The Effect of Motivational Interviewing on Oral Hygiene Behavior in Patients With Fixed Orthodontic Appliances: A Randomised Clinical Trial

The aim of this study was to evaluate the effectiveness of motivational interviewing on improving oral hygiene behavior in patients with fixed orthodontics appliances. A parallel-group randomized clinical trial was conducted with 45 patients of the Orthodontic Clinic of Unibe's Postgraduate Unit. A computer-generated list of numbers created with SPSS V21.0 was used to randomly allocate participants into the experimental or the control group. Monthly oral hygiene instructions and an oral hygiene kit from GUM® with special orthodontic hygiene tools were given to the participants. Furthermore, the experimental group underwent motivational interviewing sessions facilitated by a periodontist who received training from two expert psychologists. These psychologists also provided supervision to the interviewer, ensuring the accurate implementation of the intervention. Simplified Oral Hygiene Index (SOHI), Gingival Index (GI), Periodontal Probing Depth (PPD) and Bleeding on Probing (BoP) were recorded at baseline, three and six months after the beginning of the study. The participant and the evaluator (another periodontist who recorded the data) were masked. Repeated-measures mixed- model analysis of variance and chi-squared test were conducted. Mean SOHI, GI, PPD and BoP scores did not differ significantly across the three time points (baseline, three and six months). Nevertheless, a significant interaction on SOHI scores (F (2, 58) = 3.463, p = .038, h2 = .052) was found between the sessions and the treatment conditions (experimental vs control group) at the third and sixth month. Motivational interviewing plus oral hygiene instructions appears to maintain a better control of dental biofilm and calculus in comparison with conventional oral hygiene instructions alone.

El objetivo de este trabajo fue evaluar la efectividad de las entrevistas motivacionales para mejorar el comportamiento de higiene oral en pacientes con aparatos ortodóncicos fijos. Se llevó a cabo un ensayo clínico aleatorizado de grupos paralelos con 45 pacientes de la Clínica de Ortodoncia de la Unidad de Posgrado de Unibe. Se utilizó una lista de números generada por computadora con SPSS V21.0 para asignar aleatoriamente a los participantes al grupo experimental o de control. Se les proporcionó a los participantes instrucciones mensuales de higiene oral y un kit de higiene oral de GUM® con utensilios de higiene especiales para ortodoncia. Además, el grupo experimental recibió sesiones de entrevista motivacional facilitadas por un periodoncista capacitado por dos psicólogas expertas. Estas psicólogas también supervisaron al entrevistador, asegurando la implementación precisa de la intervención. Se registró el Índice Simplificado de Higiene Oral (IHO-S), el Índice Gingival (IG), la Profundidad de Sondaje Periodontal (PS) y el Sangrado al Sondaje (SS) al inicio, a los tres y seis meses después del inicio del estudio. Tanto el participante como el evaluador (otro periodoncista que registró los datos) estaban enmascarados. Se realizaron análisis de varianza de medidas repetidas con modelo mixto y pruebas de chi-cuadrado. Las puntuaciones medias del IHO-S, IG, PS y SS no difirieron significativamente en los tres momentos (inicio, tres y seis meses). Sin embargo, se encontró una interacción significativa en las puntuaciones del IHO-S (F (2, 58) = 3.463, p = .038, h2 = .052) entre las sesiones y las condiciones de tratamiento (grupo experimental vs grupo de control) en el tercer y sexto mes. Las entrevistas motivacionales junto con las instrucciones de higiene oral parecen mantener un mejor control de la biopelícula dental y el cálculo en comparación con las instrucciones convencionales de higiene oral por sí solas.

