Intrusión acelerada con miniimplantes y corticotomía para crear espacio protésico para implante

La ausencia de un diente puede originar sobre-erupción de su antagonista debido al movimiento fisiológico. Distintos métodos se han empleado para lograr la rehabilitación en espacios interoclusales reducidos, la mayoría implica un tallado del diente antagonista o incluso la extracción dental. La intrusión dental periodontalmente asistida (corticotomía), es una alternativa terapéutica en la que el tallado del diente extruido ya no es necesario, conservando su integridad coronaria. Reporte de caso: Paciente femenino de 56 años con ausencia del 4.7, además presenta sobre-erupción del 1.7, limitando el espacio interoclusal y su rehabilitación. Se realizó intrusión del 1.7 mediante corticotomía con el Piezoeléctrico (técnica Piezocision) así como la colocación de minitornillos de ortodoncia para anclaje. Obtenido dicho espacio interoclusal, se rehabilitó con un implante dental. Conclusiones: La intrusión de molares con el apoyo de mini-implantes y corticotomías es un procedimiento que tiene como beneficio la creación de un espacio interoclusal para su restauración en un periodo corto de tiempo, sin tallar la estructura dentaria.

The absence of a tooth can cause over-eruption of its antagonist due to a physiological movement. Different methods have been used to achieve rehabilitation in reduced interocclusal spaces. Most of them involve the wear of the opposing tooth or even dental extraction. Periodontal-assisted dental intrusion is a therapeutic alternative that does not require the reduction of the extruded tooth and preserves its structure. Case report: 56-year-old female patient with absence of tooth 4.7, also presenting an over-eruption of 1.7, limiting the interocclusal space and rehabilitation. Intrusion of tooth 1.7 was performed with corticotomy using the piezocision technique and placement of mini-screws followed by the placement of a dental implant. Conclusions: The intrusion of molars aided by orthodontic mini-screws and piezocision technique is an effective treatment, whose benefit is the creation of an ideal prosthetic space in a short period of time, avoiding the reduction of dental structure.

The Influence of Different Traction Hooks on Tooth Movement During Distalization of the Lower Dentition: A Finite Element Analysis / 医用生物力学

Objective To study stress distributions of lower dentition distally moved with miniscrews in external oblique line area when the traction hooks with different lengths were placed at different positions by the three-dimensional (3D) finite element method. Methods Based on cone beam computed tomography (CBCT) data from a patient, traction hooks with the heights of 2 mm and 7 mm were constructed and fixed between the lateral incisors and the canine brackets, as well as between the canines and the first premolar brackets. Four kinds of 3D finite element models of full dentition distally moved with miniscrews were constructed. The 3 N traction force was loaded between the traction hook and the miniscrews. The maximum von Mises stress and initial displacement of the mandibular teeth and dentition under four working conditions were analyzed. ResultsWhen the traction hook with 7 mm-height was placed between the lateral incisor and the canine, the lower central incisor rotated clockwisely, with the crown moving labially and the root moving lingually. But under the other three working conditions, the central incisor rotated counterclockwisely, and the crown and root moved lingually. When the traction hook with 7 mm-height was placed between the canine and the first premolar, the lower canine crown moved proximally. But under the other three working conditions, both the crown and root moved distally. Under four working conditions, the mandibular molars all rotated counterclockwisely,with the crown and root moving distally. Conclusions Through 3D finite element analysis, biomechanical mechanism of the effect of different traction hooks on mandibular tooth movement during distalization of the lower dentition was elucidated.With full understanding of the biomechanical mechanism, proper selection for length and placement of the traction hook can achieve distal movement of the entire mandibular dentition more efficiently.

