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1.
Clin Oral Investig ; 28(10): 525, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269644

RESUMEN

OBJECTIVE: To evaluate the effect of rapid palatal expansion (RPE) using Haas-type expanders on children's oral health-related quality of life (OHRQOL) and compare said effect with that previously reported for the use of Hyrax-type expanders. MATERIALS AND METHODS: Forty participants aged 8-10 years with transverse maxillary deficiency were treated using Haas appliances. OHRQOL was measured using the CPQ8 - 10 before RPE, during RPE (T1), at the end of RPE (T2), and 1 month after appliance removal (T3). Generalized mixed models were fitted to assess the effect of the Haas-type expander compared to previously collected data (a nontreated and a Hyrax-type expander-treated group). RESULTS: RPE with Haas-type appliances had a negative impact on overall OHRQOL at T1 and T2 (P = 0.001), and a positive impact at T3 (P = 0.001). The Haas-type expander had a significantly greater negative impact on OHRQOL than the Hyrax-type appliance during RPE. At T1, overall scores using the Haas-type expander were 1.08 times the scores using the Hyrax-type expander (i.e., 8% increase; 95% CI, 1.01-1.17; P = 0.033). Patients using the Haas appliance had 1.24 times the scores of those using Hyrax-type devices for the oral symptoms domain at T1 (i.e., 24% increase; 95% CI, 1.06-1.46; P = 0.009). CONCLUSIONS: Correction of the transverse maxillary deficiency by RPE using the Haas appliance in children 8-10 years improves OHRQOL. The Haas- and Hyrax-type devices temporarily worsen OHRQOL during treatment, however, the negative impact is less with the Hyrax-type expander than with the Haas-type expander, because it causes fewer negative oral symptoms. CLINICAL RELEVANCE: From a patient-centered perspective, the use of the Hyrax over the Haas appliance may be suggested as it causes less negative oral symptoms during use.


Asunto(s)
Técnica de Expansión Palatina , Calidad de Vida , Humanos , Técnica de Expansión Palatina/instrumentación , Niño , Femenino , Masculino , Resultado del Tratamiento , Salud Bucal , Diseño de Aparato Ortodóncico , Encuestas y Cuestionarios , Maxilar/anomalías
2.
J Adhes Dent ; 16(1): 15-20, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23678480

RESUMEN

PURPOSE: To evaluate the relationship between biocompatibility and degree of monomer conversion of composites used to bond brackets to enamel, porcelain, resin, or metal surfaces at different time intervals. MATERIALS AND METHODS: Twenty-four male Wistar rats were used, divided into 4 groups (n = 6) as follows: group C (control, polyethylene), group TCC (Transbond Color Change), group QC (Quick-Cure), and group EB (Eagle Bond). These substances were inserted into subcutaneous tissue. The events of inflammatory infiltrate, edema, necrosis, granulation tissue, multinuclear giant cells, young fibroblasts, and collagen formation were analyzed. The degree of conversion was evaluated by the Fourier method using infrared spectroscopy. Biocompatibility and degree of conversion were statistically analyzed using the Kruskal-Wallis and Dunn tests, and ANOVA and Tukey's test, respectively (p < 0.05). RESULTS: The composites caused a small amount of inflammatory infiltrate, edema, and granulation tissue at all experimental time intervals, showing a gradual reduction over time (p > 0.05). Group TCC showed the highest amount of fibroblasts and EB the smallest at the time interval of 15 days (p = 0.035). Group TCC showed the highest amount of collagen fibers and EB the smallest throughout the experiment; there was a significant difference in terms of collagen fibers between groups QC and EB, which differed from the control at 7 days (p = 0.006), and between groups EB and TCC (p = 0.018) at 30 days. Monomer conversion ranged from 64.1% in group EB at 7 days to 85.3% in group TCC at 30 days. CONCLUSION: Transbond Color Change composite showed a higher degree of conversion and a better healing process compared to Eagle Bond composite at 15 and 30 days. Quick-cure composite demonstrated a better degree of conversion and healing process than that of Eagle Bond, but this was not statistically significantly different.


