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This study aimed to evaluate the effects of the estrogen depression during orthodontic tooth movement on alveolar bone microarchitecture and periodontal ligament. Female Wistar rats were divided into two groups, one consisting of non-ovariectomized animals subjected to orthodontic tooth movement, and one comprising ovariectomized animals subjected to orthodontic tooth movement. Micro-CT assessment of bone volume to total volume (BV/TV), total porosity, trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) in the alveolar bone of the orthodontically moved tooth was performed. Histomorphometric analyses were made in the periodontal ligament, and immunoexpression of RANK, RANKL, OPG, and TUNEL were quantified. Orthodontic tooth movement in the group of ovariectomized rats was faster than in non-ovariectomized animals. The alveolar bone area showed lower values of BV/TV and trabecular thickness, and higher bone porosity and trabeculae numbers in the ovariectomized rats. Histological analyses in the ovariectomized group revealed an increase in collagen fibers in the periodontal ligament. The apoptotic cell counts in the periodontal ligament were higher in the group of ovariectomized rats than in the sham-operated rats. Ovariectomy resulted in an increase in tooth movement and alteration of the alveolar bone microstructure in the first 7 day of orthodontic tooth movement, and in the presence of apoptotic cells in the periodontal ligament.

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BACKGROUND: There are several publications that show the efficacy of surgical interventions in accelerating the rate of tooth movement in orthodontics. Consequently, possible adverse effects must also be evaluated. OBJECTIVES: The aim of the present study was to compare the perception of pain and root resorption between orthodontic treatment with a surgical acceleration intervention vs. conventional orthodontic treatment. MATERIAL AND METHODS: An electronic search was conducted in the MEDLINE, Scopus, Web of Science (WoS), ScienceDirect, Cochrane Library, and Virtual Health Library (VHL) databases up to September 12, 2022. Randomized or non-randomized, controlled, parallel-arm or split-mouth clinical trials were included. Fixed-and random-effects meta-analyses were performed with regard to heterogeneity. The risk of bias (RoB) was assessed using the RoB 2.0 and ROBINS-I tools. RESULTS: A total of 1,395 articles were initially retrieved, 40 studies were finally included in the review and 15 studies were eligible for quantitative analysis. The meta-analysis showed a significant difference in pain perception between acceleration surgery vs. conventional orthodontics at 24 h (p = 0.040); however, this difference was not significant at 7 days (p = 0.080). Overall, the patients who underwent any acceleration procedure presented significantly less resorption as compared to those who were applied conventional treatment (p < 0.001). A similar significant difference was found in retraction movements (p < 0.001) and alignment movements (p = 0.030). CONCLUSIONS: In the first 24 h, surgical interventions for the acceleration of tooth movement produce a greater perception of pain as compared to conventional orthodontic treatment, but the perception is similar after 7 days. Acceleration surgery results in less root resorption - in alignment movements, and especially in retraction movements.

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Objective Isotretinoin, also known as 13-cis-retinoic acid, is an isomer of tretinoin, the oxidized form of Vitamin A. Orthodontic tooth movement (OTM) is the result of a cascade of inflammatory responses stimulated by a physical element that is the force generated by orthodontic appliances. Isotretinoin is mainly used among adolescents and young adults, and coincidentally it is this age group that also undergoes orthodontic treatment. Materials and Methods Fifty-five animals were used, and they were randomly divided into 11 groups, containing 5 animals in each group. Group 1: Control; Group 2: OTM for 7 days; Group 3: OTM for 14 days; Group 4: Treated with isotretinoin for 14 days with a dosage of 7.5 mg/kg/day; Group 5: Treated with isotretinoin for 14 days with a dosage of 1.0 mg/kg/day; Group 6: Treated with isotretinoin for 21 days with a dosage of 7.5 mg/kg/day; Group 7: Treated with isotretinoin for 21 days with a dosage of 1.0 mg/kg/day; Group 8: Treated with isotretinoin for 14 days with a dosage of 7.5 mg/kg/day and undergoing OTM for 7 days; Group 9: Treated with isotretinoin for 14 days with a dosage of 1.0 mg/kg/day and undergoing OTM for 7 days; Group 10: Treated with isotretinoin for 21 days with a dosage of 7.5 mg/kg/day and undergoing OTM for 14 days; Group 11: Treated with isotretinoin for 21 days with a dosage of 1.0 mg/kg/day and undergoing OTM for 14 days. In Groups 8, 9, 10 and 11, the animals were treated with isotretinoin for 7 days before OTM and maintained during the movement period in the respective groups. Results There was a significant difference in microtomographic parameters, including Trabecular Volume (BV/TV), Trabecular Thickness (Tb.Th), Number of Trabeculae (Tb.N), and Trabecular Separation (Tb.Sp), between the groups. The group that received orthodontic force in conjunction with isotretinoin treatment at a dosage of 7.5 mg/kg/day exhibited lower tooth displacement over a period of 21 days and 14 days. Conclusion Isotretinoin caused a reduction in tooth displacement during OTM when administered at a dose of 7.5 mg/kg/day and isotretinoin did change the microtomographic parameters of treated animals.

