Maxillary dental and skeletal effects after treatment with self-ligating appliance and miniscrew-assisted rapid maxillary expansion.

INTRODUCTION: The objective of the present study was to compare the maxillary dental and skeletal effects after treatment with self-ligating appliance and miniscrew-assisted rapid maxillary expansion (MARPE). METHODS: The sample comprised 37 patients with Class I malocclusion treated without tooth extraction, divided into 2 groups: group 1 comprises 21 patients with a mean age of 19.55 years (standard deviation = 1.31), submitted to orthodontic treatment with Damon self-ligating appliance, and evaluated until the end of the alignment and leveling stage. Group 2 comprises 16 patients with a mean age of 24.92 years (standard deviation = 7.60), with maxillary atresia, who underwent MARPE, and were evaluated after the removal of the expander. Buccal bone thickness; dental inclinations; and transverse distances of the maxillary arch, nasal base, and jugula widths were measured on cone-beam computed tomography scans before and after treatment. The intergroup comparison was performed with the independent t test. RESULTS: With treatment, there was a significantly greater decrease in buccal bone thickness of canines and premolars in the self-ligating group, the premolars presented a greater buccal inclination in the self-ligating group, and the intercanine and intermolar distances and nasal base and jugula widths showed significantly greater increases in the MARPE group than in the self-ligating group. CONCLUSIONS: MARPE treated more severe skeletal transverse maxillary discrepancies and obtained better results than self-ligating appliances in terms of buccal bone loss, tooth inclination, and transverse skeletal increase of the maxilla. MARPE presented more skeletal effects and self-ligating appliances, more dental effects.

Failure rates among metal brackets cured with two high-intensity LED light-curing lamps: an in vivo study.

OBJECTIVE: The objective of this split-mouth clinical trial was to compare bonding failure rates of metal brackets bonded with two different light-emitting diode (LED) light-curing lamps with different high-intensity power outputs. MATERIALS AND METHODS: Forty patients were included for a total of 800 brackets that were randomly bonded (left and right sides in a 1:1 ratio) in maxillary and mandibular arches using two different LED devices. An LED of 3200 mW/cm2 and an LED of 5000 mW/cm2 were used in this split-mouth clinical trial. Bonding failures during the initial 6 months of orthodontic treatment were recorded as maxillary versus mandibular, anterior teeth versus posterior teeth, and left side versus right side. RESULTS: Five dropouts were recorded for discontinuing orthodontic treatment and 700 brackets were analysed in total. The bonding failure rates for 3200 and 5000 mW/cm2 LEDs were 6.0 and 7.4 per cent, respectively (P = 0.450), which were not statistically significantly different. There were no significant differences in bracket survival rates between the LEDs used (P = 0.866). The posterior teeth presented a higher index of bond failures (odds ratio, 3.14; 95% confidence interval, 1.68-5.87; P < 0.001). LIMITATIONS: Direct comparison was only done between two high-intensity LED lights rather than against conventionally used halogen lights. CONCLUSION: Similar bonding failures were recorded using both LED devices (3200 and 5000 mW/cm2). Significantly more bonding failures occurred in premolar teeth than in anterior teeth.

Comparison of gingival display in smile attractiveness among restorative dentists, orthodontists, prosthodontists, periodontists, and laypeople.

STATEMENT OF PROBLEM: Multidisciplinary treatment needs a common goal, and dentists should understand the esthetic perception of laypeople and the other specialists involved. Such information is sparse. PURPOSE: The purpose of this cross-sectional study was to compare the influence of gingival display on perceived smile esthetics among restorative dentists, orthodontists, prosthodontists, periodontists, and laypeople. MATERIAL AND METHODS: Photographs of the smiles of 2 volunteers (1 female and 1 male) were manipulated on a computer to produce gingival exposure of 1, 3, and 5 mm and central incisor coverage of 3 and 5 mm. The images were evaluated by using a 100-mm visual analog scale by 155 raters divided into 5 groups (restorative dentists, orthodontists, prosthodontists, periodontists, and laypeople). RESULTS: The dental specialists, mainly orthodontists and periodontists, were more sensitive about alterations in gingival display than the laypeople. For the female smile, higher mean scores were attributed to 1 mm of gingival exposure by all groups of raters. For the male smile, 3 mm of central incisor coverage received higher mean scores, except for the laypeople, who considered gingival display of 1 mm to be more attractive. For both smiles, 5 mm of gingival display was judged to be the least attractive. CONCLUSIONS: Considering the differences in opinion between dental specialists and laypeople and the acceptable variations in gingival display, the preferences of patients should be considered in the diagnosis and treatment decision-making process.

