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1.
Arch Oral Biol ; 128: 105170, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34082374

RESUMEN

OBJECTIVE: The aim of this study was to quantify the temporal changes in inflammation and TRPA1, TRPV1 and CGRP expression in the trigeminal ganglion during force-induced orthodontic pain. DESIGN: Orthodontic force was applied to both maxillary first molars in 8-week-old Wistar rats for 12 h, 24 h, 3 d or 7 d. The rat grimace scale (RGS) score and duration of face grooming were used to measure orthodontic pain. Western blotting was performed to assess TRPA1, TRPV1 and CGRP expression in trigeminal ganglia. NF-кB levels and colocalization of TRPA1, TRPV1 and CGRP were evaluated by immunofluorescent staining. RESULTS: Application of continuous force significantly increased pain behaviours at 1 and 3 d. NF-кB significantly increased in periodontal ligament at 12 h until 3 d. TRPV1 was significantly elevated within 1 d; TRPA1 significantly increased from 1-3 d; CGRP expression significantly increased from 12 h to 3 d. The TRPV1/TRPA1 expression ratio was highest at 12 h; the TRPA1/TRPV1 ratio peaked at 3 d. The percentages of trigeminal neurons co-expressing TRPA1/TRPV1, TRPA1/CGRP, and TRPV1/CGRP significantly increased by 12 h and peaked at 24 h. CGRP expression had a stronger positive correlation with TRPV1 than TRPA1. CONCLUSIONS: Inflammation induced by application of orthodontic force sensitizes trigeminal TRPV1 and TRPA1; TRPV1 is primarily activated as an early response, whereas TRPA1 is activated as a late response. Activation of both nociceptors results in CGRP release. Thus, blocking both TRPV1 and TRPA1 may represent a primary therapeutic target for relief of orthodontic pain.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina , Dolor , Canal Catiónico TRPA1 , Canales Catiónicos TRPV , Técnicas de Movimiento Dental/efectos adversos , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Ratas , Ratas Wistar , Canal Catiónico TRPA1/metabolismo , Canales Catiónicos TRPV/metabolismo , Ganglio del Trigémino/metabolismo
2.
Dental Press J Orthod ; 26(2): e2119378, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33950082

RESUMEN

OBJECTIVE: To determine whether separating the alignment and leveling phases can reduce proclination of the mandibular incisors. METHODS: Eligibility criteria included Class I subjects with an irregularity index of 3-5 mm, 3-4 mm curve-of-Spee (COS), and non-extraction treatment. Thirty adults were randomly allocated into two groups: (1) Control group was leveled and aligned simultaneously with flat archwires progressively to 0.016x0.022-in stainless-steel; (2) Experimental group was aligned first with 0.014-in-superelastic NiTi with mild accentuated COS, then leveled using 0.016x0.022-in beta-titanium accentuated COS archwires and gradually reduced the curve until flat. Mandibular incisor position and inclination were evaluated by cephalometric analysis. COS and irregularity index were evaluated in study models. Assessment was conducted twice after 0.016-in NiTi and after 0.016x0.022-in stainless-steel archwire placements. Dental changes from cephalograms and models were compared within group using paired t-test and between groups using independent t-test. RESULTS: Control group: Round-wire-phase, mandibular incisors tipped labially (4.38° and 1 mm) with intrusion (-1.13 mm); Rectangular-wire-phase, mandibular incisors further intruded and proclined (-0.63 mm and 1.38°). Experimental group: During aligning with round accentuated COS archwires, mandibular incisors tipped very slightly labially (0.75° and 0.50 mm) with no significant intrusion; during leveling with rectangular archwires, incisors majorly intruded (1.75 mm) with slight proclination (1.81°). The experimental group had significant less incisor proclination (control: 5.76°, experimental: 2.56°) with more incisor intrusion (control: -1.75 mm, experimental: -2.13 mm). The COS in experimental group showed significant greater reduction (-2.88 mm) than that of the control group (-1.69 mm). CONCLUSION: In control group, mandibular incisor proclination was markedly observed in round archwires, with further proclination caused by rectangular archwires. In experimental group, minimal proclination was exhibited when accentuated COS round archwires were used for aligning. Leveling with rectangular archwires caused less proclination with more COS reduction.


