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1.
Int J Comput Dent ; 24(2): 133-145, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34085499

RESUMO

AIM: The positional accuracy of bracket placement planned through tooth setup vs actual placement was evaluated by means of conventional thermoplastic indirect bonding trays and customized 3D-printed indirect bonding trays. MATERIALS AND METHODS: A total of 280 bracket positions placed on the crowns of 10 dental plaster models were evaluated. The manual setup method and a thermoplastic indirect bonding tray were used for the manual group. For the CAD/CAM group, the bracket was positioned using a digital setup and a corresponding 3D-printed tray. The positional accuracy of the bracket placement on the duplicated gypsum model using the trays was evaluated by means of 3D software. Six errors of bracket position (height, depth, mesiodistal, torque, rotation, and tip errors), including linear and angular errors, were measured. Differences in variables were compared across subgroups using the independent t test or the Mann-Whitney U test. RESULTS: Only the height error differed significantly (P < 0.05) between groups (manual: 0.2 mm; CAD/CAM: 0.12 mm). For both incisors and molars, the manual group showed significantly greater height errors than the CAD/CAM group (P < 0.05). The analysis of variance of the position error to the whole bracket showed statistically significant differences between tooth positions, linear measurements, and angular measurements (P < 0.05). CONCLUSION: A 3D-printed indirect bonding tray showed accuracy similar to that of conventional methods for bracket placement, with slightly greater bracket height accuracy. Further studies should strive to improve accuracy in terms of tooth positions.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Desenho Assistido por Computador , Modelos Dentários , Humanos , Impressão Tridimensional
2.
BMC Oral Health ; 21(1): 251, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33971859

RESUMO

BACKGROUND: In spite of the fact that fashion braces (FBs) have been in the spotlight in recent years among both orthodontists and the general public in several countries, there is still limited evidence regarding FBs. The aim was to identify health-related behaviors in using FBs by considering the Health Belief Model (HBM). METHODS: A cross-sectional study with a random sampling technique was conducted in Jazan, Saudi Arabia. The data was obtained from different middle and high schools students, and first-year students at Jazan University. The questionnaire collected data on demographic characteristics and 27 items to examine the constructs of the HBM. Chi Square test was carried out to establish the factors associated with using, the intention to use, and previous knowledge on the use of fashion braces. Logistic regression analysis was utilized to determine the factors associated with the use of fashion braces. RESULTS: 406 study participants completed the questionnaire with a response rate of 88.3%. Majority of respondents were males (52.2%) and > 19 years old (44.3%). Only 9.9% students had used the FBs. However, 25.7% of students had the intention to use them. The perceived susceptibility, perceived benefits and cues to action constructs scores were fair with the mean values of 15.38 (SD = 9.4), 28.17 (SD = 10.8) and 6.65 (SD = 2.50), respectively. However, the perceived barrier score was high with the mean values of 22.14 (SD = 7.50), and lower score of self-efficacy with mean of 8.73 (SD = 3.30). Gender, age, monthly income (family), and education level were significantly (p < 0.05) associated with the use of fashion braces among the study's participants. Based on the results of logistic regression analysis family income, perceived susceptibility, and risk severity constructs predict the use of fashion braces in the study's sample. CONCLUSIONS: The current study suggests that the family income, perceived susceptibility, and risk severity of students significantly influence the use of fashion braces. Hence, it is recommended that researchers should investigate effective educational strategies and programs for improving young people's knowledge about fashion braces and focus more on low family income students so that their using of fashion brace will be decreased.


