Orthodontic treatment in traumatized permanent teeth: a systematic review / Tratamento ortodôntico em dentes permanentes traumatizados: uma revisão sistemática

Objective: to analyze, through literature review, the available literature on orthodontic treatment in traumatized permanent teeth. Methods: A literature search was performed in electronic databases (PubMed and SciELO) using the descriptors [tooth injuries] OR [injuries, teeth] OR [injury, teeth] OR [teeth injury] OR [injuries, tooth] OR [injury, tooth] OR [tooth injury] OR [teeth injuries] AND [orthodontics]. Observational studies and clinical trials were included, narrative reviews, laboratory and in vitro studies, case reports and series as well as articles that presented abstracts written in languages other than Portuguese, English and Spanish were excluded from the study. Two reviewers considered the eligibility, the risk of bias of the analyzed data and the qualitative synthesis of the studies included. A total of 1,322 references were found and 4 articles met all inclusion criteria and were included in the qualitative analysis. Some consequences like pulp necrosis and root resorption have been highlighted and trauma severity should be considered when orthodontically intervening in previously traumatized teeth. Final considerations: The traumatized teeth can be orthodontically treated as long as the time of tissue reorganization is respected, and the pull and periodontal conditions are followed up.(AU)

Objetivos: analisar, por meio de revisão de literatura, a respeito do tratamento ortodôntico em dentes permanentes traumatizados. Metodologia: Uma pesquisa bibliográfica foi realizada em bancos de dados eletrônicos (PubMed e SciELO) usando os descritores [tooth injuries] ou [injuries, teeth] ou [injury, teeth] ou [teeth injury] ou [injuries, tooth] ou [injury, tooth] ou [tooth injury] ou [teeth injuries] e [orthodontics]. Foram incluídos estudos observacionais e ensaios clínicos, revisões narrativas, estudos laboratoriais e in vitro, relatos de casos e séries, bem como artigos que apresentassem resumos redigidos em idiomas diferentes do português, inglês e espanhol foram excluídos do estudo. Dois revisores consideraram a elegibilidade, o risco de viés dos dados analisados e a síntese qualitativa dos estudos incluídos. Foram encontradas 1.322 referências e 4 artigos atenderam a todos os critérios de inclusão e foram incluídos na análise qualitativa. Algumas consequências como necrose pulpar e reabsorção radicular têm sido destacadas e a gravidade do trauma deve ser considerada na intervenção ortodôntica em dentes previamente traumatizados. Considerações finais: Os estudos incluídos nesta revisão sugerem que dentes traumatizados podem ser tratados ortodônticamente desde que respeitado o tempo de reorganização tecidual e acompanhadas as condições pulpares e periodontais.(AU)

Morphology changes of maxillary molar distalization by clear aligner therapy / Cambios de la morfología en la distalización de molares maxilares mediante terapia con alineadores transparentes

SUMMARY: To evaluate the skeletal, dento-alveolar and soft tissue morphology changes after maxillary molar distalization by clear aligner therapy and identify the significant efficacy of molar distalization,18 patients in conformity with the inclusion criteria were selected. Pre- and post-treatment Cone Beam Computed Tomography (CBCT) were examined to measure the angular and linear parameters. All subjects were completed non-extraction clear aligner treatment by distalizing molars. A paired-t test and independent-samples t-test were performed to observe the difference between before and after treatment and the difference between the first molar and second molar respectively. P-values <0.05 were considered statistically significant. Predicted movement rate was calculated by the formula: (actual movement(mm)/planned movement(mm)) x100%. Most variables of pre- and post-treatment showed no statistical difference(P<0.05), excepting SNA angle (P<0.05) and Upper lip/E-line linear (P<0.01) due to incisor retraction. The first and second molar revealed a translation movement without significant tipping and vertical movement. Clear aligners provided a high predictability (83.44 %) of distalization the maxillary first molar, and 85.14 % of the maxillary second molar. Clear aligners can effectively achieve distal displacement of molars.

