the JJG and FCG, respectively; p=0.003). Overjet change was significantly larger in DJG compared to FCG (1.79±1.67 mm vs 0.68±0.84; p=0.046). Treatment time was smaller in FCG (0.69±0.22 years vs 0.81±0.33 years and 1.06±0.42 years, comparing it with the JJG and DJG, respectively; p=0.005). Conclusion The three appliances corrected the Class II molar relationship by dentoalveolar changes. The Distal jet produced smaller molar distal angulation than the Jones jig and First Class. The First Class appliance showed less anchorage loss, greater percentage of distalization and shorter treatment time than the Jones jig and Distal jet.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Técnicas de Movimiento Dental/instrumentación , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos Fijos , Maloclusión de Angle Clase II/terapia , Diente Molar/fisiopatología , Valores de Referencia , Cefalometría , Reproducibilidad de los Resultados , Estudios Retrospectivos , Análisis de Varianza , Resultado del Tratamiento , Métodos de Anclaje en Ortodoncia/instrumentación , Maloclusión de Angle Clase II/fisiopatología
12.
Int Orthod ; 17(4): 806-816, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31477527

RESUMEN

The treatment of skeletal deep bite does not remain stable. The patient was a Japanese woman aged 16 years and 10 months. Her chief complaint was maxillary protrusion. The degree of overjet was + 10.5 mm and overbite was + 5.0 mm; the intermolar relationship was Angle Class II. An excessive curve of Spee was observed in the mandibular arch. A hypodivergent skeletal pattern was indicated by a small mandibular plane angle and gonial angle. The maxillary incisors were proclined and the mandibular incisors were retroclined. Based on the above findings, the patient was diagnosed with Angle Class II maxillary protrusion and deep bite with hypodivergency. Both maxillary first premolars were extracted and orthodontic treatment was performed using multi-bracket appliances. A proper overbite was achieved by 5.0 mm intrusion of the mandibular incisors. The maxillary incisors were retracted by 11.2 mm and a proper overjet was achieved. Good treatment results were obtained without apical root resorption. After 2 years of retention, the occlusion has been well maintained. This report may constitute a remarkable suggestion for treatment of an unstable deep bite.


Asunto(s)
Incisivo , Maloclusión de Angle Clase II/terapia , Maxilar , Métodos de Anclaje en Ortodoncia/métodos , Sobremordida/terapia , Técnicas de Movimiento Dental/métodos , Adolescente , Diente Premolar , Cefalometría , Modelos Dentales , Oclusión Dental , Femenino , Humanos , Maloclusión de Angle Clase II/diagnóstico por imagen , Mandíbula , Métodos de Anclaje en Ortodoncia/instrumentación , Soportes Ortodóncicos , Alambres para Ortodoncia , Sobremordida/diagnóstico por imagen , Técnicas de Movimiento Dental/instrumentación , Resultado del Tratamiento
13.
Int Orthod ; 17(4): 817-825, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31481304

RESUMEN

This case report shows the orthodontic treatment of four first premolar extractions of a 14-year-old teenager presenting a dental Class I malocclusion with a severe retrognathic mandible. It reflects conflicting views on objectives between the orthodontist who takes into account the facial balance and the patient who only desires a tooth alignment.


Asunto(s)
Diente Premolar/cirugía , Maloclusión de Angle Clase II/terapia , Maloclusión de Angle Clase I/terapia , Extracción Dental , Técnicas de Movimiento Dental/métodos , Adolescente , Puntos Anatómicos de Referencia , Cefalometría , Modelos Dentales , Mentoplastia , Humanos , Masculino , Maloclusión de Angle Clase I/diagnóstico por imagen , Maloclusión de Angle Clase II/diagnóstico por imagen , Aparatos Ortodóncicos Fijos , Alambres para Ortodoncia , Osteotomía , Técnicas de Movimiento Dental/instrumentación , Resultado del Tratamiento
14.
Am J Orthod Dentofacial Orthop ; 156(3): 312-325, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31474261

RESUMEN

INTRODUCTION: This aim of this paper is to describe and identify the practitioner and patient characteristics that are associated with treatment recommendations for adult anterior open bite patients across the United States. METHODS: Practitioners and patients were recruited within the framework of the National Dental Practice-Based Research Network. Practitioners were asked about their demographic characteristics and their treatment recommendations for these patients. The practitioners also reported on their patients' dentofacial characteristics and provided initial cephalometric scans and intraoral photographs. Patients were asked about their demographic characteristics, previous orthodontic treatment, and goals for treatment. Four main treatment groups were evaluated: aligners, fixed appliances, temporary anchorage devices (TADs), and orthognathic surgery. Extractions were also investigated. Predictive multivariable models were created comparing various categories of treatment as well as extraction/nonextraction decisions. RESULTS: Ninety-one practitioners (mostly orthodontists) and 347 patients were recruited from October 2015 to December 2016. Increased aligner recommendations were associated with white and Asian patients, the presence of tongue habits, and female practitioners. TADs were recommended more often in academic settings. Recommendations for orthognathic surgery were associated with demographic factors, such as availability of insurance coverage and practitioner race/ethnicity, and dentofacial characteristics, such as anteroposterior discrepancies, more severe open bites, and steeper mandibular plane angles. Extraction recommendations were largely associated with severe crowding and incisor proclination. CONCLUSIONS: Both doctor and patient demographic factors, as well as dentofacial characteristics, were significantly associated with treatment recommendations for adult anterior open bite patients.


