Biomodulation of Induced Tooth Movement by Three Methods, Corticopuncture, Photobiomodulation, and Their Combination: An Animal Study.

Objective: The aim of this study was to assess the effects of accelerated tooth movement (ATM) methods: corticopuncture (CP), photobiomodulation (PBM), and their combination (CP + PBM) by evaluating tooth displacement, alveolar bone changes, and molecular and cellular response compared with conventional induced tooth movement. Materials and methods: Tooth movement and bone changes were evaluated on days 1, 3, and 7 (9 animals per time point) using microtomography, histological, and immunohistochemical evaluation, at compression and tension sites. CP groups received two perforations in the palate and one mesial to the molars. PBM was performed using GaAlAs diode laser applied every other day for 7 days (λ = 808 nm, 100 mW) in two points for 15 sec/point and total energy of 3 J. Results: Tooth movement was significantly increased in all three ATM groups after 7 days compared with the control group (mean 0.24 mm) by 27% PBM (0.31 mm), 45% CP (0.35 mm), and 57% CP + PBM (0.38 mm) (p < 0.05). At the compression side, all ATM groups showed significant decrease in bone density on day 3 (p < 0.05) and significant less bone volume on day 7 compared with Control (p < 0.05). At the tension side, PBM group showed a significant increase in bone density and volume on day 3 (p < 0.05). Immunohistochemistry analysis showed that at the compression side, tartrate-resistant acid phosphatase-positive cells, RANKL, and tumor necrosis factor-alpha expression were highly marked of the PBM and the combined method groups (p < 0.05). PBM and CP + PBM groups showed a significant increase in expression Runt-related transcription factor 2 and osterix (p < 0.05) at the tension side. Conclusions: All ATM groups showed increase on tooth displacement with CP + PBM group showing greatest tooth displacement. CP method appears to stimulate bone catabolism, PBM has more effect on bone formation, and the combined method showing a synergistic effect on bone remodeling.

In vitro effects of photobiomodulation on cell migration and gene expression of ALP, COL-1, RUNX-2, and osterix in cementoblasts.

The aim of this study was to evaluate the effects of photobiomodulation (PBM) on cell migration and alkaline phosphatase (ALP), type I collagen (Col-1), runt-related transcription factor 2 (RUNX-2), and Osterix (OSX) gene expression in a cementoblast culture (OCCM-30), in a microenvironment mimicking an injury on the cementoblast layer, such as it occurs during root resorption. For this, OCCM-30 cells were cultured in 6-well plates and the following parameters were assayed: (1) migration by scratch assay and ALP, Col-1, Runx2, and Osx by real-time PCR. PBM was performed in two protocols using a LED device emitting light at 660 nm (± 30 nm). OCCM-30 cementoblasts were grown and divided into four groups: (1) negative control; (2) positive control (scratch); (3) scratch + PBM with a total energy of 36 J and energy density 1.6 J/cm2; and (4) scratch + PBM with a total energy of 72 J and energy density of 3.2 J/cm2. Data were statistically analyzed, with the level of significance set at 5%. Cementoblasts migrated from the edge of the scratch toward the center, and the wound closed after 24 h, with the PBM3.2J/cm2 group showing the higher cell migration compared with the other groups at 2 h, 6 h, 8 h, and 13 h (p < 0.05). The control and PBM1.6J/cm2 groups showed similar levels of cell migration, with no significant differences (p > 0.05). PBM3.2J/cm2 group exhibited greater ALP, Col-1, OSX, and RUNX2 in comparison with the other experimental groups (p < 0.05). Similar levels of all genes evaluated were observed between the PBM1.6J/cm2 group and the positive control group (p > 0.05). In conclusion, our findings support the effectiveness of photobiomodulation on cementoblast migration and gene expression, which may contribute to the formation of a new cementum layer.

Can Collagen Membrane on Bone Graft Interfere with Light Transmission and Influence Tissue Neoformation During Photobiomodulation? A Preliminary Study.

Objective: This study qualitatively and quantitatively evaluated the transmission of light through a collagen membrane and the consequent local bone formation in a critical bone defect in vitro and in an animal model. Background: Currently, bone substitutes and collagen membranes are used to promote new bone formation; however, when associated with photobiomodulation, biomaterials can act as a barrier, hindering the passage of light radiation to the area to be treated. Methods: Light transmittance was evaluated in vitro with a power meter and a 100 mW, 808 nm laser source with and without membrane. Twenty-four male rats received a critical surgical defect of 5 mm in diameter in the calvarial bone, subsequently a biomaterial (Bio-Oss; Geistlich®, Switzerland) was applied, and the animals were divided into the following three groups: G1-collagen membrane and no irradiation; G2-collagen membrane and photobiomodulation (irradiation with 4 J of 808 nm); and G3-photobiomodulation (4 J) followed by a collagen membrane. Histomophometric analyses were performed at 7 and 14 days after euthanasia. Results: The membrane reduced the light transmittance (808 nm) by an average of 78%. Histomophometric analyses showed significant differences in new blood vessels on day 7 and bone neoformation on day 14. Irradiation without membrane interposition resulted in a 15% more neoformed bone compared with the control (G1), and 6.5% more bone compared with irradiation over the membrane (G2). Conclusions: The collagen membrane interferes with light penetration during photobiomodulation, decreases light dosimetry on the wound area, and interferes with bone neoformation.

