Orthodontic Elastomeric Chains Research Articles

Force decay in orthodontic elastomeric chains after immersion in disinfection solutions

Aim: To evaluate the force decay of orthodontic elastomeric chains after immersion in disinfecting solutions. Methods: One-hundred and fifty segments of elastomeric chains were divided in 3 groups: Control group – no disinfection; Chlorhexidine group - disinfection in 0.12% chlorhexidine digluconate solution; and Peracetic acid group - disinfection in 0.2% peracetic acid solution. Elastomeric chains of 14 mm were stretched up to 20 mm and the given force (kgf) was evaluated in an Instron universal testing machine at the following intervals: 1 h, 1 day, 7, 14, 21 and 28 days after the immersion in the disinfecting solutions. Data (kgf) were analyzed statistically by Analysis of Variance and Tukey’s test at a 5% significance level. Results: Both groups presented similar force decay along 7 days and remained stable up to 28 days. Force degradation was observed in the first hours of activation (~50%). Conclusions: It may be concluded that there were no significant differences among the investigated groups, in most interval times, indicating that both chemical solutions can be used for previous disinfection of orthodontic elastomeric chains.

Force decay in orthodontic elastomeric chains after immersion in disinfection solutions

Force decay in orthodontic elastomeric chains after immersion in disinfection solutions

Force decay of orthodontic elastomeric chains by using three different mechanisms simulating canine retraction

The ideal force-delivery system must: provide optimal tooth moving forces that elicit the desired effects, be comfortable and hygienic for the patient, require minimal operator manipulation and patient cooperation and provide rapid tooth movement with minimal mobility during orthodontic therapy, the elastomeric chains have the greatest potential to fulfill these requirements. Materials and Methods: This in vitro study was designed to determine the effect of three different mechanisms for canine retraction : (6-3 , 6-5-3 and chain loop ) on the load relaxation behavior of three types of elastomeric chains : (maximum clear , maximum silver and extreme silver) from the same company (Ortho Technology company) with two different brand configurations: closed loop and open (short filament) chains under effect of time at (zero time, 24hr., 7, 14 , 21 and 28 days) in artificial saliva. Results: Statistical analysis showed that there was a highly significant difference in the mean percentage force decay for the three different mechanisms (P≤ 0.001).For all the three types, the 6-3 mechanism had the smallest mean percentage force decay. There was a highly significant difference in the mean percentage force decay for the different types (P≤ 0.001). For all three mechanisms, extreme silver elastomeric chains had the smallest percentage force decay while maximum silver elastomeric chains had the highest percentage force decay. Conclusion: This study illustrated that for all the three types of elastomeric chains, the (6-3) mechanism had the smallest mean percentage force decay. This finding suggests that it may be most efficient to retract a canine utilizing elastomeric chain directly from the molar hook to the canine bracket. The chain loop mechanism may not be indicated for space closure in vivo due to the excessive physiological force values involved with this mechanism.

A systematic review of force decay in orthodontic elastomeric power chains

Elastomeric chains are one of several devices used to provide force for orthodontic tooth movement, but the force they exert diminishes over time and can thus be difficult to control. The objective of this investigation was to provide a systematic review of publications pertinent to force decay in orthodontic elastomeric chains. A systematic review was performed via electronic querying of multiple databases for the period 1970-2011. Queries were limited to a set of specific keywords in two languages (English and French). Five main reviews were consulted manually to identify relevant publications. Two investigators sorted out those studies that complied with selection criteria. A total of 53 studies were found to be relevant to force decay in elastomeric chains, including 22 on force decay over time, seven on the force consequences of pre-stretching, 12 on the impact of the environment on the force delivered, and 11 on clinical efficacy. The force delivered by elastomeric chains decays rapidly over time, affecting their mechanical properties and clinical efficacy when studied in either human saliva or laboratory test media.