RESUMEN: Se seleccionaron 18 pacientes, de acuerdo con los criterios de inclusión, para evaluar los cambios en la morfología esquelética, dentoalveolar y de los tejidos blandos después de la distalización de los molares maxilares, mediante la terapia con alineadores transparentes e así identificar la significativa eficacia de la distalización de los molares. Se examinó a través de tomografía computarizada de haz cónico (CBCT) antes y después del tratamiento para medir los parámetros angulares y lineales. Todos los sujetos completaron el tratamiento con alineadores transparentes sin extracción mediante la distalización de los molares. Se realizó una prueba t pareada y una prueba t de muestras independientes para observar la diferencia entre antes y después del tratamiento y la diferencia entre el primer molar y el segundo molar, respectivamente. Los valores de p<0,05 se consideraron estadísticamente significativos. La tasa de movimiento prevista se calculó mediante la fórmula: (movimiento real (mm)/movimiento planificado (mm)) x 100 %. La mayoría de las variables de pre y postratamiento no mostraron diferencia estadística (P<0,05), excepto el ángulo SNA (P<0,05) y el labio superior/línea E lineal (P<0,01) debido a la retracción del incisivo. El primer y segundo molar revelaron un movimiento de traslación sin inclinación significativa y movimiento vertical. Los alineadores transparentes proporcionaron una alta previsibilidad (83,44 %) de la distalización del primer molar superior y del 85,14 % del segundo molar superior. Los alineadores transparentes pueden lograr efectivamente el desplazamiento distal de los molares.

Caracterización morfológica de caninos en premolares, un caso de anodoncia parcial de caninos maxilares / Morphological characterization of canine teeth done in first bicuspid, a maxillary canine partial anodontia case report

En este informe de caso clínico se muestra el tratamiento exitoso de un paciente con anodoncia parcial de órganos dentales 13 y 23 debido a que fueron extraídos por presentar impactación y mal pronóstico de tracción. En este artículo se presenta un paciente masculino de 29 años clase I esquelética con un perfil convexo, maloclusión de clase III, overjet disminuido, ausencia de guías funcionales, discrepancia oseodentaria positiva en arcada superior y negativa en arcada inferior. El tratamiento se realizó con extracciones de los órganos dentales 34 y 44 para nivelar las discrepancias óseo dentarias interarcadas, se llevó a cabo mediante un cierre de espacios recíproco por medio de cadenas elásticas para ambas arcadas, con lo que se logró crear un overjet y overbite adecuados. La creación de las guías caninas funcionales se consiguió mediante el cambio de morfología de los órganos dentales 14 y 24, los cuales fueron llevados a la posición de los caninos ausentes. El tiempo total de tratamiento para este paciente fue de 24 meses. Se realizaron ameloplastias positivas, la aplicación de agregados de resina para mejorar la funcionalidad y proveer salud articular. Se sugiere que ante casos de anodoncia de caninos en la arcada superior, un tratamiento favorable se puede llevar a cabo mediante el cierre de espacios, la caracterización morfológica de los caninos ausentes mediante ameloplastias positivas en premolares (AU)

This case report shows the successful treatment of a patient with partial anodontia of dental organs 13 and 23 because they have been extracted due to present impactation and poor traction prognosis. This article presents a 29-year-old male class I skeletal patient with convex profile, class III malocclusion, overjet reduction, absence of functional guidance, positive bone-teeth discrepancy in the upper arch and negative in the lower arch. The treatment was carried out with the extractions of the dental organs 34 and 44 for correcting oral dental discrepancies between upper and lower arches; it was done using reciprocal closing of spaces by using elastic chains for both arches in order to achieve a suitable overjet and overbite. The creation of the canine guides was achieved by changing the morphology of the dental organs 14 and 24, which were taken to the position of the absent canines. The total treatment timing for this patient was 24 months. Positive ameloplasties were performed by application of resin aggregates to improve functionality and provide joint health. A favorable treatment for these kinds of cases of canine anodontics in the upper arch is carried out by closing spaces and the morphological characterization of the absent canines by positive in-premolar ameloplasties (AU)

Intrusion of posterior teeth using miniplates: intrusive mechanics is not the same as intrusion force

ABSTRACT Objective: Biologically explain some of the bone mechanisms involved in the intrusion, or intrusive effect, of teeth submitted to skeletal open bite correction using four miniplates. Methods: The results of dental intrusion were measured and compared in 3D reconstructions of cone beam computed tomography scans taken before and after treatment of 20 patients with skeletal open bite, aged between 18 and 59 years. Results: The results allow deducing that the compression and traction forces biologically promoted deformation or deflection of the osteocyte network that controls bone design, and these effects involved the external and internal surfaces of the bone, with the formation of new layers, including the cervical portion of the alveolar bone crest. This helps understanding how dental intrusion occurs in intrusive mechanics, whose forces are of inclination rather than intrusion. The root resorptions caused by the use of miniplates were insignificant, due to the more homogeneous distribution of forces in the several teeth simultaneously involved. Conclusion: Imaging studies in CT scans tend to capture in details the subperiosteal and endosteal phenomena of dental intrusion - before and after the application of intrusive mechanics -, in the form of a set of modifications called dental intrusion or intrusive effect .