Maxillary and mandibular dentoalveolar expansion with an auxiliary beta-titanium arch.

Traditionally, adult patients with mild to moderate transverse discrepancies are treated with a combination of slow maxillary expansion with palatal appliances and expanded archwires. In this case report, we describe an alternative approach for anterior crowding and excessive buccal corridors in a 20-year-old man who was treated using a beta-titanium auxiliary expansion archwire. The perceived benefit of this approach was related not only to the esthetic improvement of the smile resulting from elimination of the anterior crowding and reduction of the buccal corridors, but also to the minimal disruption of the patient's speech, which was his main functional concern.

Clinical Efficiency of Two Sequences of Orthodontic Wires to Correct Crowding of the Lower Anterior Teeth.

This study compared time to correction of mandibular anterior crowding using two arch wire sequences, one with conventional nickel-titanium (NiTi) arch wires and the other with conventional and NiTi heat-activated arch wires. Twenty-two boys and girls (mean age: 16.68 ± 2.66) with moderate crowding (3-6 mm) were assigned randomly to one of two groups and followed up for five months (six assessments) when arch wires were changed. Time to crowding correction was analyzed statistically using the Kaplan-Meier method. Data were collected during the five-month follow-up, and time to correction was compared between groups using the log rank test. At the end of follow-up, mandibular crowding was corrected in 100% of the cases in the group treated with the sequence that included NiTi heat-activated arch wires, whereas about 30% of those treated with NiTi arch wires were not completely corrected. There was a significant difference in time to complete treatment between groups (log rank = 5.996; p < 0.05). In the group treated with the sequence that included heat-activated wires, alignment and leveling of mandibular anterior teeth were completed earlier than in the group treated only with conventional NiTi arch wires. Clinical trial registration is found at RBR-7g5zng.

Deflection Evaluation of Thermoactivated Nickel-Titanium Archwires after Heat Treatment on their Distal Ends.

OBJECTIVE: This study evaluated in vitro the mechanical changes of 0.018" (0.45 mm) and 0.016 × 0.022" (0.40 × 0.55 mm) thermoactivated nickel-titanium archwires subjected to heat treatment on their distal ends. MATERIALS AND METHODS: Ten archwires in diameters 0.018" and 0.016 × 0.022" by different manufacturers Ormco, Morelli, Orthometric and Unitek were tested. Each tested archwire had an experimental side, submitted to heat treatment, and an annealing-free control. Tests for load/deflection were performed using a universal testing machine, with temperature control in the austenitic transformation phase through tempe rature-controlled chamber. The variables showed normal distribution (Kolmogorov-Smirnov), the t-student test was applied in order to observe the difference between the experi mental and control groups. Statistical significance was set at p < 0.05. RESULTS: There were no statistically significant differences between the groups. CONCLUSION: Heat treatment carried out in the region corresponding to the first molar distal region on thermoactivated nickel-titanium archwires did not influence the load/deflection values in adjacent portion.

The prestretching effect on the force decay of orthodontic elastic chain.

This in vitro study evaluated the Influence of prestretching, in the force decay of orthodontic elastic chains, at three time intervals: 2, 7 and 30 days with the brands Morelli, Orthometric and American Orthodontics. In the experimental group, prestretching was performed, stretching the elastics to increase them by 50% of their original length three times in a quick and sequential mode. All of the elastic chains were kept stretched and stored in artificial saliva at 37°C until the time of force measurement. For comparisons between the control and experimental groups, the Mann-Whitney test was used. For comparisons between time points and brands, the Kruskal-Wallis test was used, and for multiple comparisons, Miller's post-hoc test was used. The results showed statistically significant differences among the different commercial brands tested at the initial time point. The mean force at the initial time point ranged from 2.57 to 3.17 N. By day 2, the force values were between 0.97 and 1.49 N; by day 7, the values were 0.56 and 0.94 N. By day 30, the force values ranged between 0.27 and 0.66 N. We concluded that performing and duration of prestretching and the brand all Influenced the force decay of orthodontic elastic chains. Time had a greater Influence on the decay of the elastics than brand or prestretching.