The influence of simulated aging on the mechanical properties of orthodontic elastomeric chains without an intermodular link

Orthodontic elastomeric chains are a main component in orthodontic therapy with fixed vestibular or lingual appliances. The objective of this study was to investigate the influence of artificial aging on the mechanical properties of orthodontic elastomeric chains (power chains, PCs) without an intermodular link using a test setup according to DIN EN ISO 21606:2007. In this study, 11 types of PCs supplied by seven manufacturers were investigated. Four groups with 10 specimens each were randomly generated for each type. Samples were separately mounted in a universal testing machine and extended by 300% (four times their initial length) at a crosshead rate of 100 mm/min and were held at this position for five seconds. The chain length was then reduced to three times the initial length (extension by 200%) and kept for 30 s. Then, within the control group (t = 0) and the force Fmin was recorded before extension until failure was performed and force (Fmax) and length (Lmax) at failure were determined. After prestretching, specimens of the three other groups were stored in water at 37°C with its three times initial length for one day (t = 1), 14 days (t = 2), and 28 days (t = 3), respectively. The specimens were then placed in the universal testing machine and the residual force (Fmin) measured, so as to subsequently extend them until failure at Fmax and Lmax. Data were statistically analyzed by one-way analysis of variance; the level of significance was set at p = 0.05. Statistical analysis revealed significant differences in Fmax, Fmin, and Lmax in each group (t = 0 to t = 3) between the various manufacturers (p < 0.001). Moreover, artificial aging significantly influenced Fmax, Fmin, and Lmax (p < 0.001). The orthodontist should consider both the mechanical properties of PCs and the duration of these appliances' application when treating patients. Artificial aging had a significant influence on the parameters we determined (p <0.001).

Viscoelastic properties of elastomeric chains: An investigation of pigment and manufacturing effects

Orthodontic elastomeric chains are commercially available in various colors from many manufacturers. In this study, we investigated the viscoelastic properties of elastomeric chains using dynamic mechanical analysis to perform color and brand comparisons. Ten colors of Sunburst chains (GAC International, Bohemia, NY) were selected for the color study. Three colors of Sunburst, Bobbin Alastik (3M Unitek, Monrovia, Calif), and Energy (Rocky Mountain Orthodontics, Denver, Colo) chains were selected for the brand study. Nine specimens of each type were measured and tested. Dynamic mechanical analysis was performed at room temperature at 8 frequencies ranging from 0.125 to 16.0 Hz. Three variables (storage stiffness, loss stiffness, and tan δ) were analyzed by using repeated-measures analysis of variance (ANOVA) and pairwise t tests, comparing all frequencies for each specimen type and all specimen types for each frequency (with Bonferroni corrections). Significance was set at α = 0.05. Significant differences were found among all specimen dimensions, all frequencies, and all 3 dynamic mechanical analysis variables in both the color and brand studies. Comparisons focused on tan δ, which does not depend on specimen dimensions as do storage stiffness and loss stiffness. Statistically significant differences in tan δ values among colors were relatively small, so the clinical significance is questionable and requires further investigation. Differences in tan δ values among brands were greater and more likely to be clinically significant. Further studies are needed to relate viscoelastic properties to force decay.

The effects of varying alcohol concentrations commonly found in mouth rinses on the force decay of elastomeric chain

To test the effect of alcohol on force decay of elastomeric chains in vitro in order to determine if increasing alcohol concentrations results in an increased amount of elastomeric chain force decay. A prospective laboratory study was completed to test the effect of alcohol exposure on orthodontic elastomeric chain. A total of 450 specimens were divided into five test groups. Two test groups were each exposed to different alcohol concentrations (14% and 26.9%) and the other two test groups were exposed to different commercially available mouth rinses (Cēpacol -14% alcohol and Listerine - 26.9% alcohol) for 60 seconds twice a day. The control group followed all of the same procedures but was only exposed to deionized (DI) water. Force measurements were taken at six time points (initial, 1 day, 7 days, 14 days, 21 days, and 28 days). There were no significant differences among groups at the initial time point (P = .52). Statistically significant effects of time on force decay were seen in all groups. All test groups showed significantly more force decay than the control group. Only a few statistically significant differences were observed when comparing force decay among the test groups. Alcohol causes an increase in force decay of elastomeric chain over time. A concentration dependence of alcohol on force decay of elastomeric chain was not observed.