Asunto(s)
Incisivo , Técnicas de Movimiento Dental , Cefalometría , Mandíbula , Alambres para Ortodoncia , Acero Inoxidable
3.
Prog Orthod ; 22(1): 12, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33937947

RESUMEN

BACKGROUND: The purpose of this study was to compare the stress distribution and displacement patterns of the one versus two maxillary molars distalization with iPanda and to evaluate the biomechanical effect of distalization on the iPanda using the finite element method. METHODS: The finite element models of a maxillary arch with complete dentition, periodontal ligament, palatal and alveolar bone, and an iPanda connected to a pair of midpalatal miniscrews were created. Two models were created to simulate maxillary molar distalization. In the first model, the iPanda was connected to the second molar to simulate a single molar distalization. In the second model, the iPanda was connected to the first molar to simulate "en-masse" first and second molar distalization. A varying force from 50 to 200 g was applied. The stress distribution and displacement patterns were analyzed. RESULTS: For one molar, the stress was concentrated at the furcation and along the distal surface in all roots with a large amount of distalization and distobuccal crown tipping. For two molars, the stress in the first molar was 10 times higher than in the second molar with a great tendency for buccal tipping and a minimal amount of distalization. Moreover, the stress concentration on the distal miniscrew was six times higher than in the mesial miniscrew with an extrusive and intrusive vector, respectively. CONCLUSIONS: Individual molar distalization provides the most effective stress distribution and displacement patterns with reduced force levels. In contrast, the en-masse distalization of two molars results in increased force levels with undesirable effects in the transverse and vertical direction.


Asunto(s)
Maloclusión Clase II de Angle , Diseño de Aparato Ortodóncico , Cefalometría , Análisis de Elementos Finitos , Humanos , Maxilar , Diente Molar , Técnicas de Movimiento Dental
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(3): 362-367, 2021 Jun 01.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-34041888

RESUMEN

With a case of mesial impaction of maxillary first and second molar, the mechanical analysis and clinical applications of a self-made helical spring for the uprighting treatment of mesial impacted molars was introduced.


Asunto(s)
Técnicas de Movimiento Dental , Diente Impactado , Humanos , Mandíbula , Maxilar , Diente Molar , Tercer Molar
6.
J Appl Oral Sci ; 29: e20200791, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34008748

RESUMEN

BACKGROUND: IGF-1 may be an important factor in bone remodeling, but its mechanism of action on osteoclasts during orthodontic tooth movement is complex and unclear. METHODOLOGY: The closed-coil spring was placed between the left maxillary first molar and upper incisors with a force of 50 g to establish an orthodontic movement model. Eighty SD rats were randomized to receive phosphate buffer saline or 400 ng rhIGF-1 in the lateral buccal mucosa of the left maxillary first molar every two days. Tissue sections were stained for tartrate-resistant acidic phosphatase (TRAP), the number of TRAP-positive cells was estimated and tooth movement measured. RESULTS: The rhIGF-1 group exhibited evidential bone resorption and lacuna appeared on the alveolar bone compared to the control group. Moreover, the number of osteoclasts in compression side of the periodontal ligament in the rhIGF-1 group peaked at day 4 (11.37±0.95 compared to 5.28±0.47 in the control group) after the orthodontic force was applied and was significantly higher than that of the control group (p<0.01). Furthermore, the distance of tooth movement in the rhIGF-1 group was significantly larger than that of the control group from day 4 to day 14 (p<0.01), suggesting that rhIGF-1 accelerated orthodontic tooth movement. CONCLUSION: Our study has showed that rhIGF-1 could stimulate the formation of osteoclasts in the periodontal ligament, and accelerate bone remodeling and orthodontic tooth movement.


