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1.
J Clin Pediatr Dent ; 44(6): 451-458, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33378466

RESUMEN

OBJECTIVE: The surface roughness of various orthodontic materials could affect biofilm formation and friction. The purpose of this study was to examine the surface roughness and chemical composition of the slots and wings of several ceramic self-ligating brackets. STUDY DESIGN: Four types of ceramic self-ligating brackets were separated into experimental groups (DC, EC, IC, and QK) while a metal self-ligating bracket (EM) was used as the control group. Atomic force microscopy and energy-dispersive x-ray spectroscope were used to examine the surface roughness and chemical composition of each bracket slot and wing. RESULTS: The control group was made of ferrum and chrome while all the experimental groups were comprised of aluminum and oxide. There was a statistically significant difference in the roughness average (Sa) among the various self-ligating brackets (p< 0.001 in slots and p<0.01 in the wing). The slots in the EC group had the lowest Sa, followed by the DC, IC, control, and QK groups. The wings in the IC group had the lowest Sa, followed by the EC, DC, control, and QK groups. CONCLUSIONS: There is a significant difference in the surface roughness of the slots and wings among several types of ceramic self-ligating brackets.


Asunto(s)
Soportes Ortodóncicos , Biopelículas , Cerámica , Aleaciones Dentales , Fricción , Humanos , Ensayo de Materiales , Diseño de Aparato Ortodóncico , Alambres para Ortodoncia , Acero Inoxidable , Propiedades de Superficie
2.
Orthod Fr ; 91(4): 303-321, 2020 Dec 01.
Artículo en Francés | MEDLINE | ID: mdl-33355535

RESUMEN

The aim of this systematic review and meta-analysis was to compare self-ligating brackets (SLBs) considered as a whole to conventional brackets (CBs). An electronic search was performed in three databases (PubMed, MEDLINE via Web of Science, Cochrane Library) from their origin up to June 2017. Additional articles were hand searched from January 2006 to June 2017. This meta-analysis was restricted to randomized controlled trials (RCTs) and split mouth design studies (SMDs). No distinction was made between active and passive SLBs. The following variables were investigated : treatment duration, number of visits, alignment rate, rate of space closure, perception of discomfort during the initial phase of treatment, pain experience during wire insertion or removal, bond failure rate, time to ligate in or to untie an archwire, periodontal indices, occlusal outcomes, transverse arch dimensional changes and root resorption. 25 RCTs and 9 SMDs were finally selected. It was more painful to insert or remove a 0.019× 0.025 SS archwire in/from SLBs. It was significantly quicker to insert or remove an archwire from SLBs. There was less bleeding on probing with SLBs 4 or 5 weeks after bonding. All other variables did not exhibit any significant difference between SLBs and CBs. Out of the 31 comparisons between self-ligating and conventional brackets, 9 only revealed statistically significant differences. This meta-analysis contradicts most of the promotional statements put forward by the distributors.


Asunto(s)
Soportes Ortodóncicos , Resorción Radicular , Cara , Humanos , Boca , Diseño de Aparato Ortodóncico , Alambres para Ortodoncia
3.
Swiss Dent J ; 130(12): 983-993, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33267535

RESUMEN

This analysis was conducted to assess the impact of Coca-Cola on orthodontic materials compared to that of other fluids. Electronical searches were carried out in PubMed, Livivo, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov, supplemented by manual searches in the reference lists of the articles selected for full text evaluation. The risk of bias was assessed on the basis of a "risk of bias summary." A total of 216 bibliographic summaries of articles were obtained, eleven of which were relevant. Nine of these papers showed a low risk, while two publications from one in vivo study exhibited a high risk of bias. The continuing influence of Coca-Cola caused significant discoloration of elastomeric materials and resulted in significantly lower shear bond strength of the brackets and higher corrosion. With regard to orthodontic appliances, additional in situ and in vivo studies are desirable. Special attention should be paid to an appropriate number of samples or patients, as most investigations lacked a sufficient number of test subjects. In addition, investigations with long observation periods and documented beverage consumption should be preferred. The intake of cola-containing beverages during orthodontic therapy and the exposure duration of these beverages to orthodontic material should be reduced to a minimum, as this can impair the adhesive strength and lead to corrosion of orthodontic brackets. The interval between orthodontic appointments should be short to avoid discoloration of orthodontic elastomeric ligatures.