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PURPOSE: This study aimed to verify whether there is a difference in biomarker levels in the gingival crevicular fluid between premenopausal and postmenopausal women undergoing orthodontic treatment. METHODS: As eligibility criteria, prospective or retrospective observational studies evaluating women undergoing orthodontic treatment (P), comparing postmenopausal (E) and premenopausal (C) women, and analyzing differences in gingival crevicular fluid biomarkers (O) were included. An electronic search was conducted in seven databases (PubMed, Scopus, Web of Science, LILACS, The Cochrane Library, Embase, and EBSCO: Dentistry & Oral Science) and one grey literature source (Google Scholar). All databases were searched from September 2022 to March 2023. After duplicate exclusion and data extraction, the Newcastle-Ottawa scale was applied to assess the quality and risk of bias, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool was used to verify the certainty of evidence. RESULTS: Three case-control studies that analyzed receptor activator of nuclear factor kappa­B ligand (RANKL), osteopontin (OPN), and interleukin (IL)-17A levels were included. One study reported a significant difference for RANKL and another for OPN levels. A third study reported that there was a higher expression of IL17­A in the postmenopausal group. However, the small number of articles limits our systematic review. The heterogeneity and imprecision in the study results cast doubt on the findings' internal validity. CONCLUSION: The studies reported alterations in biomarker levels but differed in their conclusions. Therefore, further studies must include other types of bone and inflammatory biomarkers in female patients who are pre- or postmenopausal and undergoing orthodontic treatment. REGISTRATION: The review was registered at the Open Science Framework ( https://doi.org/10.17605/OSF.IO/Q9YZ8 ).

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Previous studies have suggested a role of phosphatidylinositol-3-kinase gamma (PI3Kγ) in bone remodeling, but the mechanism remains undefined. Here, we explored the contribution of PI3Kγ in the resorption of maxillary bone and dental roots using models of orthodontic tooth movement (OTM), orthodontic-induced inflammatory root resorption, and rapid maxillary expansion (RME). PI3Kγ-deficient mice (PI3Kγ-/- ), mice with loss of PI3Kγ kinase activity (PI3KγKD/KD ) and C57BL/6 mice treated with a PI3Kγ inhibitor (AS605240) and respective controls were used. The maxillary bones of PI3Kγ-/- , PI3KγKD/KD , and C57BL/6 mice treated with AS605240 showed an improvement of bone quality compared to their controls, resulting in reduction of the OTM and RME in all experimental groups. PI3Kγ-/- mice exhibited increased root volume and decreased odontoclasts counts. Consistently, the pharmacological blockade or genetic deletion of PI3K resulted in increased numbers of osteoblasts and reduction in osteoclasts during OTM. There was an augmented expression of Runt-related transcription factor 2 (Runx2) and alkaline phosphatase (Alp), a reduction of interleukin-6 (Il-6), as well as a lack of responsiveness of receptor activator of nuclear factor kappa-Β (Rank) in PI3Kγ-/- and PI3KγKD/KD mice compared to control mice. The maxillary bones of PI3Kγ-/- animals showed reduced p-Akt expression. In vitro, bone marrow cells treated with AS605240 and cells from PI3Kγ-/- mice exhibited significant augment of osteoblast mineralization and less osteoclast differentiation. The PI3Kγ/Akt axis is pivotal for bone remodeling by providing negative and positive signals for the differentiation of osteoclasts and osteoblasts, respectively.

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ABSTRACT Objective: This study was designed to analyze and compare the cusp and apex movements of the maxillary canines and first molars during canine retraction in the first step of extraction space closure, and to evaluate if these teeth follow a curvilinear (acceleration and/or deceleration) movement rate. Material and Methods: Twenty-five patients (23.3 ± 5.1 years of age) were enrolled. The retraction of the maxillary canines was accomplished using nickel-titanium closed coil springs (100gf) on 0.020-in stainless steel archwire. Oblique cephalograms were traced and superimposed on the anatomic best fit of the maxilla (before the retraction [T0], and after one month [T1], three [T3], five [T5] and seven [T7] months). Statistics was based in a normally distributed data. Multilevel procedures were used to derive polynomials for each of the measurements. Student's t-test and one-way repeated measures ANOVA were conducted. The level of significance of 5% was adopted. Results: Canine cusps and apexes did not follow a quadratic curve regarding horizontal movement (neither accelerate nor decelerate). Canine and molar cusps showed more horizontal movement than apexes (4.80 mm vs. 2.78 mm, and 2.64 mm vs. 2.17 mm, respectively). Conclusions: Canine did not accelerate or decelerate overtime horizontally; the cusps and apexes of the canines and molars showed more horizontal movement and larger rate at the beginning of canine retraction, followed by significantly smaller and constant movement rate after the first month.

RESUMO Objetivo: O objetivo deste estudo foi analisar a movimentação das cúspides e dos ápices de caninos e primeiros molares superiores durante a retração de caninos na primeira fase do fechamento do espaço pós-extração, e avaliar se esses dentes apresentam mudança na taxa de movimentação (aceleração e/ou desaceleração). Material e Métodos: Vinte e cinco pacientes (idade = 23,3 ± 5,1 anos) foram incluídos. A retração dos caninos superiores foi realizada com molas helicoidais fechadas de níquel-titânio (100gf) em arco 0,020" de aço inoxidável. Foram feitos traçados cefalométricos de telerradiografias oblíquas e sobrepostos ao melhor ajuste anatômico da maxila (antes da retração [T0]; após um mês [T1], três meses [T3], cinco meses [T5] e sete meses [T7]). A estatística foi baseada em dados com distribuição normal. Procedimentos multiníveis foram usados para derivar polinômios para cada uma das medidas. Teste t de Student e ANOVA de uma via para medidas repetidas foram realizados, adotando-se um nível de significância de 5%. Resultados: As cúspides e os ápices dos caninos não seguiram uma curva quadrática em relação ao movimento horizontal (sem aceleração ou desaceleração). As cúspides dos caninos e molares apresentaram mais movimento horizontal do que os ápices (4,80 mm vs. 2,78 mm e 2,64 mm vs. 2,17mm, respectivamente). Conclusões: A movimentação horizontal dos caninos não acelerou ou desacelerou ao longo do tempo; as cúspides e os ápices dos caninos e molares apresentaram maior movimento horizontal e maior taxa de movimentação no início da retração dos caninos, seguida por uma taxa de movimentação significativamente menor e constante após o primeiro mês.

