Estudo clínico da retração de caninos e perda de ancoragem com a mola T do grupo A e estudos analíticos da mola T do grupo A e B

Objetivo: Avaliar a retração parcial de caninos utilizando a mola “T” (TTLS) do grupo A a e a perda de ancoragem dos molares, analisar mecanicamente a mesma TTLS e também avaliar a pré-ativação da TTLS do grupo B, por curvatura e dobras. Material e Método: Quatro artigos científicos foram redigidos e utilizados para a avaliação dos propósitos apresentados. Resultados: Os caninos superiores foram retraídos 3,2 mm, enquanto os inferiores foram retraídos 4,1 mm. Os molares superiores e inferiores foram protraídos 1,0 mm e 1,2 mm, respectivamente. Os caninos se movimentam 1,5 mm no primeiro mês e 2,43 mm no segundo. A TTLS do grupo A deve ter 7 X 10 mm, e ao ser ativada 4 mm, ficar posicionada a 2 mm do bráquete anterior e ter a dobra de gable a 4 mm do tubo posterior. A pré-ativação da TTLS do grupo B por curvatura gerou M/F em média 2,5 mm maiores que a pré-ativação por dobras. Conclusões: Os caninos superiores foram retraídos por inclinação controlada, enquanto os inferiores foram retraídos por inclinação descontrolada. Os molares superiores e inferiores foram protraídos por inclinação controlada. Em 2,1 meses de retração de 14 caninos, a perda de ancoragem dos molares foi de 0,3 :1. Os caninos se movimentam mais no segundo mês do que no primeiro. Foi possível desenvolver uma padronização e otimização da TTLS pré-ativada para o grupo A. A pré-ativação da TTLS do grupo B por curvatura gerou M/F maiores quando comparada a pré-ativação por dobras.Objective: To evaluate both the partial retraction of canines and the loss of anchorage of the molars using a Group A Titanium “T” Loop Spring (TTLS), and also to evaluate the preactivation differences of curvature vs. bends on a group B TTSL. Materials and Method: Four research papers were written and analyzed for the evaluation of the aims presented. Results: Upper canines were retracted 3.2 mm, while the lower ones were retracted 4.1 mm. The upper and lower molars were protracted 1.0 and 1.2 mm, respectively. The canines were moved 1.5 mm in the first month and 2.43 mm on the second, on average. The group A TTLS should have 7 X 10 mm, and on 4 mm of activation, it should be located 2 mm from the anterior bracket with its preactivation bend positioned 4 mm from the posterior tube. The group B TTLS preactivated by curvature generated M/F ratios 2.5mm larger than the bend preactivation, on average. Conclusions: The upper canines were retracted by controlled tipping, while the lower ones were retracted by uncontrolled tipping. The upper and lower molars were protracted by controlled tipping. In 2.1 months of canine retraction, the loss of anchorage was 0.3:1, compared to the canines. The canines were moved more in the first month than on the 16 second. It was possible to develop a standard and an optimization for the group A TTLS. The Group B TTLS preactivated by curvature generated larger M/F when compared to the bend preactivation.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Early vertical correction of the deep curve of Spee

ABSTRACT Even though few technological advancements have occurred in Orthodontics recently, the search for more efficient treatments continues. This paper analyses how to accelerate and improve one of the most arduous phases of orthodontic treatment, i.e., correction of the curve of Spee. The leveling of a deep curve of Spee can happen simultaneously with the alignment phase through a method called Early Vertical Correction (EVC). This technique uses two cantilevers affixed to the initial flexible archwire. This paper describes the force system produced by EVC and how to control its side effects. The EVC can reduce treatment time in malocclusions with deep curves of Spee, by combining two phases of the therapy, which clinicians ordinarily pursue sequentially

Crimpable double tubes for segmental retraction

When a T-loop is used in segmental mechanics, it is generally attached posteriorly to an auxiliary tube in the first molars and anteriorly to a crimpable cross tube or a Burstone canine bracket. This article illustrates the use of a crimpable tube with a 90-degree bend on the base wire to secure a T-loop in segmental retraction. Both of these approaches allow a T-loop to be reactivated in a simple manner without undesirable changes in the system of forces, which could happen if the T-loop is skewed posteriorly