UV-C light as an alternative for disinfecting orthodontic pliers / Luz UV-C como alternativa para desinfecção de alicates ortodônticos

Objetivo: Os ortodontistas usam alicates ortodônticos continuamente, e essas ferramentas têm um forte potencial para infecções nosocomiais. Este estudo teve como objetivo comparar a eficiência de três métodos de desinfecção de alicates ortodônticos. Material e Métodos: As pontas ativas de 26 alicates ortodônticos (cortadores distais e alicates Weingart) foram contaminadas com microrganismos, vírus e esporos S. aureus, E. coli e C. albicans. Os métodos de controle microbiano foram desinfecção com álcool 70%, esterilização com esferas de vidro (250 °C calor seco) e irradiação com luz ultravioleta (250 nm UV-C) por 30 e 60 segundos. O número de unidades formadoras de colônias (UFC) e unidades formadoras de placas (UFP) foi quantificado e comparado para cada microrganismo após incubação em placas de cultura. Resultados: Todas as pontas do alicate dos grupos que receberam luz ultravioleta ou foram submetidos à esterilização com esferas de vidro apresentaram número significativamente menor de esporos, bactérias e fungos do que suas respectivas amostras controle (p<0,001). A desinfecção física com luz UV-C pode representar uma alternativa confiável em comparação com outros métodos químicos e físicos devido ao aumento de microrganismos resistentes a produtos químicos e à emissão de subprodutos nocivos após o tratamento químico. Conclusão: Os métodos de controle microbiano testados foram eficazes na desinfecção de alicates ortodônticos, tornando a luz ultravioleta-C uma alternativa promissora para eliminar os microrganismos dos alicates (AU)

Objective: Orthodontists use orthodontic pliers continuously, and these tools have a strong potential for nosocomial infections. This study aimed to compare the efficiency of three methods for disinfecting orthodontic pliers. Material and Methods: The active tips of 26 orthodontic pliers (distal end cutters and Weingart pliers) were contaminated with S. aureus, E. coli, and C. albicans microorganisms, viruses, and spores. The microbial control methods were 70% alcohol disinfection, glass bead sterilization (250 °C dry heat), and ultraviolet light irradiation (250 nm UV-C) for 30 and 60 seconds. The number of colony-forming units (CFU) and plaque-forming units (PFU) was quantified and compared for each microorganism after incubation in culture plates. Results: All tips of the pliers in the groups that received ultraviolet light or were subjected to glass bead sterilization showed a significantly lower number of spores, bacteria, and fungi than their respective control samples (p<0.001). Physical disinfection with UV-C light may represent a reliable alternative compared to other chemical and physical methods due to the increase in microorganisms resistant to chemical products and the emission of harmful by-products after chemical treatment. Conclusion: The tested microbial control methods were effective in the disinfection of orthodontic pliers, making ultraviolet-C light a promising alternative to eliminate microorganisms from pliers (AU)

Photobiomodulation stimulates surrounding bone formation and increases stability of titanium alloy miniscrews in ovariectomized rats.

The number of older individuals (> 60 years) treated in orthodontic dental practice is constantly growing, and osteoporosis is a common disease within this age range. Orthodontic treatment for this group tends to be challenging, often requiring the use of mini-implants. Mini-implants are important accessories in orthodontic treatment that provide solutions to complex cases. Despite the high level of success, these devices are prone to failure if insufficient bone stability is achieved. This study aimed to evaluate the effects of photobiomodulation on bone neoformation around mini-implants using fluorescence analysis in ovariectomized rats. A total of 12 female rats (Wistar) were ovariectomized and divided into three groups: two groups of low-level laser therapy irradiation in two different protocols, as follows: in the PBM1 group, applications were performed using 2 J, for 20 s each for 48 h, 6 irradiations in total, and in the PBM2 group, a single application of 4 J was performed for 40 s, and the third group represented the control group, and no laser therapy was applied. Each rat received two mini-implants placed immediately behind the upper incisors, and 0 g of force was applied using a NiTi spring. All rats received two bone markers, tetracycline (days 0-4) and alizarin (days 7-10), for 5 days each. Both markers were bound to calcium, allowing visualization of bone neoformation through fluorescence microscopy. After 12 days, euthanasia was performed; the results revealed that both irradiated groups showed significantly greater bone neoformation compared to the control group (p < 0.05). Mini-implant stability was measured in all animals using the Periotest device on day 0 and on the day of euthanasia. A significant increase in stability was observed in the group that received more laser application (p < 0.05). Photobiomodulation had a positive effect on bone neoformation around mini-implants in ovariectomized rats, with an increase in stability when more irradiation was performed.