Asunto(s)
Coca , Soportes Ortodóncicos , Bebidas , Cola , Humanos , Soportes Ortodóncicos/efectos adversos
4.
Dental Press J Orthod ; 25(5): 38-43, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33206827

RESUMEN

OBJECTIVE: To evaluate a protocol for bonding metallic brackets after bleaching with hydrogen peroxide (HP). METHODS: 60 extracted maxillary premolar were randomly divided into an unbleached control group and two groups bleached with a solution of 35% hydrogen peroxide prior to bonding. The teeth in one of the treated groups were bonded immediately after bleaching; while the other group was treated with 10% sodium ascorbate immediately after bleaching and before bonding. The teeth in all groups were stored in an artificial saliva solution for 7 days after bonding. The shear bond strength data was measured in megapascals (MPa) and the fail attempts were verified. The significance level was established at p< 0.05. RESULTS: The unbleached group, in which brackets were bonded to untreated enamel, had the highest bond strength values (11.0 ± 5.7MPa) in comparison to the bleached group (7.14 ± 40MPa), in which brackets were bonded to recently bleached enamel. Slightly improved bond strength was observed in the antioxidant group (8.13 ± 5.4MPa), in which the teeth were bleached and then the antioxidant was applied to the teeth before bonding. Unbleached and bleached groups showed statistically significant difference for shear bond strength (p=0.03) and load strength (p=0.03); no significant differences were noted between unbleached and antioxidant groups (p=0.52). CONCLUSION: The antioxidant treatment applied immediately after bleaching was effective in reversing the reduction in shear bond strength of brackets after tooth bleaching.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Blanqueamiento de Dientes , Esmalte Dental , Resistencia al Corte
5.
Braz Dent J ; 31(5): 540-547, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33146339

RESUMEN

The aim of this study was to analyze the influence of orthodontic bracket type (metallic or ceramic) and mouthguard on biomechanical response during impact. Two-dimensional plane-strain models of a patient with increased positive overjet of the maxillary central incisor was created based on a CT scan, simulating the periodontal ligament, bone support, gingival tissue, orthodontic brackets (metallic or ceramic) and mouthguard. A nonlinear dynamic impact finite element analysis was performed in which a steel object hit the model at 1 m/s. Stress distributions (Von Mises and Modified Von Mises) and strain were evaluated. Stress distributions were affected by the bracket presence and type. Models with metallic and ceramic bracket had higher stresses over a larger buccal enamel impact area. Models with ceramic brackets generated higher stresses than the metallic brackets. Mouthguards reduced the stress and strain values regardless of bracket type. Mouthguard shock absorption were 88.37% and 89.27% for the metallic and ceramic bracket, respectively. Orthodontic bracket presence and type influenced the stress and strain generated during an impact. Ceramic brackets generated higher stresses than metallic brackets. Mouthguards substantially reduced impact stress and strain peaks, regardless of bracket type.


Asunto(s)
Protectores Bucales , Soportes Ortodóncicos , Cerámica , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Incisivo , Ensayo de Materiales , Diseño de Aparato Ortodóncico , Estrés Mecánico
6.
Orthod Fr ; 91(3): 249-262, 2020 10 01.
Artículo en Francés | MEDLINE | ID: mdl-33146619

RESUMEN

The use of self-ligating brackets has largely developed in orthodontic practice thanks to numerous advantages, including the reduction of frictional forces during sliding orthodontic mechanic. Faced with scientific evidence, this advantage still seems to be debatable. Our objective was to evaluate in vivo the frictional force of self-ligating brackets by searching for micro-morphological and chemical effects on the active slot surface, after phase of alignment-leveling and after a period in the mouth. 16 brackets from four commercial brands were selected (Damon®, In-Ovation®, Smart-clip® and Carriere®). These brackets were visualized using a scanning electron microscope (SEM) and dispersive energy spectroscopy to study their surface and initial chemical composition. After a period in the mouth, these brackets were debonded and evaluated with SEM, to search topographic and chemical changes in relation to the frictional forces. After a period of three months used for dental alignment, all the brackets show considerable changes in topographic and chemical properties related to frictional forces, with deposit of organic debris whose importance is related to the initial surface different from one manufacturer to another.