Assuntos
Modelo de Crenças de Saúde , Braquetes Ortodônticos , Adolescente , Adulto , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Arábia Saudita , Adulto Jovem
3.
J Appl Oral Sci ; 29: e20201031, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33950080

RESUMO

METHODOLOGY: Fixed orthodontic appliances may lead to biofilm accumulation around them that may increase caries risk. This study aimed to evaluate the influence of quaternary ammonium methacrylates (QAMs) on the physicochemical properties, cytotoxicity, and antibacterial activity of adhesive resins for orthodontic purposes. A base resin was prepared with a comonomer blend and photoinitiator/co-initiator system. Two different QAMs were added to the base adhesive: dimethylaminododecyl methacrylate at 5 wt.% (DMADDM) or dimethylaminohexadecyl methacrylate (DMAHDM) at 10 wt.%. The base adhesive, without QAMs, (GC) and the commercial Transbond™ XT Primer 3M (GT) were used as control. The resins were tested immediately and after six months of aging in the water regarding the antibacterial activity and shear bond strength (SBS). The antibacterial activity was tested against Streptococcus mutans via metabolic activity assay (MTT test). The groups were also tested for the degree of conversion (DC) and cytotoxicity against keratinocytes. RESULTS: The resins containing QAM showed antibacterial activity compared to the commercial material by immediately reducing the metabolic activity by about 60%. However, the antibacterial activity decreased after aging (p<0.05). None of the groups presented any differences for SBS (p>0.05) and DC (p>0.05). The incorporation of DMADDM and DMAHDM significantly reduced the keratinocyte viability compared to the GT and GC groups (p<0.05). CONCLUSION: Both adhesives with QAMs showed a significant reduction in bacterial metabolic activity, but this effect decreased after water aging. Lower cell viability was observed for the group with the longer alkyl chain-QAM, without significant differences for the bonding ability and degree of conversion. The addition of QAMs in adhesives may affect the keratinocytes viability, and the aging effects maybe decrease the bacterial activity of QAM-doped materials.


Assuntos
Braquetes Ortodônticos , Antibacterianos , Biofilmes , Cimentos Dentários , Teste de Materiais , Metacrilatos , Cimentos de Resina , Streptococcus mutans
4.
Biomed Res Int ; 2021: 6663683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33959664

RESUMO

Objective: To compare the orthodontic bracket debonding force and assess the bracket failure pattern clinically between different teeth by a validated prototype debonding device. Materials and Method. Thirteen (13) patients at the end of comprehensive fixed orthodontic treatment, awaiting for bracket removal, were selected from the list. A total of 260 brackets from the central incisor to the second premolar in both jaws were debonded by a single clinician using a validated prototype debonding device equipped with a force sensitive resistor (FSR). Mean bracket debonding forces were specified to ten (10) groups of teeth. Following debonding, Intraoral microphotographs of the teeth were taken by the same clinician to assess the bracket failure pattern using a 4-point scale of adhesive remnant index (ARI). Statistical analysis included one-way ANOVA with post hoc Tukey HSD and independent sample t-test to compare in vivo bracket debonding force, Cohen's kappa (κ), and a nonparametric Kruskal-Wallis test for the reliability and the assessment of ARI scoring. Results: A significant difference (p < 0.001) of mean debonding force was found between different types of teeth in vivo. Clinically, ARI scores were not significantly different (p = 0.921) between different groups, but overall higher scores were predominant. Conclusion: Bracket debonding force should be measured on the same tooth from the same arch as the significant difference of mean debonding force exists between similar teeth of the upper and lower arches. The insignificant bracket failure pattern with higher ARI scores confirms less enamel damage irrespective of tooth types.


Assuntos
Cimentos Dentários/química , Remoção de Dispositivo , Braquetes Ortodônticos , Adulto , Falha de Equipamento , Humanos , Fenômenos Mecânicos , Dente/fisiologia , Adulto Jovem
5.
Biomed Res Int ; 2021: 6642254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33969121