RESUMO Objetivo: Explicar, biologicamente, alguns dos mecanismos ósseos envolvidos na intrusão, ou efeito intrusivo, de dentes submetidos à correção da mordida aberta esquelética por meio do uso de quatro miniplacas. Métodos: Foram mensurados, em reconstruções 3D de tomografias computadorizadas de feixe cônico, os resultados da intrusão dentária, comparando-se o antes e o depois em 20 pacientes com mordida aberta esquelética, com idades entre 18 e 59 anos. Resultados: Os resultados permitem deduzir que as forças de compressão e de tração promovem, biologicamente, deformação ou deflexão da rede osteocítica controladora do design ósseo, e esses efeitos envolvem as superfícies externas e internas do osso, com formação de novas camadas, incluindo a parte cervical da crista óssea alveolar. Isso ajuda a compreender como ocorre a intrusão dentária nas mecânicas intrusivas cujas forças são de inclinação, e não de intrusão. As reabsorções radiculares promovidas pelo uso de miniplacas são insignificantes, em função da distribuição mais homogênea das forças nos vários dentes simultaneamente envolvidos. Conclusão: Os estudos imagiológicos tendem a captar, nas tomografias, cada vez mais detalhadamente os fenômenos subperiosteais e endosteais da intrusão dentária nos pacientes - antes e depois da aplicação das mecânicas intrusivas -, na forma de um conjunto de modificações que se chama intrusão dentária ou efeito intrusivo.

Ortodoncia Digital. Sistema de Alineación Mediante Placas Transparentes: caso clínico / Digital orthodontics. Alignment system using transparent plates: a clinical case

El tratamiento ortodóncico permite rehabilitar la función como también la estética facial y de la sonrisa. En muchos casos, esto puede realizarse sin la utilización de brackets. Las placas alineadoras realizan movimientos en las arcadas dentarias y las posibilidades y los resultados obtenidos cada vez son mejores. La utilización del sistema de alineación con placas permite que muchos pacientes, que no están dispuestos a utilizar brackets, encuentren una respuesta a sus problemas de oclusión (AU)

Reto multidisciplinario ante fractura vertical / Multidisciplinary challenge in a patient with a vertical fracture

Resumen Introducción: La extrusión rápida ortodóntica puede usarse como alternativa para evitar extraer una pieza fracturada que no podría ser restaurada por trauma, caries extensas, problemas periodontales (dos o tres paredes), dientes con reabsorción interna y dientes con perforaciones endodónticas. Objetivo: De este caso clínico es presentar a todos los odontólogos una solución sencilla de tratamiento integral de un paciente el cual sufrió un trauma facial, causándole una fractura vertical a nivel del tercio medio radicular del incisivo central superior derecho. Método: Mediante una extrusión ortodóntica, retratamiento endodóntico y abordaje periodontal, de manera que facilite la futura rehabilitación con corona completa. El resultado de este procedimiento se logró con mucho éxito gracias a que concluimos que se trató en forma multidisciplinaria, en donde cada especialidad actúa o interviene en un momento preciso. Conclusiones: La extrusión rápida es un procedimiento en el cual una pieza que ha sufrido una fractura radicular a nivel marginal puede ser tratada sin necesidad de realizar un alargamiento de corona comprometiendo así el nivel del hueso de la pieza.

Abstract Introduction: Rapid dental orthodontic extrusion may be used as an alternative to avoid the extraction of fractured teeth that might not be suitable for restauration because od trauma, extensive cavities, periodontal problems (two or three walls), teeth with internal resorption, or with endodontical perforations. Objective: Of this clinical case is to present to all dentists a simple solution of integral treatment of a patient who suffered trauma to his face causing a vertical fracture at the level of the middle third root of the right upper central incisor. Methods: Used in this case was through orthodontic extrusion, endodontic retreatment and periodontal approach, so as to facilitate future rehabilitation with a full crown. The result of this procedure was achieved with great success because we conclude that it was treated in a multidisciplinary way, where each specialty intervenes at a precise moment. Conclusions: Rapid extrusion is a procedure in which a tooth that shows a radicular fracture close to it´s margin may be treated without dental crown lengthening that would risk bone level.