Meta-analysis of the efficacy of invisible orthodontic appliances for maxillary molar distalization in adult patients / 口腔疾病防治

Objective@#To evaluate the clinical efficacy of invisible orthodontic appliances without brackets for the distal movement of maxillary molars to improve the ability of orthodontists to predict treatment outcomes.@*Methods@#Web of Science, Cochrane Library, Embase, PubMed, Wanfang Database, CNKI Database, and VIP Database were searched for studies investigating the efficacy of invisible orthodontic appliances for distal movement of maxillary molars in adult patients and published from database inception to August 1, 2023. A total of three researchers screened the studies and evaluated their quality and conducted a meta-analysis of those that met quality standards.@*Results@#This study included 13 pre- and postcontrol trials with a total sample size of 281 patients. The meta-analysis revealed no significant differences in the sagittal or vertical parameters of the jawbone after treatment when compared with those before treatment (P>0.05). The displacement of the first molar was MD=-2.34, 95% CI (-2.83, -1.85); the displacement was MD=-0.95, 95% CI (-1.34, -0.56); and the inclination was MD=-2.51, 95% CI (-3.56, -1.46). There was a statistically significant difference in the change in sagittal, vertical, and axial tilt of the first molar before and after treatment. After treatment, the average adduction distance of the incisors was MD=-0.82, 95% CI (-1.54, -0.09), and the decrease in lip inclination was MD=-1.61, 95% CI (-2.86, -0.36); these values were significantly different from those before treatment (P<0.05).@*Conclusion@#Invisible orthodontic appliances can effectively move the upper molars in a distal direction and control the vertical position of the molars. When the molars move further away, there is some degree of compression and distal tilt movement, which is beneficial for patients with high angles. The sagittal movement of incisors is beneficial for improving the patient's profile.

The effects of invisible orthodontic appliances without brackets and labial fixed orthodontic appliances on periodontal status and root resorption in orthodontic patients / 中国医师杂志

Objective:To compare the effects of invisible orthodontic appliances without brackets and labial fixed orthodontic appliances on periodontal status and root resorption in orthodontic patients.Methods:A retrospective study was conducted on 102 orthodontic patients who visited the Affiliated Hospital of Jining Medical University from January 2019 to October 2022. According to different treatment methods, they were divided into group A ( n=52) and group B ( n=50). Group A was treated with invisible orthodontic appliances without brackets, while group B was treated with labial fixed orthodontic appliances. We compared two groups of treatment completion time, root resorption, and periodontal health indicators before and after treatment, including plaque index (PLI), gingival index (GI), gingival sulcus bleeding index (SBI), and levels of inflammatory factors in gingival crevicular fluid, including interleukin-1β (IL-1β) and soluble intercellular adhesion molecule-1 (sICAM-1). Results:The completion time of treatment in the Group A was longer than that in the group B [(34.62±4.28)months vs (28.93±3.11)months] ( P<0.01). After treatment, the incidence of root resorption in the group A was 50.96%, while in the group B it was 78.00%. The group A was significantly lower than the group B ( P<0.05), with no root resorption greater than 3 mm in the group A and 0.50% in the group B. After treatment, the levels of PLI, GI, SBI, and IL-1β and sICAM-1 in gingival crevicular fluid increased in both groups, with the group A being lower than group B [(1.26±0.39)points vs (1.73±0.54)points, (1.33±0.25)points vs (2.06±0.46)points, (1.73±0.40)points vs (2.48±0.50)points, (173.74±25.81)ng/ml vs (196.33±31.52)ng/ml, (42.28±5.16)μg/L vs (56.59±7.38)μg/L] (all P<0.05). Conclusions:Although invisible orthodontic appliances without brackets cannot shorten the completion time of treatment, they have advantages in inhibiting root resorption, improving periodontal health, and reducing inflammatory reactions. Clinically, appropriate appliances can be selected based on the specific situation of patients.

Methodological Quality of Systematic Reviews Addressing Orthodontic Interventions: Methodological Study

ABSTRACT Objective: To assess the methodological quality and characteristics of systematic reviews (SRs) of interventional studies in orthodontics and assess how the certainty of the evidence is reported using the GRADE approach. Material and Methods: Six electronic databases were searched, followed by a hand search of the reference lists of eligible studies (PROSPERO #CRD42020180852). The required study design was randomized and nonrandomized studies of interventions published between January 2019 and May 2020. The Assessing the Methodological Quality of Systematic Reviews (AMSTAR 2) tool was used for the quality appraisal of the included SRs. Paired reviewers independently screened the studies, extracted data, and appraised the methodological quality. Results: The study included 46 SRs; 19.5% had moderate to high methodological quality, and the remaining had low to critically low methodological quality. Fifty-four percent of the reviews assessed the certainty of evidence using the GRADE approach, and 34.8% followed all GRADE criteria. Conclusion: Most reviews had a good judgment of the AMSTAR2 items, although some critical items contributed to decreased overall quality. Half of the reviews used the GRADE approach to assess the certainty of the evidence, and this approach should be included in future systematic reviews of interventions.