Microtornillos como método de control vertical en desprogramación muscular / Vertical control with miniscrews in muscular deprogramming treatment

Una de las consecuencias de la desprogramación neuromuscular es la rotación mandibular en sentido horario, evidenciando el punto prematuro de contacto y aumentando la dimensión vertical del paciente. En pacientes clase II con componente vertical, es un problema realizar este tipo de tratamiento, ya que por lo general este efecto de posterorrotación mandibular hace el perfil más convexo, y en algunos casos genera mordida abierta anterior, la cual se debe corregir posteriormente con el tratamiento de ortodoncia, cirugía o prótesis, lo que alarga el tiempo total de tratamiento por la necesidad de control vertical. El presente caso se trata de una mujer de 45 años de edad, dolicofacial, con tendencia a mordida abierta, mordida dual, sobremordida vertical y horizontal disminuidas, motivo de consulta dolor articular, el cual no le permite continuar con sus labores diarias, el tratamiento realizado fue desprogramación neuromuscular con un guarda oclusal inferior con el propósito de aliviar sintomatología articular y control vertical con microtornillos palatinos previo a tratamiento ortodóncico (AU)

One of the effects of the neuromuscular deprogramming treatment is the mandibular clockwise rotation, making the light premature occlusal contact more evident and increasing the patient vertical dimension. In Class II patients with vertical component is difficult to treat them due to profile worsening as an effect of the clockwise rotation creating in some patient's anterior open bite, this has to be corrected later in treatment with orthodontic intrusion, surgery or prosthodontic treatment, increasing the total time of treatment with the vertical control necessity. This case report is a 45 years old patient, dolichofacial, with anterior open bite tendency, dual bite, decreased overjet and overbite, her chief complaint was temporomandibular joint dysfunction which dont allow her to do her daily duties, the treatment for her was neuromuscular deprogramming splint for the temporomandibular joint pain, and vertical control with temporary anchorage devices (miniscrews) before the orthodontic treatment (AU)

Failure rates of miniscrews inserted in the maxillary tuberosity

ABSTRACT Introduction: Anchorage conservation in orthodontics has always been a challenge. Objective: The aim of this current study was to find out the failure rate of miniscrews inserted in the maxillary tuberosity (MT) region. Methods: This pilot study consisted of 40 patients (23 female, 17 male; mean age = 20.1±8.9 years) that had received 60 MT miniscrews for orthodontic treatment. Clinical notes and pictures were used to find out the primary outcome of miniscrew failure. Independent failure factors were also investigated. Logistic regression analysis was done for predictor's relation with MT miniscrews failure. Results: There was no significant correlation in failure rate according to various predictor variables, except for miniscrews installed by lesser experienced operators, which showed significantly more failure. The odds ratio for miniscrew failure placed by inexperienced operators was 4.16. Conclusion: A 26.3% failure rate of mini-implants inserted in the MT region was observed.

RESUMO Introdução: a manutenção da ancoragem sempre foi um desafio na Ortodontia. Objetivo: o objetivo do presente estudo foi descobrir a taxa de falhas dos mini-implantes instalados na região da tuberosidade maxilar (TM). Métodos: o presente estudo piloto avaliou 40 pacientes (23 mulheres, 17 homens; idade média = 20,1 ± 8,9 anos) que receberam 60 mini-implantes na TM durante o tratamento ortodôntico. Anotações clínicas e fotografias foram usadas para investigar o principal motivo para a falha do mini-implante. Fatores de insucesso independentes também foram investigados. Uma análise de regressão logística foi realizada para medir o impacto de cada fator preditivo sobre a falha na instalação dos mini-implantes na TM. Resultados: as diferentes variáveis preditivas não demonstraram correlação significativa com a taxa de falhas, com exceção da instalação dos mini-implantes realizada por operadores inexperientes, que mostrou quantidade significativamente maior de falhas. A razão de chances para a falha dos mini-implantes instalados por operadores inexperientes foi de 4,16. Conclusão: observou-se uma taxa de falhas de 26,3% para os mini-implantes instalados na região da TM.

Biomechanics of extra-alveolar mini-implants

ABSTRACT It is undeniable that extra-alveolar mini-implants anchorage has revolutionized Orthodontics. Correspondingly, the proper understanding of mini-implants biomechanics allowed to broaden the range of dental movements as never seen before in clinical practice. However, in order to produce better treatments, especially regarding the effects in occlusal plane, it is important to be aware of the numerous possibilities of applying force systems based on skeletal anchorage. Thus, this paper aims to address, by means of clinical cases, the application of biomechanics concepts that are extremely relevant to the proper employment of extra-alveolar mini-implants.

