RESUMO

This study aimed to describe the changes produced on the occlusal plane (OP), the mandibular position and the dentoalveolar compensations of patients with distalization of the maxillary/mandibular arch assisted by mini-screws (MS). A descriptive case-series study was performed using the digital lateral cephalograms (DLC) of nine patients who underwent orthodontic treatment and required the use of MS for a complete distalization of the maxillary/mandibular arch. Records were collected at three different times (T1-T2-T3) and digitally analyzed (variables: Skeletal diagnosis; maxillary occlusal plane; position of the maxilla/mandible; and dentoalveolar changes of the distalization arch tracing the longitudinal axis of incisors/molars regarding the palatal/mandibular plane). Findings show that the OP varied from T1-T2-T3 in all cases, indicating its stepping or flattening. ODI, APDI, SNA, SNB, and ANB changed minimally in all cases, without variations in the mandibular position or in the skeletal diagnosis. Dentoalveolar measurements also showed differences between T1-T2-T3. In summary, conventional orthodontic treatment modified the OP during the first phase of treatment. Moreover, the distalization mechanics with MS changed the OP and produced dentoalveolar changes, mainly in the inclination of incisors and molars. Other measures considered in the study did not change substantially.

RESUMO

PURPOSE: This two-arm parallel randomized controlled trial aimed to evaluate and compare periodontal changes due to rapid maxillary expansion (RME) using tooth-bone-borne and tooth-borne devices in growing patients via clinical examinations and cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Forty-two eligible patients (aged 11-14 years; transverse maxillary deficiency, posterior crossbite) were screened and divided into two groups based on the treatment received (randomization was performed using computer-generated numeric sequences): hybrid hyrax tooth-bone-borne group (TBB) and hyrax tooth-borne group (TB). The primary outcome was the change in cortical bone thickness (by CBCT). In addition, the clinical attachment level (CAL), gingival recession, and bleeding were assessed. Both examinations were performed before and 3 months after the activation phase. Intergroup comparisons were performed using analysis of covariance (ANCOVA; P < 0.05). RESULTS: Twenty-one patients (12 girls and 9 boys; mean initial age, 13.3 years) were included in the TBB group and 21 (5 girls and 16 boys; mean initial age, 13.2 years) were included in the TB group. The TB group exhibited a decrease in buccal bone thickness in the first premolars and first molars at all three evaluated levels. Specifically, tooth 14 at 3 mm from the enamel-cement junction showed a significant width reduction (0.7 mm; p < 0.001), accompanied by a notable increase in palatal cortical thickness at 6 mm of enamel-cement junction (1.13 mm; p < 0.001). CONCLUSIONS: RME resulted in buccal bone thickness reduction at the first premolar with hyrax treatment. In the molar region, both devices resulted in cortical bone alterations that were less pronounced in the TBB group.

RESUMO

OBJECTIVES: To synthesise the dentoalveolar, periodontal and skeletal changes that occur when using maxillary expansion techniques assisted by temporary anchorage devices compared to conventional protocols. METHODS: Five databases and grey literature were consulted, up to December 2023, focusing on intervention designs and excluding other type of studies. The quality assessment was conducted by using the adaptation for orthodontics of the CONSORT statement, the guidelines for reporting non-randomised studies, the RoB-2 tool, and the ROBINS-I tool. A descriptive summary and meta-analysis using RevMan 5.4 were performed. RESULTS: Nine clinical trials were included (n=377 patients, mean age 13.2±0.6) with a diagnosis of transverse maxillary deficiency. The analysed studies showed qualitative dentoalveolar and periodontal changes after expansion, which were greater on the maxillary first premolars in tooth-borne appliances. Meta-analyses for some effects were included from two studies (n=64); patients who used tooth-borne appliances had greater effects of buccal intercoronal width between the premolars with statistically significant differences (Std Mean difference 2.34; 95% CI: 0.04-4.65 p=0.05). Conversely, those patients who used bone-borne or hybrid appliances had greater effects of buccal intercoronal width between molars with statistically significant differences (Std Mean difference -0.64; 95% CI: -1.38-0.10; p=0.09). CONCLUSIONS: According to the studies analysed, all measurements increased in the intervention groups after expansion. Quantitative analyses show different findings at dentoalveolar level when tooth-borne, bone-borne or hybrid appliances are considered. Nevertheless, the results should be taken with caution due to the heterogeneity of the studies. The protocol was registered at PROSPERO (CRD42021283170), with no funding to report.