Changes in the arch width and buccal corridor after fixed orthodontic treatment with Damon self-ligating system: premolar extraction vs. non-extraction

ABSTRACT Introduction: Extraction vs. non-extraction is a crucial decision in orthodontic therapy. Objective: The aim of the present study was to investigate the changes in the dental arch width and buccal corridor after orthodontic treatment using extraction and non-extraction therapy with Damon self-ligating system. Material and Methods: This retrospective study consisted of 35 patients (20 female and 15 male patients with median age of 12.5 years), treated by extracting 4 or 2 premolars, and 37 patients (16 female and 21 male patients with the median age of 12.8 years), treated without premolar extraction. Both groups were treated with Damon self-ligating system. Plaster models before (T0) and after (T1) treatment were measured, and the arch width values were determined at the level of the first molars, second premolars, canines and palatal rugae. Buccal corridor width was measured using the extraoral images at T0 and T1. Paired t-test was used for the analysis of the normally distributed data, and Wilcoxon Mann-Whitney U test was used for the data with non-normal distribution. Values of p<0.05 were set as statistically significant. Results: The upper intercanine width increased significantly in both groups (p<0.01). In the non-extraction group, the arch width increased significantly in the maxillary second premolar and first molar region (p<0.01) as well as in the region of the canines (p=0.04), second premolars (p=0.01) and first molars (p<0.01) of the mandible. The buccal corridor decreased significantly in the non-extraction group (p<0.01). Conclusion: Premolar extraction in combination with Damon self-ligating system did not lead to reduction of the dental arch width in the maxilla, nor did it increase the size of the buccal corridors.

RESUMO Introdução: Extrair ou não extrair dentes é uma decisão crucial no tratamento ortodôntico. Objetivo: O objetivo do presente estudo foi investigar as alterações na largura da arcada dentária e no corredor bucal após o tratamento ortodôntico com extração e o tratamento sem extração com o sistema autoligável Damon. Material e Métodos: Esse estudo retrospectivo consistiu de 35 pacientes (20 do sexo feminino e 15 do sexo masculino, com idade média de 12,5 anos), tratados com extração de 4 ou 2 pré-molares; e 37 pacientes (16 do sexo feminino e 21 do sexo masculino, com idade média de 12,8 anos), tratados sem extração de pré-molares. Ambos os grupos foram tratados com o sistema autoligável Damon. Os modelos de gesso antes (T0) e depois (T1) do tratamento foram medidos, e os valores de largura da arcada foram determinados ao nível dos primeiros molares, segundos pré-molares, caninos e rugas palatinas. A largura do corredor bucal foi medida usando as imagens extrabucais em T0 e T1. O teste t pareado foi usado para a análise dos dados com distribuição normal, e o teste U de Wilcoxon Mann-Whitney foi usado para os dados com distribuição não normal. Valores de p < 0,05 foram considerados estatisticamente significativos. Resultados: A distância intercaninos superiores aumentou significativamente em ambos os grupos (p<0,01). No grupo sem extração, a largura da arcada aumentou significativamente na região dos segundos pré-molares e primeiros molares superiores (p<0,01), bem como na região dos caninos (p=0,04), segundos pré-molares (p=0,01) e primeiros molares (p<0,01) inferiores. O corredor bucal diminuiu significativamente no grupo sem extração (p<0,01). Conclusão: A extração de pré-molares em combinação com o sistema autoligável Damon não levou à redução na largura da arcada dentária superior, nem aumentou o tamanho dos corredores bucais.