RESUMO

Objective: This pre-post study is aimed at determining the effects of masticatory muscle activity (masseter and temporalis) measured via sEMG between conventional, self-ligating, and ceramic bracket after six months of orthodontic treatment. Methods: A total of eighteen (18) malocclusion patients were identified. Malocclusion patients were subdivided into 3 groups based on the bracket selection (conventional, self-ligating, and ceramic bracket) with 6 patients for each group. sEMG of muscles were done using a two-channel electromyography device, where pregelled and self-adhesive electrodes (bilateral) were applied. Chewing and clenching of masseter and temporalis muscle activity were recorded for 20 s pre and 6 months of orthodontic treatment using sEMG (frequency 60 Hz). The data were analysed by using repeated measures ANOVA in IBM SPSS Statistics Version 24.0. Results: Chewing and clenching for masseter muscle showed no significant difference (P > 0.05) in sEMG activity of three types of the brackets. However, for temporalis muscle, there was a significant difference found in sEMG activity during chewing (P < 0.05) and clenching (P < 0.05) between these three brackets. Conclusion: The activity of temporalis muscle showed significant changes in chewing and clenching, where the conventional group demonstrated better muscle activity pre and at six months of fixed appliances.


Assuntos
Eletromiografia , Músculo Masseter/fisiologia , Braquetes Ortodônticos , Músculo Temporal/fisiologia , Eletrodos , Feminino , Humanos , Masculino , Mastigação/fisiologia
6.
J Contemp Dent Pract ; 22(1): 27-33, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34002705

RESUMO

AIM: To evaluate the precision of the orthodontic bracket slot dimensions of 0.022 inch and to compare them with those of the manufacturers' specifications. MATERIALS AND METHODS: The slots of upper-right central incisor brackets (n = 5) from 11 commercial bracket systems of three different manufacturers (3M Unitek: Victory Mini Metal, Clarity, SmartClip, Clarity SL; ORMCO/SYBRON: Mini Diamond Twin, Damon Q, Damon Clear; Dentsply/GAC: Ovation, Mystique, In-Ovation R, In-Ovation C) were measured. The orthodontic brackets were scanned using micro-computed tomography (micro-CT), and the bracket slots were measured using micro-CT images. The slot was measured at four different surfaces (occlusal, gingival, base, and face) for both mesial and distal sites. Data were subjected to ANOVA and unpaired t-tests. A p-value of ≤0.05 was considered statistically significant. RESULTS: All brackets had slot dimensions that were significantly larger (p < 0.05) than the stated 0.022 inch. 3M-victory were 11.99% larger (0.02509 inch) and the closest to the stated dimension and the ORM-Damon C were 24.07% larger (0.02948 inch) than the quoted slot size of 0.022 inch. Comparison between mesial and distal sides showed that 91% of the bracket slots were asymmetrical at their bases and 100% asymmetrical at their faces. All of the bracket system showed divergent walls from base to face with values ranging from 1.96 (3M-SmartClip) to 26.58% (ORM-Damon C). CONCLUSION: The actual measurements of 11 bracket systems from three different manufacturers were more substantial than the manufacturers' specifications, and the walls of the slots diverged from the bracket bases in all of the tested bracket system. CLINICAL SIGNIFICANCE: Orthodontic bracket slots vary significantly from that of the manufacturers' specification. The orthodontist should anticipate such shortcomings and be able to modify treatment mechanics through additional wire bending in three spatial planes.


Assuntos
Braquetes Ortodônticos , Análise do Estresse Dentário , Teste de Materiais , Desenho de Aparelho Ortodôntico , Fios Ortodônticos , Aço Inoxidável , Microtomografia por Raio-X
7.
Biomed Res Int ; 2021: 6615560, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33987442

RESUMO

The purpose of this study was to evaluate the effect of metal orthodontic brackets on the accuracy of electronic apex locator (EAL). The actual canal lengths (ACL) of 40 mandibular incisor teeth were determined. Then, the teeth were randomly divided into two groups (n = 20). Orthodontic metal brackets were applied in the first group, and no brackets, in the second group. The working length of each tooth was measured with an EAL under 3 test conditions according to the distance between the lip clip and sample tooth. Data were analyzed using one-way repeated measures analysis of variance and Tukey's post hoc tests (p = 0.05). In the bracketed samples, when the lip clip was located at 1 cm and 2 cm from the samples. The mean differences between the EAL measurements and ACLs were statistically higher than those when the samples were located 3 cm from the lip clip (p < 0.05). There were also statistically significant differences between EAL measurements and ACLs in the bracketed samples located 1 and 2 cm from the lip clip (p < 0.05). In the nonbracketed group, the differences between EAL measurements and ACLs were not statistically significant in the samples located 1, 2, and 3 cm from the lip clip (p > 0.05). Use of orthodontic metal brackets can negatively influence the accuracy of the electronic apex locator when the distance between the lip clip and bracket was short. A minimum of 3 cm distance should be kept between the lip clip and tooth in order to make consistent electronic measurements.