Assessment of a Biosafety Device to Control Contamination by Airborne Transmission during Orthodontic/Dental Procedures.

During the COVID-19 pandemic, dental professionals have faced high risk of airborne contamination between dentists, staff, and patients. The objective of this study was to evaluate the effect of an individual biosafety capsule in dentistry (IBCD) on reducing the dispersion of droplets and aerosols during orthodontic treatment and evaluate the clinician and patient's perception of using the IBCD. For the in-vitro part of the study, aerosol quantification was performed with and without the IBCD, using a nonpathogenic bacterial strain and viral strain in the reservoir and high-speed dental handpiece. Petri dishes with MRS agar were positioned from the head of the equipment at distances of 0.5, 1, and 1.5 m. After 15 minutes of passive aerosol sampling, the dishes were closed and incubated using standard aerobic conditions at 37°C for 48 hours to count colony forming units (CFUs). For the clinical part of the study, a questionnaire was sent to clinicians and patients to understand their perception of orthodontically treat and receive treatment using the barrier. The use of IBCD showed an effective means to reduce the dispersion of bacterial and viral contamination around 99% and 96%, respectively, around the main source of aerosol (p < 0.05). Clinical results showed a 97% bacterial reduction during patient's consultations (p < 0.05). The vast majority of clinicians and patients understand the importance of controlling the airborne dispersion to avoid contamination.

Análise da deformação e caracterização de mini-implantes utilizados no MARPE (miniscrew-assisted rapid palatal expander) / Analysis of deformation and characterization of miniscrews used in MARPE (miniscrew-assisted rapid palatal expander)

O objetivo deste trabalho foi analisar e caracterizar alterações estruturais e/ou deformações dos mini-implantes utilizados como ancoragem no disjuntor tipo MARPE (do inglês, Miniscrew-Assisted Rapid Palatal Expander). A amostra consistiu de quarenta e quatro mini-implantes (Peclab, Belo Horizonte/MG/Brasil) ­ comprimento: 7mm, pescoço: 4mm e diâmetro: 1,8mm) usados como ancoragem no disjuntor tipo MARPE em pacientes com constrição maxilar necessitando de tratamento para expansão rápida da maxila. Os mini-implantes analisados permaneceram em um período estimado de quatro meses na boca. Além disso, outros quatro mini-implantes novos e não usados fabricados pela mesma empresa foram usados como grupo controle. A análise e caracterização da deformação morfológica foram realizadas utilizando microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva de raios-X (EDS). Em relação à caracterização dos mini-implantes no segmento pescoço, encontrou-se uma composição média de titânio 85,99%, alumínio 5,48%, vanádio 1,72%, carbono 4,74%, cromo 0,15%, oxigênio 1,82%, Na região do terço médio, foram encontrados: titânio 82,37%, alumínio 5,33%, vanádio 1,89%, carbono 6,97%, cromo 0,11%, oxigênio 3,13%, enxofre 0,02%, ferro 0,08% e molibdênio 0,02%. Quando avaliada a deformação, segundo método proposto por Fujii (2013) variando do escore 0 (mínimo) à classificação 4 (máximo), foram observados os seguintes resultados: terço médio 1,70, ponta 1,56, cabeça 1,40 e pescoço 1,00. Nenhuma das amostras apresentou deformação ao longo do eixo dos mini-implantes. Um grande número de elementos na composição da liga foi detectado e as principais deformações foram de amassamento e edentação, principalmente, observados nos segmentos do terço médio e da ponta. (AU)