Asunto(s)
Soportes Ortodóncicos , Alambres para Ortodoncia , Aleaciones Dentales , Análisis del Estrés Dental , Fricción , Ensayo de Materiales , Diseño de Aparato Ortodóncico , Acero Inoxidable , Propiedades de Superficie
7.
BMC Oral Health ; 20(1): 277, 2020 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-33036600

RESUMEN

BACKGROUND: Conventional brackets are often used during orthodontic therapy of patients with malocclusion. The complex construction of such brackets greatly inhibits oral hygiene, which predisposes to increased carriage of microbiota. Orthodontic brackets could act as reservoir of yeast and predispose to oral candidosis. The aim of this study was to assess Candida prevalence and the role of oral hygiene during fixed appliance therapy. A further aim was to characterize the isolated yeasts according to their ability to form biofilms. METHODS: Seventeen participants (average age 17 ± 7 years) were monitored by taking oral rinses and elastomeric ligature samples, and by evaluating the approximal plaque index (API) and gingival bleeding index (GBI) before and after placement of the orthodontic conventional brackets for 12 weeks. Isolated yeasts were counted and biofilm formation was evaluated. RESULTS: One hundred and sixteen samples (67 oral rinses and 49 orthodontic elastomers) were collected. Ten patients (58.8% subjects) were Candida-carriers (two were colonized after bracket placement) and C. albicans was the most common species. The average number of yeasts in the oral cavity showed some fluctuation during the study, but in general had an upward trend (adj. R2 = 0.7967, p = 0.07025). A correlation was found between median number of yeasts and the periodontal indices (API, GBI). The average API values decreased in the Candida-carriers (adj. R2 = 0.95; p = 0.01709), while average GBI values increased in the noncarriers (adj. R2 = 0.92; p = 0.0256). CONCLUSIONS: Treatment with orthodontic appliances promotes Candida yeast colonization, which is variable over time in terms of strain and species, with dominance of C. albicans, and without increased biofilm-forming activity. The API value decreases over time in carriers, and the GBI value increases in uncolonized patients, which may have predictive significance for the development of oral candidiasis during orthodontic treatment.


Asunto(s)
Higiene Bucal , Soportes Ortodóncicos , Adolescente , Adulto , Candida , Niño , Índice de Placa Dental , Humanos , Soportes Ortodóncicos/efectos adversos , Índice Periodontal , Prevalencia , Adulto Joven
8.
Indian J Dent Res ; 31(4): 585-588, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33107461

RESUMEN

Aim: To evaluate and compare the effect of contamination with haemostatic agents like Tranexamic Acid (TA) and Ethamsylate, on the shear bond strength. Materials and Methods: There are about 100 extracted human premolars randomly segregated into four groups each consisting of 25 samples. Group I was bonded with Transbond, Group II was bonded with Transbond after blood contamination, while groups III and IV were bonded with Transbond after contamination with Tranexamic acid and the shear bond strength was measured. The data were compared by One- way ANOVA and Tukey (HSD) tests. Results: Group I had the highest shear bond strength (SBS) while Group II, where the teeth were contaminated with blood showed the least SBS values ANOVA indicated significant differences between the four groups (P < .05). Tukey HSD revealed that contamination with TA (Group III) had a statistically higher SBS that contamination with Ethamsylate (Group IV) (P < .05). Conclusion: Since tranexamic acid and ethamsylate reduces the bleeding when used during surgery, these haemostatic agents may be considered in bonding situations where blood contamination is anticipated.