Ossification of the midpalatal suture after surgically assisted rapid maxillary expansion.

The purpose of this study was to evaluate ossification of the midpalatal suture in adult patients immediately after surgically assisted rapid maxillary expansion (SARME) until 120 days post-surgery. The sample comprised 126 standardized occlusal radiographs of 21 adults (14 females and 7 males; mean age: 25.33 years) taken pre-expansion (T1), immediately after expansion (T2), and post-expansion (30, 60, 90, and 120 days of retention, respectively: T3, T4, T5, and T6) who had undergone SARME. The radiographs were digitized and the images were analysed and compared in relation to the morphology and radiopacity at the different treatment stages, especially concerning the characteristics of the midpalatal suture. Data were statistically analysed using analysis of variance and Tukey's test. The results demonstrated that from T2 to T6, the mean optical density (OD) increased. However, these values were not similar to those observed at T1. A retention period of 120 days was not sufficient for the re-establishment of OD and complete ossification within the suture in the evaluated patients.

Efficacy of products for bleaching and whitening under orthodontic brackets.

INTRODUCTION: Many patients wearing orthodontic appliances request alterations in the shade of their teeth during orthodontic treatment. OBJECTIVE: This study aimed to evaluate the efficacy of different products for bleaching and whitening under orthodontic brackets. METHODS: Seventy bovine incisors were randomly divided into five groups (n = 14): C) non-whitening toothpaste (control); WTsi) hydrated silica whitening toothpaste; WThp) 2% hydrogen peroxide whitening toothpaste; OB) in-office bleaching; and HB) at-home bleaching. Two buccal surface areas were evaluated using the Easyshade spectrophotometer: under the metal bracket (experimental) and around the bracket (control). The paired t-test, ANOVA, and Tukey tests were applied for statistical analysis. RESULTS: Intragroup comparisons showed that in groups C, WThp and HB, there were statistically significant differences in the enamel color changes (ΔEab) between under and around the bracket areas (C - under bracket = 7.97 ± 2.35, around bracket = 2.86 ± 0.81, p< 0.01; WThp - under bracket = 4.69 ± 2.98, around bracket = 2.05 ± 1.41, p< 0.01; HB - under bracket = 7.41 ± 2.89, around bracket: 9.86 ± 3.32, p= 0.02). Groups WTsi, OB and HB presented similar perception of tooth whiteness (ΔWID) between the tested areas. Intergroup comparisons demonstrated that under the bracket area, the color change (ΔEab) was similar for all groups, except WThp (C = 7.97 ± 2.35; WTsi = 8.54 ± 3.63; WThp = 4.69 ± 2.98; OB = 9.31 ± 4.32; HB = 7.41 ± 2.89; p< 0.01). CONCLUSIONS: The dental color changes were effective for the products tested in groups WTsi, OB and HB in the presence of metallic orthodontic brackets.

Do laypersons perceive aesthetic differences between coated and uncoated orthodontic archwires?

INTRODUCTION: Aesthetic brackets are routinely combined with metallic wires in fixed orthodontic therapy, mainly due to the disadvantages of the clinical use of aesthetic archwires. The current situation needs to be explored in the literature by considering laypersons' perceptions. OBJECTIVE: The objective of this cross-sectional study was to evaluate laypersons' aesthetic perceptions of metal archwires with and without aesthetic coating. Three age ranges and both sexes were evaluated. METHODS: A volunteer using fixed aesthetic orthodontic appliance was photographed wearing the following archwires: stainless steel, nickel-titanium (NiTi), NiTi coated with epoxy resin and NiTi coated with rhodium. Using a 100-mm visual analog scale, 90 laypersons evaluated the photographs. Sex and age ranges (18-30, 31-45, over 46 years of age) were evaluated. The comparisons between the archwires and between age ranges were made using ANOVA and Tukey's test. Genders were compared using Mann-Whitney test. RESULTS: The results showed that the evaluators considered the archwire coated with epoxy resin to be the most aesthetic (60.64 ± 13.04) and the NiTi wire to be the least aesthetic (30.82 ± 7.79) (p< 0.05). Only the range of 31-45 years of age considered the NiTi archwires less aesthetic, when compared with the other age groups. For the other archwires, no statistically significant difference were found between the age groups. No differences between the sexes were detected. CONCLUSIONS: The results indicated that the aesthetic coated archwires represent an improvement in the visual aspect of ceramic brackets. The epoxy-coated metal wire was considered the most aesthetic option.