Assuntos
Braquetes Ortodônticos , Ápice Dentário/anatomia & histologia , Eletrônica , Humanos , Projetos Piloto
8.
Dental Press J Orthod ; 26(2): e2119199, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008739

RESUMO

AIM: To assess the influence of elastomeric ligatures, subjected to a previous in vitro pigmentation process using different substances, on smile aesthetics during orthodontic treatment, from the perception of students and professionals. METHODS: Eight elastomeric ligatures of five commercial brands (3M/Unitek, American Orthodontics, Morelli, Ortho Technology, and Orthometric) (n=8) were immersed in coffee, Coca-Cola, and red wine for one minute per day, for 28 days; and another group of ligatures was immersed in artificial saliva. All samples were photographed and subsequently analyzed using the Adobe Photoshop software, by the RGB method. Afterwards, the pigmented ligatures were inserted in a patient wearing orthodontic brackets, and zoomed photographs of the smile were taken and presented to 40 evaluators, who filled in a satisfaction scale sheet to express their opinion on the smile aesthetics of each photograph. The color data were subjected to analysis of variance (ANOVA) and Tukey tests. RESULTS: The substance with the highest pigmentation potential was coffee (p< 0.05) followed by red wine (p< 0.05). Comparison among the brands used in this study showed that American Orthodontics and Orthometric had the lowest degree of pigmentation when immersed in coffee and red wine (p< 0.05), respectively. However, the brand that showed the highest level of satisfaction among the evaluators was Ortho Technology. CONCLUSIONS: The presence of pigmented elastomeric ligatures affected smile aesthetics, when compared with the control group.


Assuntos
Elastômeros , Braquetes Ortodônticos , Estética Dentária , Humanos , Teste de Materiais , Pigmentação
9.
Dental Press J Orthod ; 26(2): e211955, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008741

RESUMO

OBJECTIVE: To assess the color of different orthodontic resin bonding agents exposed to three antiseptic mouthrinses for a prolonged time interval (10-year aging simulation). METHODS: 160 specimens were distributed into four groups, according to the orthodontic resin bond agent (Concise, Transbond XT, Transbond Plus Color Change, and Natural Ortho). Each group was exposed to different antiseptic mouthrinses: alcohol-based (Listerine®), alcohol-free (Oral-B®), chlorhexidine (Periogard®) and distilled water as the control. Specimens were submitted to two cycles of staining and artificial aging. Color was evaluated by means of a digital spectrophotometer at the beginning of the experiment and after every cycle. The system used to assess color changes was the CIE L*a*b*. Data was analyzed using the ANOVA and Tukey post-hoc test. RESULTS: After simulation of 10 years of aging, Transbond XT and Natural Ortho composites presented no statistically significant differences in ∆E when exposed to different mouthrinses. The Concise composite specimens exposed to alcohol-free mouthrinse presented a significant difference when compared with specimens from the same group exposed to other antiseptic mouthrinses. Transbond Plus Color Change specimens exposed to chlorhexidine mouthrinse and to alcohol-containing mouthrinse presented a significant difference when compared with the specimens from the group exposed to water and alcohol-free antiseptic. CONCLUSION: All orthodontic resin bonding agents tested presented clinically perceptible color changes when exposed to at least one of the mouthrinses, except for the Natural Ortho composite. The Concise composite exposed to the alcohol-free solution was the resin that presented the highest color change values.