The aim of this work was to analyze and characterize structural changes and/or deformation of miniscrews used as anchorage for Miniscrew-Assisted Rapid Palatal Expander (MARPE). The sample consisted of forty-four miniscrews (Peclab, Belo Horizonte/MG/Brazil), length: 7mm, neck: 4mm and diameter: 1.8mm used as MARPE anchorage in patients with maxillary con- striction requiring rapid maxillary expansion treatment. The miniscrews analyzed remained an estimated period of four months in mouth. In addition, other four new and unused miniscrews manufactured by the same company were used as control group. Morphologic deformation analysis and characterization were performed using scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). Regarding miniscrews characterization at the neck segment, it was found an average composition of titanium 85.99%, aluminum 5.48%, vanadium 1.72%, carbon 4.74%, chrome 0.15%, oxygen 1.82%. In the middle third region it was found: titanium 82.37%, aluminum 5.33%, vanadium 1.89%, carbon 6.97%, chromium 0.11%, oxygen 3.13%, sulfur 0.02%, iron 0.08% and molybdenum 0.02%. When deformation was assessed, according to the method proposed by Fujii (2013) ranging from score 0 (minimum) to 4 (maximum), the following results were observed: middle third 1.70, tip 1.56, head 1.40 and neck 1.00. None of the samples showed deformation along the miniscrews axis. A large number of elements in the alloy composition were detected and the major deformations were mainly kneading and edentation, observed at the middle third and tip segments. Descriptors: Palatal expansion technique, orthodontic anchorage procedures, malocclusion.(AU)

Aligner Tubes ­ uma nova opção para a correção ortodôntica sem a utilização de bráquetes / Aligner Tubes ­ a new option for orthodontic correction without the use of brackets

Resumo O número de pacientes adultos que buscam o tratamento ortodôntico tem aumentado e essa mudança no cenário da Ortodontia tem exigido dos profissionais o emprego de aparelhos estéticos que proporcionem a correção das más oclusões por meio de abordagens simplificadas, eficientes e de maior conforto. Assim sendo, este artigo tem como objetivo apresentar uma técnica alternativa que pode ser empregada pelos profissionais na correção de más oclusões simples e na resolução de recidivas de apinhamento dentário na região anterior do arco. O artigo descreve a confecção passo a passo do sistema Aligner Tubes que é constituído por tubos metálicos colados às faces vestibulares dos elementos dentários anteriores e na sequência ilustra a aplicabilidade desse método com a exemplificação de relato de um caso clínico. Conclui-se que é um sistema simplificado, estético e de baixo custo que possibilita a correção dos problemas simples, em tempo relativamente curto e com resultados satisfatórios.(AU)

Abstract The number of adult patients searching for orthodontic treatment has increased and this change in the Orthodontic routine has required from professionals the use of aesthetic devices that provide malocclusions correction through simplified, efficient, and more comfortable approaches. Therefore, this article aims to present an alternative technique that can be used by professionals in the correction of minor malocclusions and in the resolution of dental crowding recurrences in the anterior region of the arch. This article describes the step-by-step preparation of the Aligner Tubes system, which consists of metallic tubes bonded to the buccal surfaces of the anterior teeth and then illustrates the applicability of this method with one clinical case report example. It is concluded that it is a simplified, aesthetic, and low cost system that allows the correction of simple problems in a relatively short time and with satisfactory results.(AU)

Evaluation of the cephalometric centroid point in individuals before and after the pubertal growth peak / Avaliação do comportamento do ponto cefalométrico centróide em pacientes antes e após o pico de crescimento da puberdade

ABSTRACT Objective: The purpose of this study was to evaluate the behavior of the Centroid point, known as the geometric center of the face, before and after the growth peak using lateral cephalometric x-ray. Methods: Sample consisted of 40 patients before and after pubertal peak of growth selected from the archive of the São Leopoldo Mandic Institute and Research Center, Campinas, Brazil. Anatomical structures, reference points, lines and planes were traced, and posteriorly a superimposition was performed using the palatal plane and a line perpendicular to this passage through the most posterior point of the pterygomaxillary fossa as reference. Later, the distance between the two centroid points (before and after the peak of puberty) was measured using the digital caliper, both horizontally and vertically. The palatal plane (x-axis) and a line perpendicular to this passage through the most posterior point of the pterygomaxilary fossa (y-axis) were chosen because they undergo minimal changes during growth. Results: No significant difference on the location of Centroid points on both X and Y axis (p >0.05) were observed between before and after the growth peak cephalometric tracings, showing an average change in positioning of 0.36mm on the X axis and 0.37mm on the Y axis. Conclusions: For this reason, this point can be indicated to be used clinically as a stable reference to evaluate craniofacial growth while performing superimposition methods.