Avaliação das tensões liberadas por elásticos ortodônticos em cadeia: estudo in vitro

INTRODUÇÃO: os materiais elastoméricos são considerados importantes fontes de força para a movimentação ortodôntica. OBJETIVO: avaliar a liberação de tensões de quatro marcas comerciais de elásticos ortodônticos em cadeia (Morelli, Ormco, TP e Unitek), em função do tempo, quando mantidas tensionadas por uma força inicial de 150g e imersas em saliva artificial a 37ºC. MÉTODOS: os elásticos em cadeia foram tensionados entre pinos de aço, fixados em uma placa de resina acrílica à distância de 15mm (Morelli e TP) e de 16mm (Unitek e Ormco), ambas medidas correspondendo a uma força de 150g. A leitura da quantidade de tensão liberada pelos elásticos foi realizada com um dinamômetro nos intervalos 30 minutos, 7, 14 e 21 dias. Os dados obtidos foram submetidos à análise de variância (ANOVA) (p&lt;0,05) e ao teste de Comparações Múltiplas de Tukey. RESULTADOS: após 30 minutos de teste, verificou-se redução entre 19% e 26,67% na quantidade de tensão liberada pelos elásticos; e entre 36,67% e 57% após 21 dias de estiramento constante. CONCLUSÕES: os elásticos em cadeia que apresentaram comportamento mais estável foram os da marca TP, pois relataram menor perda de potencial elástico nos intervalos de tempo testados. Os da marca Unitek demonstraram maior redução de tensão liberada. As marcas Ormco e Morelli obtiveram resultados semelhantes entre si.

Evaluation and Comparison of The Effect of Artificial saliva and Mouthwash Solution on Force Degradation of Different Types of Orthodontic Traction Aids (Comparative in Vitro Study)

Aims: To determine the amount of force degradation of three types of orthodontic traction aid polyurethane elastomeric chain (PEC), nickel titanium closed coil spring (NiTi CCS) and stainless steel closed coil spring (SS CCS). Material and methods: Samples were extended to a specific distance which was 18 mm in case of PEC and 20 mm in case of NiTi CCS and SS CCS. Each extended sample will then incubated in dry condition, artificial saliva, and mouthwash solution, for total incubation period of three weeks. Results: showed that samples in dry condition always showed minimum force degradation percent than in wet conditions. It also showed that the increase of incubation time leads to increase in force degradation percent with major degradation percent located within first twenty four hours. Conclusions: in dry and two wet conditions, NiTi CCS reflects the lowest percent of force degradation, PEC showed highest percent, while SS CCS showed intermediate one.

Tensile Properties of Orthodontic Elastomeric Chains

Orthodontic elastomeric chains are a main component in orthodontic therapy employing labial or lingual appliances. The aim of this study was to investigate the tensile properties of orthodontic elastomeric chains with a test setup according to ISO 21606:2007. Orthodontic elastomeric chains of eight manufacturers with and without an intermodular link were obtained from commercially-available stock, yielding 23 groups with ten specimens each. Samples were mounted in a universal testing machine and extended at a rate of 100 mm/min to four times the initial length and held for 5 seconds. After 5 seconds, the chain lengths were reduced to an extension of three times the initial length and held for 30 seconds before extension until failure. Forces at four times the test length (Fmax1), three times the initial length (Fmin) as well as force (Fmax2) and length (Lmax) at failure were recorded. Data were statistically analyzed by one-way analysis of variance using SPSS® 17. The level of significance was set at p = 0.05. Statistical analysis revealed significant differences in Fmax1, Fmin, Fmax2 and Lmax among the various manufacturers. Fmax1 ranged between 9.1 N and 23.2 N, Fmin ranged between 1.5 N and 3.0 N, Fmax2 ranged between 15.7 N and 34.0 N, and Lmax ranged between 425% and 629% of the initial length. The tensile properties of different manufacturers of elastomeric orthodontic chains differ statistically significantly. Hence the amount of orthodontic force that is applied depends significantly on the type of elastomeric chains used in combination with labial or lingual appliances.

Force application and decay characteristics of untreated and treated polyurethane elastomeric chains.

In this study the effects of prestressing, environmental acidity, oxygen content, and temperature on mechanical properties were measured for three polyurethane-based orthodontic elastomeric chains. Specimens of each chain were treated for 10 and 100 days, and their mechanical properties were compared with those of the untreated specimens via stress-relaxation tests. Conditioning treatments were determined to affect the magnitude of residual load after relaxation, with the largest effect due to prestressing. Among the other variables studied, an increase in temperature of the environment appeared to significantly influence the degradation mechanism responsible for the deterioration of the mechanical properties of polyurethane elastomers (p < 0.001); acidity and oxygen content had no significant effects. Force decay profiles from the specimens were derived using a Maxwell-Weichert model consisting of springs and dashpots. This model allows the orthodontist to predict load magnitude supplied by the chain at activation and at any time during treatment.