Accuracy of arch expansion with two thermoplastic materials in Invisalign® patients: EX30® and SmartTrack®

ABSTRACT Objective: The purpose of this retrospective study was to compare accuracy of arch expansion using two different thermoplastic materials in Invisalign aligners: EX30® (Polyethylene Terephthalate Glycol, or PETG) and SmartTrack® (polyurethane). Methods: The study sample comprised 65 adult patients consecutively treated with Invisalign from two private practices: group 1 - treated with EX30® (358 teeth) and group 2 - treated with SmartTrack® (888 teeth). Six hundred and twenty-three measurements were assessed in three digital models throughout treatment: model 1 - initial, model 2 - predicted tooth position, and model 3 - achieved position. Sixteen reference points per arch were marked and, after best alignment, 2 points per tooth were copied from one digital model to another. Linear values of both arches were measured for canines, premolars, and first molars: on lingual gingival margins and cusp tips of every tooth. Comparisons were performed by Wilcoxon and Mann-Whitney test. Results: Both termoplastic materials presented significant differences between predicted and achieved values for all measurements, except for the lower molar cusp tip in the SmartTrack® group. There is no statistical difference in the accuracy of transverse expansion between these two materials. Overall accuracy for EX30® aligners in maxilla and mandible were found to be 37 and 38%, respectively; and Smarttrack® presented an overall accuracy of 56.62% in the maxilla and 68.72% in the mandible. Conclusions: It is not possible to affirm one material expands better than the other. Further controlled clinical studies should be conducted comparing SmartTrack® and EX30® under similar conditions.

RESUMO Objetivo: O objetivo deste estudo retrospectivo foi comparar a acurácia na expansão da arcada utilizando alinhadores Invisalign com dois tipos de material termoplástico: EX30® (Polietileno Tereftalato Glicol, ou PETG) e SmartTrack® (poliuretano). Método: A amostra desse estudo incluiu 65 pacientes adultos tratados consecutivamente em dois consultórios particulares: grupo 1 - tratado com EX30® (358 dentes), e grupo 2 - tratado com SmartTrack® (888 dentes). Foram avaliadas 623 medidas em três pares de modelos digitais, ao longo do tratamento: modelo 1 - inicial, modelo 2 - posição dentária planejada, modelo 3 - posição alcançada. Foram marcados 16 pontos de referência por arcada e, após o bestfit, 2 pontos por arcada foram copiados de um modelo digital para o outro. Medidas lineares de ambas as arcadas foram aferidas para caninos, pré-molares e primeiros molares, localizadas na margem gengival lingual e ponta de cúspide de todos os dentes. Foram realizadas comparações usando os testes Wilcoxon e Mann-Whitney. Resultados: Ambos os materiais termoplásticos apresentaram diferenças significativas entre os valores planejados e alcançados em todas as medidas, exceto na ponta de cúspide dos primeiros molares inferiores do grupo SmartTrack®. Não houve diferença estatística entre esses dois materiais quanto à acurácia da expansão transversa. Em termos gerais, a acurácia dos alinhadores EX30® na maxila e mandíbula foi de 37% e 38%, respectivamente. O grupo SmartTrack® apresentou acurácia de 56,62% e 68,72% na maxila e mandíbula, respectivamente. Conclusões: Não foi possível afirmar que um material expande melhor que o outro. Estudos clínicos controlados futuros devem ser conduzidos comparando SmartTrack® e EX30® sob condições similares.

Insertion torque, flexural strength and surface alterations of stainless steel and titanium alloy orthodontic mini-implants: an in vitro study