Assuntos

RESUMO

El manejo del anclaje en los tratamientos de ortodoncia ha sido un reto constante, por lo que la utilización de miniplacas aparece como un rescate a esta interrogante. Determinar las diferencias morfológicas en la zona de inserción de miniplacas ortodóncicas en las regiones anterior y posterior mandibular, comparandolas entre edad, sexo, biotipo y clase esqueletal. Se estudiaron 40 registros de cone-beam de pacientes y se realizaron mediciones de grosor del hueso, donde se identificaron los sitios que permitan posicionar una miniplaca y fueron comparados entre sexo, grupos etarios, biotipo y clase esqueletal. Se observó diferencias significativas entre hombres y mujeres a nivel anterior mandibular, en los hombres se observaron mayores grosores óseos y corticales. No se observaron diferencias significativas entre pacientes adultos y jóvenes a nivel anterior mandibular, pero sí hubo diferencias a nivel mandibular posterior. La zona 3 mm debajo del 2do molar no es una zona confiable para la inserción de mini placas, ya que muchos de los pacientes no presentaban hueso en esa zona. Las miniplacas son un recurso seguro de anclaje las cuales deben ser adaptadas a cada paciente.

The anchorage management in orthodontic treatments has been a constant challenge, the use of miniplates may be a viable solution to this query. The objective of this study was to determine the morphological differences in the area of insertion of orthodontic miniplates in the anterior and posterior mandibular regions, comparing them between age, sex, biotype and skeletal class. In this analysis 40 cone-beam records of patients were studied, bone thickness measurements were carried out, the sites that allowed the positioning of a miniplate were identified and compared between sex, age groups, biotype and skeletal class. Significant differences were observed between men and women at the anterior mandibular level, in men greater bone and cortical thicknesses were observed. No significant differences were observed between adult and young patients at the anterior mandibular level, but there were differences at the posterior mandibular level. The area 3 mm below the 2nd molar was not a reliable area for the insertion of mini plates, since many of the patients had no bone in that area. Miniplates are a safe anchoring resource which must be adapted to each patient.

RESUMO

OBJECTIVE: To evaluate the efficacy of microchips and 3D microsensors in the measurement of orthodontic forces. METHODS: Through September 2023, comprehensive searches were conducted on PubMed/MEDLINE, SCOPUS and SCIELO without restrictions. RESULTS: After removing duplicate entries and applying the eligibility criteria, 23 studies were included for analysis. All the studies were conducted in vitro, and slightly more than half of them were centred on evaluating orthodontic forces exerted by aligners. Eight utilized microchips as measurement tools, while the remaining studies made use of 3D microsensors for their assessments. In the context of fixed appliances, key findings included a high level of agreement in 3-dimensional orthodontic force detection between simulation results and actual applied forces. Incorporating critical force-moment combinations during smart bracket calibration reduced measurement errors for most components. Translational tooth movement revealed a moment-to-force ratio, aligning with the bracket's centre of resistance. The primary findings in relation to aligners revealed several significant factors affecting the forces exerted by them. Notably, the foil thickness and staging were found to have a considerable impact on these forces, with optimal force transmission occurring at a layer height of 150 µm. Furthermore, the type of material used in 3D-printing aligners influenced the force levels, with attachments proving effective in generating extrusive forces. Deliberate adjustments in aligner thickness were observed to alter the forces and moments generated. CONCLUSIONS: Microchips and 3D sensors provide precise and quantitative measurements of orthodontic forces in in vitro studies, enabling accurate monitoring and control of tooth movement.

RESUMO

The purpose of this article was to describe a simple graphical driven method for determining the necessary two-vector mechanics (TVM) as an alternative solution to the ideal or single force. In orthodontics, some tooth movements are difficult to achieve, mainly because of the impossibility of getting the point of application for the necessary force system. Given two points in biomechanically accessible areas, adding together two vectors applied to those points will result in an equivalent force system. The method was developed based on previous research, 3,880 hypothetical cases were analyzed to determine the trends between the resulting forces and their relative locations. A graphical driven TVM method (GTVM) for establishing the necessary TVM is presented in a manner that combine different procedures from the traditional method that simplify the analysis and may allow the user to perform more complex orthodontic cases making easier to compare systems of force equivalents.