RESUMO É inegável que a ancoragem com mini-implantes extra-alveolares revolucionou a nossa especialidade. No mesmo sentido, o correto entendimento da biomecânica com mini-implantes permitiu ampliar a gama de movimentos dentários como nunca visto na prática clínica. Deve-se, porém, atentar às diversas possibilidades dos sistemas de aplicação das forças decorrentes do uso da ancoragem esquelética, com vistas a produzir tratamentos cada vez mais eficientes, principalmente em relação aos efeitos no plano oclusal. Assim, o presente artigo versa, por meio de casos clínicos, sobre a aplicação de conceitos da biomecânica que são extremamente relevantes para o correto emprego dos mini-implantes extra-alveolares.

Resolución de clase II mordida profunda con distalamiento molar mini-iimplantoasistida: reporte de caso clínico / Resolution of a class II deep bite with mini-implant-assisted molar distal movement; report of a clinical case

En todos los tratamientos ortodónticos, el primer objetivo a cumplir es alinear y nivelar las piezas dentales. Para tal fin, deberíamos generar espacio dentro del arco dentario. Existen tres procedimientos diferentes para lograr este objetivo, según el grado de apiñamiento dental o Índice de nance, que son los siguientes: a) stripping o desgaste interproximal, b) exodoncia de piezas dentales y c) distalamiento. La distalización de los molares es una de las técnicas más antiguas de la terapéutica ortodóntica y se han empleado distintos recursos terapéuticos para tal fin, como pendulum, jig de jans, first class, entre otros; cada uno con sus ventajas y desventajas. La introducción de los mini-implantes dentro de nuestra especialidad ha revolucionado en forma drástica los conceptos de anclaje, brindándonos movimientos dentarios sin generar efectos colaterales indeseables. El objetivo de este caso clínico, es mostrar la utilización de un Orthorama modificado y mini-implantes como distaladores de los molares superiores (AU)

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.

Comparison of the aesthetics stability of titanium miniscrews onto the distal molar displacement between two different implanted sites / 中华医学美学美容杂志

Objective To compare the stability and clinical efficacy of the distal molar displacement with titanium miniscrews.Methods A total of 82 Class Ⅱ patients with non-extraction (excluding orthognathic surgery) were selected.31 males and 50 females were treated with titanium miniscrews.15 males and 25 females were implanted with a miniscrews between the second premolar and the first molar on both sides of the maxillary palate.16 males and 25 females were bucally implanted between first and second molars.The failure rates and effect of molar displacement of miniscrews between two different implanted sites were compared.Results Group of implants palatally had a 17.6％ failure rate.And group of implants buccally had a 23.0％ failure rate.The failure rate of the former was lower than that of the latter.The difference was statistically significant (P＜0.05),and the former had more molar than the latter (P＜0.05)；the lateral profile was significantly improved and the clinical curative effect was better.Conclusions The stability and clinical efficacy of the distal molar displacement with titanium miniscrews in the palatal side are better.

Effect of Laser Pre-Drilling on Insertion Torque of Orthodontic Miniscrews: A Preliminary Study

PURPOSE: To evaluate the effect of different-sized drill tips and laser irradiation times on the initial stability of orthodontic miniscrews placed in Er,Cr:YSGG-laser pre-drilled holes in an animal model. MATERIALS AND METHODS: Laser pre-drilled holes were made in dog mandibular bone with an Er,Cr:YSGG laser using irradiation times of 5, 7, 9, 11, and 13 seconds, and tip diameters of 0.4 and 0.6 mm. The maximum diameter and depth of the pre-drilled holes was measured with micro computed tomography. The maximum insertion torque was measured during placement the miniscrew. RESULT: Laser pre-drilled holes were conical shaped. The maximum diameter of pre-drilled holes increased with longer laser irradiation times (P>0.05) and larger tip diameters (P < 0.05). The depth of pre-drilled holes increased with longer laser irradiation times and larger tip diameters (P < 0.05). When the 0.4 mm tip, but not the 0.6 mm tip, was used, the insertion torque decreased significantly with longer laser irradiation times (P < 0.05). CONCLUSION: Tip diameter impacted insertion torque more than irradiation time. It takes at least 9 seconds using a 0.6 mm tip to create a 0.8 mm diameter and 1.0 mm depth hole in thick cortical bone.