RESUMO Objetivo: O objetivo deste estudo foi utilizar telerradiografias lateriais de pacientes antes e depois do pico de crescimento, e realizar sobreposições de desenhos cefalométricos para avaliar o comportamento do ponto Centróide, o centro geométrico da face. Métodos: Foram selecionadas telerradiografias de norma lateral de 40 pacientes tomadas antes e depois de seu pico de puberdade do acervo de Ortodontia do Centro de Pesquisas Odontológicas São Leopoldo Mandic, na cidade de Campinas. As estruturas e traçados cefalométricos devidamente desenhados, foram sobrepostos tendo como referência estável o plano palatal e a linha perpendicular a esta que passe pelo ponto mais posterior da fossa pterigomaxilar. Em seguida foi medida a distância entre os dois pontos centroides (antes e após o pico de puberdade) por meio de paquímetro digital tanto no sentido horizontal quanto no vertical. O plano palatal (eixo x) e a linha perpendicular a esta que passe pelo ponto mais posterior da fossa pterigomaxilar (eixo y) foram escolhidos por sofrerem mínimas alterações nas suas direções durante o crescimento. Resultados: Não foi observada diferença estatisticamente significante na localização dos pontos Centróides em ambos os eixos X e Y (p>0,05) quando comparou-se os traçados antes e depois do pico de crescimento, mostrando uma alteração, em média, no posicionamento de 0,36mm no Eixo X e 0,37mm no Eixo Y. Conclusão: Assim, este ponto pode ser utilizado como referência estável para avaliação do crescimento craniofacial nas sobreposições.

Antimicrobial activity of probiotics against oral pathogens around orthodontic mini-implants: an in vitro study.

OBJECTIVE: The aim of this in vitro study was to evaluate the antimicrobial effect of five types of non-industrialized and industrialized probiotics on biofilms formed around orthodontic mini-implants. The null hypothesis tested was: there is no difference in the antimicrobial effect between the five types of probiotics tested around orthodontic mini-implants. METHODS: For the experiment, 120 mini-implants were immersed for seven days in Staphylococcus aureus solution for biofilm formation, and were subsequently plated in culture medium containing probiotics. The mini-implants were divided into six different groups, according to the probiotic used: G1)Lactobacillus casei; G2)Lactobacillus brevis; G3)Lactobacillus rhamnosus; G4) Lactobacillus from fermented milk Yakult®; G5) Lactobacillus from fermented milk Batavito® and G6) without use of probiotic, as negative control. Qualitative and quantitative analyses of all groups were performed using the CFU (colony forming unit) count. RESULTS: The study showed that groups G4 and G6 did not present antimicrobial activity, in comparison to groups G1, G2, G3, and G5 (p< 0.05), which demonstrated antimicrobial activity. CONCLUSION: The non-commercial probiotic bacteria, Lactobacillus casei and Lactobacillus rhamnosus, as well as commercially available fermented milk Batavito® presented promising results in the reduction of colonization of mini-implants by S. aureus. Therefore, the null hypothesis was rejected.

Photodynamic Therapy and Photobiomodulation on Oral Lesion in Patient with Coronavirus Disease 2019: A Case Report.

Objective: This article reports the case of a patient with oral manifestation of coronavirus disease 2019 (COVID-19) treated with photobiomodulation (PBM) and photodynamic therapy (PDT). Background: Some dermatological and oral mucosal lesions have recently been linked to severe acute respiratory syndrome coronavirus 2 infection. Methods: A 65-year-old female patient with a confirmed real-time reverse transcriptase-polymerase chain reaction diagnosis of COVID-19 presented with dry edematous lips, edema with mucosal desquamation, ulceration and blood crust on the inner aspect of the lips, gingival petechiae and erythematous and pseudomembranous lesions on the dorsum of the tongue. The treatment protocol was three sessions of antimicrobial PDT (aPDT) (660 nm diode laser + methylene blue) to the lips and tongue, every 24 h to control contamination, followed by PBM (low-power laser, 100 mW, 2 J/point) to the lips, tongue, and oral mucosa for additional four sessions every 24 h. Results: Therapy association promoted pain control and healing of oral mucosal lesions in 7 days of treatment. Conclusions: PBM and aPDT could be an interesting approach to manage COVID-19 patients.

Antimicrobial activity of probiotics against oral pathogens around orthodontic mini-implants: an in vitro study

ABSTRACT Objective: The aim of this in vitro study was to evaluate the antimicrobial effect of five types of non-industrialized and industrialized probiotics on biofilms formed around orthodontic mini-implants. The null hypothesis tested was: there is no difference in the antimicrobial effect between the five types of probiotics tested around orthodontic mini-implants. Methods: For the experiment, 120 mini-implants were immersed for seven days in Staphylococcus aureus solution for biofilm formation, and were subsequently plated in culture medium containing probiotics. The mini-implants were divided into six different groups, according to the probiotic used: G1)Lactobacillus casei; G2)Lactobacillus brevis; G3)Lactobacillus rhamnosus; G4) Lactobacillus from fermented milk Yakult®; G5) Lactobacillus from fermented milk Batavito® and G6) without use of probiotic, as negative control. Qualitative and quantitative analyses of all groups were performed using the CFU (colony forming unit) count. Results: The study showed that groups G4 and G6 did not present antimicrobial activity, in comparison to groups G1, G2, G3, and G5 (p< 0.05), which demonstrated antimicrobial activity. Conclusion: The non-commercial probiotic bacteria, Lactobacillus casei and Lactobacillus rhamnosus, as well as commercially available fermented milk Batavito® presented promising results in the reduction of colonization of mini-implants by S. aureus. Therefore, the null hypothesis was rejected.