Actualidad en ortodoncia: las micro-osteoperforaciones en la aceleración del tratamiento ortodóncico / An update in orthodontics: micro-osteoperforations for accelerating orthodontic treatment

La búsqueda por encontrar métodos para acortar la duración de los tratamientos de ortodoncia tiene un pasado reciente, un presente y un futuro. Las fuerzas ortodóncicas que se ejercen sobre la membrana periodontal producen movimientos dentarios por modificaciones histológicas y biomoleculares. El conocimiento de los procesos biológicos da lugar a implementar cambios para favorecer la aceleración de los procesos resortivos y neoformativos. El objetivo de esta publicación es hacer una breve síntesis de lo acontecido con este tema y exponer el procedimiento de las micro-osteoperforaciones (MOPs) como una opción complementaria al tratamiento de ortodoncia convencional. Aún no existe suficiente apoyo de ensayos clínicos en humanos para aseverar su éxito. Más aún, distintos autores publican conclusiones contradictorias. Es de esperar que, en breve, nuevas investigaciones contribuyan a respaldarlo o desestimarlo (AU)

The quest to find methods to shorten the duration of orthodontic treatments has a recent past, a present, and a future. Orthodontic forces exerted on the periodontal membrane produce tooth movements by histological and biomolecular modifications. Knowledge of biological processes results in changes to promote the acceleration of spring and neoformative processes. The objective of this publication is to make a brief synthesis of what happened with this topic and expose the micro-osteoperforations (MOPs) procedure as a complementary option to conventional orthodontic treatment. There is not yet enough support from human clinical trials to assert its success. Moreover, different authors publish conflicting conclusions. It is to be expected that, shortly, further investigations will help to support or dismiss it (AU)

Relationship between the polymorphism in the interleukin 1-β and the treatment time of patients subjected to a modified piezocision technique / Relación entre el polimorfismo en la interleucina 1-β y el tiempo de tratamiento de pacientes sometidos a una técnica de piezocisión modificada

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.

Hyalinization and Molecular Pathways Involved in Orthodontic Tooth Movement: A Systematic Review and Meta-Analysis

Abstract Objective: To systematically review the hyalinization of experimental tooth movement in humans and animals. Material and Methods: The electronic databases of MEDLINE, PubMed, Cochrane Library, Embase, Institute for Scientific Information, and Google Scholar were searched for performing a systematic review of the related literature published until 2019. Moreover, Endnote X9 software was utilized to manage electronic titles. The searches were fulfilled using keywords of "hyalinization," "orthodontic tooth movement" OR "OTM" AND "periodontal ligament" OR "PDL," "molecular pathways," AND "mechanical cell." Therefore, this systematic review was conducted based on the key consideration of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Results: Forces ranged between 2.3 and 50 CN had been applied. According to the research design, incisors had been included in two experiments, whereas maxillary molars had been displaced by tipping forces in another rat examination. However, a majority of investigations had stated that hyalinization had firstly appeared within the first 24 hours. Moreover, the amount of prostaglandin-end peroxide synthase 2 (PTGS2) had been positively related to force term and size utilizing Western blotching. As PTGS2 had been included in the prostaglandin E2 (PGE2) metabolism, the up-regulation of PTGS2 gene expression could be connected with that of PGE2 emission. Conclusion: Gene expression in connection with force term and size and also the first signalling pathways were recognized utilizing protein-protein interactions (PPIs).

Use of Mini-Implant Anchorage For Second Molar Mesialization: Comprehensive Approach For Treatment Efficiency Analysis

Abstract Objective: To approbate the complex approach for assessment of second molar mesialization outcomes with the use of orthodontic mini-implants. Material and Methods: The sample consisted of 62 patients, divided into study (n=32) and control group (n=30). Mesialization procedure in the study group was conducted with the use of braces system and orthodontic mini-implants as additional anchorage devices, while in control group mesialization was provided only with the use of the brace system. Dynamic registration of bone level changes and the entire range of tooth movement were carried out on digital orthopantomograms obtained with the use of Planmeca ProMax 2D. Results: Findings of orthopantomographic (OPG) analysis have shown that cases of second molar mesialization with the use of mini-implants as temporary anchorage characterized with more stable conditions of bone levels around displaced teeth compare to cases, where mesialization was provided only with the use of braces systems without any additional anchorage. The terms of treatment in the study group with the use of dental mini-implants as the anchorage was reduced by 8.8 ± 0.12 months compared to the control group (p<0.05). Conclusion: The use of orthodontic mini-implants as anchorage constructions during the mesialization of the mandibular second molars contributes to the reduction of treatment duration and support the more prognostic movement of teeth, that does not provoke significant pathological changes in the levels of the surrounded alveolar ridge and minimize the risk of associated periodontal complication occurrence.

Atypical Extraction of Maxillary Central Incisor for the Correction of Angle Class II Malocclusion / Extracción Atípica de Incisivo Central Maxilar en la Corrección de la Maloclusión de Angle Clase II

ABSTRACT: This case describes the treatment of Class II malocclusion in a patient missing one of the maxillary central incisors due to traumatic impaction. The treatment approach consisted in the extraction of the remaining maxillary central incisor, followed by diastema closure and re-anatomization of lateral incisors into central incisors. The results obtained were considered satisfactory concerning occlusal, aesthetic and functional aspects. This therapeutic approach may be used as an alternative for similar cases.