Stress distributions in peri-miniscrew areas from cylindrical and tapered miniscrews inserted at different angles / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to analyze stress distributions in the roots, periodontal ligaments (PDLs), and bones around cylindrical and tapered miniscrews inserted at different angles using a finite element analysis. METHODS: We created a three-dimensional (3D) maxilla model of a dentition with extracted first premolars and used 2 types of miniscrews (tapered and cylindrical) with 1.45-mm diameters and 8-mm lengths. The miniscrews were inserted at 30°, 60°, and 90° angles with respect to the bone surface. A simulated horizontal orthodontic force of 2 N was applied to the miniscrew heads. Then, the stress distributions, magnitudes during miniscrew placement, and force applications were analyzed with a 3D finite element analysis. RESULTS: Stresses were primarily absorbed by cortical bone. Moreover, very little stress was transmitted to the roots, PDLs, and cancellous bone. During cylindrical miniscrew insertion, the maximum von Mises stress increased as insertion angle decreased. Tapered miniscrews exhibited greater maximum von Mises stress than cylindrical miniscrews. During force application, maximum von Mises stresses increased in both groups as insertion angles decreased. CONCLUSIONS: For both cylindrical and tapered miniscrew designs, placement as perpendicular to the bone surface as possible is recommended to reduce stress in the surrounding bone.

Assessment of stability of orthodontic mini‑implants under orthodontic loading: A computed tomography study.

Objectives: Miniscrews have been used in recent years for anchorage in orthodontic treatment. However, it is not clear whether the miniscrews are absolutely stationary or move when force is applied. This prospective clinical study was undertaken to evaluate the mobility of orthodontic miniscrews under orthodontic loading using computed tomography. Materials and Methods: Ten adult patients (7 females and 3 males with mean age of 19 years, 7 mm overjet) who required en masse retraction of upper and lower anterior teeth in first premolar extraction spaces were included in this study. After initial alignment of anterior teeth, the 0.019” ×0.025” stainless steel archwire were placed in preadjusted edgewise appliance. The miniscrews (diameter - 1.3 mm, length - 7 mm) were inserted in between second premolar and the first molar in the maxilla (zygomatic buttress) and in mandible on the buccal side as direct anchorage. Immediately after placement of miniscrews without waiting period, NiTi coil springs (force of 150 g in the maxilla and 100 g in the mandible) were placed for the retraction. Denta Scans were taken immediately before force application (T1) and 6 months later (T2). The mean changes obtained at T1 and T2 in Denta Scans (axial plane, coronal plane, paraxial plane) were evaluated to determine any movement of different parts of miniscrews using one-way ANOVA test and Student’s unpaired t-test. Results: On average, miniscrews were extruded and tipped forward significantly, by 1 mm at the screw head in the axial plane (Group III) and 0.728 mm in the coronal plane (Group IV). Tail of miniscrews showed average tipping of 0.567 mm in the axial plane (Group I) and 0.486 mm in the paraxial plane (Group V). Least average mobility was shown by screw body of 0.349 mm in the axial plane (Group II). Clinically, no significant mobility was observed. Conclusion: Miniscrews are a stable anchorage for orthodontic tooth movement but do not remain absolutely stationary like an endosseous implant throughout orthodontic loading although miniscrews might move according to placement site, orthodontic loading, and inflammation of peri-implant tissue. Waiting period between miniscrews placement and orthodontic loading does not significantly affect the miniscrew mobility so immediate loading can be recommended. To prevent hitting any vital organs because of miniscrew mobility, it is recommended that they can be placed in a nontooth-bearing area that has no foramen, major nerves, or blood vessel pathway, or in a tooth-bearing area allowing a 1.5 mm safety clearance between the miniscrew and dental root.

