IADR Abstract Archives
Kinetic Frictional Forces of 0.018-inch and 0.022-inch Slots Orthodontic Bracket in Sliding Mechanic
Objectives: This study compared kinetic frictional forces of stainless steel (SS) edgewise orthodontic bracket between 0.018-inch slot coupled with 0.017X0.025-inch SS wire and 0.022-inch slot coupled with 0.019X.025-inch SS wire in simulated sliding canine movement.
Methods: This in-vitro study was done by measuring kinetic frictional forces of samples (n=96), divided into two bracket-slot groups and each of these groups was divided into four retarding-force groups in randomized design. Kinetic frictional forces of 0.018-inch and 0.022-inch slots orthodontic bracket were measured by ChatillonTM Universal Testing Machine (crosshead speed: 1mm/min, load cell: 1kgf) in simulated sliding canine movement using 0gr, 50gr, 100gr, and 150gr retarding forces, then statistically analyzed (one way ANOVA, post hoc Bonferroni, p<0.05).
Results: The mean of kinetic frictional forces was significantly greater for the 0.018-inch than 0.022-inch bracket-slot group in the 0g (140.8gf vs. 107.3gf, p=0.001), 50g (142.1gf vs. 121.0gf, p=0.039), and 100g (200.7gf vs. 179.7gf, p=0.038) retarding-force groups, but it was not significant in the 150g (245.4gf vs. 231.0gf, p=0.742) retarding-force group. Kinetic frictional forces increased significantly along the increasing of the 50g, 100g, and 150g retarding forces (p=0.001) for both bracket-slot groups.
Conclusions: Kinetic frictional force of the 0.018-inch slot SS edgewise orthodontic bracket coupled with 0.017X0.025-inch SS wire is generally greater than the 0.022-inch slot SS edgewise orthodontic bracket coupled with 0.019X0.025-inch SS wire in sliding mechanic.
Methods: This in-vitro study was done by measuring kinetic frictional forces of samples (n=96), divided into two bracket-slot groups and each of these groups was divided into four retarding-force groups in randomized design. Kinetic frictional forces of 0.018-inch and 0.022-inch slots orthodontic bracket were measured by ChatillonTM Universal Testing Machine (crosshead speed: 1mm/min, load cell: 1kgf) in simulated sliding canine movement using 0gr, 50gr, 100gr, and 150gr retarding forces, then statistically analyzed (one way ANOVA, post hoc Bonferroni, p<0.05).
Results: The mean of kinetic frictional forces was significantly greater for the 0.018-inch than 0.022-inch bracket-slot group in the 0g (140.8gf vs. 107.3gf, p=0.001), 50g (142.1gf vs. 121.0gf, p=0.039), and 100g (200.7gf vs. 179.7gf, p=0.038) retarding-force groups, but it was not significant in the 150g (245.4gf vs. 231.0gf, p=0.742) retarding-force group. Kinetic frictional forces increased significantly along the increasing of the 50g, 100g, and 150g retarding forces (p=0.001) for both bracket-slot groups.
Conclusions: Kinetic frictional force of the 0.018-inch slot SS edgewise orthodontic bracket coupled with 0.017X0.025-inch SS wire is generally greater than the 0.022-inch slot SS edgewise orthodontic bracket coupled with 0.019X0.025-inch SS wire in sliding mechanic.