Deformation of elastomeric chains related to the amount and time of stretching

Yagura, Denise; Baggio, Paulo; Carreiro, Luiz Sérgio; Takahashi, Ricardo H. C.

doi:10.1590/s2176-94512013000300022

Cited by 14 publications

(17 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As shown in Figure 3C , the permanent deformation immediately after prestretch was positively correlated with the degree of prestretch, whereas no such correlation was observed when time condition was included ( Figure 3B ). Permanent deformation was positively correlated only with the constant strain set at the beginning of the experiment ( Figure 3D ), in agreement with the results of Yagura et al, 10 who found that permanent deformation was proportional to the stretching extent. Therefore, orthodontic synthetic elastomeric chains with properties altered by prestretch did not increase permanent deformation at weeks 4 and 8 during proper orthodontic treatment.…”

Section: Discussionsupporting

confidence: 91%

“…Herein, we measured length changes every week, revealing that the degree of permanent deformation was less than that observed by Song and Kim, 17 which was thought to reflect the differences in the utilized materials. The curved form of the graph reflecting the temporal evolution of normalized permanent strain ( g X ( t )) was consistent with the results obtained by Yagura et al 10 Herein, permanent deformation was found to be proportional to the stretching extent ( Figure 3D ). In addition, the highest percentage of permanent deformation was observed during the first week, which agreed with the decrease of the large early-stage permanent deformation with time.…”

Section: Discussionsupporting

confidence: 90%

See 1 more Smart Citation

Effects of prestretch on stress relaxation and permanent deformation of orthodontic synthetic elastomeric chains

et al. 2018

View full text Add to dashboard Cite

ObjectiveThis study was performed to investigate an appropriate degree of prestretch for orthodontic synthetic elastomeric chains focusing on time-dependent viscoelastic properties.MethodsOrthodontic synthetic elastomeric chains of two brands were prestretched to 50, 100, 150, and 200% of the original length in one and three cycles, and the hysteresis areas of the obtained stress-strain curves were determined. Acrylic plates were employed to maintain constant strain during the experiment. A total of 180 samples were classified into nine groups according to brand, and their stresses and permanent deformations were measured immediately after prestretch (0 hour), after 1 hour and 24 hours, and after 1, 2, 3, 4, 5, 6, 7, and 8 weeks. The relationship between stress relaxation and permanent deformation was investigated for various degrees of prestretch, and the estimated stress resulting from tooth movement was calculated.ResultsThe degree of prestretch and the stress relaxation ratio exhibited a strong negative correlation, whereas no correlation was found between the degree of prestretch and the average normalized permanent strain. The maximal estimated stress was observed when prestretch was performed in three cycles to 200% of the original length.ConclusionsAlthough prestretch benefited residual stress, it did not exhibit negative effects such as permanent deformation. The maximal estimated stress was observed at the maximal prestretch, but the difference between prestretch and control groups decreased with time. In general, higher residual stresses were observed for product B than for product A, but this difference was not clinically significant.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionsupporting

confidence: 90%

Effects of prestretch on stress relaxation and permanent deformation of orthodontic synthetic elastomeric chains

et al. 2018

View full text Add to dashboard Cite

show abstract

“…[4,9] The results of research conducted are consistent with research conducted by Mirhashemi et al where the decrease in strength after the first 24 h occurred at 20.7%-31.2% in elastomeric chains of thermoplastic materials and 9.3%-12.4% in elastomeric chains of thermoset materials. [5,8] The greatest decrease in strength that occurs after the first 24 h is also in accordance with the research conducted by Yagura et al, [10] where the greater the initial strength given to elastomeric chains, the greater the decrease in strength that occurs. Buchmann et al [3] and Mirhashemi et al [8] suggested that the decrease in strength up to the seventh day was caused by absorption of saliva and formation, which coincided with hydrogen adhesion between water molecules and elastomeric macromolecules.…”

Section: Discussionsupporting

confidence: 89%

Thermoset and thermoplastic elastomeric chain comparative strength: An in vitro study

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Elastomers are considered important adjuvant materials in orthodontic treatment and have many clinical applications 1,2 . This refers especially to esthetic elastomers used in adult patients who are highly demanding about the esthetic appearance of orthodontic appliances 3,4 .…”

Section: Introductionmentioning

confidence: 99%

Evaluation of degradation of force of esthetic elastomeric chains

Lucindo

Carneiro

Souza

et al. 2019

Rev. odontol. UNESP

View full text Add to dashboard Cite

Introduction Elastomers are considered important allies to orthodontic treatment and due to the aesthetic demand, aesthetic elastomers are increasingly used in adult patients. Objective The aim of this experimental in vitro study was to evaluate the degradation of force of esthetic elastomeric chains, of three different sizes: short, medium and long. Material and method For evaluating the degradation of force, 90 elastomeric chain segments were used, divided into 9 Groups (n=10), as follows: Morelli short elastomer, Morelli medium, Morelli long, Orthometric short, Orthometric medium, Orthometric long, American Orthodontic short, American Orthodontic medium and American Orthodontic long. Acrylic plates with pins were used to provide stretching of the elastomeric chains. The initial stretching force of the elastomeric chain was 150 grams, measured by a tensiometer. After this, they were prestretched to 50% of their original length, measured in an Instron 4411 Universal test machine, and placed on the seating pin on the plate. The plate was immersed in artificial saliva at 37 °C in a plastic receptacle, and removed for measurement after a time interval of 21 days. For statistical analysis, the methodology of mixed models for repeated measures in time and Tukey-Kramer test were used. Degradation of the forces was analyzed by 2-way analysis of variance (ANOVA) and the Tukey test. Result All the elastomeric chains showed statistically significant reduction in force (p<0.05). The American Orthodontic elastomeric chains showed higher reduction in force values, irrespective of the elastic size (p<0.05). Conclusion The three commercial brands studied underwent significant reduction in the quantity of force released; the American Orthodontic brand of elastomer showed the highest value of degradation in force.

show abstract

Deformation of elastomeric chains related to the amount and time of stretching

Cited by 14 publications

References 11 publications

Effects of prestretch on stress relaxation and permanent deformation of orthodontic synthetic elastomeric chains

Effects of prestretch on stress relaxation and permanent deformation of orthodontic synthetic elastomeric chains

Thermoset and thermoplastic elastomeric chain comparative strength: An in vitro study

Evaluation of degradation of force of esthetic elastomeric chains

Contact Info

Product

Resources

About