RESUMEN: Este caso clínico describe el tratamiento de la mala oclusión de Clase II en un paciente con ausencia de uno de los incisivos centrales superiores debido a impactación. El abordaje del tratamiento consistió en la extracción de este elemento dental y del otro incisivo central, seguido del cierre de los diastemas y reanatomización de los incisivos laterales en incisivos centrales. Los resultados obtenidos fueron considerados satisfactorios con relación a los aspectos oclusales, estéticos y funcionales. Así, esta planificación se puede utilizar como una nueva alternativa de abordaje terapéutico para estos casos.

Comparing the Clinical Success Rate of Self-Drilling and Self-Tapping Mini-screws in the Retraction of Maxillary Anterior Teeth

Objective: To compare the success of self-drilling and self-tapping methods in the retraction of maxillary anterior teeth. Material and Methods: The study was conducted in 57 subjects with Cl II malocclusion who needed to be treated with extraction of four maxillary teeth. The selftapping method was used on the left side and the self-drilling method was used on the right side. Then, the pain rate of each method was recorded by the numerical rating scale (NRS). Statistical analysis was done by t-test and Chi-square test. The significance level in this study was considered at p-value<0.05. Results: Considering the clinical mobility as the failure, the success of treatment was equal in both methods and was 93%. The inflammation around the mini-screws was 8.8%. A significant relationship was found between the variables inflammation and success (p<0.05). The mean pain was 2.47 but there was no significant difference between the two methods in terms of pain score (p>0.05). There was a significant difference between the groups (p=0.03). The pain was significantly higher in the female. Conclusion: There is no difference between self-drilling and self-tapping methods in terms of success. Comparison of the pain between two genders according to the replantation method showed a significant difference in pain sensation between two genders. The pain sensation mean in female group was greater than male group.

Three-dimensional assessment of external apical root resorption after maxillary posterior teeth intrusion with miniscrews in anterior open bite patients

ABSTRACT Objective: The objective of this study was to assess the external apical root resorption (EARR) of the maxillary posterior teeth after intrusion with miniscrews. Methods: Fifteen patients (13 females and 2 males) with age ranging from 14.5 to 22 years (mean 18.1 ±2.03 years) were selected to participate in this study. All patients presented with anterior open bite of 3 mm or more. An intrusion force of 300 g was applied on each side to intrude the maxillary posterior teeth. Cone beam computed tomography (CBCT) scans were taken pretreatment and post-intrusion and were analyzed to evaluate the EARR. Results: The maxillary posterior teeth were intruded in average 2.79 ± 0.46 mm (p< 0.001) in 5.1 ± 1.3 months, and all examined roots showed statistically significant EARR (p< 0.05) with an average of 0.55 mm, except the distobuccal root of the left first permanent molars and both the palatal and buccal roots of left first premolars, which showed no statistically significant changes. Conclusions: The evaluated teeth presented statistically significant EARR, but clinically, due to the small magnitude, it was not considered significant. Moreover, the CBCT provided a good visualization of all roots in all three planes, and it was effective in detecting minimal degrees of EARR.

RESUMO Objetivo: o objetivo desse estudo foi verificar a existência de reabsorção radicular apical externa (RRAE) em dentes posterossuperiores após intrusão ancorada em mini-implantes. Métodos: quinze pacientes (13 mulheres e 2 homens) com a idade variando entre 14,5 e 22 anos (média de 18,1 ± 2,03 anos) foram selecionados para participar desse estudo. Todos os pacientes possuíam mordida aberta anterior de 3mm ou mais. Uma força de 300 gramas foi aplicada em cada lado para intruir os dentes posterossuperiores. Tomografias computadorizadas de feixe cônico (TCFC), adquiridas antes do tratamento e após a intrusão, foram comparadas para se avaliar a RRAE. Resultados: os dentes posterossuperiores foram intruídos em média 2,70 ± 0,46 mm (p< 0,001) em 5,1 ± 1,3 meses, e todas as raízes examinadas mostraram RRAE estatisticamente significativa (p< 0,05), com média de 0,55 mm, exceto pela raiz distovestibular dos primeiros molares permanentes esquerdos, e pelas raízes palatina e vestibular dos primeiros pré-molares esquerdos, que não apresentaram mudanças estatisticamente significativas. Conclusões: os dentes avaliados apresentaram RRAE estatisticamente significativa, a qual, porém, não foi considerada clinicamente significativa, devido à sua reduzida magnitude. Além disso, a TCFC possibilitou uma boa visualização de todas as raízes nos três planos espaciais, e foi eficaz para detecção de níveis mínimos de RRAE.