RESUMO Objetivo: O objetivo do presente estudo in vitro foi avaliar o efeito antimicrobiano de cinco tipos de probióticos não industrializados ou industrializados em biofilmes formados ao redor de mini-implantes ortodônticos. A hipótese nula testada foi: não há diferença no efeito antimicrobiano entre os cinco tipos de probióticos testados em torno dos mini-implantes ortodônticos. Métodos: Para o experimento, as cabeças de 120 mini-implantes foram imersas por sete dias em solução de Staphylococcus aureus para formação de biofilme e, posteriormente, semeadas em meio de cultura contendo probióticos. Os mini-implantes foram divididos em seis grupos diferentes, de acordo com o probiótico utilizado: G1)Lactobacillus casei; G2)Lactobacillus brevis; G3)Lactobacillus rhamnosus; G4) lactobacilos do leite fermentado Yakult®; G5) lactobacilos do leite fermentado Batavito®; e G6) sem uso de probiótico, como controle negativo. As análises qualitativas e quantitativas de todos os grupos foram realizadas usando a contagem de UFCs (unidades formadoras de colônia). Resultados: O estudo mostrou que os grupos G4 e G6 não apresentaram atividade antimicrobiana, em comparação aos grupos G1, G2, G3 e G5 (p< 0,05), os quais demonstraram atividade antimicrobiana. Conclusão: As bactérias probióticas não comerciais, Lactobacillus casei e Lactobacillus rhamnosus, assim como o leite fermentado comercializado, Batavito®, apresentaram resultados promissores na redução da colonização dos mini-implantes por S. aureus. Portanto, a hipótese nula foi rejeitada.

Reliability of a Centroid method to estimate head position in cephalometric diagnosis / Confiabilidade de um método baseado no ponto Centróide para estimar a posição da cabeça no diagnóstico cefalométrico

ABSTRACT Objective The objective of this study was to 1) evaluate the reproducibility of natural head position (NHP) in different professional groups; 2) compare three cephalometric methods of estimating head position to the established natural head position and 3) investigate the applicability of a new method to estimated head position using a Centroid method. Methods The sample consisted of 105 individual cephalometric tracings and photographs. For the first evaluation, copies of the lateral photographs were reproduced for each patient and 3 professionals with different expertise (experienced orthodontists, orthodontic students and orthognatic surgeon) were instructed to position the photographs in NHP. Later, 3 different methods to obtain NHP were assessed: 1) the Frankfort Horizontal Plane (FRANK), 2) Sella-Nasion 7º Line (SN7) and 3) proposed Horizontal Reference Line based on Centroid. Angles formed by the evaluated planes/lines and True Vertical Line obtained were measured. Gender and skeletal discrepancy were considered. Results The results showed a significant difference between NHP obtained from orthodontists and surgeons compared to students (p<0.0001). Also results showed no effect of skeletal classification and gender did on measurement (p>0.05). Both SN minus 7º and FRANK methods showed a high variability (p < 0,01) compared to Centroid method. Conclusion NHP may be affected by the professional experience. The proposed horizontal line based on Centroid is a valid method for estimating head position, thus, may be indicated to use as a diagnostic tool in Orthodontics and Orthognatic Surgery.

RESUMO Objetivo Os objetivos deste estudo foram 1) avaliar a reprodutibilidade da posição natural da cabeça (PNC) em diferentes grupos de profissionais; 2) comparar três métodos cefalométricos para estimar a posição da cabeça e compará-los à posição natural estabelecida da cabeça e 3) investigar a aplicabilidade de um novo método para estimar a posição da cabeça usando o método Centróide. Métodos A amostra foi composta por 105 traçados cefalométricos e fotografias individuais. Para a primeira avaliação, cópias das fotografias laterais foram reproduzidas para cada paciente e três profissionais com diferentes conhecimentos (ortodontistas experientes, estudantes de ortodontia e cirurgião ortognático) foram instruídos a posicionar as fotografias no PNC. Posteriormente, foram avaliados três métodos diferentes para obter posição estimada da cabeça: 1) o Plano Horizontal de Frankfort (FRANK), 2) a Linha Sella-Nasion 7º (SN7) e 3) a Linha de Referência Horizontal proposta, baseada em Centróide. Os ângulos formados pelos planos/linhas avaliados e pela linha vertical verdadeira obtidos foram medidos. Foram considerados a discrepância esquelética e o gênero. Resultados Os resultados mostraram uma diferença significativa entre o PNC obtido por ortodontistas e cirurgiões em relação aos estudantes (p <0,0001). Os métodos SN7 e FRANK apresentaram alta variabilidade (p <0,01), enquanto o método baseado em Centróide mostrou menor variabilidade. Conclusão a PNC pode ser afetada pela experiência profissional. A linha horizontal proposta baseada em Centróide é um método válido para estimar a posição da cabeça, portanto, pode ser indicada para uso como ferramenta de diagnóstico em Ortodontia e Cirurgia Ortognática.