Assuntos

RESUMO

A expansão rápida da maxila (ERM) representa o procedimento gold-standard para correção da deficiência transversal do arco dentário superior. Porém, a idade é fator limitante para o sucesso da ERM convencional. Recentemente, a expansão rápida da maxila assistida por mini-implantes (MARPE) ampliou o limite de idade para separação da sutura palatina mediana (SPM), permitindo a correção minimamente invasiva da atresia maxilar, em pacientes adultos. O objetivo deste artigo foi relatar um caso clínico de um paciente adulto com mordida cruzada posterior tratado com MARPE, avaliar os efeitos transversais, o reparo da sutura palatina mediana (SPM) e a estabilidade da expansão após 8 meses de contenção. Paciente de sexo masculino, de 25 anos de idade, apresentava-se com mordida cruzada posterior bilateral, má oclusão de Classe III bilateral e estágio de maturação da SPM avançado. Foi indicado o tratamento com MARPE com 4 parafusos, posicionados parassuturalmente, seguido de tratamento compensatório para Classe III. Após a fase ativa da expansão o aparelho foi mantido por 12 meses como contenção. Após os 6 meses foram removidas as hastes do expansor e foi instalado o aparelho fixo, com uso de elásticos intermaxilares O reparo completo da SPM foi observada após um período de 12 meses de contenção. Após a ortodontia corretiva, uma adequada relação oclusal de molar Classe I foi alcançada (AU)

Rapid palatal expansion (RPE) represents the gold-standard procedure for correcting transverse maxillary dental arch deficiency. However, age is a limiting factor for the success of conventional RPE. Recently, mini-implant-assisted rapid palatal expansion (MARPE) has extended the age limit for midpalatal suture (MPS) separation, allowing for minimally invasive correction of maxillary atresia in adult patients. The aim of this article was to report a clinical case of an adult patient with posterior crossbite treated with MARPE, to evaluate the cross-sectional effects, midpalatal suture (MPS) repair and expansion stability after 8 months of retention. A 25-year-old male patient presented with bilateral posterior crossbite, bilateral Class III malocclusion, and advanced PMS maturation stage. Treatment with MARPE with 4 screws, positioned parasuturally, was indicated, followed by compensatory treatment for Class III. After the active phase of expansion, the appliance was kept for 12 months as a retainer. After 6 months, the expander rods were removed and the fixed appliance was installed using inter maxillary elastics. Complete PMS repair was observed after a period of 12 months of retention. After corrective orthodontics, an adequate Class I molar occlusal relationship was achieved (AU)

Assuntos

RESUMO

Orthodontic miniscrews are used to achieve absolute anchorage. Their insertion technique is simple but must be precise to avoid intra- and postoperative complications. This study aimed to review the literature on the role of digital technology in the precise placement of miniscrews and to describe the different stages of the insertion guide manufacturing chain. The databases used were PubMed, Science Direct, and Google Scholar, including the following English descriptors: "Orthodontic Anchorage Procedures," "Cone Beam Computed Tomography." Digital technology improves the accuracy of miniscrew placement by using 3D imaging to assess the quantity and quality of bone and the proximity of anatomical structures in the area to be implanted. By combining 3D imaging with the new techniques of 3D printing and virtual planning, the orthodontist can obtain a personalized placement guide for the patient using computer-aided design and manufacturing techniques. A digitally-assisted miniscrew insertion system is a promising technique for precise and safe miniscrew insertion but cannot be used routinely. Therefore, large-scale studies are needed to map miniscrew insertion in different areas, considering ethnicity, gender, and different anatomical characteristics.