Assuntos
Anti-Infecciosos Locais , Braquetes Ortodônticos , Clorexidina , Resinas Compostas , Teste de Materiais , Antissépticos Bucais , Cimentos de Resina
10.
J Esthet Restor Dent ; 33(4): 668-674, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33899330

RESUMO

OBJECTIVE: To evaluate the color change and tooth whitening perception in 2 and 3 mm dental specimens simulating the orthodontic bracket for a 14-day period. MATERIALS AND METHODS: Forty bovine tooth fragments (8 × 7 mm) of 2 mm (G2, n = 20) and 3 mm (G3, n = 20) were divided into Control (C: without bracket simulation and whitening) and Experimental (E: with composite resin simulating orthodontic bracket cementation area). Analyses of color change (ΔE00 ) and perception of tooth whitening (WID ) were performed before (T0 ) and after (T1 ) the first bleaching session; before (T2 ) and after (T3 ) the second bleaching session; and after 7 days of the second bleaching session (T4 ). RESULTS: After 14 days (T4), ΔE00 and WID showed similarity results, except for G2C and G3E. The thickness did not influence the ΔE00 and WID (G2C = G3C and G2E = G3E). The presence of orthodontic bracket did not interfere in the color change or tooth whitening perception after 14 days, except for comparison of G2C and G3E. Additionally, dentin thickness did not influence the color change. CLINICAL SIGNIFICANCE: Teeth with orthodontic brackets showed similar color change and whitening perception to teeth without orthodontic bracket, but it is not influenced by dentin thickness.


Assuntos
Braquetes Ortodônticos , Clareadores Dentários , Clareamento Dental , Dente , Animais , Bovinos , Cor , Peróxido de Hidrogênio
11.
Eur J Oral Sci ; 129(2): e12772, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33829577

RESUMO

This study aimed to investigate the effect of universal adhesive and silane pretreatment on the bond durability of metal brackets to dental glass ceramics. Eighty lithium disilicate glass ceramic specimens were randomly assigned to one of four groups (n = 20) defined by the pretreatment and adhesive used: (i) Adper Single Bond 2; (ii) silane + Adper Single Bond 2; (iii) Single Bond Universal; and (iv) silane +Single Bond Universal. Maxillary central incisor metal brackets were bonded on the ceramic surfaces with resin composite. A shear bond strength test was conducted after 24 h of water storage and after 10,000 thermocycles. Adhesive remnant index scoring and field-emission scanning electron microscopy were performed to determine adhesives remaining on the ceramic surfaces and the ceramic ultrastructure following bracket debonding, respectively. After 10,000 thermocycles, specimens treated with Single Bond Universal preserved an appropriate bond strength between brackets and glass ceramics and showed minimum ceramic surface damage following bracket debonding, which was not the case in the other three groups. The application of a silane-containing universal adhesive without silane pretreatment achieves adequate durability of the bond of metal brackets to dental glass ceramics and allows safe debonding, which may aid in optimizing the effectiveness for orthodontic treatment.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Cerâmica , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Silanos , Propriedades de Superfície
12.
J Orthod ; 48(1): 13-23, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33843329

RESUMO

OBJECTIVES: To assess the transfer accuracy of three-dimensional (3D) printed transfer trays and compare them with transfer trays made up of polyvinyl siloxane (PVS) for use in indirect bonding. DESIGN: This was a two-arm parallel prospective randomised controlled trial. SETTING: The trial was undertaken at the outpatient department of a dental college. PARTICIPANTS: A total of 30 patients (18 men, 12 women) were randomly allocated to two groups. METHODS: The inclusion criteria included patients with permanent and fully erupted dentition (age range = 17-24 years), Angles class I malocclusion with crowding <3 mm requiring non-extraction treatment, good oral hygiene and no previous history of orthodontic treatment. Blinding was applicable only for outcome assessment. Indirect bonding was performed by the primary investigator for both the groups. Digital images of the pre-transfer and post-transfer brackets were obtained by means of an intra-oral scanner and compared using software. Superimpositions of pre- and post-transfer images were done to determine the transfer error for linear and angular variables for all tooth types. RESULTS: A total of 600 teeth were bonded, 300 each for both groups. Statistically significant differences were observed in all dimension between the two groups, with 3D-printed trays being more accurate than PVS trays except in the vertical dimension (P < 0.05). The prevalence of clinically unacceptable transfer errors revealed that most of the transfer errors were in the vertical dimensions for 3D-printed trays. CONCLUSION: 3D-printed trays are more accurate than PVS trays except for transfers in vertical dimension.