Asunto(s)
Recubrimiento Dental Adhesivo , Hemostáticos , Soportes Ortodóncicos , Análisis de Varianza , Humanos , Resistencia al Corte
9.
J Contemp Dent Pract ; 21(6): 621-625, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33025929

RESUMEN

AIM: The present study aimed to assess the efficacy of different dental varnishes in prevention of demineralization of enamel along the orthodontic brackets. MATERIALS AND METHODS: A total of 60 premolars that do not have caries and were extracted for orthodontic purposes were used in this study. Transbond™ Plus was used to bond premolar brackets onto the treated surface of enamel. The teeth were then divided into three groups. Group I: Profluorid varnish, group II: CPP-ACP varnish, and group III: Duraflor™ varnish. A Vickers diamond indenter was used to assess the microhardness of the surface of enamel at baseline, fourth day, and seventh day. RESULTS: A slightly meaner surface microhardness (SMH; 334.20 ± 2.10) was seen in group III when compared with group I (332.16 ± 3.02) and group II (330.40 ± 2.02). The mean SMH was 342.02 ± 0.82 in group I on the fourth day which was slightly higher than that of the baseline values, followed by group III (339.48 ± 0.34) and group II (336.64 ± 1.14). No statistically significant differences were noted between the groups. A higher mean microhardness of 349.84 ± 0.66 was seen in group I on the seventh day, followed by group III (342.26 ± 1.08) and group II (338.18 ± 1.08). A statistically highly significant difference was seen between the groups. CONCLUSION: The present study concluded Profluorid varnish to have maximum potential to reduce demineralization of enamel followed by Duraflor and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) group. CLINICAL SIGNIFICANCE: A most common clinical challenge encountered in orthodontic clinical practice is enamel demineralization or white spot lesion (WSL) development throughout the fixed appliance treatment. Thus, the information about several available varnishes is important to prevent demineralization in regular dental practice.


Asunto(s)
Caries Dental , Soportes Ortodóncicos , Desmineralización Dental , Diente Premolar , Esmalte Dental , Humanos , Soportes Ortodóncicos/efectos adversos
10.
J Contemp Dent Pract ; 21(7): 808-814, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33020368

RESUMEN

AIM: This literature review aims to update the evidence for prevention of white spot lesion (WSL) using orthodontic sealants among patients with fixed orthodontic appliances. BACKGROUND: As a major issue among orthodontists, prolonged treatment duration increases the risk of plaque development around orthodontic brackets and bands. In consequence, this can lead to heightened risk for caries development and higher possibility of WSL development around fixed orthodontic brackets. RESULTS: Increased prevalence of WSLs generally occurs during orthodontic treatment. This review explored various products of orthodontic sealants used to prevent WSL. Orthodontic sealants do not require patient compliance and thus will further lessen the burden among orthodontists as well as support enamel surface for a long period of time during treatment. Certain factors, however, are considered important in the efficacy of these sealants, such as antibacterial activity, color stability, resistance to acid and brush abrasion, and their effect on shear bond strength (SBS). CONCLUSION: The review showed that the use of orthodontic sealants in preventing WSLs during and after fixed orthodontic treatment is significantly effective. However, the bioactive glass is deemed more effective against WSL development due to its ability to immediately repair enamel surface, low cytotoxicity, and high biocompatibility. Moreover, clinical studies on bioactive glass are still needed to determine its acceptability among patients with fixed orthodontic appliance. CLINICAL SIGNIFICANCE: Development of WSL around the orthodontic brackets during treatment is a difficult task among orthodontists. As such, this review explored various strategies to effectively combat WSL development for good oral health and esthetics during orthodontic treatment.


Asunto(s)
Caries Dental/etiología , Caries Dental/prevención & control , Soportes Ortodóncicos/efectos adversos , Ortodoncia , Materiales Dentales , Estética Dental , Humanos
11.
Head Face Med ; 16(1): 20, 2020 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-32891153