RESUMO

Atualmente é evidente a demanda contínua por padrões de beleza, cada vez mais impecáveis, um sorriso alinhado e harmônico com dentes brancos para se sorrir com confiança. O tratamento odontológico interdisciplinar tem como intuito proporcionar uma boa saúde periodontal, restabelecer a estética e a função do sistema estomatognático. Objetivo: apresentar um relato de caso clínico envolvendo harmonização do sorriso como cirurgia plástica periodontal para alinhamento da margem gengival na região anterior e restaurações diretas em resina composta após a finalização do tratamento ortodôntico, evidenciando a importância da abordagem conservadora e multidisciplinar no âmbito do tratamento estético. Relato de caso: Realizamos o tratamento ortodôntico com aparelho autoligado cerâmico para alinhamento do arco dental e intrusão do elemento 13, em sequência executamos um recorte gengival nos elementos 12 e 22, clareamento dental associado após 15 dias, subsequentemente, reanatomização dentária no elemento 44 para que o elemento 13 não voltasse a extruir pela falta de contato oclusal, e por fim, remodelação dental fazendo uso de resina composta nos elementos 12, 21 e 22 devido a manchas de hipocalcificação dental. Conclusão: Contudo, a estética bucal tem a capacidade de possibilitar a melhoria na autoestima, devolvendo à função, proporcionando satisfação e bem-estar ao indivíduo, enaltecendo o sorriso.

Currently, the continuous demand for increasingly impeccable beauty standards is evident, an aligned and harmonic smile with white teeth to smile with confidence. Interdisciplinary dental treatment aims to provide good periodontal health, restore the aesthetics and function of the stomatognathic system. Objective: to present a clinical case report involving smile harmonization as periodontal plastic surgery for aligning the gingival margin in the anterior region and direct composite resin restorations after completion of orthodontic treatment, highlighting the importance of a conservative and multidisciplinary approach in the field of aesthetic treatment . Case report: We performed orthodontic treatment with a self-ligating ceramic appliance for aligning the dental arch and intruding element 13, then performed a gingival cutout on elements 12 and 22, associated tooth whitening after 15 days, subsequently, dental reanatomization on element 44 to that element 13 would not extrude again due to the lack of occlusal contact, and finally, dental remodeling using composite resin in elements 12, 21 and 22 due to dental hypocalcification stains. Conclusion: However, oral aesthetics has the ability to improve self-esteem, returning to function, providing satisfaction and well-being to the individual, enhancing the smile.

Assuntos

RESUMO

OBJECTIVE: To compare two methods of maxillary molar distalisation with skeletal anchorage using finite element analysis (FEA). METHODS: Two digitised models were created: the miniscrew-anchored distaliser, which consisted of a distalisation method anchored in a buccal miniscrew between the first molar and second premolar (Model 1), and the miniscrew-anchored palatal appliance, which consisted of a distalisation method anchored in a miniscrew on the anterior region of the palate (Model 2). FEA was used to simulate both methods, assessing teeth displacements and stress concentration. RESULTS: The miniscrew-anchored distaliser showed greater buccal than distal displacement of the first molar, while the opposite was observed in the miniscrew-anchored palatal appliance. The second molar responded similarly in the transverse and anteroposterior perspectives with both appliances. Greater displacements were observed at crown level than in apical regions. Greater stress concentration was observed at the buccal and cervical regions of the crown in the miniscrew-anchored distaliser and the palatal and cervical regions in the palatal appliance. The stress progressively spread in the buccal side of the alveolar bone for the miniscrew-anchored distaliser and in the palatal root and alveolar bone for the palatal appliance. CONCLUSION: FEA assumes that both appliances would promote maxillary molar distalisation. A skeletally anchored palatal distalisation force seems to provide a greater molar bodily movement with less undesirable effects. Greater stress is expected at the crown and cervical regions during distalisation, and the stress concentration in the roots and alveolar bone depends directly on the region the force was applied.

Assuntos

RESUMO

The purpose of this research was the tomographic evaluation of the Mandibular Buccal Shelf (MBS) in orthodontic patients with different vertical growth pattern. An observational, descriptive, cross-sectional and retrospective study was conducted. Tomographic images of patients aged 14 to 40 years were observed and a database was formed with those that met the inclusion criteria. The sample size was 10 for each group according to vertical growth pattern (hypodivergent, normodivergent and hyperdivergent). Then four zones of frequent insertion of extralveolar mini-screws were selected in the MBS, taking as a reference the mesial and distal roots of the first and second mandibular molar. When comparing the characteristics of MBS between vertical growth patterns, between sexes and hemiarchs, no statistically significant differences were found. However, when the characteristics of MBS were compared according to the reference root, it was found that there were statistically significant differences. The vestibular area to the distal root of the second mandibular molar presented the highest values in terms of angulation, height and thickness. There are no significant differences in the bone characteristics of MBS according to vertical growth patterns, sexes or hemiarchs. Angulation, height and thickness progressively increase from the vestibular bone of the mesial root of the first mandibular molar to the distal root of the second molar.