Asunto(s)
Materiales Biocompatibles/química , Resinas Compuestas/química , Cementos de Resina/química , Animales , Bisfenol A Glicidil Metacrilato , Celulitis (Flemón)/patología , Colágeno/análisis , Edema/patología , Fibroblastos/patología , Análisis de Fourier , Células Gigantes/patología , Tejido de Granulación/patología , Masculino , Ensayo de Materiales , Metacrilatos/química , Necrosis , Polietileno/química , Polietilenglicoles/química , Polimerizacion , Ácidos Polimetacrílicos/química , Ratas , Ratas Wistar , Espectrofotometría Infrarroja , Tejido Subcutáneo/patología , Factores de Tiempo
3.
Am J Dent ; 27(5): 227-32, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25842453

RESUMEN

PURPOSE: To evaluate the effect of storage in S. mutans culture or water on the durability of fluoride and MDPB-containing adhesive system on artificial caries-affected primary dentin. METHODS: Dentin flat surfaces of primary molars were submitted to artificial caries development using S. mutans biofilm. CAPD cavities were restored with Adper Scotchbond Multi-Purpose (SBM) or Clearfil Protect Bond (CPB) and they were serially sectioned into sticks (1 mm2 cross-sectional area) and stored in S. mutans biofilm for 3 days, in deionized water for 3 months and afterwards subjected to microtensile bond strength (µTBS) test. A control group was submitted to immediate TBS testing. Two-way ANOVA and Tukey's tests were used. Failure sites were observed by SEM and classified as cohesive (dentin or resin) and adhesive failures. RESULTS: The control group showed the highest µTBS values (MPa) for both SBM (25.2 ± 8.5) and CPB (15.6 ± 6.1) adhesive systems. A significant decrease in µTBS values after S. mutans biofilm and water storage was observed for SBM (18.7 ± 5.7 and 17.4 ± 4.1, respectively) and CPB (13.9 ± 5.2 and 13.7 ± 4.8, respectively), but no difference was found between them. The highest percentage of adhesive failure was observed for all groups. However, cohesive failure in dentin was observed in a higher percentage for SBM than CP.


Asunto(s)
Biopelículas , Caries Dental/metabolismo , Dentina/metabolismo , Fluoruros/administración & dosificación , Compuestos de Piridinio/administración & dosificación , Streptococcus mutans/metabolismo , Humanos , Técnicas In Vitro , Microscopía Electrónica de Rastreo
4.
J Dent ; 149: 105316, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39159744

RESUMEN

OBJECTIVES: This study assessed the effect of NaF/Chit suspensions on enamel and on S. mutans biofilm, simulating application of a mouthrinse. METHODS: The NaF/Chit particle suspensions were prepared at molar ratio [NaF]/Chitmon]≈0.68 at nominal concentrations of 0.2 % and 0.05 % NaF and characterized by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering and zeta potential. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured. The S. mutans biofilm was formed for 7 days on eighty human enamel blocks that were divided into eight groups (n = 10/group): i) 0.05 % NaF solution; ii) 0.31 % Chit solution; iii) NaF/Chit(R=0.68) suspension at 0.05 % NaF; iv) 1.0 % HAc solution (Control); v) 0.2 % NaF solution; vi) 1.25 % Chit solution; vii) NaF/Chit(R=0.68) suspension at 0.2 % NaF; viii) 0.12 % chlorhexidine digluconate. The substances were applied daily for 90 s. S. mutans cell counts (CFU/mL) were performed, and the Knoop microhardness (KHN) of enamel samples were measured before and after biofilm formation. The KHN and CFU/mL data were analyzed by repeated measure ANOVA and Tukey's test (α = 0.05). RESULTS: Interactions between NaF and Chit were evidenced in solid state by FTIR spectra. The NaF/Chit complexes showed spontaneous microparticle formation and colloidal stability. The MIC and MBC ranged from 0.65 to 1.31 mg/mL. The NaF/Chit(R=0.68) suspension at 0.2 %NaF Group showed lower CFU/mL values than other groups. The NaF/Chit(R=0.68) suspensions Groups had the highest KHN values after biofilm formation. CONCLUSIONS: The NaF/Chit(R=0.68) complexes exhibited an antibacterial effect against S. mutans biofilm and reduced the enamel hardness loss. CLINICAL SIGNIFICANCE: The NaF/Chit(R=0.68) suspensions showed potential to be used as a mouthrinse for caries prevention.


Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Esmalte Dental , Pruebas de Sensibilidad Microbiana , Fluoruro de Sodio , Streptococcus mutans , Biopelículas/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Esmalte Dental/efectos de los fármacos , Esmalte Dental/microbiología , Humanos , Antibacterianos/farmacología , Fluoruro de Sodio/farmacología , Quitosano/farmacología , Quitosano/química , Espectroscopía Infrarroja por Transformada de Fourier , Antisépticos Bucales/farmacología , Antisépticos Bucales/química , Coloides , Cariostáticos/farmacología , Cariostáticos/química
5.
Am J Orthod Dentofacial Orthop ; 143(4 Suppl): S72-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23540639

RESUMEN

INTRODUCTION: Self-ligating orthodontic brackets rely on clips, rather than ligatures, to hold the archwire in place. It is unknown whether replacing ligatures with clips affects the adherence of Streptococcus mutans. The aim of this research was to evaluate whether self-ligating brackets have an advantage over conventional brackets as determined by the adherence of S mutans. METHODS: The sample consisted of 50 esthetic brackets, divided into 3 experimental groups and 2 control groups of 10 brackets each. Two experimental groups were active self-ligating brackets (QuicKlear; Forestadent, Pforzheim, Germany; and In-Ovation C; Dentsply GAC, Bohemia, NY); the other was a passive self-ligating bracket (Damon 3; Ormco, Glendora, Calif). The 2 control groups were conventional brackets (Mystique; Dentsply GAC; and Clarity; 3M Unitek, Monrovia, Calif). The brackets were randomly bonded to the canines, first and second premolars, and first and second molars in the mandibular left hemiarch of 10 male participants. Biofilm was collected from the tooth surfaces before bonding and from the brackets on day 21 and placed in Petri dishes containing Mitis salivarius agar. The brackets were removed on day 28 and examined by using scanning electron microscopy. Statistical analysis, analysis of variance, and the Tukey correction with a P value of 0.05 were used. RESULTS: The greatest numbers of colonies were found in an active self-ligating bracket group (In-Ovation C), and the fewest colonies were in a conventional bracket group (Clarity). The largest colonies formed on active self-ligating brackets. In the slot, the greatest formation was in a control group (Mystique). CONCLUSIONS: Self-ligating esthetic brackets do not promote greater or lesser S mutans colonization when compared with conventional brackets. Differences were found to be related to the material composition of the bracket.


Asunto(s)
Diseño de Aparato Ortodóncico , Soportes Ortodóncicos/microbiología , Streptococcus mutans/fisiología , Adulto , Análisis de Varianza , Adhesión Bacteriana , Recuento de Colonia Microbiana , Estética Dental , Humanos , Masculino
6.
Aust Orthod J ; 29(2): 139-44, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24380132

RESUMEN

INTRODUCTION: Sterilisation using peracetic acid (PAA) has been advocated for orthodontic elastic bands. However, cane-loaded elastomeric ligatures can also become contaminated during processing, packaging, and manipulation before placement in the oral cavity and are therefore susceptible, and possible causes, of cross-contamination. AIM: To test the hypothesis that 0.25% peracetic acid (PAA), following the sterilisation of elastomers, influences the cytotoxicity of elastomeric ligatures on L929 cell lines. MATERIALS AND METHODS: Four hundred and eighty silver elastomeric ligatures were divided into 4 groups of 120 ligatures to produce, Group TP (latex natural, bulk pack, TP Orthodontics), Group M1 (Polyurethane, bulk pack, Morelli), Group M2 (Polyurethane, cane-loaded, Morelli) and Group U (Polyurethane, cane-loaded, Uniden). Of the 120 ligatures in each group, 100 were sterilised in 0.25% PAA at time intervals (N = 20) of 1 hour, 2 hours, 3 hours, 4 hours and 5 hours. The 20 remaining elastomeric ligatures in each group were not sterilised and served as controls. Cytotoxicity was assessed using L929 cell lines and a dye-uptake method. Analysis of variance (ANOVA), followed by the Tukey post hoc test (p < 0.05) determined statistical relevance. RESULTS: There was a significant difference between TP, Morelli and Uniden elastomerics (p < 0.05), but no difference between the two types of Morelli elastomerics at the 1 hour time interval. In addition, there was a significant difference between Group CC and the other groups assessed, except between Groups CC and TP at the 1 hour time interval. The non-sterilised elastomeric ligatures showed similar cell viability to that observed after 1 hour of standard sterilisation. CONCLUSION: PAA did not significantly influence the cytotoxicity of elastomeric ligatures after a sterilisation time of 1 hour and is therefore recommended for clinical use.