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During orthodontic tooth movement (OTM), there is the release of cytokines in the gingival crevicular fluid (GCF) that are supposed to participate in the bone remodeling. This systematic review aimed at assessing the effects of photobiomodulation (PBM) on the levels of these cytokines during OTM. This systematic review according to Cochrane Collaboration guidelines aimed to answer the clinical question following the PICOS strategy. The broad search in the literature was performed before 05 April, 2021 in six electronic databases (Pubmed, Web of Science, Scopus, Embase, Cochrane, Biblioteca Virtual de Saúde) and supplemented by the grey literature. The risk of bias of randomized and non-randomized clinical trials was evaluated by two tools: RoB 2 and ROBINS-I. Mean and standard deviation of cytokine levels was extracted to meta-analysis, and the GRADE system was applied to assess the quality of the evidence. Nine studies were included in this review. Low-level laser therapy (LLLT) was the photobiomodulation type used in most of the studies (n = 8). The wavelengths used varied from 618 to 980 nm and also differed concerning the light emission pattern. LLLT increased the levels of IL-1ß, IL-8, OPN, and PGE2, but not TNF-α1, TGF-ß1. The levels of IL6, RANKL, and OPG presented conflicting results. LLLT was statistically associated with an increase of IL-1ß levels (standard mean difference [SMD] = 1.99; 95% confidence interval = 0.66 to 3.33; p < 0.001) with low certainty of evidence. LLLT may increase the levels of IL-1ß and other cytokines; however, the results should be interpreted with caution due to protocol variations between studies, and the few studies added in the meta-analysis.

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ABSTRACT Objective: This article aims to discuss the multidisciplinary approach required in the treatment of cases of impaction and ankylosis of permanent teeth, associated with a history of trauma, considering the psychological state of the child and family when faced with a traumatic case of bullying, by reporting the complex treatment of a central incisor needing to be orthodontically moved across the midline. Conclusion: This clinical case was a major challenge, which included complex multidisciplinary procedures. Results and stability after 26 months of retention indicated successful orthodontic space closure of two maxillary teeth, without the use of implants or prostheses, in an adolescent patient who had a history of dental trauma, alveolar bone loss, and an uncertain initial prognosis.

RESUMO Objetivo: O presente artigo tem como objetivo discutir a abordagem multidisciplinar necessária no tratamento de casos de impacção e anquilose de dentes permanentes, associados a histórico de trauma, considerando o estado psicológico da criança e da família diante de situações traumáticas de bullying, por meio do relato do tratamento complexo de um incisivo central que precisava ser movido ortodonticamente através da linha média. Conclusão: Esse caso foi um grande desafio, que incluiu procedimentos multidisciplinares complexos. Os resultados e a estabilidade após 26 meses de contenção indicaram fechamento ortodôntico bem-sucedido do espaço de dois dentes superiores, sem o uso de implantes ou próteses, em uma paciente adolescente que apresentava histórico de trauma dentário, perda de osso alveolar e prognóstico inicial incerto.

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ABSTRACT Introduction: Micro-osteoperforation is a minimally invasive technique that has been used to accelerate orthodontic tooth movement and reduce treatment duration. However, literature presents conflicting reports about this technique. Objective: To evaluate the effectiveness of micro-osteoperforations on the rate of canine retraction and expression of biomarkers in gingival crevicular fluid (GCF). Methods: This was a randomized clinical trial with split-mouth study design. Thirty adult subjects with age above 18 years (20.32 ± 1.96) who required fixed orthodontic treatment and extraction of maxillary first premolars were enrolled and randomly allocated to either the experimental or control group. Randomization was performed by block randomization method, with a 1:1 allocation ratio. The experimental group received three micro-ostoperforations (MOPs) distal to maxillary canine, using the Lance pilot drill. The retraction of maxillary canine was performed with NiTi coil-spring (150g) in both experimental and control groups. The primary outcome was the evaluation of canine retraction rate, measured on study models from the baseline to 16 weeks of canine retraction. Secondary outcomes were the estimation of alkaline and acid phosphates activity in GCF at 0, 1, 2, 3, and 4 weeks. Results: There was a statistically significant difference in the rate of canine retraction only after the first 4 weeks. Subsequently there was no statistically significant difference from the eighth to the sixteenth weeks between MOPs and control group. There was a statistically significant difference in alkaline and acid phosphates activity in GCF between MOPs and control groups during the initial 4 weeks of canine retraction. Conclusion: Micro-ostoperforation increased the rate of tooth movement only for the first 4 weeks; thereafter, no effect was observed on the rate of canine retraction during 8, 12 and 16 weeks. A marked increase in biomarker activity in the first month was observed.

RESUMO Introdução: As micro-osteoperfurações (MOPs) são uma técnica minimamente invasiva que tem sido utilizada para acelerar a movimentação dentária ortodôntica e reduzir o tempo de tratamento. No entanto, existem relatos conflitantes sobre o uso dessa técnica. Objetivo: Avaliar a eficácia das MOPs em acelerar a taxa do movimento de retração de caninos e na expressão de biomarcadores no fluido crevicular gengival (FCG). Métodos: Esse foi um ensaio clínico randomizado com desenho de estudo do tipo boca dividida. Trinta indivíduos adultos com idade acima de 18 anos (20,32 ± 1,96 anos) que necessitavam de tratamento ortodôntico fixo e extração de primeiros pré-molares superiores foram incluídos e aleatoriamente alocados para o grupo experimental ou grupo controle. A randomização foi realizada pelo método de randomização em bloco, com proporção de alocação de 1:1. O grupo experimental recebeu três MOPs distais ao canino superior, utilizando uma broca piloto em formato de lança. A retração do canino superior foi realizada com mola helicoidal de NiTi (150g) nos dois grupos, experimental e controle. O desfecho primário foi a avaliação da taxa de retração dos caninos, medida em modelos de estudo do início da retração até 16 semanas depois. O desfecho secundário foi a estimativa da atividade da fosfatase alcalina e ácida no FCG após 0, 1, 2, 3 e 4 semanas. Resultados: Houve uma diferença estatisticamente significativa na taxa de retração dos caninos somente após as quatro primeiras semanas. Após isso, não houve diferença estatisticamente significativa entre os grupos experimental e controle entre a oitava e a décima sexta semanas. Houve uma diferença estatisticamente significativa na atividade da fosfatase alcaline e ácida no FCG entre os grupos experimental e controle durante as quatro primeiras semanas de retração dos caninos. Conclusão: As micro-osteoperfurações aumentaram a taxa de movimentação dentária apenas nas primeiras quatro semanas; depois disso, nenhum efeito foi observado na taxa de retração dos caninos após 8, 12 e 16 semanas. Houve aumento considerável na atividade do biomarcador no primeiro mês.