El propósito de esta investigación fue la evaluación tomográfica de la placa ósea mandibular (POM) en pacientes de ortodoncia con diferente patrón de crecimiento vertical. Se realizó un estudio de tipo observacional, descriptivo, transversal y retrospectivo. Se observó imágenes tomográficas de pacientes de 14 a 40 años de edad y se formó una base de datos con las que cumplían los criterios de selección. El tamaño de muestra fue de 10 para cada grupo según patrón de crecimiento vertical (hipodivergentes, normodivergentes e hiperdivergentes). Luego se seleccionaron cuatro zonas de inserción frecuente de minitornillos extralveolares en la POM, tomando como referencia las raíces mesial y distal del primer y segundo molar mandibular. Al realizar la comparación de las características de la POM entre patrones de crecimiento vertical, entre sexos y hemiarcadas no se encontraron diferencias estadísticamente significativas. Sin embargo, cuando se comparó las características de la POM según la raíz de referencia se encontró que había diferencias estadísticamente significativas. La zona vestibular a la raíz distal de la segunda molar mandibular presento los mayores valores en cuanto angulación, altura y grosor. No existen diferencias significativas en las características óseas de la POM según patrones de crecimiento vertical, sexos o hemiarcadas. La angulación, la altura y el grosor aumenta progresivamente desde el hueso vestibular de la raíz mesial del primer molar mandibular hacia la raíz distal del segundo molar.

Assuntos

RESUMO

OBJECTIVE: We report the orthodontic treatment of a class II malocclusion with anterior open bite and posterior crossbite in a patient with Down syndrome (DS) treated with mini-implants. METHODS: Treatment began with rapid maxillary expansion with a Haas appliance, followed by dental alignment and leveling with a fixed appliance and the correction of class II dental relationships with the use of orthodontic mini-implants associated with a sliding jig. RESULTS: The results obtained at the end of the treatment were satisfactory, with improvements in occlusion, including bite closure; maxillary expansion; and the correction of dental relationships. CONCLUSION: When well-planned, orthodontic treatment in a patient with DS achieves satisfactory results from a skeletal, occlusal, and facial perspective.

Assuntos

RESUMO

INTRODUCTION: The intrusion of posterior teeth had been considered challenging up to the development of orthodontic mini implants. In periodontally compromised teeth, the challenge is even greater, because of the root resorption risk due to periodontal ligament over-compression. Still, the precise strategy to determine the force reduction level remains uncertain. OBJECTIVE: The objective of the study was to determine, by a finite element analysis (FEA), the force reduction needed to avoid root resorption and maintain the efficiency of orthodontic mechanics of periodontally compromised teeth similar to the sound one. METHODS: An anatomical model was constructed representing a premolar inserted into a maxillary bone. Based on the initial model (R0), three bone height loss conditions were simulated (R2 = 2 mm, R4 = 4 mm, and R6 = 6 mm). Two intrusive movements were simulated: pure intrusion (bilateral mini implant) and uncontrolled-tipping intrusion (buccal mini implant). The hydrostatic stress at the periodontal ligament was used to evaluate the risk of root resorption due to over-compression. RESULTS: For bilateral mini implant intrusion, the force had to be decreased by 16%, 32% and 48% for R2, R4 and R6, respectively. For buccal mini implant intrusion, the required reductions were higher (20%, 36% and 56%). A linear relationship between the intrusive force reduction and the alveolar bone height loss was observed in both intrusion mechanics. CONCLUSIONS: According to the FE results, 8% or 9.3% of force reduction for each millimetre of bone height loss is suggested for intrusion with bilateral or buccal mini implant, respectively. The buccal mini implant anchorage must be associated with a supplemental strategy to avoid buccal crown tipping.