A digital volumetric tomography (DVT) study in the mandibular molar region for miniscrew placement during mixed dentition

OBJECTIVE: To assess bone thickness for miniscrew placement in the mandible during mixed dentition by using digital volumetric tomograph (DVT). MATERIAL AND METHODS: A total of 15 healthy patients aged 8-10 years old, with early exfoliated mandibular second deciduous molar, were included. DVT images of one quadrant of the mandible were obtained using Kodak extraoral imaging systems and analyzed by Kodak dental imaging software. The error of the method (EM) was calculated using Dahlberg's formula. Mean and standard deviation were calculated at 6 and 8 mm from the cementoenamel junction (CEJ).Paired t-test was used to analyze the measurements. RESULTS: Buccal cortical bone thickness, mesiodistal width and buccolingual bone depth at 6 mm were found to be 1.73 + 0.41, 2.15 + 0.49 and 13.18 + 1.22 mm, respectively; while at 8 mm measurements were 2.42 + 0.34, 2.48 + 0.33 and 13.65 + 1.25 mm, respectively. EM for buccal cortical bone thickness, mesiodistal width and buccolingual bone depth was 0.58, 0.40 and 0.48, respectively. The difference in measurement at 6 and 8 mm for buccal cortical plate thickness (P < 0.05) and buccolingual bone thickness (P < 0.05) was found to be significant, whereas for mesiodistal width it was insignificant (P > 0.05). CONCLUSION: Bone thickness measurement has shown promising evidence for safe placement of miniscrews in the mandible during mixed dentition. The use of miniscrew is the best alternative, even in younger patients. .

OBJETIVO: avaliar, por meio de tomografia volumétrica digital (TVD), a espessura óssea necessária para a instalação de mini-implante na arcada inferior durante a fase de dentição mista. MÉTODOS: um total de 15 pacientes saudáveis, com idades entre 8 e 10 anos, com segundo molar inferior decíduo irrompido recentemente, foram incluídos no presente estudo. Imagens de TVD da hemiarcada inferior foram obtidas utilizando sistemas de imagens extrabucais Kodak. As imagens foram analisadas por meio do programa de imagens Kodak. O erro do método (EM) foi calculado utilizando a fórmula de Dahlberg. Médias e desvios-padrão foram calculados de 6 a 8mm aquém da junção amelocementária. O teste t foi utilizado para a análise das medidas. RESULTADOS: a espessura do osso cortical vestibular, largura mesiodistal e profundidade óssea vestibulolingual, a 6mm, foram de 1,73 + 0,41; 2,15 + 0,49; e 13,18 + 1,22 mm, respectivamente. Já a 8mm, os valores foram de 2,42 + 0,34; 2,48 + 0,33; e 13,65 + 1,25mm. O EM para a espessura do osso cortical vestibular, largura mesiodistal e profundidade óssea vestibulolingual foi de 0,58, 0,40 e 0,48mm, respectivamente. A diferença entre as medidas a 6 e 8mm para a espessura do osso cortical vestibular (p < 0,05) e a espessura óssea vestibulolingual (p < 0,05) foi significativa, embora não tenha sido significativa para a largura mesiodistal (p < 0,05). CONCLUSÃO: a mensuração da espessura óssea demonstra evidências promissoras para a segura instalação de mini-implantes na arcada inferior e na fase de dentição mista. O uso de mini-implantes tem se mostrado a melhor alternativa, mesmo nos casos de pacientes mais jovens. .

Intrusion of Overerupted Molars using Miniscrews and TMA Spring: A Case Report.

Over eruption of posterior tooth due to the loss of antagonist teeth causes occlusal and functional disturbances. To restore proper occlusion, intrusion of the overerupted tooth becomes essential before multidisciplinary reconstructive dental approaches can be initiated. Conventional orthodontic techniques do not intrude posterior teeth eff ectively, and almost all methods result in anterior extrusion rather than posterior intrusion. New absolute anchorages (miniscrews and miniplates) are said to make posterior tooth intrusion possible. Th is case report describes the treatment of a patient with supra-erupted maxillary right and left fi rst molars intruded with titanium molybdenum alloy spring and miniscrew anchorage. Th e results showed that the biological responses of the teeth and the surrounding bony structures to the intrusion appeared normal and acceptable. Periodontal health and vitality of the teeth were maintained throughout the treatment.

