Investigation of the Mechanical Properties of Different Clear Aligner Materials

Öz

Aim: In order for the clear aligner treatment to be successful, the aligner material must provide sufficient orthodontic force to make the desired tooth movements without damaging the surrounding periodontal tissues. It is known that the mechanical properties of the material of the clear aligners have a critical role in the orthodontic force produced. In this study, it is aimed to determine the changes in the mechanical properties of different aligner materials that may affect the orthodontic force and to examine their effects.

Method: In this study, tensile tests were performed in accordance with the relevant standards in order to determine the mechanical properties of 6 different clear aligner materials (CA Pro, GT Flex, Zendura Flex, Zendura, Taglus, GT Pro). From the tensile test results, the parameters of the elastic modulus, tensile strength and elongation at break were obtained, as well as the stress-strain curves of the materials. The results were statistically evaluated and the mechanical properties of the materials were interpreted.

Results: According to material types, elastic modulus, tensile strength and elongation at break measurements showed statistically significant differences (p=0.001; p<0.01). When the paired comparisons were evaluated, it was determined that the Zendura Flex material had the lowest elastic modulus and tensile strength value, which was statistically significant.

Conclusion: According to the results of this study, the multilayered Zendura Flex and CA Pro materials showed the lowest elastic modulus and the lowest tensile strength values to support this result. The results of this study supported that different clear aligner materials show different mechanical properties. In order to increase the success of clear aligner treatment, it has been predicted that proper aligner materials can be determined with a good knowledge of the mechanical properties of aligner materials.

Anahtar Kelimeler

• Clear aligners
• mechanical properties
• elastic modulus
• Ortodonti
• poliüretanlar
• esneklik

Farklı Şeffaf Plak Materyallerinin Mekanik Özelliklerinin Araştırılması

Öz

Amaç: Şeffaf plak tedavisinin başarılı olabilmesi için, plak materyalinin çevre periodontal dokulara zarar vermeden istenilen diş hareketlerini yaptırabilecek yeterli ortodontik kuvveti sağlaması gerekmektedir. Şeffaf plakların malzemesinin mekanik özellikleri üretilen ortodontik kuvvet için kritik bir role sahip olduğu bilinmektedir. Bu çalışmada, farklı şeffaf plak materyallerinin ortodontik kuvveti etkileyebilecek mekanik özelliklerinin değişimlerinin tespiti ve etkilerinin incelenmesi amaçlanmıştır. Bu çalışmanın sıfır hipotezi, termoplastik malzemelerden elde edilmiş farklı şeffaf plak materyallerinin farklı mekanik özellikler göstermesi sebebiyle CA Pro, GT Flex, Zendura Flex, Zendura, Taglus ve GT Pro plak materyallerinin mekanik özelliklerinin incelenmesidir.

Yöntem: Çalışmada 6 farklı şeffaf plak materyalinin (CA Pro, GT Flex, Zendura Flex, Zendura, Taglus, GT Pro) mekanik özelliklerini belirlemek amacıyla ilgili standartlara uygun olarak çekme deneyleri yapılmıştır. Çekme deneyi sonuçlarından materyellerin gerilme uzama eğrilerinin yanında elastisite modülü, çekme dayanımı ve kopma uzaması parametreleri elde edilmiştir. Sonuçlar istastiksel olarak değerlendirilmiş ve materyallerin mekanik özellikleri yorumlanmıştır.

Bulgular: Materyal türlerine göre elastisite modülü, çekme dayanımı ve kopma uzaması ölçümleri istatistiksel olarak anlamlı farklılık göstermiştir (p=0,001; p<0,01). Yapılan ikili karşılaştırmalar değerlendirildiğinde en düşük elastisite modülü ve çekme dayanımı değerine Zendura Flex materyalinin sahip olmasının istatistiksel olarak anlamlı olduğu tespit edilmiştir.

Sonuç: Çalışmanın sonuçlarına göre çok katmanlı yapıda olan Zendura Flex ve CA Pro materyalleri, en düşük elastisite modülü ve bu sonucu destekleyecek şekilde en düşük çekme dayanımı değerleri göstermiştir. Çalışmanın sonuçları farklı şeffaf plak materyallerinin farklı mekanik özellikler gösterdiğini desteklemiştir. Şeffaf plak tedavisinin başarısını arttırmak amacıyla plak materyalleri mekanik özelliklerinin iyi bilinmesi ile uygun plak materyallerinin belirlenebileceği öngörülmüştür.

Anahtar Kelimeler

• Ortodonti
• poliüretanlar
• esneklik

Kaynakça

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