Asunto(s)
Desinfectantes Dentales/uso terapéutico , Elastómeros/toxicidad , Aparatos Ortodóncicos , Ácido Peracético/uso terapéutico , Esterilización/métodos , Animales , Técnicas de Cultivo de Célula , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colorantes , Desinfectantes Dentales/química , Elastómeros/química , Fibroblastos/efectos de los fármacos , Látex/química , Látex/toxicidad , Ensayo de Materiales , Rojo Neutro , Ácido Peracético/química , Poliuretanos/química , Poliuretanos/toxicidad , Ratas , Factores de Tiempo
7.
J Mech Behav Biomed Mater ; 147: 106134, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37742597

RESUMEN

Fluoridated mouthrinse is indicated for individuals with high risk of caries. Chitosan (Chit) exhibits antibacterial properties, but little is known about its effects on enamel when combined with sodium fluoride (NaF) to form NaF/Chit supramolecular complexes. In our study, NaF/Chit supramolecular complexes structured as microparticles were synthetized and characterized, and their effects on human enamel were evaluated after cariogenic challenge simulating the daily mouthrinse use. Initially, NaF/Chit complex formation was investigated based on several titrations by measuring the zeta potential, electrical conductivity (κ), hydrodynamic diameter (Dh), viscosity (η) and heat flow (by isothermal titration calorimetry) against the molar ratio [NaF]/[Chitmonomer], which allowed us to identify the interactions between Chit-NaF with a stoichiometry of approximately 0.68. Spontaneous microparticle formation was observed. Samples of enamel blocks were prepared and divided into eight groups (n = 10/group): (i) 0.2% Chit; (ii) 0.2% NaF; (iii) 0.2% NaF/Chit suspension; (iv) 0.2% acetic acid; (v) 0.05% Chit; (vi) 0.05% NaF; (vii) 0.05% NaF/Chit suspension; and (viii) 0.05% acetic acid. Cariogenic challenge was performed in each sample by cycling in demineralization and remineralization solutions for 7 days. Before each demineralization cycle, the corresponding substances were passively applied daily for 90 s, even in groups with 0.02% concentration. After 7 days, samples were examined for Knoop hardness (KHN) measurements. The data were analyzed by repeated-measures ANOVA and Tukey tests (α = 0.05). The 0.2% NaF and 0.2% NaF/Chit groups showed higher KHNpost-challenge values than the other groups. The 0.2% NaF/Chit microparticle suspension reduced the enamel hardness loss after cariogenic challenge as effectively as the 0.2% NaF solution and demonstrated potential for use in a formulation with anti-caries effects.

8.
Front Oral Health ; 3: 887765, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35711624

RESUMEN

The COVID-19 pandemic has brought health damage and socioeconomic disruptions, together with lifestyle disorders around the world. Children are one of the most commonly affected, mainly due to social isolation and changes in eating habits and physical activities. This way, the risk of weight gain and obesity is possibly enhanced, as well as poor oral hygiene conditions and early childhood caries (ECC) development during the lockdown. In children under 6 years of age, ECC is defined as carious lesions in one or more primary teeth, with or without cavitation. Importantly, alterations in the oral microbiome caused by changes in children lifestyles have much more than a local impact on oral tissues, interplaying with the gut microbiome and influencing systemic environments. Recent studies have been exploring the oral health conditions, eating habits, and weight gain in the childhood population during the COVID-19 pandemic; however, there is a lack of information concerning the association among oral and gut microbiome, dental caries, and obesity in the COVID-19 era. In this context, this review aimed at analyzing a possible relationship between the oral and gut microbiome, caries, and obesity in children during the COVID-19 pandemic.

10.
Am J Orthod Dentofacial Orthop ; 140(5): 732-3, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22051494

RESUMEN

The aim of this article was to relate the clinical case of an HIV-positive orthodontic patient who reported that her cheeks had been hurting since treatment began. We started with the data collected in anamnesis and by contact with the patient's physician, and a diagnosis of facial lipodystrophy as a result of the use of retroviral drugs was reached. The patient was referred to a dermatologist for treatment of the facial lipodystrophy.


Asunto(s)
Mejilla/patología , Cara , Síndrome de Lipodistrofia Asociada a VIH/diagnóstico , Ortodoncia Correctiva , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Adulto , Antirretrovirales/efectos adversos , Antirretrovirales/uso terapéutico , Femenino , Humanos
11.
Am J Orthod Dentofacial Orthop ; 140(4): 562-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21967945

RESUMEN

This article describes the orthodontic treatment of a patient with Lowe syndrome. The objective of the treatment was to improve the patient's dental relationships and consequently his quality of life. This was achieved by maxillary expansion and extraction of the mandibular central incisors and maxillary deciduous canines. The teeth were aligned and leveled with a fixed orthodontic appliance. Satisfactory results were obtained at the end of treatment, with substantial improvement in dental esthetics, occlusal function, and facial profile.