Macroscopic and microscopic evaluation of flapless alveolar perforations on experimental tooth movement

Abstract Objective: The aim of this study was to evaluate a flapless surgical technique as an alternative to traditional alveolar corticotomy used to accelerate orthodontic tooth movement (OTM). Methods: To induce OTM in Wistar rats, 40 cN of orthodontic force were applied to the maxillary left first molars. Forty rats were distributed into control groups (CG1, CG3, CG7 and CG14) and experimental groups (n= 5), in which alveolar perforations were made using a spear-shaped guide bur (EG1, EG3, EG7, EG14). Euthanasia dates were set at 1, 3, 7 and 14 days, respectively, after tooth movement began. The amount of OTM was measured with a caliper, and osteoclasts present in the periodontal ligament of the mesial root of the moved tooth were counted by means of histological evaluation (tartrate-resistant acid phosphatase staining, TRAP). Results: Although there was no difference in the amount of OTM within subgroups of corresponding experimental periods (p> 0.05), when EG14 and CG14 were compared, a larger number of osteoclasts was counted in the experimental group (p< 0.00). Conclusion: The authors concluded that flapless cortical alveolar perforations led to more intense osteoclastic activity on the fourteenth day; nevertheless, no evidence of accelerated OTM could be noted.

Resumo Objetivo: o objetivo do presente estudo foi avaliar a técnica cirúrgica sem retalho como alternativa à tradicional corticotomia alveolar utilizada para acelerar o movimento dentário experimental. Métodos: para induzir a movimentação dentária experimental em ratos Wistar, foram aplicados 40 cN de força ortodôntica aos primeiros molares superiores esquerdos. Quarenta ratos foram distribuídos nos grupos (n = 5) controles (GC1, GC3, GC7 e GC14) e experimentais (GE1, GE3, GE7, GE14), nos quais foram realizadas perfurações alveolares com uma ponta lança. As datas de eutanásia foram estabelecidas em 1, 3, 7 e 14 dias, respectivamente, após o início do movimento dentário. A quantidade de deslocamento dentário foi medida com um paquímetro e os osteoclastos presentes no ligamento periodontal da raiz mesial do dente movimentado foram contados por meio de avaliação histológica (coloração por fosfatase ácida resistente ao tartarato, TRAP). Resultados: embora não tenha havido diferença na quantidade de deslocamento dentário dentro dos subgrupos dos períodos experimentais correspondentes (p> 0,05), quando GC14 e GE14 foram comparados, um número maior de osteoclastos foi contado no grupo experimental (p< 0,00). Conclusão: os autores concluíram que as perfurações alveolares corticais sem retalho levaram a uma atividade osteoclástica mais intensa no décimo quarto dia; entretanto, nenhuma evidência de movimento dentário acelerado pôde ser notada.

A CBCT evaluation of molar uprighting by conventional versus microimplant-assisted methods: an in-vivo study

ABSTRACT Objective: The aim of this prospective study was to compare the three-dimensional effects of the conventional helical uprighting spring (CA) and the mini-implant assisted helical uprighting spring (MIA), using CBCT scans. Methods: Twenty patients with mesially tipped second mandibular molars were divided into two groups: CA group, in which 10 patients were treated using a conventional helical uprighting spring with conventional anchorage; and MIA group, in which 10 patients were treated using a mini-implant supported uprighting spring. Molar uprighting was observed in both groups for a period of four months. Two standardized 11×5-cm CBCT sections of the mandible were taken, being one prior to uprighting and one at the end of the four month follow-up. Statistical analyses at the beginning of treatment and after a 4 month follow-up were performed, with a significance level of p< 0.05. Results: The mean amount of change in mesiodistal angulation in the MIA group was 8.53 ± 2.13o (p< 0.001) and in the CA group was 9.8 ± 0.5o (p< 0 .001). Statistically significant differences were found between the two groups with regard to buccolingual inclination of canine, first and second premolars (p< 0.05), second molar (p< 0.001) and extrusion of second molar (p< 0.05). Conclusions: The mean amount of change in the mesial angulation of the second molar in the CA as well as the MIA groups was similar. MIA, which used mini-implant as a source of anchorage, was more effective in preventing movement of the anchorage teeth as well as preventing extrusion of the second molar in the vertical plane, when compared to the CA group, which used dental units as a source of anchorage.