Assuntos

RESUMO

INTRODUCTION: The aim of the present study was to evaluate the thickness of the hard palate at the different angles formed by the palatal plane and the Frankfort horizontal line using computed tomography in patients with different facial patterns for planning the installation of MARPE. MATERIALS AND METHODS: The measurements were analysed in the hard palate of 106 patients. Four regions were selected passing through the mesial face, tangent at the level of the cemento-enamel junction of the premolars and molars. The bone thickness was measured from the floor of the nasal cavity to the cortical bone of the hard palate, 02 measurements with a distance of 05 mm between them (2.5 mm on each side starting from the midsagittal line) and 2 more with a distance of 7 mm between measurements (3.5 mm on each side starting from the midsagittal line). The palatal plane cant was determined based on the palatal plane and the Frankfort horizontal plane. The sagittal skeletal pattern was determined based on the ANB angle and the vertical skeletal pattern based on the SN.Go.Gn angle. RESULTS: Palatal bone thickness was greater in males than in females. Regarding the sagittal skeletal pattern, patients with Class II were found to have a thinner hard palate than Class I and Class III patients. No difference in the vertical skeletal pattern was observed between groups. Regarding the palatal plane cant, bone thickness was greater in patients with clockwise rotation. CONCLUSIONS: Careful planning should be considered in the case of female patients; patients with greater angles of the palatal plane cant and Class II patients have a smaller bone thickness.

Assuntos

RESUMO

Introduction: The purpose of this systematic review was to identify, evaluate, and provide information about palatal bone thickness in different vertical growth patterns for the placement of orthodontic anchorage devices. Methods: We performed a systematic review of the published data in Medline via PubMed, Web of Science, Cochrane Library, and Scopus from January 2000 to August 2022 using eligibility criteria. Data collection analysis and data extraction were performed independently by three reviewers. Sensitivity analyses were performed with the Cochrane risk of bias tool and the ROBINS-I tool was used for non-randomized studies. Results: A total of 343 articles were identified. The inclusion criteria included palatal bone thickness and vertical facial growth. However, both variables were found in 4 studies and only 2 had a control group. The different studies evaluated palatal bone thickness according to sex (male 14.1 mm; female 9.68 mm) and vertical malocclusion (normal 2.2 -12.6 mm; open bite 1.9 -13.2mm) with heterogeneous results. Likewise, the vertical growth pattern with a low angle (9.39 mm) was greater than the normal (8.55 mm) and high angle (7.53 mm). Conclusions: Palatal bone thickness varies according tp different vertical growth patterns, with the greatest thickness being found near the incisive foramen in hypodivergent individuals.

Introducción: El propósito de esta revisión sistemática fue identificar, evaluar y brindar información sobre el espesor óseo palatino en diferentes patrones de crecimiento vertical para la colocación de dispositivos de anclaje ortodónticos. Materiales y métodos: Realizamos una revisión sistemática de los datos publicados de Medline, a través de PubMed, Web of Science, Cochrane Library y Scopus. Se realizaron búsquedas sistemáticas con criterios de elegibilidad desde enero de 2000 hasta agosto de 2022. Tres revisores realizaron de forma independiente el análisis de recopilación de datos y la extracción de datos. Los análisis de sensibilidad se realizaron con la herramienta Cochrane de riesgo de sesgo y para estudios no aleatorios seleccionados de intervenciones se utilizó la herramienta ROBINS-I. Resultados: Se identificaron un total de 343 artículos. La elegibilidad de los estudios incluyó el grosor del hueso palatino y el crecimiento facial vertical. Sin embargo, ambas variables se encontraron en 4 estudios y solo 2 tenían grupo control. El espesor óseo palatino presentó resultados heterogéneos, los estudios evaluaron el espesor óseo palatino en cuanto al sexo (masculino: 14,1 mm; femenino: 9,68 mm), y maloclusión vertical (normal: 2,2-12,6 mm; mordida abierta: 1,9-13,2 mm). Asimismo, el patrón de crecimiento vertical con ángulo bajo (9,39 mm) fue mayor que el ángulo normal (8,55 mm) y ángulo alto (7,53 mm). Conclusiones: El grosor del hueso palatino muestra diferencia en los patrones de crecimiento vertical, el mayor grosor se encontró cerca del foramen incisivo en individuos hipodivergentes.

