Comparative study of frictional forces generated by NiTi archwire deformation in different orthodontic brackets: In vitro evaluation

Abstract

Introduction:The purpose of this study was to compare the frictional forces between 0.014-in NiTi wires (Aditek) with 4 mm horizontal deflection and brackets with different archwire ligation systems. Methods:Four types of self-ligating brackets (Damon MX, Easy Clip, Smart Clip and In-Ovation), a triple bracket (Synergy) and a twin bracket with 8-shaped ligature (Tecnident) were tested. Twin brackets with conventional elastomeric ligatures (Morelli) were used as control group. Tests were repeated 10 times for each bracket/archwire combination. Frictional forces were measured in an Instron universal tensile machine at 3 mm/minute speed and a total displacement of 6 mm. Statistical analysis comprised ANOVA and Dunnett's multiple comparison post hoc test.Results: Deflection-induced frictional (DIF) forces increased in the following order: Synergy, Damon, 8-shaped Ligature, Easy Clip, In-Ovation, Smart-Clip and conventional ligatures. The differences among groups were significant, with the exception of the 8-shaped ligature groups which was equal to the Damon and Easy Clip groups. Conclusions:Compared to conventional ligatures, all ligation systems tested reduced frictional forces. However, such reduction varied according to the ligation system employed.

Resistance to sliding in orthodontics: misconception or method error? A systematic review and a proposal of a test protocol

“…Furthermore, it should be considered that RS can be both of the static and dynamic types and respective evaluation methods based on peak forces 22 30 or displacements 22 30 should be used to discriminate between the two. Simple averages of the data as performed in some studies 31 32 33 34 or unclear attribution of the values to either static or dynamic friction 16 21 25 28 35 36 37 38 39 40 41 42 43 44 may lead to oversimplifications.…”

“…Therefore, especially when super-elastic NiTi wires were tested, it was not clear whether wire curvature, e.g., the pre-formed U-shape, was taken into consideration. 16 22 23 24 25 28 30 31 34 39 43 47 50 51 52 53 54 Moreover, the wire form has obvious consequences on RS, including changes in the normal force and critical contact angles, especially in the first order 3 48 ( Figure 1 ).…”

Evaluation of Frictional Forces between Different Aesthetic Brackets and Arch Wires during Leveling and Alignment Stage

“…(3,4) Determining the approximate magnitude of frictional force associated with those esthetic and self-ligating brackets in diff erent clinical situations can assist in identifying the actual force employed in moving teeth, thus enabling the orthodontists apply light forces to the periodontium while stimulating maximal biological forces in the tooth being moved and minimal bone remodeling in the anchorage teeth. (5) In most previous studies, (4,6,7,8,9) there were limitations in study design because they investigated nonleveled brackets only, nonaligned brackets only or dealt with both malalignments separately, in addition, most of them investigated metal brackets only. Just one study has included both non leveled and non aligned brackets simultaneously to measure frictional forces.…”

Avaliação da força gerada pela deflexão gradual de fios ortodônticos em braquetes convencionais metálicos, estéticos e autoligáveis

“…Ao relacionarmos a deflexão gradual, testada no estudo citado acima (PETERSEN et al, 2009), com a resistência friccional, testada em inúmeros trabalhos presentes na literatura (O'REILLY et al, 1999;OGATA et al, 1996), observa-se que há uma concordância entre os seus resultados, uma vez que, os autores observam uma maior força de atrito nas combinações dos fio com os braquetes convencionais do que com os autoligáveis (KRISHNAN; KALATHIL; ABRAHAM, 2009;QUEIROZ et al, 2012;HUANG et al, 2012;KHALID;JAYARAM, 2012;PACHECO et al, 2011;VOUDOURIS, 1997;FERRARI et al, 2011).…”