Asunto(s)
Osteoclastos , Técnicas de Movimiento Dental , Animales , Remodelación Ósea , Humanos , Factor I del Crecimiento Similar a la Insulina , Ligamento Periodontal , Ratas , Ratas Sprague-Dawley
7.
J Vis Exp ; (170)2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33938887

RESUMEN

Orthodontic tooth movement is a complex biological process of altered soft and hard tissue remodeling as a result of external forces. In order to understand these complex remodeling processes, it is critical to study the tooth and periodontal tissues within their 3D context and therefore minimize any sectioning and tissue artefacts. Mouse models are often utilized in developmental and structural biology, as well as in biomechanics due to their small size, high metabolic rate, genetics and ease of handling. In principle this also makes them excellent models for dental related studies. However, a major impediment is their small tooth size, the molars in particular. This paper is aimed at providing a step by step protocol for generating orthodontic tooth movement and two methods for 3D imaging of the periodontal ligament fibrous component of a mouse mandibular molar. The first method presented is based on a micro-CT setup enabling phase enhancement imaging of fresh collagen tissues. The second method is a bone clearing method using ethyl cinnamate that enables imaging through the bone without sectioning and preserves endogenous fluorescence. Combining this clearing method with reporter mice like Flk1-Cre;TdTomato provided a first of its kind opportunity to image the 3D vasculature in the PDL and alveolar bone.


Asunto(s)
Imagenología Tridimensional/métodos , Mandíbula/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Ligamento Periodontal/diagnóstico por imagen , Técnicas de Movimiento Dental , Animales , Fenómenos Biomecánicos , Cinamatos , Modelos Animales de Enfermedad , Ratones , Microtomografía por Rayos X/métodos
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(2): 434-436, 2021 Feb 22.
Artículo en Chino | MEDLINE | ID: mdl-33879922

RESUMEN

In recent years, developing new methods to accelerate orthodontic tooth movement (OTM) has attracted extensive attention in the field of orthodontic clinical and scientific research. It reduces orthodontic treatment time and risks. Over the past, various approaches have been done to accelerate orthodontic tooth movement. Several forms of corticotomy techniques have been effective in inducing rapid tooth movement. These techniques activate regional acceleratory phenomenon and create a favorable microenvironment for accelerating tooth movement. Root resorption is one of most common side effects of orthodontic treatment. It affects the long-term viability and health of teeth. However, the effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption still remains unclear. Accelerating tooth movement may have two-side effects on root resorption. Through shortening the treatment period and removing the hyalinized tissues, the acceleration of orthodontic tooth movement could reduce root resorption. The increase of root resorption might be due to the local inflammation and function of cementoclasts/odontoclasts. In this paper, we reviewed the effects of different corticotomy techniques accelerating orthodontic tooth movement on root resorption. Corticotomy techniques deal with mucoperio-steal flaps and bone tissues differently and develop towards minimally invasive. Previous studies on root resorption use two-dimensional images, including apical films and panoramic tomography, to evaluate the degree of root resorption. In recent years, researches measure the volume of root resorption accurately using cone-beam computed tomography (CBCT) and micro-CT. Most studies suggest that the root resorption during acceleration of orthodontic tooth movement through corticotomy techniques is not statistically different from that of traditional orthodontic treatment. Some studies using micro-CT have shown that the root resorption in the groups of corticotomy techniques increases compared with the control group without surgery. Because of the short duration of these studies, the clinical significance is controversial on the overall impact of corticotomy techniques on orthodontic treatment. Accelerating orthodontic tooth movement is still at its emerging phase and need further research in the form of clinical trials to illustrate the effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption.