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ABSTRACT Introduction: The literature reports the association of external root resorption (ERR) with orthodontic movement. In cases of premolars extractions, orthodontic movement of anterior teeth is usually quite expressive, which are precisely the most susceptible teeth to suffer from ERR. Objective: The aim of this study was to assess the root morphology of maxillary canines and incisors in patients submitted to four premolar extraction and orthodontic retraction of the anterior teeth, by means of 3D surface models superimposition and mapping. Methods: The sample consisted of six adult patients, five female and one male, with a mean age of 23.5 ± 6.5 years, who underwent orthodontic treatment. All patients presented bimaxillary dental protrusion, with indication of maxillary and mandibular first premolar extractions, followed by the retraction of anterior teeth and space closure. Cone beam CT scans were performed before the beginning of the treatment (T0) and right after space closure (T1). 3D models were built at both times and superimposed to identify the root changes for the given period. Results: All average differences were close to zero and, even when evaluating the extreme values, the observed changes were always smaller than the accuracy of the CBCT. Conclusion: A mild resorption trend was observed, although it was not clinically significant, with values lower than the tomography accuracy.

RESUMO Introdução: A literatura relata a associação de reabsorção radicular externa (RRE) com a movimentação ortodôntica. Nos casos de extrações de pré-molares, a movimentação ortodôntica costuma ser bastante expressiva nos dentes anteriores, que são justamente os dentes mais suscetíveis à RRE. Objetivo: O objetivo do presente estudo foi avaliar a morfologia radicular de caninos e incisivos superiores em pacientes submetidos à extração de quatro pré-molares e retração ortodôntica dos dentes anteriores, por meio da sobreposição e mapeamento de modelos 3D. Métodos: A amostra foi composta por seis pacientes adultos, cinco do sexo feminino e um do masculino, com média de idade de 23,5 ± 6,5 anos, submetidos a tratamento ortodôntico. Todos os pacientes apresentavam biprotrusão dentária, com indicação de extração dos primeiros pré-molares superior e inferior, seguida de retração dos dentes anteriores e fechamento do espaço. A tomografia computadorizada de feixe cônico (TCFC) foi realizada antes do início do tratamento (T0) e logo após o fechamento de espaços (T1). Modelos 3D foram construídos em ambos os momentos e sobrepostos para identificar as mudanças nas raízes dentárias no período determinado. Resultados: Todas as médias das diferenças foram próximas de zero e, mesmo avaliando os valores extremos, as mudanças observadas foram sempre menores que a sensibilidade da TCFC. Conclusão: Observou-se tendência de leve reabsorção, embora não clinicamente significativa, com valores inferiores à sensibilidade tomográfica.

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Background: In recentyears, there has been an increasing interest in finding a noninvasive method to induce the accelerationofdentalmovement,methodssuchaslowintensityvibrations,pulsedelectromagneticfields,andlow-level laser therapy (LLLT). There have been multiple studies on the efficacy of LLLT in animal models, in vitro and in patients without conclusiveresults. Objective: Evaluate the state of the art on the use of LLLT to increase the rate of the orthodontic tooth movement to create a concise reference guide of the different laser and protocols available. Materials and Methods: The authors searched electronic databases (MedLine, Scopus and Semantic Scholar) for articles that evaluated the effectsoflow-leverlasertherapyontheorthodontictoothmovement.Screeningwasperformedatthetitle/abstract and full-text level. Data extraction and quality assessment were performed by two reviewers independently. The reference lists of relevant studies were also screened for further relevantliterature. Results: We found conflicting information as to the efficacy of LLLT to accelerate the orthodontic tooth movement (OTM). There is no consensus in the way the irradiation should be performed. Conclusions: The lack of a standardized irradiation protocol makes it hard to compare conflicting results, even in cases where the laser have the same technical specifications.

Antecedentes: En los últimos años, ha habido un interés creciente en encontrar un método no invasivo para inducir la aceleración del movimiento dental, métodos como vibraciones de baja intensidad, campos electromagnéticos pulsados y terapia con láser de bajo nivel(LLLT). Se han realizado múltiples estudios sobre la eficacia de la LLLT en modelos animales, in vitro y en pacientes sin resultados concluyentes. Objetivo: Evaluar el estado del arte en el uso de LLLT para aumentar la velocidad del movimiento dental ortodóncico para crear una guía de referencia concisa de los diferentes láser y protocolos disponibles. Materiales y métodos: Los autores buscaron en bases de datos electrónicas (MedLine, Scopus y Semantic Scholar) artículos que evaluaran los efectos de la terapia con láser de baja intensidad sobre el movimiento dental ortodóncico. La selección se realizó a nivel de título / resumen y texto completo. Dos revisores realizaron de forma independiente la extracción de datos y la evaluación de la calidad. También se examinaron las listas de referencias de estudios relevantes para obtener más literatura significativa. Resultados:EncontramosinformacióncontradictoriaencuantoalaeficaciadelaLLLTparaacelerarel movimiento dental ortodóncico (OTM).No hay consenso sobre la forma en que se debe realizar lairradiación. Conclusiones: La falta de un protocolo de irradiación estandarizado dificulta la comparación de resultados, incluso en los casos en que el láser tiene las mismas especificaciones técnicas.