Assuntos
Colagem Dentária , Má Oclusão Classe I de Angle , Braquetes Ortodônticos , Adolescente , Adulto , Modelos Dentários , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
13.
Br Dent J ; 230(8): 495-496, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33893403
14.
Biomed Res Int ; 2021: 6634595, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816623

RESUMO

Background: Orthodontic patients are at high risk to develop caries. This study is introducing a clinical method detecting interfacial defects between ceramic brackets and enamel utilizing optical coherent tomography in addition to using the nanoleakage expression in vitro test. Methods: Transbond XT primer and moisture insensitive primer (MIP) were bonded to 75 human premolar enamel surfaces and divided into (XTD), (MIPD), and (MIPW) groups. The (XTD) and (MIPD) groups had ceramic brackets bonded to dry enamel surfaces using TransBond and moisture insensitive primers, respectively, while the (MIPW) samples were bonded to moist enamel using moisture insensitive primer. All specimens were examined under crosspolarization optical coherence tomography. Debonding forces of the brackets to 45 teeth (15 teeth/group). 30 bonded specimens (15 specimens/group) were cross-sectioned to detect the nanoleakage expression using scanning electron microscope equipped with energy-dispersive spectroscopy (SEM/EDS). The degree of conversion of the specimens in the experimental groups was tested using attenuated total reflectance Fourier transform infrared spectroscopy (FTIR/ATR). Results: Optical coherence tomography detected the interfacial defects between the ceramic brackets and tooth structure. One way ANOVA showed that (XTD) and (MIPD) groups recorded significantly higher bond strength values and less nanoleakage expression when compared to MIPW (p > 0.05). Conclusions: Optical coherence tomography can be utilized to detect interfacial adhesive-tooth defects. Dry enamel surfaces improve the quality of the enamel/primer interface (200 words).


Assuntos
Dente Pré-Molar , Esmalte Dentário , Braquetes Ortodônticos , Cimentos de Resina/química , Humanos , Resistência ao Cisalhamento , Espectrometria por Raios X
15.
Biomed Res Int ; 2021: 5544196, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33834066

RESUMO

Objectives: The aim of this study was to evaluate the protective effect of using four different fluoride bioactive enamel sealers against an acidic erosion challenge. Materials and Methods: A sample of 50 freshly extracted sound upper premolars had their buccal surface bonded to 50 orthodontic brackets using Transbond PLUS color change adhesive; the first four groups had four compositions of fluoride bioactive glasses based on 37 mol% SiO2, 43.9-53.9 mol% CaO, 6.1 mol% P2O5 and CaF2, and 0-10 mol% of Na2O applied to their surfaces and the fifth group served as control (which was not treated by any bioactive sealer). All specimens were challenged by 1% citric acid for 18 minutes which was stirred by a magnetic stirrer. The enamel surfaces next to the orthodontic brackets were examined by SEM. The Wilcoxon signed-rank test was used to compare the area covered by the fluoride bioactive pastes before/after erosion (p < 0.05). Samples from the layer formed on top of the examined teeth were tested before/after erosion to be examined by the attenuated total reflectance Fourier-transform infrared spectroscopy (FTIR/ATR). Results: The FTIR/ATR test showed that fluoride bioactive pastes' applications resulted in the formation of a hydroxyapatite-rich layer; the SEM analysis showed that the aforementioned layer significantly resisted erosion challenge when compared to the control group (p < 0.05). Conclusions: Fluoride bioactive pastes can efficiently protect the enamel surfaces next to orthodontic brackets from acidic erosion challenges.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Fluoretos/farmacologia , Vidro/química , Braquetes Ortodônticos , Substâncias Protetoras/farmacologia , Simulação por Computador , Cristalização , Esmalte Dentário/ultraestrutura , Selantes de Fossas e Fissuras , Resinas Sintéticas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
16.
Dental Press J Orthod ; 26(1): e2119150, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729290