Asunto(s)
Resorción Radicular , Técnicas de Movimiento Dental , Tomografía Computarizada de Haz Cónico , Humanos , Osteoclastos , Resorción Radicular/etiología , Raíz del Diente , Microtomografía por Rayos X
11.
Sensors (Basel) ; 21(5)2021 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-33799930

RESUMEN

BACKGROUND: In the dental field, digital technology has created new opportunities for orthodontists to integrate their clinical practice, and for patients to collect information about orthodontics and their treatment, which is called "teledentistry." Dental monitoring (DM) is a recently introduced orthodontic application that combines safe teledentistry with artificial intelligence (AI) using a knowledge-based algorithm, allowing an accurate semi-automatic monitoring of the treatment. Dental Monitoring is the world's first SaaS (Software as a Service) application designed for remote monitoring of dental treatment, developed in Paris, France, with Philippe Salah as the Co-founder and CEO. CASES PRESENTATION: This report describes two cases in which DM system was essential to achieve the control of certain movements: it was possible to follow the movement, even if complex, such as the anterior cross of an adult patient and a lack of space in the canine of the growing patient. The software analyzed the fit and retention of the aligner, thus ensuring correct biomechanics. They were treated during the COVID-19 pandemic lockdown with aligners. The first case is a growing patient who was monitored during an interceptive orthodontic treatment to manage a retained upper canine. The second case is an adult patient forced to finalize his treatment of upper lateral incisor crossbite. The software analyzed the fit and retention of the aligner, thus ensuring correct biomechanics. CONCLUSIONS: DM system appears to be a promising method, useful for improving the interaction between doctor and patient, generally acceptable and useful to patients, even in critical clinical situations, at least in cases with optimal compliance and ability to use the tool properly.


Asunto(s)
Inteligencia Artificial , Diseño de Aparato Ortodóncico , Programas Informáticos , Telemedicina , Técnicas de Movimiento Dental , Adulto , COVID-19 , Control de Enfermedades Transmisibles , Francia , Humanos , Pandemias
12.
J Appl Oral Sci ; 29: e20200734, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33825762

RESUMEN

OBJECTIVE: To compare tooth movement rate and histological responses with three different force magnitude designs under osteoperforation in rabbit models. METHODOLOGY: 48 rabbits were divided into three groups: Group A, Group B, and Group C, with traction force of 50 g, 100 g, 150 g, respectively. Osteoperforation was performed at the mesial of the right mandibular first premolar, the left side was not affected. One mini-screw was inserted into bones between two central incisors. Coil springs were fixed to the first premolars and the mini-screw. Tooth movement distance was calculated, and immunohistochemical staining of PCNA, OCN, VEGF, and TGF-ß1 was analyzed. RESULTS: The tooth movement distance on the surgical side was larger than the control side in all groups (P<0.01). No significant intergroup difference was observed for the surgical side in tooth movement distance among the three groups (P>0.05). For the control side, tooth movement distance in Group A was significantly smaller than Groups B and C (P<0.001); no significant difference in tooth movement distance between Group B and Group C was observed (P>0.05). On the tension area of the moving premolar, labeling of PCNA, OCN, VEGF and TGF-ß1 were confirmed in alveolar bone and periodontal ligament in all groups. PCNA, OCN, VEGF and TGF-ß1 on the surgical side was larger than the control side in all groups (P<0.001). CONCLUSION: Osteoperforation could accelerate orthodontic tooth movement rate in rabbits. Fast osteoperforation-assisted tooth movement in rabbits was achieve with light 50 g traction.