ABSTRACT Objective: This study aimed to compare the insertion torque (IT), flexural strength (FS) and surface alterations between stainless steel (SS-MIs) and titanium alloy (Ti-MIs) orthodontic mini-implants. Methods: Twenty-four MIs (2 x 10 mm; SS-MIs, n = 12; Ti-MIs, n = 12) were inserted on artificial bone blocks of 20 lb/ft3 (20 PCF) and 40 lb/ft3 (40 PCF) density. The maximum IT was recorded using a digital torque meter. FS was evaluated at 2, 3 and 4 mm-deflection. Surface topography and chemical composition of MIs were assessed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). General linear and mixed models were used to assess the effect of the MI type, bone density and deflection on the evaluated outcomes. Results: The IT of Ti-MIs was 1.1 Ncm greater than that obtained for the SS-MIs (p= 0.018). The IT for MIs inserted in 40 PCF test blocks was 5.4 Ncm greater than that for those inserted in 20 PCF test blocks (p < 0.001). SS-MIs inserted in higher density bone (40 PCF) had significantly higher flexural strength than the other groups, at 2 mm (98.7 ± 5.1 Ncm), 3 mm (112.0 ± 3.9 Ncm) and 4 mm (120.0 ± 3.4 Ncm) of deflection (p< 0.001). SEM evidenced fractures in the Ti-MIs. EDS revealed incorporation of 18% of C and 2.06% of O in the loaded SS-MIs, and 3.91% of C in the loaded Ti-MIs. Conclusions: Based on the findings of this in vitro study, it seems that SS-MIs offer sufficient stability and exhibit greater mechanical strength, compared to Ti-MIs when inserted into higher density bone.

RESUMO Objetivo: O objetivo deste estudo foi comparar o torque de inserção (TI), a resistência flexural (RF) e as alterações de superfície em mini-implantes ortodônticos de aço inoxidável (MIs-Ai) e de liga de titânio (MIs-Ti). Métodos: Vinte e quatro MIs (2 x 10 mm; MIs-Ai, n = 12; MIs-Ti, n = 12) foram inseridos em blocos de osso artificial de densidades de 20 lb/ft3 (20 PCF) e 40 lb/ft3 (40 PCF). O torque máximo de inserção foi registrado por meio de um torquímetro digital. A resistência flexural foi avaliada nas deflexões de 2, 3 e 4 mm. Topografia de superfície e composição química dos MIs foram avaliadas por Microscopia Eletrônica de Varredura (MEV) e Espectroscopia de Energia Dispersiva de Raios X (EDS). Modelos lineares gerais e mistos foram utilizados para avaliar o efeito do tipo de MI, da densidade óssea e da deflexão nos desfechos avaliados. Resultados: O TI dos MIs-Ti foi 1,1 Ncm maior do que o obtido para os MIs-Ai (P = 0,018). O TI para MIs inseridos em blocos de teste de 40 PCF foi 5,4 Ncm maior do que para aqueles inseridos em blocos de teste 20 PCF (p < 0,001). MIs-Ai inseridos em osso de maior densidade (40 PCF) apresentaram resistência flexural significativamente maior do que outros grupos, em deflexões de 2 mm (98,7 ± 5,1 Ncm), 3 mm (112,0 ± 3,9 Ncm) e 4 mm (120,0 ± 3,4 Ncm) (p < 0,001). A MEV evidenciou fraturas nos MIs-Ti. A EDS revelou incorporação de 18% de C e 2,06% de O nos MIs-Ai e 3,91% de C nos MIs-Ti, ambos submetidos a testes mecânicos. Conclusões: Com base nos resultados desse estudo in vitro, os MIs-Ai aparentam oferecer adequada estabilidade e maior resistência mecânica, em comparação aos MIs-Ti, quando inseridos em osso de maior densidade.

Tempo de tratamento ortodôntico com aparelhos autoligados: revisão de literatura

Introdução: Atualmente, braquetes autoligados têm sido sugeridos para reduzir o tempo de tratamento na Ortodontia. Objetivo: Dessa maneira, o presente estudo objetivou revisar a literatura acerca do tempo de tratamento com esses braquetes, em comparação com outros braquetes e tratamentos sugeridos. Revisão de literatura: Foi realizada pesquisa bibliográfica de caráter descritivo, que compreendeu o levantamento de referencial teórico na base de dados eletrônica Medline ­ PubMed. A seleção de artigos foi feita a partir dos títulos e resumos e a revisão compreendeu 4 artigos publicados na língua inglesa no período de 2019 a 2023. Conclusão: Há uma escassez de estudos clínicos envolvendo essa temática e o tratamento ortodôntico com aparelhos autoligados parece apresentar menor tempo de tratamento em comparação com aparelhos fixos tradicionais. No entanto, os estudos não mostraram diferenças estatisticamente significativas na redução desse tempo. Pode-se sugerir que mais estudos clínicos sejam conduzidos no intuito de elucidar essa questão.