Asunto(s)
Mordida Abierta/terapia , Ortodoncia Correctiva/estadística & datos numéricos , Ortodoncistas/estadística & datos numéricos , Pautas de la Práctica en Odontología/estadística & datos numéricos , Anciano , Cefalometría , Femenino , Humanos , Incisivo , Masculino , Mandíbula , Persona de Mediana Edad , Mordida Abierta/diagnóstico por imagen , Mordida Abierta/epidemiología , Aparatos Ortodóncicos/estadística & datos numéricos , Ortodoncia Correctiva/instrumentación , Ortodoncia Correctiva/métodos , Procedimientos Quirúrgicos Ortognáticos , Encuestas y Cuestionarios , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Técnicas de Movimiento Dental/estadística & datos numéricos , Estados Unidos/epidemiología
15.
Am J Orthod Dentofacial Orthop ; 156(3): 326-336, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31474262

RESUMEN

INTRODUCTION: Orthodontic mini-implants aid in the correction of distocclusions via direct anchorage (pull from mini-implant to teeth) and indirect anchorage (teeth pulled against other teeth anchored by the mini-implant). The aim of this study was to compare stress levels on the periodontal ligament (PDL) of maxillary buccal teeth in direct and indirect distalization against orthodontic mini-implants and accounting for individual variation in maxillary anatomy and biomechanical characteristics of the compact bone. METHODS: A 3D model of the maxilla containing the different components (teeth, PDL, trabecular and cortical bones) was generated from a computed tomographic scan. Cortical bone was divided into several areas according to previously defined zones. Bone stiffness and thickness data, obtained from 11 and 12 cadavers, respectively, were incorporated into the initial model to simulate the individual cortical bone variation at the different locations. Subsequently, a finite element analysis was used to simulate the distalization modalities. RESULTS: Stresses at the buccal, palatal, mesial, and distal surfaces were significantly different between adjacent teeth under stiffness but not thickness variation. In both distalization modalities, low or no significant correlations were found between stress values and corresponding cortical bone thicknesses. High significant and inverted correlations were observed at the first molar between stress amounts and cortical bone stiffness (direct modality: -0.68 < r < -0.72; indirect modality: -0.80 < r < -0.82; P <0.05). CONCLUSIONS: With the use of a novel finite element approach that integrated human data on variations in bone properties, findings suggested that cortical bone stiffness may influence tooth movement more than bone thickness. Significant clinical implications could be related to these findings.


Asunto(s)
Análisis del Estrés Dental/métodos , Análisis de Elementos Finitos , Técnicas de Movimiento Dental/métodos , Fenómenos Biomecánicos , Tornillos Óseos , Simulación por Computador , Implantes Dentales , Humanos , Imagenología Tridimensional/métodos , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Modelos Anatómicos , Diente Molar , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Diseño de Aparato Ortodóncico , Ligamento Periodontal , Estrés Mecánico , Técnicas de Movimiento Dental/instrumentación , Torsión Mecánica
16.
Am J Orthod Dentofacial Orthop ; 156(3): 401-411, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31474270

RESUMEN

A 24-year-old man presented with a severe skeletal class III malocclusion, associated with an anterior and posterior crossbite in the left side, upper and lower lip eversion, skeletal asymmetry, midline discrepancy, diastemas in the maxillary and mandibular dental arches, and agenesis of maxillary lateral incisors and canines with retained deciduous teeth. Treatment was performed with the use of the Win Lingual System. When the 0.016 × 0.022-inch NiTi archiwire was applied, the deciduous teeth were extracted and replaced with temporary crowns connected to the appliance. After the aligning, leveling, and diastema closure phases, a modified Le Fort II osteotomy, a mandibular setback with a bilateral sagittal split osteotomy and a genioplasty were performed. Implants were placed in the canine site through a flapless guided surgery, and cantilevered temporary bridges were delivered. Final prosthetic rehabilitation included veneers for the central incisors and zirconia-ceramic cantilevered bridges for the canine and lateral incisors. After 36 months of active treatment, the patient showed an Angle Class I molar and canine relationship and an ideal overbite and overjet. His profile had improved, lips were competent, and gingival levels were acceptable. The lateral radiograph and cephalometric analysis showed a good balance of the skeletal pattern, a good profile of the soft tissue, and proper inclinations of the maxillary and mandibular incisors in relation to maxilla and mandible. After 2 years of follow-up, the patient had a pleasant smile and no relapse, or joint or muscular pain.