Efficacy of products for bleaching and whitening under orthodontic brackets

ABSTRACT Introduction: Many patients wearing orthodontic appliances request alterations in the shade of their teeth during orthodontic treatment. Objective: This study aimed to evaluate the efficacy of different products for bleaching and whitening under orthodontic brackets. Methods: Seventy bovine incisors were randomly divided into five groups (n = 14): C) non-whitening toothpaste (control); WTsi) hydrated silica whitening toothpaste; WThp) 2% hydrogen peroxide whitening toothpaste; OB) in-office bleaching; and HB) at-home bleaching. Two buccal surface areas were evaluated using the Easyshade spectrophotometer: under the metal bracket (experimental) and around the bracket (control). The paired t-test, ANOVA, and Tukey tests were applied for statistical analysis. Results: Intragroup comparisons showed that in groups C, WThp and HB, there were statistically significant differences in the enamel color changes (ΔEab) between under and around the bracket areas (C - under bracket = 7.97 ± 2.35, around bracket = 2.86 ± 0.81, p< 0.01; WThp - under bracket = 4.69 ± 2.98, around bracket = 2.05 ± 1.41, p< 0.01; HB - under bracket = 7.41 ± 2.89, around bracket: 9.86 ± 3.32, p= 0.02). Groups WTsi, OB and HB presented similar perception of tooth whiteness (ΔWID) between the tested areas. Intergroup comparisons demonstrated that under the bracket area, the color change (ΔEab) was similar for all groups, except WThp (C = 7.97 ± 2.35; WTsi = 8.54 ± 3.63; WThp = 4.69 ± 2.98; OB = 9.31 ± 4.32; HB = 7.41 ± 2.89; p< 0.01). Conclusions: The dental color changes were effective for the products tested in groups WTsi, OB and HB in the presence of metallic orthodontic brackets.

RESUMO Introdução: Durante o tratamento ortodôntico, muitos pacientes solicitam, também, alteração na cor dos seus dentes. Objetivo: O presente estudo avaliou diferentes produtos clareadores e branqueadores, quanto à sua eficácia sob os braquetes ortodônticos. Métodos: 70 incisivos bovinos foram aleatoriamente divididos em cinco grupos (n = 14): C) dentifrício não branqueador (controle); WTsi) dentifrício branqueador com sílica hidratada; WThp) dentifrício branqueador com peróxido de hidrogênio a 2%; OB) clareamento no consultório e HB) clareamento caseiro. Usando um espectrofotômetro Easyshade, foram avaliadas duas áreas na superfície vestibular dos dentes: sob o braquete (experimental) e ao redor do braquete (controle). Para análise estatística, foram usados os testest pareado, ANOVA e Tukey. Resultados: As comparações intragrupos demonstraram que, nos grupos C, WThp e HB, ocorreram diferenças estatisticamente significativas nas alterações de cor do esmalte (ΔEab) entre as áreas sob o braquete e ao redor do braquete (C: sob o braquete = 7,97 ± 2,35, ao redor do braquete = 2,86 ± 0,81, p< 0,01; WThp: sob o braquete = 4,69 ± 2,98, ao redor do braquete = 2,05 ± 1,41, p< 0,01; HB: sob o braquete = 7,41 ± 2,89, ao redor do braquete = 9,86 ± 3,32, p= 0,02). Os grupos WTsi, OB e HB demonstraram semelhanças na percepção do clareamento (ΔWID) entre as áreas avaliadas. As comparações intergrupos demonstraram que, nas áreas sob os braquetes, as alterações de cor (ΔEab) foram semelhantes para os grupos, com exceção do WThp (C = 7,97 ± 2,35; WTsi = 8,54 ± 3,63; WThp = 4,69 ± 2,98; OB = 9,31 ± 4,32; HB = 7,41 ± 2,89; p< 0,01). Conclusões: As alterações na cor dos dentes foram efetivas para os procedimentos testados nos grupos WTsi, OB e HB na presença de braquetes metálicos ortodônticos.