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AIM: We aimed to evaluate the correlation between the polymorphism of the interleukin 1-Beta (IL1-ß, +3954 C>T) and tooth movement, in a group of Colombian patients undergoing surgically accelerated orthodontic tooth movement. METHODS: The study was nested to a controlled clinical trial. Blood samples were taken from 11 women and 29 healthy Colombian male volunteers between 18 and 40 years old, after 1 year of starting orthodontic treatment. The patients presented malocclusion class I, with grade II or III. To detect the genetic polymorphism of the nucleotide +3954 C to T in the IL-1ß gene, we used a real-time PCR assay. RESULTS: Eleven individuals presented the allele 2 (T) heterozygous with the allele 1 (T/C) and 19 individuals were homozygous for the allele 1 (C/C). When analyzing the presence of the SNP, no significant differences were found in any of the variables. The best treatment was reflected in Group 3 (selective upper and lower alveolar decortication and 3D collagen matrix) and Group 4 (only selective alveolar decortication in the upper arch, with 3D collagen matrix), with 27% and 35% more speed respectively than in the control group. CONCLUSIONS: Our analyses indicated that a reduction in the total treatment time can be mostly potentiated by using decortication and collagen matrices and not for the presence of the allele 2 in the IL-1ß. Nevertheless, it is important that further studies investigate if the polymorphism could be associated with the speed of tooth movement and analyze the baseline protein levels.

OBJETIVO: Evaluar la correlación entre el polimorfismo de la interleucina 1-Beta (IL1-ß, +3954 C> T) y el movimiento de los dientes, en un grupo de pacientes colombianos sometidos a un movimiento dental ortodóncico acelerado quirúrgicamente. MÉTODOS: Este fue un estudio secundario derivado de un ensayo clínico aleatorio controlado. Se tomaron muestras de sangre de 11 mujeres y 29 voluntarios varones colombianos sanos entre 18 y 40 años, después de 1 año de comenzar el tratamiento de ortodoncia. Los pacientes presentaron maloclusión clase I, con grado II o III. Para detectar el polimorfismo genético del nucleótido +3954 C a T en el gen IL-1ß, se usó un ensayo de PCR en tiempo real. RESULTADOS: 11 individuos presentaron el alelo 2 (T) heterocigoto con el alelo 1 (T / C) y 19 individuos fueron homocigotos para el alelo 1 (C / C). Al analizar la presencia del SNP, no se encontraron diferencias significativas en ninguna de las variables. El mejor tratamiento se reflejó en el Grupo 3 (decorticación alveolar superior e inferior selectiva y matriz de colágeno 3D) y el Grupo 4 (solo decorticación alveolar selectiva en el arco superior, con matriz de colágeno 3D), con un 27% y un 35% más de velocidad, respectivamente, que en el grupo de control. CONCLUSIONES: Los análisis indicaron que una reducción en el tiempo total de tratamiento puede potenciarse principalmente mediante el uso de decorticación y matrices de colágeno y no por la presencia del alelo 2 en la IL-1ß. Sin embargo, es importante que otros estudios investiguen si el polimorfismo podría estar asociado con la velocidad del movimiento de los dientes y analizar los niveles de proteína de referencia.

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Abstract Aim: We aimed to evaluate the correlation between the polymorphism of the interleukin 1-Beta (IL1-β, +3954 C>T) and tooth movement, in a group of Colombian patients undergoing surgically accelerated orthodontic tooth movement. Methods: The study was nested to a controlled clinical trial. Blood samples were taken from 11 women and 29 healthy Colombian male volunteers between 18 and 40 years old, after 1 year of starting orthodontic treatment. The patients presented malocclusion class I, with grade II or III. To detect the genetic polymorphism of the nucleotide +3954 C to T in the IL-1β gene, we used a real-time PCR assay. Results: Eleven individuals presented the allele 2 (T) heterozygous with the allele 1 (T/C) and 19 individuals were homozygous for the allele 1 (C/C). When analyzing the presence of the SNP, no significant differences were found in any of the variables. The best treatment was reflected in Group 3 (selective upper and lower alveolar decortication and 3D collagen matrix) and Group 4 (only selective alveolar decortication in the upper arch, with 3D collagen matrix), with 27% and 35% more speed respectively than in the control group. Conclusions: Our analyses indicated that a reduction in the total treatment time can be mostly potentiated by using decortication and collagen matrices and not for the presence of the allele 2 in the IL-1β. Nevertheless, it is important that further studies investigate if the polymorphism could be associated with the speed of tooth movement and analyze the baseline protein levels.

Resumen Objetivo: Evaluar la correlación entre el polimorfismo de la interleucina 1-Beta (IL1-β, +3954 C> T) y el movimiento de los dientes, en un grupo de pacientes colombianos sometidos a un movimiento dental ortodóncico acelerado quirúrgicamente. Métodos: Este fue un estudio secundario derivado de un ensayo clínico aleatorio controlado. Se tomaron muestras de sangre de 11 mujeres y 29 voluntarios varones colombianos sanos entre 18 y 40 años, después de 1 año de comenzar el tratamiento de ortodoncia. Los pacientes presentaron maloclusión clase I, con grado II o III. Para detectar el polimorfismo genético del nucleótido +3954 C a T en el gen IL-1β, se usó un ensayo de PCR en tiempo real. Resultados: 11 individuos presentaron el alelo 2 (T) heterocigoto con el alelo 1 (T / C) y 19 individuos fueron homocigotos para el alelo 1 (C / C). Al analizar la presencia del SNP, no se encontraron diferencias significativas en ninguna de las variables. El mejor tratamiento se reflejó en el Grupo 3 (decorticación alveolar superior e inferior selectiva y matriz de colágeno 3D) y el Grupo 4 (solo decorticación alveolar selectiva en el arco superior, con matriz de colágeno 3D), con un 27% y un 35% más de velocidad, respectivamente, que en el grupo de control. Conclusiones: Los análisis indicaron que una reducción en el tiempo total de tratamiento puede potenciarse principalmente mediante el uso de decorticación y matrices de colágeno y no por la presencia del alelo 2 en la IL-1β. Sin embargo, es importante que otros estudios investiguen si el polimorfismo podría estar asociado con la velocidad del movimiento de los dientes y analizar los niveles de proteína de referencia.