RESUMO

INTRODUCTION: Third generation of LED light curing units might be used in short exposure periods for orthodontic brackets bonding. OBJECTIVE: This study evaluated the effect of the different radiant exposure (RE) values: Manufacturers' instructions (MI), ½ MI, 1/4 MI and Turbo mode. Two third-generation LED curing units were used: VALO® and Bluephase 20i® . The degree of conversion (DC) and Vickers hardness (VHN) of an orthodontic composite (OC) (Transbond XT) under metallic (MB) or ceramic brackets (CB) were measured. METHODS: OC was applied to the bracket base, which was then placed over an attenuated total reflectance (ATR) table coupled to an infrared light spectroscope, or to a glass surface for the VHN analysis. The specimens were light-cured and DC values were calculated. The VHN was obtained in a microhardness tester. The data were analyzed with 2-way ANOVA followed by Tukey's post-hoc test (pre-set α=0.05). Linear regression analysis evaluated the relationship between RE values and dependent variables. RESULTS: CB allowed higher DC and VHN values than MB (p< 0.001). No significant difference was noted among groups when CB were used. For MB, MI groups showed the highest DC and VHN values. A significant, but weak relationship was found between delivered RE values and dependent variables. CONCLUSIONS: The decrease in RE values from third generation LED CU did not jeopardize the DC values when CB were used, but can compromise DC and VHN values when MB are used.


Assuntos
Luzes de Cura Dentária , Braquetes Ortodônticos , Cerâmica , Resinas Compostas , Dureza , Teste de Materiais , Polimerização , Cimentos de Resina , Propriedades de Superfície
17.
Am J Orthod Dentofacial Orthop ; 159(5): 660-665, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33714568

RESUMO

INTRODUCTION: The objective of this study was to evaluate in vitro and in vivo bacterial endotoxin (LPS) adhesion in polyurethane and silicone esthetic elastomeric orthodontic ligatures. The null hypotheses tested were: (1) there is no LPS adhesion in esthetic elastomeric orthodontic ligatures; and (2) there is no difference in the LPS adhesion between different brands of these ligatures. METHODS: For the in vitro study, 4 types of esthetic elastomeric ligatures were used (Sani-Ties and Sili-Ties [Dentsply GAC, Islandia, NY;] and Mini Single Case Ligature Stick and Synergy low-friction ligatures [Rocky Mountain Orthodontics, Denver, Colo]), contaminated or not with endotoxin solution. Replicas of twisted wire and cast stainless steel ligatures were used as control. For the in vivo study, 10 male and 10 female patients, aged 15-30 years, received the same 4 types of ligatures, 1 of each inserted in the maxillary and mandibular canines, randomly. Twenty-one days later, the ligatures were removed, and endotoxin quantification was performed using the Limulus amebocyte lysate test. Data were analyzed (α = 0.05) using the Kruskal-Wallis test and Dunn's posttest or analysis of variance and Tukey's posttest. RESULTS: GAC silicone group had the lowest median contamination (1.15 endotoxin units/mL; P <0.0001) in vitro. In the in vivo study, the GAC silicone group had the lowest mean contamination (0.577 endotoxin units/mL; P <0.001). In both studies, the other groups did not present a significant difference when compared with each other (P >0.05). CONCLUSIONS: LPS exhibited an affinity for all the tested polyurethane and silicone elastomeric ligatures. GAC silicone ligatures presented with lower amounts of LPS attached to their surfaces. Thus, both null hypotheses were rejected.