Introduction: Currently, self-ligating brackets have been suggested to reduce treatment time in Orthodontics. Objective: Therefore, the present study aimed to review the literature about the treatment time with these brackets, in comparison with other brackets and suggested treatments. Literature review: Descriptive bibliographical research was carried out, which included the survey of theoretical references in the electronic database Medline ­ PubMed. The selection of articles was made based on titles and abstracts and the review comprised 4 articles published in the English language from 2019 to 2023. Conclusion: there is a shortage of clinical studies involving this topic and orthodontic treatment with self-ligating appliances seems to present shorter treatment time compared to traditional fixed appliances. However, the studies did not show statistically significant differences in reducing this time. It can be suggested that more clinical studies be conducted to elucidate this issue.

Analgesia por láser de baja potencia en pacientes con tratamiento ortodóncico / Low power laser analgesia in patients with orthodontic treatment i: en

Introducción: El dolor es el síntoma más común luego de la primera activación de la aparatología ortodóncica. El tratamiento analgésico más utilizado es el paracetamol; sin embargo, su uso inhibe la actividad de la ciclooxigenasa y la síntesis de prostaglandinas, lo que puede afectar el mecanismo del movimiento dental y el remodelado óseo. Objetivo: Evaluar la efectividad del láser de baja potencia para el alivio del dolor en pacientes con tratamiento ortodóntico. Métodos: Se realizó un estudio cuasiexperimental de intervención terapéutica, desde enero hasta diciembre de 2020, en 40 pacientes atendidos en la consulta de ortodoncia del Hospital General Docente Dr. Juan Bruno Zayas Alfonso de Santiago de Cuba, en quienes se aplicaría fuerza ortodóncica por primera vez. Estos fueron distribuidos de forma aleatoria en 2 grupos de 20 integrantes cada uno: el de estudio, tratado con láser de baja potencia, y el de control, que recibió medicación convencional (paracetamol). Para la validación estadística de la información se emplearon el porcentaje y la prueba de la t de Student para muestras independientes, con 95 % de confiabilidad. Resultados: Luego de tres sesiones terapéuticas, 90,0 % del grupo de estudio refirió no presentar dolor o sentirlo de forma leve, mientras que del grupo de control solo 10,0 % de los pacientes fue ubicado en cualquiera de las dos categorías anteriores. Existió diferencia significativa entre ambos grupos (p=0,00). Conclusiones: Se demostró que el láser, como terapia alternativa, fue más efectivo que el paracetamol.

Introduction: Pain is the most common symptom after the first activation of orthodontic appliance. The most widely used analgesic treatment is paracetamol; however, its use inhibits cyclooxygenase activity and prostaglandin synthesis, which can affect the mechanism of tooth movement and bone remodeling. Objective: To evaluate the effectiveness of low power laser for pain relief in patients with orthodontic treatment. Methods: A quasi-experimental study of therapeutic intervention was carried out, from January to December 2020, in 40 patients treated at the orthodontic clinic of Dr. Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba, in whom orthodontic force was applied for the first time. These were randomly distributed into 2 groups of 20 members each: the study group, treated with low-power laser, and the control group, that received conventional medication (paracetamol). For statistical validation of data, the percentage and the Student's t test for independent samples were used, with 95 % confidence interval. Results: After three therapeutic sessions, 90.0% of the study group reported not presenting pain or feeling it slightly, while only 10.0% of patients in control group were put in any of the two previous categories. There was a significant difference between both groups (p=0.00). Conclusions: Laser, as an alternative therapy, was shown to be more effective than paracetamol.