RESUMEN

INTRODUCTION: Bond failure during fixed orthodontic treatment is a frequently occurring problem. As bracket rebonding is associated with reduced shear bond strength, the aim of the present investigation is to analyse the effect of different innovative rebonding systems to identify optimised rebonding protocols for orthodontic patient care. METHODS: Metallic brackets were bonded to the frontal enamel surfaces of 240 bovine lower incisors embedded in resin bases. Teeth were randomly divided into two major experimental groups: in group 1 a hydrophilic primer (Assure™ PLUS) was compared to commonly used orthodontic adhesives (Transbond XT™, BrackFix®, Grengloo™) and a zero control. In group 2 different rebonding systems were analysed using a hydrophilic primer (Assure™ PLUS), a methyl methacrylate-consisting primer (Plastic Conditioner) and a conventional adhesive (Transbond XT™). All teeth were tested for shear bond strength according to the DIN-13990 standard, the Adhesive Remnant Index and enamel fracture rate. RESULTS: The hydrophilic primer enhanced shear bond strength at first bonding (Assure™ PLUS 20.29 ± 4.95 MPa vs. Transbond XT™ 18.45 ± 2.57 MPa; BrackFix® 17 ± 5.2 MPa; Grengloo™ 19.08 ± 3.19 MPa; Meron 8.7 ± 3.9 MPa) and second bonding (Assure™ PLUS 16.76 ± 3.71 MPa vs. Transbond XT™ 13.06 ± 3.19 MPa). Using Plastic Conditioner did not seem to improve shear bond strength at rebonding (13.57 ± 2.94). When enamel etching was left out, required shear bond strength could not be achieved (Plastic Conditioner + Assure™ PLUS 8.12 ± 3.34 MPa; Plastic Conditioner: 3.7 ± 1.95 MPa). Hydrophilic priming systems showed decreased ARI-scores (second bonding: 2.63) and increased enamel fracture rates (first bonding: 55%; second bonding 21,05%). CONCLUSIONS: Based on the present study we found that rebonding strength could be compensated by the use of hydrophilic priming systems. The additional use of a methyl methacrylate-consisting primer does not seem to enhance shear bond strength. No etching approaches resulted in non-sufficient bond strength.


Asunto(s)
Grabado Ácido Dental , Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Animales , Bovinos , Cementos Dentales , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte
12.
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
13.
Prog Orthod ; 21(1): 32, 2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32924097

RESUMEN

BACKGROUND: The loss of third-order information in pre-adjusted brackets due to torsional play is a problem in clinical orthodontics. The aim of this study was to evaluate the impact of slot height, archwire height, width and edge bevel's radius on the torsional play for three brackets/archwire systems. METHODS: Ninety brackets with a 0.022 × 0.028 in. slot with McLaughlin-Bennett-Trevisi prescription from three different manufacturers were selected, and the slot's height and depth were measured using a profile projector. Sixty stainless-steel rectangular archwires from three different manufacturers were sectioned and observed with a SEM to measure their height, width, and radius of edge bevel. The recorded data were used to calculate the theoretical torsional play between different slot-archwire combinations. One-way ANOVA was used to compare the measurements within different bracket types and among different manufacturers. RESULTS: Slot height was usually oversized. Archwire's height was usually undersized, but oversized wires were also observed. The radius edge bevel was the most variable parameter. A certain degree of torsional play is always present that differs from one bracket type to another of the same producer and that can even be doubled from one manufacturer to another. CONCLUSIONS: Due to production tolerance, differences between the nominal values and the real dimensions of any components of a slot/archwire system are common. This results in a torsional play that limits torque expression. The archwire's edge bevel plays an important role in torque expression, and clearer information should be provided by the manufacturers regarding this aspect.


Asunto(s)
Soportes Ortodóncicos , Alambres para Ortodoncia , Diseño de Aparato Ortodóncico , Acero Inoxidable , Torque
14.
Dental Press J Orthod ; 25(4): 59-67, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32965388