Asunto(s)
Anodoncia/complicaciones , Maloclusión de Angle Clase III/terapia , Diseño de Aparato Ortodóncico/instrumentación , Diseño de Aparato Ortodóncico/métodos , Aparatos Ortodóncicos , Adulto , Cefalometría , Diente Canino , Implantación Dental Endoósea , Implantes Dentales , Modelos Dentales , Diastema/cirugía , Diastema/terapia , Estética Dental , Humanos , Incisivo , Labio , Masculino , Maloclusión de Angle Clase I/complicaciones , Maloclusión de Angle Clase III/diagnóstico por imagen , Maloclusión de Angle Clase III/rehabilitación , Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Maxilar/cirugía , Diente Molar , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Soportes Ortodóncicos , Alambres para Ortodoncia , Osteotomía , Sobremordida/terapia , Radiografía Panorámica , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Adulto Joven
17.
Am J Orthod Dentofacial Orthop ; 156(2): 210-219, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31375231

RESUMEN

INTRODUCTION: More patients are choosing customized orthodontic appliances because of their excellent esthetics. It is essential that clinicians understand the biomechanics of the tooth movement tendency in customized lingual orthodontics. This study aimed to evaluate the tooth movement tendency during space closure in maxillary anterior teeth with the use of miniscrew anchorage in customized lingual orthodontics with various power arm locations. METHODS: Three-dimensional finite element models of the maxilla were created with miniscrews and power arms; the positions were varied to change the force directions. A retraction force (1.5 N) was applied from the top of the miniscrews to the selected points on the power arm, and the initial displacements of the reference nodes of the maxillary teeth were analyzed. RESULTS: After applying force in different directions, power arms located at the distal side of the canines led to larger initial lingual crown tipping and occlusal crown extrusion of the maxillary incisors compared with power arms located at the midpoint between the lateral incisors and canines, and caused a decreasing trend of the intercanine width. CONCLUSIONS: In customized lingual orthodontic treatment, power arms located at the distal side of the canines are unfavorable for anterior teeth torque control and intercanine width control. Power arms located at the midpoint between the lateral incisors and canines can get better torque control, but still cannot achieve excepted torque without extra torque control methods, no matter whether its force application point is higher than, lower than, or equal to the level of the top of the miniscrews.


Asunto(s)
Tornillos Óseos , Análisis de Elementos Finitos , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Cierre del Espacio Ortodóncico , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Adulto , Fenómenos Biomecánicos , Simulación por Computador , Diente Canino/patología , Humanos , Imagenología Tridimensional/métodos , Incisivo/patología , Maxilar , Modelos Biológicos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos , Soportes Ortodóncicos , Cierre del Espacio Ortodóncico/instrumentación , Cierre del Espacio Ortodóncico/métodos , Alambres para Ortodoncia , Planificación de Atención al Paciente , Estrés Mecánico , Corona del Diente , Torque , Resultado del Tratamiento
18.
Int Orthod ; 17(3): 415-424, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31255550

RESUMEN

INTRODUCTION: The purpose of this study was to systematically review the evidence regarding conventional versus skeletal anchorage devices for molar distalization. METHOD: An electronic search was conducted. Hand searching was done in the reference lists of included studies and some journals. Studies comparing conventional and skeletal anchorage for molar distalization in Angle class I or II malocclusions were assessed. Presence of periodontal disease, second or third molar extraction and application of tooth accelerating methods led to exclusion of studies. Generic-inverse variance approach was used for meta-analysis by use of the mean difference and random-effect model. Risk of bias was evaluated in included studies. RESULTS: A total of 1996 articles were found; of which, 1991 were excluded. The mean amounts of molar distalization/tipping in skeletal anchorage and conventional anchorage groups were 5.35mm/8.44° and 4.25mm/8.31°, respectively, which were not significantly different. The mean amounts of premolar movement in skeletal anchorage and conventional anchorage groups were -0.96mm and +2.21mm, respectively, which was statistically significant (P=0.004). Duration of treatment in skeletal anchorage and conventional anchorage groups was 8.23 months and 7.95 months, respectively, which were significantly different (P=0.0001). Risk of bias was assessed to be high. CONCLUSION: The conventional and skeletal anchorage devices were not significantly different in terms of the amount of molar distalization/tipping. However, the anchorage loss was lower in the skeletal anchorage group. The treatment time was shorter in the conventional anchorage group. More studies with proper design are required.