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OBJECTIVES: This study evaluated, in experimental model, the inflammatory alterations in gingival tissue and alveolar bone during the orthodontic tooth movement (OTM) in diabetes mellitus (D) and periodontitis (P). SETTING AND SAMPLE POPULATION: Forty male Wistar rats, 90 days old and weighing 300 g. MATERIALS AND METHODS: The sample was divided into four groups (n = 10). OTM: orthodontic movement (10 days, 0.4 N force); P + OTM: periodontitis (ligature-induced periodontitis, 3-0 silk suture thread) and orthodontic movement; D + OTM: diabetes (Alloxan-induced diabetes, 150 mg/kg) and orthodontic movement; and D + P + OTM: diabetes, periodontitis and orthodontic movement. Tooth displacement was measured; fibroblast, inflammatory cells, osteoclast and blood vessels were quantified by histomorphometric analysis. Inflammatory markers, interleukin-6 (IL-6) and tumour necrosis factor (TNF-α) were quantified by ELISA (Enzyme-Linked Immunosorbent Assay) in gingival tissue. The fibroblastic growth factor (bFGF), transforming growth factor (TGF-ß1) and the vascular endothelial growth factor (VEGF) were measured via Western blotting in the alveolar bone. The results were analysed by ANOVA and Tukey's test at a 5% significance level. RESULTS: The quantification of inflammatory cells and the expression of IL-6, TNF-α, TGF-ß1 and bFGF were increased in diabetes and periodontitis. However, the number of fibroblasts and blood vessels and the percentage of birefringent collagen fibres were higher in healthy animals. There was greater tooth displacement in the OTM group. CONCLUSION: Diabetes Mellitus modifies the inflammatory response. The increased expression of inflammatory markers IL-6, TNF-α and TGF-ß1 in diabetic animals impairs neovasculogenesis and tissue reorganization during orthodontic tooth movement, which may be aggravated by periodontitis.

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Leveling the curve of Spee is a commonly-used strategy to correct deep bites. Although several techniques have been proposed to intrude mandibular incisors (MI), flaring of these teeth is often observed and in many instances undesired. A three-dimensional (3D) finite element model (FEM) was used to locate the ideal point of force application (PFA) to achieve pure MI intrusion with the three-piece arches' technique. It comprised (1) a 0.021 × 0.025 in. stainless steel (SS) wire that passively filled the slots of the canine and premolar brackets and the first and second molar tubes, bilaterally; (2) a 0.0215 × 0.0275 in. SS intrusion base arch (IBA) inserted into the MI brackets, that presented a step down distal to the lateral incisors brackets and a posterior extension arm; (3) titanium-molybdenum tip-back springs designed to apply the intrusion force, fitted inside the first molar gingival tube. Four PFA on the IBA were simulated (FEM 1, 2, 3, and 4). FEM 3 resulted in pure MI and was considered the ideal PFA. FEM1 and 2 showed intrusion and buccal crown flaring of the MI, whereas FEM4 resulted in intrusion and lingual crown flaring of those teeth. Clinicians may consider three-piece arch mechanics to achieve pure MI intrusion. However, they must be aware that when force was applied anteriorly or posteriorly to the ideal PFA, the incisors would incline labially or lingually, respectively.

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Abstract The present study aimed to analyze the effect of LED phototherapy on the presence of hyalinization and root resorption during orthodontic tooth movement (OTM) in rats and to measure the amount of tooth movement. Eighty rats were allocated into two groups: LED and control (CON), where the LED rats were irradiated with infrared LED (850 nm, 30 mW) for 5 min during the first five days of OTM and where controls were not irradiated. Both groups were subdivided into four subgroups (n=10) according to the date of euthanasia (4, 7, 14 and 21 days). Five out of ten LED21 and five of ten CON21 rats were submitted to micro-computed tomography (μCT); μCT scans were taken on days 0, 7, 14 and 21. For histological study, maxillae were processed to light microscopy using Hematoxylin-Eosin (HE) and Tartrate-Resistant Acid Phosphatase (TRAP) histochemistry. The amount of tooth movement did not differ between LED and CON. Hyalinization was observed at the pressure areas in both groups, and it did not show a statistically significant difference between the groups. Root resorption was also observed in both groups after 7 days and it did not represent any differences between the two groups. LED phototherapy was not able to increase the amount of OTM. Similar characteristics of hyalinization and root resorption were observed in both groups.

