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.

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.

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.

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.