Asunto(s)
Maxilar , Diente Molar , Métodos de Anclaje en Ortodoncia/instrumentación , Técnicas de Movimiento Dental/instrumentación , Diente Premolar , Bases de Datos Factuales , Arco Dental , Humanos , Maloclusión de Angle Clase I , Maloclusión de Angle Clase II , Métodos de Anclaje en Ortodoncia/métodos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos
19.
Am J Orthod Dentofacial Orthop ; 156(1): 148-156, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31256828

RESUMEN

This article reports on the technical aspects of using a computer-aided design-computer-aided manufacturing (CAD-CAM) insertion guide for the placement of orthodontic mini-implants used for the purpose of providing anchorage support for maxillary molar distalization. A 10-year-old girl presented with a bilateral full-step Angle Class II molar relationship in the permanent dentition, with anterior arch-length insufficiency and blocked out maxillary canine teeth. The primary treatment objective was to provide an esthetic and functional occlusal outcome, and secondarily to avoid the removal of multiple premolar teeth. The patient was initially treated with an implant-supported distalization device, and the occlusion was subsequently detailed with preadjusted fixed orthodontic appliances. The CAD-CAM procedure facilitates the safe and precise insertion of mini-implants in the anterior palate, potentially broadening the scope of use of palatal mini-implants for less experienced clinicians. The illustrated protocol allows for the insertion of mini-implants and fitting of a prefabricated appliance in a single office appointment.


Asunto(s)
Tornillos Óseos , Diseño Asistido por Computadora , Implantes Dentales , Maloclusión de Angle Clase II/terapia , Métodos de Anclaje en Ortodoncia/métodos , Diseño de Aparato Ortodóncico/métodos , Técnicas de Movimiento Dental/métodos , Diente Premolar , Cefalometría/métodos , Niño , Diente Canino , Modelos Dentales , Dentición Permanente , Estética Dental , Femenino , Humanos , Maloclusión de Angle Clase II/diagnóstico por imagen , Maloclusión de Angle Clase II/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Diente Molar , Métodos de Anclaje en Ortodoncia/instrumentación , Diseño de Aparato Ortodóncico/instrumentación , Aparatos Ortodóncicos Fijos , Alambres para Ortodoncia , Paladar (Hueso)/diagnóstico por imagen , Paladar (Hueso)/cirugía , Planificación de Atención al Paciente , Técnicas de Movimiento Dental/instrumentación , Resultado del Tratamiento
20.
Am J Orthod Dentofacial Orthop ; 156(1): 75-86, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31256844

RESUMEN

INTRODUCTION: Maintaining tooth anchorage during orthodontic treatment has challenged orthodontists and threatening the success of some orthodontic therapy. The objective of this study was to evaluate the effect of local administration of simvastatin on orthodontic tooth movement. METHODS: Nickel-titanium coil springs were used to induce orthodontic tooth movement in 10 white New Zealand rabbits for 21 days. A split-mouth design was implemented where one mandibular quadrant received local administration of simvastatin and the corresponding mandibular quadrant received control vehicle solution on a weekly basis. Magnitudes of tooth movement were measured on 3-dimensional models of the experimental teeth. Animals were killed at the end of the experimental period to allow histomorphometric analysis of alveolar bone modeling. RESULTS: The total magnitude of tooth movement in the quadrant receiving simvastatin was significantly less than that in the quadrant receiving control vehicle solution. Local administration of simvastatin resulted in a significant percentage of inhibition of tooth movement of 39.8 ± 22.6%. Histomorphometric analysis revealed a significant reduction in the numbers of osteoclasts and areas of active bone-resorptive lacunae hindering bone resorption processes in the quadrant receiving simvastatin. CONCLUSIONS: Local administration of simvastatin can reduce the rate and magnitude of orthodontic tooth movement. Moreover, local administration of simvastatin diminishes bone resorption processes associated with orthodontic tooth movement reducing the number of osteoclasts and the subsequent area of active bone resorption.


Asunto(s)
Resorción Ósea/patología , Osteoclastos/efectos de los fármacos , Simvastatina/administración & dosificación , Simvastatina/antagonistas & inhibidores , Técnicas de Movimiento Dental/métodos , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/patología , Animales , Remodelación Ósea/efectos de los fármacos , Resorción Ósea/diagnóstico por imagen , Masculino , Mandíbula/irrigación sanguínea , Mandíbula/efectos de los fármacos , Mandíbula/patología , Modelos Animales , Níquel/química , Aparatos Ortodóncicos , Alambres para Ortodoncia , Osteoclastos/patología , Conejos , Titanio/química , Técnicas de Movimiento Dental/instrumentación
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