Resumo O presente estudo tem como objetivo analisar o efeito da fototerapia LED na presença da hialinização e reabsorção radicular durante o movimento dentário ortodôntico (MDO) em ratos, e a mensuração da quantidade de movimento dentário. Oitenta ratos foram alocados em dois grupos: LED e Controle (CON), os ratos foram irradiados com um LED infravermelho (850nm, 30mW) por 5 minutos durante os cinco primeiros dias da MDO; e o grupo controle não foi irradiado. Ambos os grupos foram subdivididos em 4 subgrupos (n=10) de acordo com a data da eutanásia (4, 7, 14 e 21 dias). Cinco dos dez ratos LED21 e cinco dos dez ratos CON21foram submetidos a microtomografia computadorizada (μCT); As μCT foram realizadas nos dias 0, 7, 14 e 21. Para o estudo histológico, as maxilas foram processadas para microscopia de luz, usando hematoxilina-eosina (HE) e Fosfatase ácido Tartrate-Resistente (TRAP) para histoquímica. A quantidade de movimento dentário não diferiu entre o LED e o CON. A hialinização foi observada nas áreas de pressão em ambos os grupos e não mostrou diferença estatisticamente significante. Reabsorção radicular também foi observada em ambos os grupos depois de 7 dias e não houve diferença entre os grupos. A fototerapia LED não aumentou a quantidade de MDO. Características similares de hialinização e reabsorção radicular foram observadas em ambos os grupos

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Introdução: Considerando que a cafeína aumenta o metabolismo, muito se tem questionado se os termogênicos à base dessa substância apresentariam também alguma influência sob a taxa de movimentação ortodôntica e comportamento de roedores. Objetivo: Avaliar o efeito de duas marcas comerciais de termogênicos sobre o comportamento, o metabolismo e a movimentação ortodôntica em ratos. Metodologia: Tratou-se de um estudo experimental, in vivo, randomizado, com base descritiva e inferencial. A amostra foi constituída de 19 ratos machos Wistar (Ratus norvegicus albinus) saudáveis, entre 7 e 12 semanas de idade, os quais foram submetidos a movimentação dentária ortodôntica contínua dos primeiros permanentes molares superiores, do lado esquerdo, durante o período de 21 dias. Os ratos foram divididos aleatoriamente em 3 grupos: Grupo controle (GC) - Ratos submetidos apenas à movimentação ortodôntica e à ingestão diária de água (n=7); Grupo experimental Termogênico C4 (GT1) - Ratos submetidos à movimentação ortodôntica e à dose diária de termogênico C4 (n=8) e Grupo experimental Termogênico PRE-HD (GT2) - Ratos submetidos à movimentação ortodôntica e à dose diária de termogênico PRE-HD (n=4). A análise de movimentação ortodôntica foi feita obtendo-se a diferença da distância (em mm) da distal do 1˚ molar superior esquerdo à mesial do 2˚ molar superior do mesmo lado, medida realizada na região cervical com o auxílio de um compasso de ponta seca; a análise sistêmica foi realizada por meio de testes bioquímicos e do leucograma e o estudo comportamental através do teste de campo aberto. Resultados: Não houve diferença estatisticamente significativa entre os grupos GT1, GT2 e GC quanto à quantidade de movimentação ortodôntica (p>0,005). Com relação ao teste de campo aberto, houve diferença estatisticamente significativa (p <0,005) entre os grupos para as variáveis: movimentos ambulatórios, movimentos em pé, quantidade de pulos, distância percorrida, velocidade da distância percorrida e movimentos realizados no centro e nas bordas. E no tocante aos efeitos sistêmicos, o leucograma e os testes bioquímicos realizados não exibiram resultados significativos. Conclusão: O uso de termogênicos não exerce influência sobre a taxa de movimentação ortodôntica em ratos e não produz alterações sistêmicas relevantes, no entanto, é capaz de afetar vários aspectos do comportamento desses animais (AU).

Introduction: Considering that caffeine increases metabolism, much has been questioned whether thermogenics based on this substance would also have some influence on the rate of orthodontic movement and rodent behavior. Objective: To evaluate the effect of two thermogenic brands on behavior, metabolism and orthodontic movement in rats. Methodology: This was an experimental, in vivo, randomized study, with descriptive and inferential basis. The sample consisted of 19 healthy male Wistar rats (Ratus norvegicus albinus) between 7 and 12 weeks of age, which were submitted to continuous orthodontic movement of the first permanent maxillary molars on the left side during the 21 day period. The rats were randomly divided into 3 groups: Control group (CG) - Rats submitted only to orthodontic movement and daily water intake (n = 7); Experimental group Thermogenic C4 (GT1) - Rats undergoing orthodontic movement and daily dose of thermogenic C4 (n = 8) and experimental Group Thermogenic PRE-HD (GT2) - Rats submitted to orthodontic movement and daily dose of thermogenic PRE-HD (n = 4). The analysis of orthodontic movement was done by obtaining the difference in distance (in mm) from the distal of the 1˚ molar left superior to the mesial of the 2˚ molar superior of the same side, a measurement performed in the cervical region with the aid of a tip compass dry; the systemic analysis was performed through biochemical and leukogram tests and the behavioral study through the open field test. Results: There was no statistically significant difference between groups GT1, GT2 and CG regarding the amount of orthodontic movement (p> 0.005). Regarding the open field test, there was a statistically significant difference (p <0.005) between the groups for the variables: ambulatory movements, standing movements, number of jumps, distance traveled, speed of distance traveled and movements performed in the center and on the edges.Regarding the systemic effects, the leukogram and the biochemical tests performed did not show significant results. Conclusion: The use of thermogenics has no influence on the rate of orthodontic movement in rats and does not produce relevant systemic changes, however, it is capable of affecting several aspects of the behavior of these animals (AU).

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Abstract Objective: To investigate the effects of application of vibratory stimuli, using an electric toothbrush, on the rate of orthodontic tooth movement during maxillary canine retraction. Methods: A split-mouth study was conducted in 28 subjects (mean age = 20.8 years; ranging from 18 to 24 years) whose bilateral maxillary first premolars were extracted with subsequent canine retraction. On the Vibration side, light force (100 g) was applied to the canine for 90 days, in combination with vibratory stimuli provided by an electric toothbrush; only orthodontic force was applied to the canine on the non-vibration side. Amount of canine movement was measured monthly. Related to electronic toothbrush usage, a diary was provided to each patient for recording discomfort during experimental period, having 100-mm visual analogue scale (VAS). The paired t-test was used to assess the differences in amount of tooth movement between canines of the vibration and non-vibration sides. Results: The amount of tooth movement was similar for canines on the vibration side and on the non-vibration side (mean 0.81 ± 0.10 mm and 0.82 ± 0.11 mm, respectively, p> 0.05). Plaque accumulation was minimal in any subject throughout the study. No subject reported discomfort as a result of using the electric toothbrush. Conclusions: This study demonstrates that application of vibratory stimuli using an electric toothbrush, in combination with light orthodontic force, do not accelerate orthodontic tooth movement.