RESUMEN

OBJECTIVE: To compare the effectiveness of the pretreatment with sandblasting and deproteinization with NaOCl on bond strength (SBS), in situ conversion degree (CD) of brackets in fluorotic enamel, and enamel etching pattern. METHODS: A total of 90 non-carious maxillary premolars were used. The teeth were then assigned to six experimental groups according to: enamel surface (sound and fluorotic enamel); surface treatment (Regular etch with 37% phosphoric acid [RE]; 5.2% sodium hypochlorite + phosphoric acid [NaOCl + RE]; sandblasting + phosphoric acid [sandblasting + RE]). After storage in distilled water (37°C/24h), the specimens were tested at 1 mm/min until failure (SBS). Enamel-resin cement interfaces were evaluated for CD using micro-Raman spectroscopy. The enamel-etching pattern was evaluated under a scanning electron microscope. Data from SBS and in situ CD values were analyzed using ANOVA two-away and Tukey test (α=0.05). The enamel etching pattern was evaluated only qualitatively. RESULTS: For sound enamel, RE showed the highest SBS values, when compared to NaOCl + RE and Sandblasting + RE groups (p< 0.01). Regarding CD, only NaOCl + RE significantly compromised the mean DC, in comparison with other groups (p= 0.002). For fluorotic enamel, the Sandblasting + RE group significantly increased the mean SBS values, in comparison with RE group (p= 0.01) and no significant change was observed for CD (p> 0.52). CONCLUSIONS: The application of NaOCl or sandblasting associated to phosphoric acid improved the SBS of the brackets in fluorotic enamel without compromising the CD of the resin cement, with improving of enamel interprismatic conditioning.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Grabado Ácido Dental , Cementos Dentales , Esmalte Dental , Ensayo de Materiales , Ácidos Fosfóricos , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
17.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(8): 1165-1171, 2020 Aug 30.
Artículo en Chino | MEDLINE | ID: mdl-32895182

RESUMEN

OBJECTIVE: To investigate the effect of orthodontic traction on the microstructure of dental enamel. METHODS: Forty-eight isolated premolars were randomly divided into 6 groups (n=8), including Group A (blank control group), in which the teeth were bonded with the orthodontic brackets without any loading force; Groups B1, B2, and B3 where the teeth were bonded with the orthodontic brackets using clinical adhesives and loaded with 50 g force for 6 months, 200 g force for 6 months, and 200 g force for 1 month, respectively; and Groups C1 and C2, where the teeth were bonded with straight wire brackets using light curing bonding and chemical curing bonding techniques, respectively. All the teeth were embedded with non-decalcified epoxy resin. Scanning electron microscope (SEM), atomic force microscope (AFM), and energy spectrometer (EDS) were used to analyze interface morphology and elemental composition of the teeth sliced with a hard tissue microtome. RESULTS: Compared with those in Group A, the teeth in the other 5 groups showed increased adhesive residue index with microcracks and void structures on the enamel surface under SEM; AFM revealed microcracks on the enamel surface with angles to the grinding direction. A larger loading force on the bracket resulted in more microcracks on the enamel interface. The interface roughness differed significantly between Groups A and C2, and the peak-to-valley distance differed significantly between Groups A, C, and C2. CONCLUSIONS: Orthodontic traction can cause changes in the microstructure of normal dental enamel.


Asunto(s)
Esmalte Dental , Ensayo de Materiales , Soportes Ortodóncicos , Cementos de Resina , Propiedades de Superficie , Tracción
18.
J Orofac Orthop ; 81(6): 396-406, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32875349

RESUMEN

PURPOSE: During bracket bonding, patients often report about thermosensitivity. The reason could be that modern light emitting diode (LED) light curing units run with intensities up to 3200 mW/cm2. In this in vitro pilot study with nonpulpal circulation approaches, the temperatures in the pulpal cavity were measured. METHODS: The study included 60 extracted teeth divided into four equal groups: lower and upper incisors, premolars and molars. Starting at 37 °C (body temperature) as the reference, the temperature increase was measured for the first series on each tooth without a bracket, without and with a recommended hygienic barrier case for the LED light curing unit, and exposition to light once versus twice. The distance between the tooth and light curing unit was 3 mm. In the second test series, a metal bracket was also bonded to each tooth. In the third series, the light exposition distance was increased to 4 mm. RESULTS: In all three test series, significant intrapulpal temperature increase was found: The highest temperatures were recorded after exposure to light once without the hygienic barrier case. In the first test series, this approach showed temperatures even higher than 42.5 °C in the lower incisors (average 42.99 ± 2.23 °C) and premolars (average 42.94 ± 2.15 °C). CONCLUSIONS: Significant increases in the temperature of the pulpal cavity (up to 42.5 °C) may occur during bonding brackets according to the manufacturer's recommendation with an LED light curing unit with in vitro nonpulpal circulation approaches. Therefore it could be reasonable to critically question the recommendation of the manufacturer.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Luces de Curación Dental , Cavidad Pulpar , Humanos , Proyectos Piloto , Temperatura
19.
Sci Rep ; 10(1): 15132, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32934335