Thickness distribution of adolescent palatal bone studied by CBCT / 实用口腔医学杂志

Objective:To study the thickness distribution palatal bone in adolescents and provide a clinical reference for implanting mini-screws.Methods:Cone-beam CT head scan data of palate of 20 adolescent orthodontic patients were measured with NNT Viewer software.60 points of the palate bone on one side were designed as 1 -10 in sagittal direction and as A -F in transvers direction with incisive foramen as the point of A and 0,the distance between each 2 adjacent points was 2 mm.The bone thickness of the 60 points were measured and statistically analyzed.Results:There were no significant differences among B2,B3,C2,C3,D3,E3,E4,F4 and F5(P >0.05).Statistically significant difference was found between F3 and B2 or B3,C2,C3,D3,E3,E4,F4 and F5(P ＜0.05).There was significant difference between D3 and D4(P ＜0.05).Conclusion:The appropriate areas for implanting mini-screws in palate may be about 2 -4 mm near the palatal suture and 4 -6 mm behind incisor canal,and 8 -10 mm near the palatal su-ture,6 -8 mm behind incisor canal.Those regions are safe for implanting mini-screws and can provide about 6 mm bone tissue sup-port.

Utilização de miniparafusos com sistema de aparelhos autoligados na correção da Classe II em pacientes portadores de problemas periodontais / Utilization of miniscrews with self-ligating appliances on the correction of Class II in patients with periodontal conditions

O número de tratamentos ortodônticos em pacientes adultos, que frequentemente apresentam problemas periodontais, ausências dentárias e próteses, aumentou muito nos últimos tempos. Com este novo panorama, novas estratégias devem ser utilizadas para atender às necessidades específicas destes tipos de pacientes, como estética, forças suaves, menor tempo de tratamento e menor dependência da colaboração. O uso de ancoragem esquelética associada aos aparelhos autoligados reduz o número de extrações de pré-molares, emprega uma mecânica simples e eficiente, minimiza os efeitos colaterais indesejados, diminui a necessidade de colaboração do paciente e torna os tratamentos mais previsíveis. Este artigo ilustra a correção de uma má oclusão de Classe II de Angle, de natureza dentoalveolar, cujo caso também apresentava mordida cruzada e problemas periodontais. Foram utilizados miniparafusos ortodônticos para efetuar a distalização do arco superior e corrigir a Classe II, associados ao sistema de aparelhos autoligados com fios termoativados. Esta associação trouxe benefícios na correção ortodôntica da paciente com problemas periodontais, pois houve ganho de inserção clínica por meio da formação de epitélio juncional longo, especialmente na região anterossuperior, após movimentação ortodôntica leve, realizada com o sistema de aparelhos autoligados. Tal associação reduziu a intensidade das forças aplicadas, evitou o uso de elásticos de Classe II e diminui a quantidade de consultas sem prejudicar a eficiência da correção.

The number of orthodontic treatment for adult patient has increased considerably. These patients frequently present periodontal conditions, absent teeth and prosthesis. In this scenario, new strategies must be used to meet specific needs of these patients such as: gentle force, aesthetics and briefer treatments requiring lower compliance. Skeletal anchorage associated with sel-ligating appliances reduces the number of pre-molars extraction. It uses simple and efficient mechanics, minimizes undesirable side-effects and reduces the need of compliance of patients, resulting on a more predictable treatment. The present article illustrates the correction of Angle Class II malocclusion of dentoalveolar nature, associated to crossbite and periodontal conditions. Orthodontic mini-screws were used to perform distalization of the maxillary arch for the correction of Class II, combined with self-ligating appliance with heat-activated wire. This association brought benefits to the corrective orthodontic treatment of a patient with periodontal conditions since there was a gain on clinical attachment due to the formation of long junctional epithelium, especially on the anterosuperior region after light orthodontic movement performed with self-ligating appliance. The association also reduced the forces applied; avoid the use of Class II elastics and reduced the number of appointments without compromising the efficiency of the correction.