Intraoral-Appliance Modification To Retract the Premaxilla in Patients With Bilateral Cleft Lip

Management of the protrusive premaxilla in patients with bilateral cleft lip is challenging for the reconstructive team. Several intra- and extraoral orthopedic techniques to reposition the protrusive premaxilla prior to bilateral cleft lip repair have been presented in the literature. A modification to a previously described tissue-borne palatal plate with a latex strap is presented. In the modified plate, the latex strap is replaced by an orthodontic elastomeric chain, and the chain over the prolabium is covered with soft denture liner. This appliance is effective in retracting the premaxilla, noninvasive, easy to construct and adjust, economic, well tolerated by the patient, and accepted by the parents.

Intraoral-appliance modification to retract the premaxilla in patients with bilateral cleft lip.

Management of the protrusive premaxilla in patients with bilateral cleft lip is challenging for the reconstructive team. Several intra- and extraoral orthopedic techniques to reposition the protrusive premaxilla prior to bilateral cleft lip repair have been presented in the literature. A modification to a previously described tissue-borne palatal plate with a latex strap is presented. In the modified plate, the latex strap is replaced by an orthodontic elastomeric chain, and the chain over the prolabium is covered with soft denture liner. This appliance is effective in retracting the premaxilla, noninvasive, easy to construct and adjust, economic, well tolerated by the patient, and accepted by the parents.

The use of orthodontic chain elastic for temporary intermaxillary fixation

A method of application of firm and resilient temporary intermaxillary fixation using readily available orthodontic elastomeric chain is described. Advantages lie in the time efficiency of its use, relative safety compared to tie-wiring techniques, flexibility of direction of pull, and the ease and rapidity with which it can be removed. Consideration is given to other potential uses of the material in the retention of various appliances used in orthognathic procedures.

Force reduction of orthodontic elastomeric chains after one month in the mouth: W. P. Rock, H. J. Wilson, and Susan E. FisherBr. J. Orthod. 1986;13:147-50

Force reduction of orthodontic elastomeric chains after one month in the mouth: W. P. Rock, H. J. Wilson, and Susan E. FisherBr. J. Orthod. 1986;13:147-50

Force reduction of orthodontic elastomeric chains after one month in the mouth.

The effect of ageing activated orthodontic elastomeric chains for one month in the mouth is reported. Over this period the mean value of exerted force fell by about 50 per cent of the original value. All the materials tested underwent a decrease in stiffness which contributed to a reduction in the force exerted. After a four week treatment period space closures in the range 0-5 mm were produced by the specimens tested.

A laboratory investigation of orthodontic elastomeric chains.

The dimensions and force/extension characteristics of 13 commercially available orthodontic chain elastomeric materials are reported. The relationship between force and extension was not linear over the range investigated and there were two definite transition points in the curves. Over the first linear part of the curve the two-loop specimens had stiffness values from 0.9 to 1.6 N/mm. Stiffness fell as the number of loops increased so that four-loop chains produced 0.6-1.1 N/mm. One hundred per cent extension produced forces in the 4-5 N range for most specimens. It is suggested that an extension of between 50 and 70 per cent would provide the most satisfactory orthodontic force.

Force degradation of orthodontic elastomeric chains—A product comparison study

In the last 20 years, synthetic elastic modules have been introduced to the orthodontist. However, force decay of these materials has been a clinical problem and the purpose of this project was to evaluate the force decay patterns of three commercially available elastomeric products—Ormco Power Chain II, Rocky Mountain Energy Chain, and TP Elast-O Chain—in a simulated oral environment. Thermal-cycled samples experienced less force decay over a 21-day period than samples stored at 37 ° C. Furthermore, statistical analysis confirmed that there was a highly significant difference (p < 0.01) between the mean force exerted by short modules and long modules for each material. Overall, modules producing higher initial forces (short modules) underwent less force decay after 21 days than did modules producing lower initial force values (long modules). All materials exerted 216 to 459 grams of force initially. After 21 days of simulated tooth movement, the force exerted by the elastic modules was 70 to 230 grams—a significant reduction (p < 0.001).

Relaxation of Orthodontic Elastomeric Chains and Modules In Vitro and In Vivo

Relaxation patterns for two orthodontic polyurethane-based elastics have been quantified in dry air and water bath environments and in vivo. Water bath simulation of in vivo behavior is apparently valid for up to a week following initial activation, but it becomes somewhat erroneous thereafter.