Effects of Photobiomodulation on Root Resorption Induced by Orthodontic Tooth Movement and RANKL/OPG Expression in Rats.

The aim of this study was to evaluate the effects of photobiomodulation on the repair of induced root resorption (RR) after orthodontic tooth movement. Twenty male rats were used in this study. Forty right and left upper first molars were evaluated and divided into four groups (n = 10): negative control group (NC), no tooth movement or irradiation; positive control group (PC), induced tooth movement and root resorption; conventional treatment group (CT), force was removed after 7 days; and photobiomodulation group (PBM) after force removal molars were irradiated every 48 h for 7 days using GaAlAs diode laser (810 nm). Energy per point was 1.5 J (100 mW, 15 s, 75 J cm-2 ). NC and PC were euthanized on day 7; CT and PBM on day 14. Histomorphometric and immunohistochemsitry analyses showed increase in area of root resorption in all groups (P < 0.05) compared to NC. RR lacunae were larger in CT compared to PC and PBM at the compression side of the distal root. OPG was higher in PBM group (P < 0.05). PBM group showed low expression of RANKL compared to PC and CT on the tension side. PBM can potentially affect RR progression by increasing OPG expression in the compression area and decreasing number of clastic cells in the root surface.

Photobiomodulation increases intrusion tooth movement and modulates IL-6, IL-8 and IL-1ß expression during orthodontically bone remodeling.

This study investigated the effects of photobiomodulation (PBM) on upper molar intrusion movement, regarding acceleration of orthodontic movement and its molecular effects. The sample consisted of 30 patients with indication of tooth intrusion for oral rehabilitation. Teeth were divided into three different groups: G1 (n = 10) pre-molars without force or laser application (control); G2 (n = 10) upper molar intrusion; and G3 (n = 10) upper molar intrusion and PBM. On PBM treated molars, the teeth were irradiated with a low-power diode laser (808 nm, 100 mW), receiving 1 J per point, density of 25 J/cm2 , with application of 10 s per point, 10 points (5 per vestibular and 5 per palatal region). Orthodontic force of intrusion applied every 30 days and PBM was performed immediately, 3 and 7 days after force application for 3 months. Gingival crevicular fluid was collected at the same time periods as the laser applications and interleukins (IL) 1-ß, -6 and -8 were evaluated by enzyme-linked immunosorbent assay. Clinical measures were performed monthly to verify the amount of intrusion. The levels of IL-6, IL-8 and IL-1ß increased under orthodontic force (G2 and G3) when compared to control group (G1), however, the cytokines levels were significantly higher after PBM (G3). The mean intrusion velocity was 0.26 mm/month in the irradiated group (G3), average duration of 8 months vs 0.17 mm/month for the non-irradiated group (G2), average duration of 12 months. This study suggests that PBM accelerates tooth movement during molar intrusion, due to modulation of IL-6, IL-8 and IL-1ß during bone remodeling.

Effects of maxillary skeletal expansion on respiratory function and sport performance in a para-athlete - A case report.

The aim of this case report was to demonstrate the effects of the Maxillary Skeletal Expander (MSE) used to orthopedically correct a maxillary constriction, on the respiratory functions and swimming performance of a Para-athlete. Cone-beam computed tomography (CBCT) images taken before and after MSE activation were used to demonstrate the disarticulation of midpalatal suture, and the changes involved in dental and nasomaxillary structures, nasal cavity and pharyngeal airway. Respiratory tests included: maximum inspiratory and expiratory pressure, oral peak expiratory flow and inspiratory nasal flow. The 6-min-walk and heart rate recovery tests were also performed. Patient's swimming performances during national swimming competitions were compared. CBCT images showed that palatal expansion was 5.91  mm at the suture, and that nasal and pharyngeal airways increased in volume by 31%. All respiratory indices improved after MSE activation. The 6-min walk test and heart rate recovery test performance also improved after the maxillary expansion. Patient's swimming performance in all category were anemic prior to the treatment, but performance improved considerably after the expansion, particularly the 100 m-Backstroke modality. MSE treatment had a significant positive impact in respiratory functions and sport performance.

