OBJECTIVE: This study evaluated Sodium Fluoride mouth rinse effects on elastic properties of different elastomeric chains. STUDY DESIGN: In this in vitro experiment, two orthodontic chains were tested. In the first group, they were stored in artificial saliva for the entire duration, and in the second group they were immersed daily in 0.05% NaF mouth rinse for 1 minute, artificial saliva-NaF mixture for 30 minutes, and then in artificial saliva for the rest of the day. Specimens were tested at baseline, 1 hour 24 hours, 1, 2 and 3 weeks and then the displacement of specimens to obtain 150 g and 300 g, also the applied force after stretching them to 100% of their original length were evaluated. RESULTS: In contrast to force degradation, chains of both companies required more displacement to achieve both forces in the saliva-NaF mixture than saliva itself however the difference was only significant for the 300g force (P = 0.020). American Orthodontics chains required more displacement than Dentaurum chains to obtain both forces, also they had more load relaxation (P < 0.001). CONCLUSIONS: Daily use of NaF mouth rinse does not affect force degradation and the displacement of both chains to achieve conventional orthodontic forces, but for higher force levels the displacement increase is statistically significant.
OBJECTIVE: This study evaluated Sodium Fluoride mouth rinse effects on elastic properties of different elastomeric chains. STUDY DESIGN: In this in vitro experiment, two orthodontic chains were tested. In the first group, they were stored in artificial saliva for the entire duration, and in the second group they were immersed daily in 0.05% NaF mouth rinse for 1 minute, artificial saliva-NaF mixture for 30 minutes, and then in artificial saliva for the rest of the day. Specimens were tested at baseline, 1 hour 24 hours, 1, 2 and 3 weeks and then the displacement of specimens to obtain 150 g and 300 g, also the applied force after stretching them to 100% of their original length were evaluated. RESULTS: In contrast to force degradation, chains of both companies required more displacement to achieve both forces in the saliva-NaF mixture than saliva itself however the difference was only significant for the 300g force (P = 0.020). American Orthodontics chains required more displacement than Dentaurum chains to obtain both forces, also they had more load relaxation (P < 0.001). CONCLUSIONS: Daily use of NaF mouth rinse does not affect force degradation and the displacement of both chains to achieve conventional orthodontic forces, but for higher force levels the displacement increase is statistically significant.