Asunto(s)
Maloclusión/terapia , Síndrome Oculocerebrorrenal/complicaciones , Ortodoncia Correctiva , Adolescente , Cefalometría/métodos , Estética Dental , Humanos , Masculino , Maloclusión Clase II de Angle/terapia , Síndrome Oculocerebrorrenal/psicología , Técnica de Expansión Palatina , Calidad de Vida , Retrognatismo/terapia , Extracción Seriada , Técnicas de Movimiento Dental , Resultado del Tratamiento
12.
Eur J Orthod ; 32(5): 567-70, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20164128

RESUMEN

The purpose of this study was to compare the bond strengths and to evaluate the debonding site using the adhesive remnant index (ARI) provided by a conventional acid-etch conditioner and a new self-etching adhesive system, Xeno IV (Dentsply Caulk). One hundred and eighty bovine lower incisors were randomly divided into six groups (n = 30). In groups 1, 2, and 3, Transbond XT (3M Unitek) composite was used to bond the brackets to enamel samples conditioned with 37 per cent phosphoric acid + XT primer (3M Unitek), Xeno IV + XT primer, or Xeno IV only, respectively. In groups 4, 5, and 6, the bonding procedures were performed using Fuji Ortho LC (GC Corp.) resin-modified glass ionomer cement unconditioned, enamel conditioned with 37 per cent phosphoric acid, or Xeno IV, respectively. All samples underwent thermocycling and then shear bond strength (SBS) testing was performed using a universal testing machine (Emic DL 10.000). Analysis of variance was applied. For the post hoc test, the Tukey's test was used. Kruskal-Wallis and Mann-Whitney U-tests were used to assess ARI scores. The results demonstrated no statistical differences between groups 1, 2, and 3. However, statistically significant differences were found between these samples and groups 4, 5, and 6. With regard to ARI score, the highest mean value was found in group 5 (Fuji Ortho LC + 37 per cent acid conditioning), whereas group 4 (Fuji Ortho LC + no conditioning) had the lowest SBS. Xeno IV self-etching bonding agent was able to bond orthodontic brackets in association with Transbond XT composite as well as with Fuji Ortho LC, thus maximizing bracket bonding.


Asunto(s)
Grabado Ácido Dental/métodos , Resinas Acrílicas/química , Recubrimiento Dental Adhesivo/métodos , Desconsolidación Dental , Soportes Ortodóncicos , Cementos de Resina/química , Silicatos de Aluminio/química , Animales , Bovinos , Esmalte Dental/efectos de los fármacos , Análisis del Estrés Dental , Ensayo de Materiales , Cementos de Resina/clasificación
13.
J Orthod ; 37(2): 118-20, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20567035

RESUMEN

Mini-screws are small enough to be inserted into narrow spaces that could not be used for endosseous implants, such as the alveolar bone between the roots of adjacent teeth. Mini-screw placement into these sites can be challenging because of the risk of root damage. The present article describes, step by step, how to manufacture an adjustable surgical guide to facilitate the placement of orthodontic mini-screws, thus reducing the risk of injury to roots and important anatomical structures.


Asunto(s)
Tornillos Óseos , Implantación Dental Endoósea/instrumentación , Métodos de Anclaje en Ortodoncia/instrumentación , Alambres para Ortodoncia , Soldadura Dental , Humanos , Miniaturización , Tecnología Odontológica/instrumentación
14.
Aust Orthod J ; 26(1): 73-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20575204