RESUMO Objetivo: o objetivo deste estudo prospectivo foi comparar, usando imagens de TCFC, os efeitos tridimensionais da mola convencional de verticalização (CA) e da mola de verticalização com ancoragem em mini-implantes (MIA). Métodos: vinte pacientes com segundos molares inferiores inclinados mesialmente foram divididos em dois grupos: grupo CA, no qual 10 pacientes foram tratados usando mola helicoidal de verticalização com ancoragem convencional; e grupo MIA, com 10 pacientes tratados usando mola de verticalização ancorada em mini-implantes. A verticalização dos molares foi observada nos dois grupos por um período de quatro meses. Foram obtidas duas secções tomográficas da mandíbula, com dimensões padronizadas de 11 x 5 cm, uma antes da verticalização e outra ao fim dos quatro meses de acompanhamento. As análises estatísticas ao início do tratamento e após os quatro meses de acompanhamento foram realizadas a um nível de significância de p< 0,05. Resultados: a média das alterações na angulação mesiodistal do grupo MIA foi de 8,53 ± 2,13o (p< 0,001), e do grupo CA foi de 9,8 ± 0,5o (p< 0,001). Diferenças estatisticamente significativas foram encontradas entre os dois grupos em relação à inclinação vestibulolingual do canino, do primeiro e segundo pré-molares (p< 0,05) e do segundo molar (p< 0,001), bem como para a extrusão do segundo molar (p< 0,05). Conclusões: a alteração média na angulação mesial do segundo molar nos grupos CA e MIA foi semelhante. O método MIA, que usou mini-implantes como ancoragem, foi mais efetivo na prevenção da movimentação dos dentes de ancoragem, bem como na prevenção da extrusão do segundo molar no plano vertical, quando comparado com o grupo CA, em que dentes foram usados como fonte de ancoragem.

Twenty-year clinical experience with fixed functional appliances

ABSTRACT Introduction: Considering the large number of fixed functional appliances, choosing the best device for your patient is not an easy task. Objective: To describe the development of fixed functional appliances as well as our 20-year experience working with them. Methods: Fixed functional appliances are grouped into flexible, rigid and hybrid. They are different appliances, whose action is described here. Four clinical cases will be reported with a view to illustrating the different appliances. Conclusions: Rigid fixed functional appliances provide better skeletal results than flexible and hybrid ones. Flexible and hybrid appliances have similar effects to those produced by Class II elastics. They ultimately correct Class II with dentoalveolar changes. From a biomechanical standpoint, fixed functional appliances are more recommended to treat Class II in dolichofacial patients, in comparison to Class II elastics.

RESUMO Introdução: considerando-se o grande número de aparelhos propulsores mandibulares, não é uma tarefa fácil escolher o melhor deles para o seu paciente. Objetivo: descrever o desenvolvimento desses aparelhos e a experiência clínica de vinte anos dos autores na sua utilização. Métodos: os aparelhos funcionais fixos aqui apresentados foram classificados em flexíveis, rígidos e híbridos, e o modo de ação de cada um deles foi descrito e ilustrado por meio de quatro casos clínicos. Conclusões: os aparelhos propulsores rígidos fornecem mais resultados esqueléticos do que os flexíveis e os híbridos. Esses últimos têm efeito semelhante ao uso de elásticos com direção de Classe II e, basicamente, corrigem a má oclusão de Classe II com alterações dentoalveolares. Do ponto de vista biomecânico, os propulsores fixos estão mais indicados para tratar a Classe II em pacientes dolicofaciais do que os elásticos de Classe II.

Use of Artificial Neuron Network to Predict Dental Arch Form

Objective: To develop diagnostic reference for arch form using Artificial Neuron Network (ANN) from tooth size and arch dimension variables on scanned-dental cast from patients with class I malocclusion treated orthodontically. Material and Methods: One hundred and ninety pairs of dental cast pre-post orthodontic treatment gathered from Orthodontic clinics were scanned and then all dimension variables were measured using Image Tool (gender, tooth size and arch dimension). The multivariate data were analyzed statistically using Stata (Lakeway Drive, College Station, Texas USA). The statistic results were compiled to build the neuron network software for analyzing arch form. Results: Gender and all variables from pre-treatment do not influence arch form. Intercanine width, canine depth, intermolar width, and molar depth are variables that influence arch form. The result of the statistical analyses can be used to develop software based on artificial neural network. Output program is the arch form, such as oval, square or tapered. The software can describe arch form with the accuracy of 76.31%. Conclusion: A software using Artificial Neuron Network to describe arch form can be used for diagnostic reference to Class I malocclusion.