Resumo Objetivo: investigar os efeitos da aplicação de estímulo vibratório, usando escova elétrica, sobre a taxa de movimentação dentária ortodôntica durante a retração dos caninos superiores. Métodos: um estudo de boca-dividida foi realizado em 28 pacientes (idade média de 20,8 anos, variando entre 18 e 24 anos) cujos dois primeiros pré-molares superiores foram extraídos, com subsequente retração dos caninos. No lado Com Vibração, uma força leve (100g) foi aplicada no canino durante 90 dias, em combinação com o estímulo vibratório gerado por uma escova de dentes elétrica; enquanto os caninos do lado Sem Vibração foram submetidos apenas à aplicação da força ortodôntica. A quantidade de movimentação dos caninos foi aferida mensalmente. Quanto ao uso da escova de dentes elétrica, diários foram fornecidos aos pacientes para que esses anotassem, em Escalas Visuais Analógicas (EVA) de 100 mm, o desconforto sentido durante o período experimental. O teste t pareado foi utilizado para avaliar as diferenças na quantidade de movimentação dos caninos nos lados Com Vibração e Sem Vibração. Resultados: os valores da movimentação dentária foram semelhantes nos lados Com Vibração e Sem Vibração (médias de 0,81 ± 0,10 mm e 0,82 ± 0,11 mm, respectivamente, p> 0,05). O acúmulo de placa dentária nos pacientes dessa amostra foi mínimo, ao longo de todo o estudo. Nenhum paciente relatou desconforto durante o uso da escova elétrica. Conclusões: o presente estudo demonstrou que a aplicação de estímulo vibratório usando uma escova elétrica, associada a forças ortodônticas leves, não foi capaz de acelerar a movimentação dentária ortodôntica.

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BACKGROUND: Type 1 diabetes (T1D) is associated with delayed tissue healing and bone loss. Periodontal tissues during tooth movement (OTM) in T1D and under diabetic treatment are poorly understood. We aimed to study the effect of metformin as an add-on to insulin therapy on periodontal structures during OTM in T1D rats. METHODS: Rats were divided into normoglycemic (NG, n = 20) and streptozotocin-induced diabetic groups that were untreated (T1D, n = 20), treated with insulin (I-T1D, n = 20), or treated with insulin plus metformin (IM-T1D, n = 20). After 7 days of treatment, the first right upper molar (M1) was moved mesially. At days 0, 3, 7 and 14, the pattern of OTM and the periodontal tissues were analyzed by micro-CT, histomorphometry, and immunohistochemistry for TRAP. RESULTS: In T1D, major osteoclastogenic activity and bone loss versus other groups were confirmed by a greater TRAP-positive cell number and reabsorption surface on both the pressure and tension sides for 14 days (p < 0.01). Additionally, we observed low bone volume density. Metformin plus insulin resulted in a daily insulin dose reduction and major glycemic control versus I-T1D. Although no significant differences were observed between I-T1D and IM-T1D, the tooth displacement and inclination, periodontal ligament thickness, and alveolar bone density on the pressure side in IM-T1D were similar to that of NG (p > 0.05). CONCLUSION: Antidiabetic treatment reduces severe periodontal damage during applied orthodontic force in T1D untreated rats. Metformin as an add-on to insulin therapy resulted in glycemic control and a periodontal tissue response to orthodontic forces that was similar to that of normoglycemic rats.

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The in vivo response of osteocytes to different force magnitudes soon after they are applied remains to be elucidated. The aim of this study was to examine the early effects of applying a very light (LF: 0,16 N) and a very strong (SF: 2,26 N) orthodontic force during one hour on apoptosis and osteopontin (OPN) expression on alveolar bone osteocytes, in rats. Results: LF: compared to the control group, they showed a significant increase in OPN expression, and a significant decrease in the number of TUNELpositive osteocytes. SF: compared to the control group, they showed a significant increase in OPN expression and a significant decrease in the number of TUNELpositive osteocytes. Our results show that osteocytes respond very early to the application of tension and pressure forces of different magnitudes, and application of forces decreases the number of apoptotic osteocytes and increases OPN expression. These results allow concluding that osteocytes activate rapidly when subjected to locally applied forces, whether these forces be pressure or tension, light or strong forces.

Hasta el momento no se ha dilucidado la respuesta temprana in vivo de los osteocitos a la aplicación de fuerzas de diferentes magnitudes sobre el hueso. El objetivo de este estudio fue examinar la respuesta temprana de la aplicación de una fuerza ortodóncica muy liviana (FL: 0,16 N) y muy fuerte (FF: 2,26 N) durante una hora sobre la expresión de apoptosis y osteopontina (OPN) en los osteocitos del hueso alveolar, en ratas. Resultados: FL: en comparación con el grupo control, mostraron un aumento significativo en la expresión de OPN y una disminución significativa en el número de osteocitos TUNELpositivos. FF: en comparación con el grupo control, mostraron un aumento significativo en la expresión de OPN y una disminución signi ficativa en el número de osteocitos TUNELpositivos. Nuestros resultados muestran que los osteocitos responden muy temprano a la aplicación de fuerzas de tensión y presión de diferentes magnitudes, y la aplicación de fuerzas disminuye el número de osteocitos apoptóticos y aumenta la expresión de OPN. Estos resultados permiten concluir que los osteocitos se activan rápidamente cuando se los somete a fuerzas aplicadas localmente, ya sean estas fuerzas de presión o tensión, livianas o fuertes.

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