RESUMEN

BACKGROUND: Ozone water can be used to eliminate micro-organisms from the water systems in dental offices. OBJECTIVES: To determine if ozone water diminishes the bond strength of orthodontic adhesives. METHODS: One hundred and twenty bovine mandibular incisors were randomly divided into four equal groups. The teeth were cleaned with pumice and washed either with tap water (Groups 1 and 3) or with ozone water Groups (2 and 4) before bonding stainless steel orthodontics brackets to the teeth with either a composite resin (Groups 1 and 2; Transbond XT, 3M Unitek, Monrovia, CA, USA) or a resin-modified glass ionomer cement (Groups 3 and 4; Fuji Ortho LC, GC America Corporation, Tokyo, Japan). The manufacturers' recommendations for bonding were followed. All samples were subjected to thermal cycling and the shear bond strengths were determined with a universal testing machine. The Adhesive Remnant Index (ARI) was used to score the amount of resin remaining on the teeth after debonding the brackets. RESULTS: There were no statistical differences in the shear bond strengths of the brackets debonded from enamel washed with either ozone water or tap water or between the groups bonded with the two adhesive resins (p = 0.595). The ARIs in Groups 2 and 3 were significantly different from the ARIs in Groups 3 and 4 (p = 0.030). CONCLUSION: Ozone water did not alter the bond strength of brackets bonded with composite resins, but it did alter the sites of resin fracture when Fuji Ortho LC was used.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales/química , Desinfectantes Dentales/química , Soportes Ortodóncicos , Oxidantes Fotoquímicos/química , Ozono/química , Agua/química , Resinas Acrílicas/química , Silicatos de Aluminio/química , Animales , Bovinos , Resinas Compuestas/química , Aleaciones Dentales/química , Esmalte Dental/ultraestructura , Análisis del Estrés Dental/instrumentación , Cementos de Ionómero Vítreo/química , Ensayo de Materiales , Distribución Aleatoria , Cementos de Resina/química , Resistencia al Corte , Acero Inoxidable/química , Estrés Mecánico , Propiedades de Superficie , Temperatura
15.
Aust Orthod J ; 26(1): 16-20, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20575194

RESUMEN

BACKGROUND: Separating elastics may be cytotoxic to the interdental gingival tissues. Both latex and non-latex separating elastics are widely used and both types should be biocompatible. OBJECTIVE: To determine if latex and non-latex orthodontic separating elastics are cytotoxic. METHODS: The cytotoxicity of natural latex (Groups A, D and O) and non-latex (Group M) orthodontic separating elastics were determined by incubating 15 elastics of each type in Eagle's essential medium (MEM), removing the supernatant after 24, 48, 72 and 168 hours and adding it to cultures of L-929 mouse fibroblasts in growth medium (MEM plus glutamine, garamicine, fungizone, sodium bicarbonate, buffered saline and foetal calf serum). To verify the cell response in extreme situations, three additional groups were included: Group CC (cell control), consisting of L-929 cells not exposed to supernatants from the maintenance medium with the elastics; Group C+ (positive control), consisting of Tween 80; Group C- (negative control), consisting of phosphate buffered saline solution. The positive and negative controls were incubated in MEM maintenance medium for 24, 48, 72 and 168 hours and the extracted elutes were added to L-929 line cells incubated in the growth medium. The viability of the cells was determined with neutral red (dye-uptake method) at 24, 48, 72 and 168 hours. The data were analysed with the analysis of variance (ANOVA) and Tukey's multiple comparison test. The significance level was p < or = 0.05. RESULTS: The elastics in Groups A, D and O induced greater cell lysis at 72 hours compared to the other experimental times. There were statistically significant differences between the cytotoxicity of the elastics in Groups A, D and O in relation to Group CC for experimental times of 24, 48, 72 and 168 hours (p > 0.05). There was not, however, a statistically significant difference between Groups D and CC at 24 hours. CONCLUSION: The latex and non-latex orthodontic separating elastics tested were considered to be biocompatible.


Asunto(s)
Materiales Dentales/toxicidad , Elastómeros/toxicidad , Aparatos Ortodóncicos , Animales , Muerte Celular , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colorantes , Medios de Cultivo Condicionados , Fibroblastos/efectos de los fármacos , Látex/toxicidad , Ensayo de Materiales , Ratones , Rojo Neutro , Elastómeros de Silicona/toxicidad , Factores de Tiempo
16.
Mater Sci Eng C Mater Biol Appl ; 104: 109885, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31500048