Análisis estructural de mini-implantes ortodónciso / Mini-structural analysis of orthodontic implants

Los mini-implantes son en la actualidad una herramienta ideal para obtener un anclaje máximo y solucionar un sinfín de problemas clínicos ortodóncicos. Son dispositivos fabricados con titanio grado V (Ti-6AI-4V), que los vuelve más resistentes a la fractura y menos propensos a la oseointegración. El siguiente trabajo tuvo como objetivo reunir diversos estudios de la literatura actual sobre los mini-implantes, para facilitar el entendimiento del asunto al ortodoncista clínico y odontólogos interesados en conocer este dispositivo. Este trabajo reunió estudios en relación a los aspectos clínicos y estructurales de los mini-implantes. Se hizo hincapié en los aspectos estructurales de los mini-implantes, ya que la literatura es escasa en este sentido. Se concluyó que los mini-implantes son dispositivos de anclaje temporario muy útiles en el tratamiento ortodóncico. Siguiendo las orientaciones establecidas y confeccionados de materiales estandarizados internacionalmente, los mini-implantes pueden ser usados en forma segura en seres humanos

Nowadays, the mini-implants are an ideal tool to obtain maximum anchorage solving an endless number of clinical orthodontic problems. These devices are made by titanium grade V (Ti-6Al-4V), which makes them more resistant to breakage and less inclined to osseointegration. By bringing together many studies on the mini-implants' current literature, this article aimed the understanding of the clinical orthodontists and dentists interested in work with this device. The topics are related with the biological, surgical and structural mini-implants. This article emphasized the structural aspects of the mini-implants because the literature is scarce in this important topic. The conclusion was that mini-implants are a temporary anchorage devices very useful in the orthodontic treatment. If followed the guidelines established and using manufactured materials internationally standardized, mini-implants can be used safely in humans

Disjunção maxilar com Haas modificado associado a microimplantes / Maxillary disjunctor with haas modified associated to miniscrews

Em casos de tratamento da atresia maxilar, inúmeros disjuntores palatinos podem ser usados. Nesse caso foi escolhido o disjuntor maxilar do tipo Haas, que é dento mucossuportado. Variáveis como idade do paciente e grau de maturação óssea devem ser considerados. A primeira tentativa de disjunção com disjuntor Haas não obteve sucesso, levando os profissionais ao estudo e elaboração de um novo aparato. Por ser muco-ósseos suportado,fixado com microimplantes, tal aparato obteve sucesso por dirigir todas as suas forças para a sutura palatina, sem a dissipação nos dentes.

In cases of treatment of palatal maxillary expansion many apparatus can beused. This case was chosen rapid maxillary expansion (RME) with Haas, who is gum-dental supported. Variables such as patient age, degree of maturation must be considered. The first attempt to switch Haas disjunction with no success, leading professionals to study and prepare a new apparatus. Be supported by mucus bone fixed with miniscrews, this apparatus has been successful by directing ali its forces to the suture without dissipation in the teeth.

The optimal position for insertion of orthodontic miniscrews / O posicionamento ótimo para inserção de miniimplantes ortodônticos

PURPOSE: Miniscrews feature several advantages over other devices used to achieve anchorage; however, using computed tomography (CT) scans to determine the appropriate areas to place these devices for all patients can be expensive. This study aimed to determine the optimal interradicular spaces for miniscrew placement in the mandible and maxilla. METHODS: Using CT images from 12 adult patients, mean interradicular distance and standard deviation values were obtained at heights of 2, 5, 8 and 11 mm from the alveolar bone crest. The means were compared with mean data from the literature. RESULTS: Considering a height of 3 mm, the most favorable mandibular interradicular distances were found between the first and second molars, first and second premolars, and finally between the canines and first premolars. The most favorable maxillary interradicular spaces were found between the canines and first premolars, between premolars, and between the second premolar and first molar. CONCLUSION: The safest interradicular site for miniscrew insertion in the mandible was found to be between the first and second molars, whereas in the maxilla, this site was between the canines and first premolars.