Extruded upper first molar intrusion: Comparison between unilateral and bilateral miniscrew anchorage

ABSTRACT Objective: The aim of his study was to evaluate the stress on tooth and alveolar bone caused by orthodontic intrusion forces in a supraerupted upper molar, by using a three-dimensional Finite Element Method (FEM). Methods: A superior maxillary segment was modeled in the software SolidWorks 2010 (SolidWorks Corporation, Waltham, MA, USA) containing: cortical and cancellous bone, supraerupted first molar, periodontal tissue and orthodontic components. A finite element model has simulated intrusion forces of 4N onto a tooth, directed to different mini-screw locations. Three different intrusion mechanics vectors were simulated: anchoring on a buccal mini-implant; anchoring on a palatal mini-implant and the association of both anchorage systems. All analyses were performed considering the minimum principal stress and total deformation. Qualitative analyses exhibited stress distribution by color maps. Quantitative analysis was performed with a specific software for reading and solving numerical equations (ANSYS Workbench 14, Ansys, Canonsburg, Pennsylvania, USA). Results: Intrusion forces applied from both sides (buccal and palatal) resulted in a more homogeneous stress distribution; no high peak of stress was detected and it has allowed a vertical resultant movement. Buccal or palatal single-sided forces resulted in concentrated stress zones with higher values and tooth tipping to respective force side. Conclusion: Unilateral forces promoted higher stress in root apex and higher dental tipping. The bilateral forces promoted better distribution without evidence of dental tipping. Bilateral intrusion technique suggested lower probability of root apex resorption.

RESUMO Objetivos: o presente estudo teve como objetivo avaliar, por meio da Análise de Elementos Finitos, as tensões geradas por forças ortodônticas intrusivas em um molar superior e no osso alveolar circundante. Métodos: um segmento maxilar foi modelado no software SolidWorks 2010 (SolidWorks Corporation, Waltham, MA, EUA), contendo: osso cortical e medular, primeiro molar extruído, tecido periodontal e acessórios ortodônticos. Um modelo de elementos finitos simulou forças intrusivas de 4 N no elemento dentário, aplicadas a partir de mini-implantes em localizações distintas. Três diferentes vetores para mecânica de intrusão foram simulados: ancoragem em mini-implante vestibular, ancoragem em mini-implante palatino ou a associação de ambas. Todas as análises foram realizadas em termos de tensão mínima principal e deformação total. A análise qualitativa foi feita por meio do mapeamento da distribuição das tensões em gradiente de cores. A análise quantitativa foi feita em software específico para leitura e resolução de equações numéricas (ANSYS Workbench 14, Ansys, Canonsburg, Pennsylvania, EUA). Resultados: as forças intrusivas aplicadas simultaneamente nos dois lados (vestibular e palatino) resultaram em uma distribuição mais homogênea das tensões geradas, sem zonas de acúmulo de tensão e com uma resultante vertical para a movimentação intrusiva. As forças aplicadas somente em um lado, vestibular ou palatino, resultaram em zonas de concentração de tensão, com maiores valores, e na inclinação do elemento dentário para o lado em que a força foi aplicada. Conclusão: as forças unilaterais promoveram maior tensão no ápice radicular e maiores inclinações do elemento dentário. Já as forças bilaterais promoveram melhor distribuição das tensões e não resultaram em inclinação do elemento dentário. Assim, as forças intrusivas ancoradas bilateralmente apresentam menor probabilidade de reabsorção do ápice radicular.

Effect of acute administration of nicotine and ethanol on tooth movement in rats

Abstract The aim of this study was to evaluate the effect of acute administration of nicotine and ethanol on tooth movement in rats. Two hundred rats were divided into eight groups: S: saline; N: nicotine; E: ethanol; NE: nicotine and ethanol; SM: saline with tooth movement; NM: nicotine with tooth movement; EM: ethanol with tooth movement; and NEM: nicotine and ethanol with tooth movement. All the solutions were applied for 32, 44, or 58 days, according to the subgroup. Orthodontic movement (25 cN) was initiated 30 days after solution administration in the groups with tooth movement. The rats were euthanized 2, 14, or 28 days after initiation of tooth movement. Tooth sections were stained using picrosirius and tartrate-resistant acid phosphatase (TRAP). The data were compared by ANOVA using Tukey's HSD and Games-Howell. On day 28 of tooth movement, the NEM group had a lower percentage of type I collagen compared to the SM group (p = 0.0448), and the S group had a higher number of osteoclasts/μm2 compared to the N group (p = 0.0405). Nicotine and ethanol did not affect the tooth movement rate, regardless of induction of orthodontic movement. Nicotine influenced the number of osteoclasts by decreasing their quantity when dental movement was not induced. When nicotine was associated with ethanol, it interfered in the maturation of collagen fibers during orthodontic movement.