Identificação perceptiva do posicionamento da língua na produção de [s] por acadêmicos em Fonoaudiologia / Identificación perceptiva del posicionamiento de la lengua de la producción de [s] por académicos en Fonoaudiología / Perceptual analysis of the tongue position in the production of [s] by SLP students

Introdução: a identificação visual do posicionamento dos articuladores e o resultado auditivo na produção de [s] são necessários para decisões clínicas e monitoramento de tratamento. Para avaliadores não treinados esta tarefa pode ser desafiadora. Objetivo: verificar se avaliadores não treinados são capazes de identificar visualmente posições normal e alterada da língua na produção do [s] e perceber, auditivamente, produções normais e alteradas; bem como buscar quais ajustes da língua são mais difíceis de serem percebidos visualmente e quais resultados auditivos são mais facilmente identificados. Método: dez acadêmicos de Fonoaudiologia analisaram 20 amostras de fala gravadas, 10 com produção normal e 10 alterada do fone [s], sendo as respostas comparadas a uma avaliação padrão-ouro. Na análise foi utilizada a concordância Kappa, o teste Qui-quadrado, o Anova de Medidas repetidas e o teste t Student, com 5% de significância. Resultados: houve associação e concordância com a avaliação padrão-ouro para a posição da língua, com porcentagem média de 40% de respostas corretas para a posição normal, 17,5% quando a língua estava contra os dentes e 10% quando interposta. No resultado auditivo, a maioria dos avaliadores não apresentou associação e concordância com o padrão-ouro, sendo a porcentagem média de 50% de respostas corretas na ausência de distorção e com redução significativa quando presente (18,5%). Conclusão: os acadêmicos tiveram dificuldade na identificação visual da posição da língua, particularmente, quando alterada, bem como na identificação auditiva das produções normal ou alterada, sendo maior quando a distorção estava presente.

Introduction: thevisual identification of articulator positioning and auditory perception in the phoneme [s] are needed for clinical decisions and treatment monitoring. This can be challenging for untrained evaluators. Objective: to verify whether untrained evaluators are able to visually identify typical and atypical tongue positions in the production of phoneme [s] and to auditorily perceive typical and atypical productions; as well as to understand which tongue adjustments are more difficult to be visually perceived and which auditory productions are more easily identified. Methods: ten speech-language pathology students analyzed 20 recorded speech samples, being 10 with typical speech production and 10 atypical speech production regarding the [s] movement, and the answers were compared with a gold-standard evaluation. The Kappa agreement, Chi-squared test, Anova repeated measures and Student ́s t-test were used with 5% of significance. Results: there was an association and agreement with the gold standard evaluation for tongue positioning, with a mean percentage of 40% for correct answers regarding typical position, 17.5% when the tongue was against the teeth and 10% when interposed. In the auditory perception; most evaluators did not show association and agreement with the gold standard evaluation, with an average percentage of 50% for correct answers in the absence of distortion and a significant reduction in the presence (18.5%). Conclusion: the students had difficulty in the visual identification of the tongue positioning for atypical speech productions, as well as in the auditory identification of typical or atypical productions, and the greater difficulty occurred when there was distortion.

Introducción: identificar visualmente el posicionamiento del articulador y el resultado auditivo en la producción del [s] son necesarios para tomar decisiones clínicas y monitorear el tratamiento. Objetivo:verificar si los evaluadores no capacitados pueden identificar visualmente las posiciones normales y alteradas de la lengua en la producción del [s] y percibir auditivamente las producciones normales y alteradas; además buscar qué ajustes de la lengua son más difíciles de percibir visualmente y qué resultados auditivos se identifican más fácilmente. Método: estudiantes de Fonoaudiología analizaron 20 muestras de habla grabadas, 10 con producción normal y 10 con producción del fono [s] alterado. Compararon las respuestas con una evaluación patrón oro. En el análisis utilizaron la concordancia Kappa, la prueba Chi-cuadrado, el Anova de Medidas repetidas y la prueba t de Student, con 5% de significancia. Resultados:hubo asociación y concordancia con la evaluación patrón oro para la posición de la lengua, con media de 40% de respuestas correctas para la posición normal, 17,5% con la lengua contra los dientes y 10% cuando interpuesta. En el resultado auditivo, la mayoría de los evaluadores no presentaron asociación y concordancia con el patrón oro, con media de 50% de aciertos en ausencia de distorsión y con reducción significativa cuando presente (18,5%). Conclusión: los estudiantes tuvieron dificultad en identificar visualmente la posición de la lengua, particularmente cuando alterada, y en la identificación auditiva de producciones normales o alteradas, siendo mayor con la distorsión presente.