Asunto(s)
Ligamento Periodontal , Técnicas de Movimiento Dental , Animales , Diente Premolar , Conejos
15.
17.
Shanghai Kou Qiang Yi Xue ; 30(1): 23-27, 2021 Feb.
Artículo en Chino | MEDLINE | ID: mdl-33907774

RESUMEN

PURPOSE: To investigate the effect of ipriflavone on reconstruction of periodontal tissues during recurrence of orthodontic teeth. METHODS: Twenty-four male SD rats were randomized into 2 groups, ipriflavone group(IP group) and control group, there were 12 rats in each group. The model of recurrence after movement of orthodontic teeth in rats was established. After continuous loading for 10 days, the loading devices were removed. Rats in ipriflavone group (IP group) were given ipriflavone intragastrically for 10 mg/(kg·d) after the devices were removed, while rats in the control group were given an equivalent amount of normal saline after the devices were removed. On the 0th, 1st, 3rd, 7th, and 10th day of administration, the rat maxillary impression and plaster model of two groups were prepared under local anesthesia, the distance between maxillary first molar lingual sulcus point and third molar in lingual groove point was measured to evaluate the relapse distance. After drug infusion for 10 days, the collected tissue specimens were stained with H-E to observe periodontal reconstruction, and expression of bone morphogenetic protein-2(BMP-2) was detected by immunohistochemical staining. Software Image-Pro 6.0 was used to analyze the optical density values of the stained sections. The data were analyzed with SPSS 22.0 software package. RESULTS: After removing the orthopaedic devices for 10 days , there was a significant recurrence of the movement of the orthodontic teeth in both groups. The recurrent distance of IP group was significantly smaller than that of the control group, and still significantly smaller than that of the control group at 10 d. H-E staining and immunohistochemical staining results showed that the IP group had more new bone formation and more BMP-2 expression in the periodontal tissues compared to the control group in vivo. CONCLUSIONS: In the process of recurrence of orthodontic tooth movement, ipriflavone can promote the expression of BMP-2 in periodontal tissue, improve bone remodeling of periodontal tissue, and effectively reduce the recurrent rate of orthodontic tooth movement.


Asunto(s)
Periodoncio , Técnicas de Movimiento Dental , Animales , Isoflavonas , Masculino , Ligamento Periodontal , Ratas , Ratas Sprague-Dawley , Recurrencia
18.
Shanghai Kou Qiang Yi Xue ; 30(1): 38-43, 2021 Feb.
Artículo en Chino | MEDLINE | ID: mdl-33907777

RESUMEN

PURPOSE: To explore the effect of tooth movement on lower incisors of rabbits with thin and thick aligners. METHODS: A group of 6 male New Zealand rabbits were randomly divided into 2 groups, the experimental group(n=3) was designed to move the lower incisors distally by 3 steps with thin and thick aligners(0.625 and 0.75 mm),0.33 mm each;the control group (n=3) was designed to move the teeth by 3 steps with aligner of conventional thickness (0.75 mm), 0.20 mm each. Polyvinyl siloxane impressions were taken before and after aligner placement. The data of tooth movement were measured. SPSS 19.0 software package was used for statistical analysis. RESULTS: The accuracy of tooth movement expression in both groups decreased gradually from the incisal part to the gingival part. The rate of tooth movement in the experimental group was significantly higher than that of the control group(P<0.001). CONCLUSIONS: The tooth movement of rabbit mandibular central incisor was tipping with the clear aligner. The rate of tooth movement was increased by applying thin and thick aligners,but the accuracy of tooth movement was decreased.


Asunto(s)
Incisivo , Técnicas de Movimiento Dental , Animales , Masculino , Conejos
19.
Br Dent J ; 230(7): 397, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33837333
20.
J Indian Soc Pedod Prev Dent ; 39(1): 104-105, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33885397

RESUMEN

Anchorage control during the correction of severely crowded dentitions has always been a source of concern during orthodontic therapy. The Nance palatal arch (NPA) has, in the past, been widely used for reinforcing anchorage in such cases. Modifications of the NPA have been reported for use as a fixed functional appliance or for molar distalization. Herein, a simple, effective modification of the conventional NPA is introduced incorporating two power arms, which can be used for unravelling of anterior crowding at the same time effectively augmenting molar anchorage.


Asunto(s)
Maloclusión Clase II de Angle , Diseño de Aparato Ortodóncico , Cefalometría , Humanos , Diente Molar , Técnicas de Movimiento Dental
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