Alignment efficiency and three-dimensional assessment of root resorption after alignment with conventional and copper-nickel-titanium archwires: A randomized controlled trial

ABSTRACT Objective: To compare alignment efficiency and root resorption between nickel-titanium (NiTi) and copper-nickel-titanium (CuNiTi) archwires after complete alignment in mandibular anterior region. Methods: In this two-arm parallel single-blind randomized controlled trial, forty-four patients with Class I malocclusion with mandibular anterior crowding were recruited form orthodontic clinic of All India Institute of Medical Sciences (Jodhpur, India). Patients were randomly allocated into NiTi and CuNiTi groups, with a 1:1 allocation. Alignment was performed using 0.014-in, 0.016-in, 0.018-in, 0.019x0.025-in archwire sequence in the respective groups, which terminated in 0.019 x 0.025-in stainless-steel working archwire. The primary outcome was alignment efficiency, measured on study models from baseline (T0) to the first, second, third, fourth and fifth-month (T5). Secondary outcome was root resorption, measured from CBCT scans taken at T0 and T5. Mixed-factorial ANOVA was used to compare Little's Irregularity Index (LII). For assessing the proportion of patients with complete alignment at the end of each month, Kaplan-Meier survival curve was built and time to treatment completion was compared between groups using log rank test. Paired t-test was used to assess external apical root resorption (EARR) within groups, whereas independent t-test was used to evaluate LII and EARR between the groups. Results: Twenty-two patients were recruited in each group. One patient was lost to follow-up in the CuNiTi group. No statistically significant differences were observed in alignment efficiency between the groups (p>0.05). Intergroup comparison revealed that the changes in root measurement in three-dimensions were not statistically significant (p>0.05), except for mandibular right central incisor, which showed increased resorption at root apex in NiTi group (p<0.01). Conclusion: The two alignment archwires showed similar rate of alignment at all time points. Root resorption measurement did not differ between the NiTi and CuNiTi groups, except for the mandibular right central incisor, which showed more resorption in NiTi group.

RESUMO Objetivo: Comparar os fios de níquel-titânio (NiTi) e de cobre-níquel-titânio (CuNiTi) quanto à eficiência do alinhamento e quantidade de reabsorção radicular, após alinhamento completo dos dentes da região anterior inferior. Métodos: Neste estudo clínico randomizado, cego, paralelo, de dois braços, quarenta e quatro pacientes com má oclusão Classe I e apinhamento anterior inferior foram recrutados na clínica ortodôntica do All India Institute of Medical Sciences (Jodhpur, India). Os pacientes foram alocados aleatoriamente nos grupos NiTi e CuNiTi, na proporção de 1:1. O alinhamento foi realizado usando a sequência de fios 0,014", 0,016", 0,018" e 0,019" x 0,025" nos respectivos grupos, finalizando com o arco de trabalho 0,019" x 0,025" de aço inoxidável. O desfecho primário foi a eficiência do alinhamento, medida nos modelos de estudo nos tempos inicial (T0) e após um, dois, três, quatro e cinco meses (T5). O desfecho secundário foi a reabsorção radicular, medida a partir de tomografias computadorizadas realizadas em T0 e T5. ANOVA fatorial mista foi utilizada para comparar o Índice de Irregularidade de Little (IIL). Para avaliar a proporção de pacientes com alinhamento completo ao fim de cada mês, foi construída uma curva de sobrevida pelo método de Kaplan-Meier, e o tempo até o fim do tratamento foi comparado entre os grupos por meio do teste log-rank. Um teste t pareado foi utilizado para avaliar a reabsorção radicular apical externa (RRAE) dentro dos grupos, enquanto um teste t independente foi utilizado para avaliar o IIL e a RRAE entre os grupos. Resultados: Vinte e dois pacientes foram recrutados em cada grupo. Um paciente perdeu o acompanhamento no grupo CuNiTi. Não foram observadas diferenças estatisticamente significativas entre os grupos quanto à eficiência do alinhamento (p>0,05). A comparação intergrupos revelou que as alterações na RRAE medida em três dimensões não foram estatisticamente significativas (p>0,05), exceto para o incisivo central inferior direito, que apresentou aumento da RRAE no grupo NiTi (p<0,01). Conclusão: Os dois tipos de fios de alinhamento apresentaram taxa de alinhamento semelhante em todos os momentos. A medida da reabsorção radicular não diferiu entre o grupo NiTi e CuNiTi, exceto para o incisivo central inferior direito, que apresentou maior reabsorção no grupo NiTi.