Welding strength of NiTi wires

ABSTRACT Objective: To identify the appropriate power level for electric welding of three commercial brands of nickel-titanium (NiTi) wires. Methods: Ninety pairs of 0.018-in and 0.017 × 0.025-in NiTi wires were divided into three groups according to their manufacturers - GI (Orthometric, Marília, Brazil), GII (3M OralCare, St. Paul, CA) and GIII (GAC,York, PA) - and welded by electrical resistance. Each group was divided into subgroups of 5 pairs of wires, in which welding was done with different power levels. In GI and GII, power levels of 2.5, 3, 3.5, 4, 4.5 and 5 were used, while in GIII 2.5, 3, 3.5 and 4 were used (each unit of power of the welding machine representing 500W). The pairs of welded wires underwent a tensile strength test on an universal testing machine until rupture and the maximum forces were recorded. Analysis of variance (ANOVA) and post-hoc tests were conducted to determine which subgroup within each brand group had the greatest resistance to rupture. Results: The 2.5 power exhibited the lowest resistance to rupture in all groups (43.75N for GI, 28.41N for GII and 47.57N for GIII) while the 4.0 power provided the highest resistance in GI and GII (97.90N and 99.61N, respectively), while in GIII (79.28N) the highest resistance was achieved with a 3.5 power welding. Conclusions: The most appropriate power for welding varied for each brand, being 4.0 for Orthometric and 3M, and 3.5 for GAC NiTi wires

Paresthesia during orthodontic treatment: case report and review.

Paresthesia of the lower lip is uncommon during orthodontic treatment. In the present case, paresthesia occurred during orthodontic leveling of an extruded mandibular left second molar. It was decided to remove this tooth from the appliance and allow it to relapse. A reanatomization was then performed by grinding. The causes and treatment options of this rare disorder are reviewed and discussed. The main cause of paresthesia during orthodontic treatment may be associated with contact between the dental roots and inferior alveolar nerve, which may be well observed on tomography scans. Treatment usually involves tooth movement in the opposite direction of the cause of the disorder

Resistência ao cisalhamento de bráquetes fotopolimerizados com arco de plasma, LED e luz halógena utilizando diferentes tempos

This study evaluated in vitro the shear bond strength of brackets bonded with xenon plasma arc light, light-emitting diode (LED) and conventional halogen light using different curing times. Brackets were bonded to the buccal surface of 60 human maxillary premolars allocated to five groups. In groups 1 and 2, the resin was cured with the plasma arc for three and six seconds (s), respectively; in groups 3 and 4, the LED was used for five and ten s, respectively; and in group 5, the halogen light was used for 40 s. The specimens were stored in water for 24 hours and subjected to a shear force until bracket failure. The debonding pattern was classified according to the adhesive remnant index (ARI). The results were assessed by Anova and the SNK post-hoc test. No differences were detected among groups 2, 4 and 5, which showed higher averages than groups 1 and 3, which were not different between themselves. The ARI scores showed no differences among the three types of light sources in all times tested. Plasma arc and LED lights can be used with shorter curing times, within certain limits, than conventional halogen light for bonding orthodontic brackets, without decreasing bond strength.Esta pesquisa avaliou in vitro a resistência ao cisalhamento de bráquetes ortodônticos fotopolimerizados com o arco de plasma, o diodo emissor de luz (LED) e a luz halógena convencional em diferentes tempos. Bráquetes foram colados em 60 pré-molares superiores humanos, divididos em cinco grupos. Nos grupos 1 e 2 utilizou-se a luz arco de plasma por três e seis segundos, respectivamente; nos grupos 3 e 4 utilizou-se o LED por cinco e dez segundos, respectivamente; no grupo 5 utilizou-se a luz halógena por 40 segundos. Os corpos de prova foram armazenados em água destilada em temperatura ambiente e, após 24 horas dos procedimentos de colagem, foram submetidos aos ensaios mecânicos na máquina universal MTS-Material Test System. Para a complementação dos resultados, também foi realizada a avaliação e a classificação do padrão de descolagem dos bráquetes utilizando o IAR. Os resultados foram analisados por meio da análise de variância (Anova, seguida do teste SNK de Tukey para comparação múltipla de médias. Não houve diferenças entre os grupos 2, 4 e 5, as quais foram maiores que as médias dos grupos 1 e 3, iguais entre si. Os escores do IAR não mostraram diferenças quanto à interface de descolagem entre os três tipos de luz em todos os tempos testados. A luz arco de plasma e o LED podem ser utilizados por tempos reduzidos, dentro de certos limites, em relação à luz halógena na colagem de bráquetes ortodônticos, sem perda de resistência ao cisalhamento

Composite pontics for orthodontic patients with extraction spaces.

Esthetic orthodontic appliances continue to appeal to more patients, which results in objections to extraction spaces that remain for several months during orthodontic therapy. This has led orthodontists to design temporary pontics that fill extraction sites and that can be reduced as the spaces close. This report describes a simple, efficient, and expeditious technique for making such pontics. © 2010 Quintessence Publishing Co, Inc