RESUMEN

In the present study chitosan (Chit) nanoparticles were synthetized by the ionic gelation process, using tripolyphosphate (TPP) as crosslinking agent. The TPP/Chit nanoparticle formation was evaluated by titrations, measuring electrical conductivity (k), zeta potential (ZP), hydrodynamic diameter (Dh), viscosity (η) and heat by isothermal calorimetry (ITC). The antifungal effects were evaluated by C. albicans time-kill assays, inhibition of C. albicans initial adhesion and biofilm formation in comparison with nystatin and chitosan. Conductometric titration exhibited a typical precipitation profile, with an inflection at molar ratio of [TPP]/[Chitmon] ≈ 0.3, suggesting a 1:3.3 stoichiometry. The highest Dh, ZP and η values were shown at the beginning of titrations, due to the intramolecular repulsion between Chit-Chit. With addition of TPP, the values showed gradual reduction, with an intermediary transition at [TPP]/[Chitmon] ≈ 0.16, which was attributed to the partial breakdown of interchain crosslinking and formation of discrete charged aggregates. After this point, reaction should occur by neutralization of these assemblies, causing new reduction in values of Dh, ZP and η until [TPP]/[Chitmon] ≈ 0.3, when they reached their lowest values. ITC experiment also showed the occurrence of two bindings (K1 = 3.6 × 103 and K2 = 7.7 × 104), which were entropy driven. Biological results showed lower C. albicans viability for TPP/Chit over 24 h compared with chitosan and nystatin at MIC and 2 MIC. Moreover, TPP/Chit showed 25-50% inhibition of C. albicans adhesion and biofilm formation. The results showed that TPP/Chit nanoparticles reduced the initial adhesion and biofilm formation of C. albicans and demonstrated potential for use in a formulation for the treatment of oral candidiasis.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Quitosano/análogos & derivados , Quitosano/química , Coloides/química , Nanopartículas/química , Geles/química , Nistatina/química , Polifosfatos/química
17.
Angle Orthod ; 76(4): 700-4, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16808580

RESUMEN

OBJECTIVE: To assess the shear bond strength of metallic orthodontic brackets bonded with either Fuji Ortho or Ortho Glass LC resin-reinforced glass ionomer cements to enamel surfaces under different conditions, namely, enamel without etching, enamel conditioned with 37% phosphoric acid and enamel conditioned with Transbond Plus Self Etching Primer (TPSEP). MATERIALS AND METHODS: One hundred and five bovine inferior incisors were divided into seven groups (n = 15). In group 1 (control) Transbond XT was used according to the manufacturer's recommendations. In groups 2, 3, and 4 all using Fuji Ortho LC, the brackets were bonded, respectively, to enamel nonetched, enamel etched with 37% phosphoric acid, and enamel etched with TPSEP. In groups 5, 6, and 7, the bonding was performed using Ortho Glass LC under the same enamel conditions observed in the other experimental groups. After 24 hours, shear bond strength tests were performed for all samples at a crosshead speed of 0.5 mm/min. RESULTS: The results (MPa) showed no statistically significant difference between groups 1, 3, and 4 (P > .05). However, such groups were statistically superior to the others (P < .05). No statistically significant difference was observed between groups 2, 6, and 7 (P > .05). Group 5 showed the lowest shear strength value, which was also statistically inferior to the other groups (P < .05). CONCLUSIONS: Regardless of the enamel treatment, Fuji Ortho LC yielded shear strength values superior to those from Ortho Glass LC.


Asunto(s)
Aleaciones Dentales/química , Recubrimiento Dental Adhesivo , Esmalte Dental/ultraestructura , Cementos de Ionómero Vítreo/química , Soportes Ortodóncicos , Cementos de Resina/química , Grabado Ácido Dental , Resinas Acrílicas/química , Silicatos de Aluminio/química , Animales , Bovinos , Ensayo de Materiales , Ácidos Fosfóricos/química , Distribución Aleatoria , Resistencia al Corte , Propiedades de Superficie , Factores de Tiempo
18.
Angle Orthod ; 86(4): 638-43, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26367312

RESUMEN

OBJECTIVE: To evaluate the extent to which different types of malocclusion influence the development of affective/romantic relationships among young adults of both sexes. MATERIALS AND METHODS: A cross-sectional study was conducted with 360 men and women ranging in age from 18 years to 25 years. Criteria for exclusion from the sample were the following: participants could not be married, visually impaired, or students of a higher education course in the area of health. In this study, images of young adult men and women in the same age range as that of the evaluators were used. These images were manipulated to create different types of malocclusion: diastema, open bite, crowding, gingival (or gummy) smile, little exposure of teeth. Six groups of images containing six images each were formed and consisted of two experimental images (digitally manipulated) and four control images. These images were provided to the participants, who evaluated them by means of a questionnaire and a visual analog scale. The Kruskal-Wallis, Mann-Whitney, chi-square, and Fisher exact tests were used for data analysis. RESULTS: All malocclusions had a negative impact on acceptance by the evaluators for the purposes of affective/romantic relationships, with crowding being the type of malocclusion that led to the highest level of rejection (P < .01). CONCLUSION: Malocclusions have a negative influence on the development of affective/romantic relationships among young adults. Individuals with good occlusion are seen in a more positive light, from the perspective of affective life.


