Effect of Dietary Components on Performance of Orthodontic Brackets

Objectives: This in vitro study aimed to evaluate the performance of different orthodontic brackets when exposed to various dietary components.
Methods: Metal and clear orthodontic brackets were bonded to 24 extracted second maxillary premolars (a set of 12 for each type of bracket). There were three dietary solutions (one soft drink, one energy drink and coffee) and water was used as a control solution. The bonded teeth were separated into eight groups: 3 active and one control group for each of the metal or clear brackets. The bracketed teeth were submerged for 15 minutes three times daily at different intervals to simulate an in vivo environment and were kept in water at room temperature (23°C). The Easyshade V colorimeter device was used to assess effects on tooth shading. Each recorded reading was the average of nine readings taken for each tooth immediately after immersion in the active or control solutions. Readings of the classic VITA shade and 3D VITA were recorded immediately post-bonding, after 24 and 72 hours, and 3, 7, 14, 21, and 28 days. The shear bond strength was recorded for each bracket using an ultra-tester machine. Results of the collected data were then analyzed using the unpaired t-test.
Results: As expected, no significant changes in the shade were observed for teeth immersed in water over the 4-week period. The three dietary components had a variable change in the shade of the teeth for both metal and clear brackets after four weeks of immersion. The metal brackets had a lower shear bond strength compared to clear brackets where the difference was statistically significant (P=0.01).
Conclusions: Dietary component affects the color stability of teeth with bonded brackets. Also, the clear bracket had significantly higher shear bond strength than metallic brackets after four weeks of immersion in different dietary components.