OBJETIVO: Miniimplantes apresentam vantagens sobre outros dispositivos utilizados como recurso de ancoragem, mas a determinação de áreas adequadas, por meio de tomografia computadorizada (TC) em todos os casos pode ser dispendiosa. Este estudo teve como objetivo avaliar o espaço interradicular adequadas para a inserção dos miniimplantes na maxila e mandíbula. METODOLOGIA: Usando TC de 12 pacientes adultos, foram obtidas média e desvio padrão para a distância interradicular nas alturas de 2, 5, 8 e 11 mm a partir da crista do osso alveolar. As médias foram comparadas com dados da literatura e médias foram novamente obtidas. RESULTADOS: Levando em conta a altura de 3 mm, a distância interradicular mais favorável na mandíbula foi encontrada entre os primeiros e segundos molares, entre primeiro e segundo pré-molares e, finalmente, entre caninos e primeiros pré-molares, respectivamente. Na maxila, os espaços interradiculares mais favoráveis foram encontrados entre caninos e primeiros pré-molares, entre pré-molares e entre segundos pré-molares e primeiro molar, respectivamente. CONCLUSÃO: O local mais seguro para a inserção de miniimplantes interradiculares na mandíbula foi encontrada entre os primeiros e segundos molares, enquanto que na maxila, entre os caninos e primeiros pré-molares.

Titanium alloy miniscrews for orthodontic anchorage: an in vivo study of metal ion release / Minimplantes de liga de titânio para ancoragem ortodôntica: um estudo in vivo de liberação de íon metálico

PURPOSE: To examine and compare the levels of several metal ions released in the saliva of patients with orthodontic appliances, at different time points before and after insertion of a miniscrew. METHODS: Saliva of patients (n=20) was collected at four time points: before miniscrew placement (T1), 10 minutes (T2), 7 days (T3) and 30 days after miniscrew placement (T4). The salivary samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES). The release of nine different metal ions was observed: titanium (Ti), zinc (Zn), chromium (Cr), nickel (Ni), iron (Fe), copper (Cu), aluminum (Al), Vanadium (V) and cobalt (Co). Data were analyzed by descriptive statistics. Salivary metal concentrations from different time points of miniscrew treatment were compared using Wilcoxon paired tests (a=5 percent). RESULTS: At time point T4, there was a quantitative increase in the salivary concentration of Cu, Ti, V, Zn, as well as a quantitative decrease in the salivary concentration of Al, Co, Cr, Fe, Ni, when compared with T1. CONCLUSION: It can be concluded that the placement of fixed orthodontic appliances associated with miniscrews does not lead to an increase of salivary metal ion concentrations.

OBJETIVO: Examinar e comparar os níveis de diferentes íons metálicos liberados na saliva de pacientes com aparelhos ortodônticos, em diferentes tempos: antes e após a inserção de mini-implantes. METODOLOGIA: A saliva de pacientes (n=20) foi coletada em quatro tempos diferentes: antes da inserção do mini-implante (T1), 10 minutos (T2), 7 dias (T3) e 30 dias após a remoção do mini-implante (T4). As amostras de saliva foram analisadas por espectrometria de massa de plasma com acoplamento por indução (ICP-MS) e espectrometria de emissão ótica por plasma acoplado indutivamente (ICP-OES). A liberação de nove diferentes ions metálicos foi observado: titânio (Ti), zinco (Zn), cromo (Cr), níquel (Ni), ferro (Fe), cobre (Cu), alumínio (Al), vanádio(V) e cobalto (Co). Os dados foram analisados por estatística descritiva. As concentrações de íons metálicos na saliva dos diferentes tempos estudados foram comparados através do teste pareado de Wilcoxon (a=5 por cento). RESULTADOS: No tempo T4, houve um aumento quantitativo na concentração salivar de Cu, Ti, V, Zn, assim como um decréscimo quantitativo na concentração salivar de Al, Co, Cr, Fe, Ni, quando comparados com T1. CONCLUSÃO: Pode ser concluído que a colocação de aparelho fixo ortodôntico associado com mini-implantes não leva a um aumento significativo na concentração salivar de íons metálicos.

Mini-implantes ortodônticos: protocolo para higienização e manutenção da saúde peri-implantar / Orthodontic mini-implants: protocol for cleaning and maintenance health peri-implant

O objetivo do presente artigo foi elaborar um protocolo para higienização de mini-implantes ortodônticos, possibilitando com isso, a manutenção da saúde na região peri-implantar e por conseguinte, estabilidade secundária desses dispositivos.

The purpose of this article was preparing a protocol for cleaning of orthodontic mini-implants, enabling with this, health maintenance peri-implant in the region and therefore stability of these secondary devices.