Effect of vertical placement angle on the insertion torque of mini-implants in human alveolar bone.

OBJECTIVE:: The aim of the present ex-vivo study was to evaluate the effect of the vertical placement angle of mini-implants on primary stability by analyzing maximum insertion torque (MIT). METHODS:: Mini-implants were placed in 30 human cadavers, inserted at either a 90° or 60° angle to the buccal surface of the maxillary first molar. Out of 60 self-drilling mini-implants used, half were of the cylindrical type and half were of the conical type. Primary stability was assessed by means of measuring the MIT. Data were subjected to analysis of variance (ANOVA) and Newman-Keuls tests. A significance level of 5% was adopted. RESULTS:: The MIT was higher for both mini-implant types when they were placed at a 90° angle (17.27 and 14.40 Ncm) compared with those placed at a 60° angle (14.13 and 11.40 Ncm). CONCLUSIONS:: MIT values were differed according to the vertical mini-implant placement angle in the maxillary posterior area. Regardless of the type of mini-implant used, placement at a 90° angle resulted in a higher MIT.

The influence of distal-end heat treatment on deflection of nickel-titanium archwire.

OBJECTIVE: The aim of this in vitro study was to evaluate the deflection-force behavior of nickel-titanium (NiTi) orthodontic wires adjacent to the portion submitted to heat treatment. MATERIAL AND METHODS: A total of 106 segments of NiTi wires (0.019 x 0.025-in) and heat-activated NiTi wires (0.016 x 0.022-in) from four commercial brands were tested. The segments were obtained from 80 archwires. For the experimental group, the distal portion of each segmented archwire was subjected to heat treatment (n = 40), while the other distal portion of the same archwire was used as a heating-free control group (n = 40). Deflection tests were performed in a temperature-controlled universal testing machine. Unpaired Student's t-tests were applied to determine if there were differences between the experimental and control groups for each commercial brand and size of wire. Statistical significance was set at p < 0.05. RESULTS: There were no statistically significant differences between the tested groups with the same size and brand of wire. CONCLUSIONS: Heat treatment applied to the distal ends of rectangular NiTi archwires does not permanently change the elastic properties of the adjacent portions.

Deflection test evaluation of different lots of the same nickel-titanium wire commercial brand.

INTRODUCTION: The aim of this in vitro study was to compare the elastic properties of the load-deflection ratio of orthodontic wires of different lot numbers and the same commercial brand. METHODS: A total of 40 nickel-titanium (NiTi) wire segments (Morelli Ortodontia™--Sorocaba, SP, Brazil), 0.016-in in diameter were used. Groups were sorted according to lot numbers (lots 1, 2, 3 and 4). 28-mm length segments from the straight portion (ends) of archwires were used. Deflection tests were performed in an EMIC universal testing machine with 5-N load cell at 1 mm/minute speed. Force at deactivation was recorded at 0.5, 1, 2 and 3 mm deflection. Analysis of variance (ANOVA) was used to compare differences between group means. RESULTS: When comparing the force of groups at the same deflection (3, 2 and 1 mm), during deactivation, no statistical differences were found. CONCLUSION: There are no changes in the elastic properties of different lots of the same commercial brand; thus, the use of different lots of the orthodontic wires used in this research does not compromise the final outcomes of the load-deflection ratio.

Evaluation of an alternative technique to optimize direct bonding of orthodontic brackets to temporary crowns.