RESUMO

Resumo Objetivo: Demonstrar a confecção de um hyrax híbrido apoiado em mini-implante, para o tratamento da classe III. Caso clínico: Paciente D. B. S, sexo masculino, 07 anos de idade, com mordida anterior de topo e mordida cruzada posterior unilateral direita, apinhamento leve nos incisivos inferiores, perda precoce decorrente de cárie dos elementos dentários 54 e 64 e atresia maxilar, contribuindo para a diminuição do perímetro do arco. Discussão: Em pacientes que possuem deficiência maxilar o tratamento deve englobar a estimulação e o direcionamento maxilar através de forças ortopédicas. A terapia com a Expansão Rápida da Maxila (ERM) em associação com a Máscara Facial (MF) é o tratamento mais habitual para a má oclusão classe III sendo utilizada para o tratamento da maxila retruída e também para que se acelere o crescimento maxilar. A utilização da ancoragem esquelética como forma de tratamento precoce da classe III resulta em efeitos ortopédicos fundamentalmente maiores se comparado com o tratamento convencional, desta forma, permite que não haja deslocamento dentário provocado pela força exercida durante a protração maxilar e evitando perda de espaço no perímetro do arco. Conclusão: a ancoragem esquelética vem ampliando as fronteiras dos tratamentos ortodônticos e ortopédicos, aumentando, com isso, a época de início da terapia sem efeitos dentários adversos, sendo a modificação de um hyrax convencional para um híbrido uma opção de melhor custo benefício e biológico. (AU)

Abstract Objective: To demonstrate the construction of a mini-implant-supported hybrid hyrax for the treatment of class III. Case report: Patient DB S, male, 07 years old, with upper anterior bite and right unilateral posterior crossbite, light crowding of the lower incisors, early loss due to caries of the teeth 54 and 64 and maxillary atresia, contributing to the decrease in the perimeter of the arch. Discussion: In patients who have maxillary deficiency, treatment should include maxillary stimulation and direction through orthopedic forces. Therapy with Rapid Maxillary Expansion (RME) in association with Facial Mask (MF) is the most common treatment for class III malocclusion and is used for the treatment of retruded maxilla and also to accelerate maxillary growth. The use of skeletal anchorage as a form of early class III treatment results in fundamentally greater orthopedic effects compared to conventional treatment, thus allowing for no tooth displacement caused by the force exerted during maxillary protraction and avoiding loss of space in the perimeter of the bow. Conclusion: skeletal anchorage has been expanding the frontiers of orthodontic and orthopedic treatments, thereby increasing the time to start therapy without adverse dental effects, with the modification of a conventional hyrax to a hybrid being a more cost-effective and biological option. (AU)

Assuntos

RESUMO

Resumo Atualmente temos pacientes mais preocupados com a estética facial, e essa tem sido o principal motivo para a procura do tratamento ortodôntico, sendo a linha média facial um fator importante na análise morfológica do sorriso do ponto de vista estético. O desvio da linha média dentária atinge o complexo dentoalveolar, e ocorre quando existe um desequilíbrio entre os dentes e a base apical, do hemiarco direito e esquerdo ou entre os dentes superiores e os inferiores. A utilização de microparafusos como unidades de ancoragem, além de anular os efeitos colaterais indesejáveis, simplifica a mecânica ortodôntica, fornece uma maior previsibilidade ao resultado do tratamento, proporciona maior conforto e estética ao paciente, reduz o tempo de tratamento e possibilita a correção de casos com perdas dentárias, já que fornece uma ancoragem direta. O objetivo principal deste trabalho foi demonstrar através de um relato de caso clínico a correção da assimetria de desvio da linha média e uma melhor harmonia facial com a utilização de exodontias assimétricas de pré-molares e o uso de microparafusos ortodônticos de titânio como ancoragem (AU)

Abstract Currently, patients are more concerned with facial aesthetics, and this has been the main reason for seeking orthodontic treatment, with the facial midline being an important factor in the morphological analysis of the smile from an aesthetic point of view. Deviation from the dental midline affects the dentoalveolar complex, and occurs when there is an imbalance between the teeth and the apical base, of the right and left hemiarch or between the upper and lower teeth. The use of microscrews as anchorage units, in addition to canceling undesirable side effects, simplifies orthodontic mechanics, provides greater predictability of treatment results, provides greater comfort and aesthetics to the patient, reduces treatment time and allows for correction of cases with tooth loss, as it provides direct anchorage. The main objective of this work was to demonstrate, through a clinical case report, the correction of midline deviation asymmetry and better facial harmony with the use of asymmetric extraction of premolars and the use of titanium orthodontic microscrews as anchorage(AU)