Asunto(s)
Estética Dental , Relaciones Interpersonales , Maloclusión , Adolescente , Adulto , Estudios Transversales , Diastema , Femenino , Humanos , Masculino , Sonrisa , Adulto Joven
19.
J Dent ; 43(3): 297-308, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25572792

RESUMEN

OBJECTIVES: The use of fixed orthodontic appliances makes it difficult to clean the teeth and accessories associated with it. For this reason, orthodontic patients have used oral antiseptics as coadjuvent means to reduce cariogenic plaque. The aim of this systematic review was to evaluate the effectiveness of oral antiseptics on the reduction of cariogenic plaque on orthodontic patients. DATA: This review has been registered at PROSPERO--international prospective register of systematic reviews under the number CRD42013006857. SOURCES: A systematic review of the literature was conducted in the following electronic databases: Scopus, PubMed, Web of Science, Medline, Embase and Cochrane, Grey literature and Clinical Trials, without limitations on the year of publication or language. Clinical studies in patients with fixed orthodontic appliances, who were making use of oral mouthwashes in order to reduce cariogenic plaque, were included. Articles with patients using systemic drugs, syndromic patients, those using mouthwashes for other purposes and/or using different cleaning techniques, and clinical cases were excluded. After selection by title and abstract, potentially eligible articles were read in full. The methodological quality and risk of biases of articles included were evaluated according to the characteristics of the study, measurements and statistical analyses of the study. The methodological quality was classified as high, moderate or low. STUDY SELECTION: The search identified 2716 articles, of which 15 met the inclusion criteria. Of these, 8 analyzed chlorhexidine-based mouthwashes, while in 1 article Cetylpyridinium was used; 1 analyzed the mouthwash containing sanguinaria; 1 the use of NaF; 2 articles the use of AmF/SnF2; 2 the use of Listerine(®), 1 also analyzed the association between mouthwashes with octenidine and with PVP-I. Of the articles analyzed, 11 were classified as having high and 4 as having moderate methodological quality. CONCLUSION: There is evidence of effectiveness of the use of oral mouthwashes in the control of cariogenic plaque in patients with fixed orthodontic appliances. The orthodontists may suggest the use of oral antiseptics in the oral hygiene of their patients as coadjuvent means to reduce cariogenic plaque. CLINICAL SIGNIFICANCE: Given current evidence, orthodontists may prescribe mouthwash as an auxiliary method in the control of cariogenic biofilm in orthodontic patients.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Biopelículas/efectos de los fármacos , Antisépticos Bucales/uso terapéutico , Aparatos Ortodóncicos , Placa Dental/tratamiento farmacológico , Humanos , Higiene Bucal
20.
Braz Dent J ; 25(2): 170-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25140724

RESUMEN

The aim of this study was to evaluate the post-treatment anteroposterior and vertical alterations in skeletal Class II malocclusion with different maxillary patterns in patients treated with modified Thurow appliance. Forty-five patients (22 girls and 23 boys) with skeletal Class II and angle SN.GoGn ≤ 35 and different maxillary patterns (n = 15), as follows: retrusive (SNA<80°), normal (SNA = 80°- 84°) or protrusive (SNA>84°) maxilla; mean age 9 years at pre-treatment (T1) and 9 years and 10 months at post-treatment (T2), were treated with modified Thurow cervical traction appliance, with expander screw and extraoral face bow with 10° to 20° fold in relation to the intraoral arch. Force of 500 gf was applied and use for 12 to 14 h/day, with fortnightly adjustments. Analysis of variance ANOVA followed by post-hoc Tukey and Kruskal-Wallis test, followed by Mann-Whitney were used (α = 5%). In changes obtained from stage T1 to T2, no statistically significant differences were found among the groups Protrusive, normal and retrusive maxilla for the variables SNB, SN.GoGn, 1.NA, overjet, overbite and Class II discrepancy (right and left) (p>0.05). Angular measurements SNA and ANB in the protrusive maxilla group were significantly greater than in the normal and retrusive maxilla groups (p<0.01). However, in the normal maxilla group these values did not differ significantly from those of the retrusive maxilla group (p>0.05). Within the limits of this study, it may be concluded that the modified Thurow cervical traction appliance was efficient for the correction of skeletal Class II irrespective of the maxillary pattern. The mandible had no significant rotation during treatment.


Asunto(s)
Aparatos de Tracción Extraoral , Maloclusión Clase II de Angle/terapia , Niño , Humanos , Maloclusión Clase II de Angle/patología
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