OBJECTIVE: To compare shear bond strength of different direct bonding techniques of orthodontic brackets to acrylic resin surfaces. METHODS: The sample comprised 64 discs of chemically activated acrylic resin (CAAR) randomly divided into four groups: discs in group 1 were bonded by means of light-cured composite resin (conventional adhesive); discs in group 2 had surfaces roughened with a diamond bur followed by conventional direct bonding by means of light-cured composite resin; discs in group 3 were bonded by means of CAAR (alternative adhesive); and discs in group 4 had surfaces roughened with a diamond bur followed by direct bonding by means of CAAR. Shear bond strength values were determined after 24 hours by means of a universal testing machine at a speed of 0.5 mm/min, and compared by analysis of variance followed by post-hoc Tukey test. Adhesive remnant index (ARI) was measured and compared among groups by means of Kruskal-Wallis and Dunn tests. RESULTS: Groups 3 and 4 had significantly greater shear bond strength values in comparison to groups 1 and 2. Groups 3 and 4 yielded similar results. Group 2 showed better results when compared to group 1. In ARI analyses, groups 1 and 2 predominantly exhibited a score equal to 0, whereas groups 3 and 4 predominantly exhibited a score equal to 3. CONCLUSIONS: Direct bonding of brackets to acrylic resin surfaces using CAAR yielded better results than light-cured composite resin. Surface preparation with diamond bur only increased shear bond strength in group 2.

Do laypersons perceive aesthetic differences between coated and uncoated orthodontic archwires?

ABSTRACT Introduction: Aesthetic brackets are routinely combined with metallic wires in fixed orthodontic therapy, mainly due to the disadvantages of the clinical use of aesthetic archwires. The current situation needs to be explored in the literature by considering laypersons' perceptions. Objective: The objective of this cross-sectional study was to evaluate laypersons' aesthetic perceptions of metal archwires with and without aesthetic coating. Three age ranges and both sexes were evaluated. Methods: A volunteer using fixed aesthetic orthodontic appliance was photographed wearing the following archwires: stainless steel, nickel-titanium (NiTi), NiTi coated with epoxy resin and NiTi coated with rhodium. Using a 100-mm visual analog scale, 90 laypersons evaluated the photographs. Sex and age ranges (18-30, 31-45, over 46 years of age) were evaluated. The comparisons between the archwires and between age ranges were made using ANOVA and Tukey's test. Genders were compared using Mann-Whitney test. Results: The results showed that the evaluators considered the archwire coated with epoxy resin to be the most aesthetic (60.64 ± 13.04) and the NiTi wire to be the least aesthetic (30.82 ± 7.79) (p< 0.05). Only the range of 31-45 years of age considered the NiTi archwires less aesthetic, when compared with the other age groups. For the other archwires, no statistically significant difference were found between the age groups. No differences between the sexes were detected. Conclusions: The results indicated that the aesthetic coated archwires represent an improvement in the visual aspect of ceramic brackets. The epoxy-coated metal wire was considered the most aesthetic option.

RESUMO Introdução: rotineiramente na terapia ortodôntica fixa, utilizam-se braquetes estéticos combinados com fios metálicos, principalmente devido a algumas desvantagens no uso clínico dos fios estéticos. A percepção estética dos leigos nessa situação precisa ser explorada na literatura. Objetivo: o objetivo deste estudo transversal foi avaliar a percepção estética dos leigos em relação aos fios ortodônticos metálicos recobertos ou não por materiais estéticos. Três faixas etárias, dos dois sexos, foram avaliadas. Métodos: uma paciente usando aparelho ortodôntico fixo estético foi fotografada com os seguintes fios ortodônticos: aço inoxidável, níquel-titânio (NiTi), NiTi recoberto por resina epóxica e NiTi recoberto por ródio. As fotografias foram avaliadas por 90 leigos, utilizando-se uma escala visual analógica de 100-mm. Ambos os sexos e diferentes faixas etárias (18-30, 31-45 e acima de 46 anos) foram avaliados. As comparações entre os fios e entre as faixas etárias foram realizadas aplicando-se os testes ANOVA e Tukey. Os sexos foram comparados utilizando-se o teste de Mann-Whitney. Resultados: os resultados demonstraram que os avaliadores consideraram o fio recoberto por resina epóxica como o mais estético (60,64 ± 13,04) e o fio de NiTi foi classificado como o menos estético (30,82 ± 7,79) (p< 0,05). Apenas a faixa etária de 31-45 anos considerou o fio de NiTi menos estético, quando comparada às outras faixas etárias; para os outros fios, não foi observada diferença estatisticamente significativa entre as faixas etárias. Não foi detectada diferença entre os sexos. Conclusões: os resultados indicaram que os fios estéticos recobertos melhoraram o aspecto visual dos braquetes cerâmicos. O fio metálico recoberto por resina epóxica foi considerado a opção mais estética.