Assuntos
Braquetes Ortodônticos , Adolescente , Adulto , Elastômeros , Endotoxinas , Estética Dentária , Feminino , Fricção , Humanos , Masculino , Teste de Materiais , Desenho de Aparelho Ortodôntico , Fios Ortodônticos , Aço Inoxidável , Adulto Jovem
18.
Medicina (Kaunas) ; 57(2)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671217

RESUMO

Background and objectives: The aim of this study was to evaluate the influence of friction on design of the type of bracket, patients' perception of pain and the impact on their oral health-related quality of life. Materials and Methods: A randomized clinical trial was carried out with 90 patients (62.2% women and 37.8% men) with three kinds of fixed multi-bracket appliances: Conventional (GC), fixed multi-bracket low friction (GS) and self-ligating (GA). The VAS (Visual Analogue Scale) was used to determine pain during the first seven days of treatment at different points in time. The patients were also given the OHIP-14 (Oral Health Impact Profile) questionnaire to analyse their oral health-related quality of life (OHRQoL) after the first 30 days of treatment. The ANOVA test was used for the analysis of the variables and the post hoc Bonferroni test for the comparison between groups. Results: Maximum pain was observed between one and two days after the start of treatment. The GC group showed the greatest degree of pain, with maximum values (4.5 ± 2.0) at 24 h. The self-ligation brackets show lower impact on patients' oral health-related quality of life (0.8 ± 2.2, p < 0.01). Conclusions: Friction in the type of bracket influences pain and the Oral Health-Related Quality of Life of patients who use multi-bracket fixed orthodontics.


Assuntos
Braquetes Ortodônticos , Qualidade de Vida , Fricção , Humanos , Teste de Materiais , Desenho de Aparelho Ortodôntico , Fios Ortodônticos
19.
BMC Oral Health ; 21(1): 84, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627113

RESUMO

BACKGROUND: The mechanism of gingival growth that may occur during fixed orthodontic treatment is not yet fully understood and the amount of dental plaque is often incriminated. The objective of this study was to evaluate the prevalence of gingival growth during multi-attachment orthodontic treatment and to prioritize its predicting factors, especially the quantity of biofilm. METHODS: This comprehensive cross-sectional descriptive study was conducted on orthodontic patients aged 9 to 30 years, in good health, treated by a fixed appliance. Periodontal clinical parameters such as plaque index, gingival index, probing pocket depth, periodontal phenotype and gingival enhancement index were recorded. Likewise, the brushing habits and the date of the last scaling were noted. The orthodontic parameters studied were the duration of the treatment, the type of bracket, the alloys used for the arches and the type of ligatures. Descriptive statistics were carried out, and variables presenting p value < 0.25 were included in a multivariate analysis to calculate the Odds Ratio (OR) of gingival enlargement". RESULTS: A total of 193 patients were included (16.38 ± 4.89 years). Gingival growth occurred for 49.7% of patients included. The predisposing factors for this pathology during fixed orthodontic treatment were conventional metal brackets (p = 0.021), mouth breathing (p = 0.040), male gender (p = 0.035), thick periodontal phenotype (p = 0.043), elastomeric ligations (p = 0.007), duration of treatment (p = 0.022) and presence of plaque (p = 0.004). After achievement of the logistic regression, only two factors remained related to gingival enlargement: metallic brackets (OR: 3.5, 95% CI: 1.1-10.55) and duration of treatment (OR: 2.03, 95% CI: 1.01-4.08). The amount of plaque would not be directly related to the development of gingival increase during orthodontic treatment. CONCLUSIONS: Among the predisposing factors that underlie gingival growth during multi-attachment therapy, the amount of plaque is not found. The qualitative assessment of the plaque and its evolution during treatment could clarify the role of the biofilm in the occurrence of gingival overgrowth.


Assuntos
Placa Dentária , Hiperplasia Gengival , Braquetes Ortodônticos , Adolescente , Adulto , Biofilmes , Causalidade , Criança , Estudos Transversais , Índice de Placa Dentária , Humanos , Masculino , Braquetes Ortodônticos/efeitos adversos , Adulto Jovem
20.
Br Dent J ; 230(4): 189, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33637907
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