Assuntos

RESUMO

Objective: to analyze the stress distribution in a 3D model that simulates second molar mesialization using two different types of mini-implants. Material and Methods: a mandible bone model was obtained by recomposing a computed tomography performed by a software program. The cortical and trabecular bone, a lower second molar, periodontal ligament, orthodontic tube, resin cement and the mini-implants were designed and modeled using the Rhinoceros 4.0 software program. The characteristics of self-drilling orthodontic mini-implants were: one with 7 mm length, 1 mm transmucosal neck section and 1.6 mm diameter and another with 5 mm length and 1.5 mm diameter. A total of 235.161 and 224.505 elements were used for the mesh. These models were inserted into the bone block and then subjected to loads of 200 cN (centinewton). The results were calculated and analyzed by the Ansys 17.0 software program for qualitative verification through displacement and maximum principal stress maps. Results: it was possible to observe that the periodontal ligament presented low displacement and stress values. However, the physiological values presented are among those capable to provide orthodontic movement, with compression and tensile area visualization staggered between 0.1 and -0.1 MPa (megapascal). Conclusion: within the limitations of the study, the mini-implants tested showed similar results where the load on the tooth allowed dental displacement (molar mesialization), with a tendency to rotate it, theoretically allowing the second molar to take the location of the first molar. (AU)

Objetivo: analisar a distribuição de tensões em um modelo 3D que simula a mesialização do segundo molar usando dois tipos diferentes de mini-implantes. Material e Métodos: um modelo de osso mandibular foi obtido por recomposição de uma tomografia computadorizada realizada por um software. O osso cortical e trabecular, um segundo molar inferior, ligamento periodontal, tubo ortodôntico, cimento resinoso e os mini-implantes foram projetados e modelados no software Rhinoceros 4.0. As características dos mini-implantes ortodônticos auto perfurantes foram: um com 7 mm de comprimento, 1 mm de secção transmucosa e 1,6 mm de diâmetro e outro com 5 mm de comprimento e 1,5 mm de diâmetro. Para a malha, foram utilizados 235.161 e 224.505 elementos. Esses modelos foram inseridos no bloco ósseo e então submetidos a cargas de 200 cN (centinewton). Os resultados foram calculados e analisados pelo software Ansys 17.0 para verificação qualitativa por meio de mapas de deslocamento e tensões máximas principais. Resultados: foi possível observar que o ligamento periodontal apresentou baixos valores de deslocamento e tensões. Porém, os valores fisiológicos apresentados são capazes de proporcionar movimentação ortodôntica, com visualização da área de compressão e tração escalonada entre 0,1 e -0,1 MPa (megapascal). Conclusão: dentro das limitações do estudo, os mini-implantes testados apresentaram resultados semelhantes onde a carga sobre o dente permitiu o deslocamento dentário (mesialização do molar), com tendência a girá-lo, permitindo teoricamente que o segundo molar ocupe do lugar do primeiro molar (AU)

Assuntos

RESUMO

ABSTRACT Objective: To evaluate the mechanical properties of mini-implants (MIs) manufactured from stainless steel and compare them with conventional titanium-aluminum-vanadium alloy MIs. Material and Methods: The following groups were formed: G1 (n=24), 8×1.5 mm steel MIs; G2 (n=24), 12×2.0 mm steel MIs; and G3 (n=24), 10×1.5 mm titanium MIs. The 72 MIs were inserted in the infra zygomatic crest region of the maxilla and retromolar trigone in the jaw of 10 pigs. Pull-out, insertion torque, fracture and percussion tests were performed in order to measure the tensile strength, primary stability and fracture strength of MIs. A digital torque gauge was used to measure insertion and fracture torque, a universal mechanical testing machine was used for pull-out testing and a periotest device was used to measure the micromovement of MIs. For morphological and MI component evaluation, scanning electron microscopy (SEM) was performed. D'Agostino & Pearson, Kruskal-Wallis, and Dunn post-hoc and normality tests were used. Results: G2 insertion and fracture torques were significantly higher than G1 and G3 insertion and fracture torques (p<0.05). The pull-out and percussion tests presented similar values among the groups. SEM revealed that the fracture point was predominantly on the fourth thread for steel MIs (G1 and G2) and on the seventh thread for titanium-aluminum-vanadium MIs (G3). Conclusion: The mechanical properties of stainless steel MIs are superior to those of titanium-aluminum-vanadium alloy MIs.

Assuntos

RESUMO

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

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