Corticopuncture Facilitated Microimplant-Assisted Rapid Palatal Expansion.

INTRODUCTION: Microimplant-assisted rapid palatal expansion (MARPE) has been considered an alternative to avoid extensive surgical procedures. In order to obtain skeletal results of MARPE, force should be enough to overcome areas of resistance and the first one that is required to be disrupted is the midpalatal suture, which becomes increasingly interdigitated after adolescence. OBJECTIVE: The present study aimed at providing a novel approach using a minimally invasive method called corticopuncture (CP) in association with MARPE illustrated by a case report of a 35-year-old Brazilian female Caucasian patient presenting maxillary transverse deficiency. METHOD: Treatment plan started with an orthopedic correction of the transverse problem using a MARPE device. After many unsuccessful attempts to activate MARPE, corticopunctures were performed along the midpalatal suture. CP procedure at the midpalatal suture included 8 perforations (2 mm apart), performed after previous predrilling followed by miniscrew insertion (5 mm thread length and 1.8 mm diameter). RESULTS: After CP and new activation protocol, the opening of the midpalatal suture was observed by CBCT images, showing skeletal results, suture split of 3.14 mm (premolar area) and 2.06 (molar area), an increase of 4.3 mm (premolar) and 3.03 mm (molar) in basal bone width, 4.43 mm (premolar) and 3.1 mm (molar) in cortical bone width, and minimal dental effects (mean of 1.2° of tooth tipping). CONCLUSION: The combination of MARPE and corticopuncture method was proved to be a nonsurgical treatment option to correct maxillary transverse deficiency in an adult patient. CP was able to weaken suture interdigitation thus facilitating the split.

Effects of corticopuncture (CP) and low-level laser therapy (LLLT) on the rate of tooth movement and root resorption in rats using micro-CT evaluation.

The aim of this study was to compare the rate of tooth displacement, quantity of root resorption, and alveolar bone changes in five groups: corticopuncture (CP), low-level laser therapy (LLLT), CP combined with LLLT (CP + LLLT), control (C), and negative control (NC). A total of 60 half-maxilla from 30 male Wistar rats (10 weeks old) were divided randomly into five groups: three (CP, LLLT, and CP + LLLT) test groups with different stimulation for accelerated-tooth-movement (ATM), one control (C) group, and one negative control (NC) group with no tooth movement. Nickel-titanium coil springs with 50 g of force were tied from the upper left and right first molars to micro-implants placed behind the maxillary incisors. For the CP and CP + LLLT groups, two perforations in the palate and one mesially to the molars were performed. For the LLLT and CP + LLLT groups, GaAlAs diode laser was applied every other day for 14 days (810 nm, 100 mW, 15 s). The tooth displacements were measured directly from the rat's mouth and indirectly from microcomputer (micro-CT) tomographic images. Bone responses at the tension and compression sites and root resorption were analyzed from micro-CT images. The resulting alveolar bone responses were evaluated by measuring bone mineral density (BMD), bone volume fraction (BV/TV), and trabecular thickness (TbTh). Root resorption crater volumes were measured on both compression and tension sides of mesial and distal buccal roots. The tooth displacement in the CP + LLLT group was the greatest when measured clinically, followed by the CP, LLLT, and control groups (C and NC), respectively (p <0.05). The tooth movements measured from micro-CT images showed statistically higher displacement in the CP and CP + LLLT groups compared to the LLLT and control groups. The BMD, BV/TV, and TbTh values were lower at the compression side and higher at the tension side for all three test groups compared to the control group. The root resorption crater volume of the distal buccal root was higher in the control group, followed by CP, LLLT, and CP + LLLT, mostly at the compression site. Combining corticopuncture and low-level laser therapy (CP + LLLT) produced more tooth displacement and less root resorption at the compression side. The combined technique also promoted higher alveolar bone formation at the tension side.

Effects of Photobiomodulation on SOFAT, A T-cell-derived Cytokine, May Explain Accelerated Orthodontic Tooth Movement.

Orthodontic tooth movement is based on mechanical forces inducing bone remodeling, and several methods have been proposed to increase tooth movement, including photobiomodulation. This study evaluated, in an animal model, the effects of photobiomodulation on SOFAT-a secreted osteoclastogenic factor of activated T cells and RANK-L during tooth movement. The results showed that tooth displacement, RANK-L and SOFAT levels were significantly greater compared to Control group. SOFAT may play an important role in bone remodeling during orthodontic movement, possibly increasing the osteoclast cells at the compression area and bone remodeling activity.