Distalization of maxillary molars using a lever arm and mini-implant.

This article describes the orthodontic treatment of a young woman with a Class II malocclusion and maxillomandibular prognathism. One orthodontic mini- implant was placed in the posterior area of the palate to provide anchorage for?a transpalatal arch. The force for molar distalization was applied using an elastic chain from the lever arm inserted on the transpalatal arch to the mini-implant. Two sliding jigs were applied buccally as a complement for Class II malocclusion correction. This system created an efficient mechanotherapy for maxillary molar distalization. The active treatment period was 19 months. Normal overjet and reduction of maxillomandibular prognathism were obtained, and labial balance was improved.

Reliability and accuracy of a radiographic analysis method for posterior maxillary mini-implant location.

OBJECTIVE: The purpose of this study was to evaluate the reliability and accuracy of a radiographic analysis method for the location of mini-implants inserted in the posterior region of the maxilla. MATERIAL AND METHODS: Two self-drilling mini-implants were installed between the second premolar and the first molar on the right side and left side in three dry skulls. Three operators performed three occlusal radiographs, using an occlusal x-ray film holder, at three different times in each of the three skulls. RESULTS: The interclass correlation coefficient showed a significantly high, positive correlation (p<0.05), indicating an excellent reliability between operators. The analysis of variance showed no significant differences in time and among the operators. CONCLUSION: Based of these findings, it may be concluded that this methodology can be used by several operators in longitudinal clinical studies on orthodontic mini-implants at the anterior-posterior and lateral-medial locations or longitudinal displacement.

The influence of distal-end heat treatment on deflection of nickel-titanium archwire

Objective: The aim of this in vitro study was to evaluate the deflection-force behavior of nickel-titanium (NiTi) orthodontic wires adjacent to the portion submitted to heat treatment. Material and Methods: A total of 106 segments of NiTi wires (0.019 x 0.025-in) and heat-activated NiTi wires (0.016 x 0.022-in) from four commercial brands were tested. The segments were obtained from 80 archwires. For the experimental group, the distal portion of each segmented archwire was subjected to heat treatment (n = 40), while the other distal portion of the same archwire was used as a heating-free control group (n = 40). Deflection tests were performed in a temperature-controlled universal testing machine. Unpaired Student's t-tests were applied to determine if there were differences between the experimental and control groups for each commercial brand and size of wire. Statistical significance was set at p < 0.05. Results: There were no statistically significant differences between the tested groups with the same size and brand of wire. Conclusions: Heat treatment applied to the distal ends of rectangular NiTi archwires does not permanently change the elastic properties of the adjacent portions.

Objetivo: o objetivo dessa pesquisa in vitro foi avaliar a deflexão na porção adjacente à área do tratamento térmico realizado no extremo distal de fios ortodônticos de níquel-titânio (NiTi). Métodos: foram testados 160 segmentos de fios de NiTi (0,019" x 0,025") e NiTi termoativado (0,016" x 0,022") de quatro marcas comerciais; obtidos de 80 arcos. No grupo experimental (n = 40), realizou-se o tratamento térmico no extremo distal; enquanto no grupo controle (n = 40), o extremo distal foi mantido isento de tratamento térmico. Os testes de deflexão foram realizados em máquina universal de ensaios, com controle de temperatura. Foi aplicado o teste t de Student não-pareado, visando observar a diferença entre os grupos experimental e controle, em cada espessura e marca. A significância estatística foi fixada com valor dep < 0,05. Resultados: não foram encontradas diferenças estatisticamente significativas entre os grupos testados, de mesma espessura e marca comercial. Conclusão: conclui-se que o tratamento térmico não influenciou na deflexão da região adjacente à extremidade de fios de NiTi submetidos ao tratamento térmico.