RESUMEN

Enamel demineralisation can occur as a side effect during orthodontic treatment with fixed appliances. This study aimed to evaluate the efficacy of the self-assembling peptide P11-4 for remineralisation combined with fluorides, compared to application of fluoride varnish alone. De- and remineralisation was assessed by Quantitative light-induced fluorescence (QLF). Orthodontic brackets were bonded on 108 human enamel samples and white spot lesions were created. The samples were allocated randomly into three groups: Group I received no treatment, group II had a single application of fluoride varnish (22,600 ppm), and group III was treated with P11-4 following a single application of fluoride varnish. Quantitative light-induced fluorescence (QLF) measurements were performed at baseline, after demineralisation and after storage in remineralisation solution for 7 and 30 days. Non-parametric tests (Kruskal-Wallis test and Friedman test) were used for further analysis. After demineralisation, all samples showed a median ΔF -9.38% ± 2.79. After 30 days median ΔF values were as followed: group I = -9.04% ± 2.51, group II = -7.89 ± 2.07, group III = -6.08% ± 2.79). The median ΔF values differed significantly between all groups at all investigation times (p < 0.00001). Application of P11-4 with fluoride varnish was superior to the use of fluorides alone for remineralisation of enamel adjacent to brackets.


Asunto(s)
Cariostáticos/administración & dosificación , Caries Dental/tratamiento farmacológico , Fluoruros Tópicos/administración & dosificación , Soportes Ortodóncicos/efectos adversos , Fragmentos de Péptidos/administración & dosificación , Desmineralización Dental/prevención & control , Remineralización Dental/métodos , Humanos , Desmineralización Dental/etiología
20.
BMC Oral Health ; 20(1): 236, 2020 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-32847568

RESUMEN

BACKGROUND: Orthodontic braces have become symbols of wealth and fashion accessories in some parts of the world. However, there is a scarcity of information about the effects of fashion braces on various aspects of quality of life. Therefore, our aim was to investigate the effects of fashion braces on oral health related quality of life (OHRQoL). METHODS: A cross-sectional study was carried out with data collection from a Google form questionnaire distributed in Saudi Arabia via various forms of social media over a period of 4 months. OHRQoL was assessed using the validated Arabic version of the Oral Health Impact Profile-14 (OHIP-14) questionnaire. The fashion braces group included respondents who had braces installed for fashion purposes only. Therapeutic braces group included subjects who were wearing braces to treat any malocclusion problems. Control group included subjects who did not have any kind of braces. People who had previously completed orthodontic treatments were excluded from the study. The negative impacts were divided into seven domains and a total OHIP score was calculated. Statistical analyses and data illustration were performed with SPSS v25 (IBM, NY). RESULTS: A total of 1141 people voluntarily participated in the study. More than 60% of the participants were in the control group while 33.7% had conventional braces for therapeutic reasons and 3.4% had fashion braces. Sociodemographic distributions varied among the groups, with the majority of the fashion braces group having education below the university level and family incomes less than average. There were significant group differences in OHIP domains. Physical pain was the most frequently reported complaint by all subjects and was the highest in the therapeutic braces group. People with therapeutic braces reported significantly higher functional limitation and physical disability than the controls. Fashion braces group reported significantly lower psychological discomfort and disability, social disability and handicap compared to control groups. CONCLUSIONS: The illustrated effects of fashion braces on OHRQoL suggest the need to study the role of social media and educate the public on the use of braces to minimize the negative effects experienced by individuals.


Asunto(s)
Soportes Ortodóncicos , Calidad de Vida , Estudios Transversales , Humanos , Internet , Salud Bucal , Arabia Saudita , Encuestas y Cuestionarios
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