This study evaluated the brushing efficacy of different interdental brushes around a multibracket appliance in vitro. In four models displaying misaligned and aligned teeth with and without attachment loss, the brushing capacities of three interdental brushes (IDB) were tested: A waist-shaped IDB with a diameter of 9 mm at both ends and 5 mm in the middle (B1), a cylindrical brush with a diameter of 9 mm (B2) and one with 5 mm (B3). Before cleaning, the black teeth in the respective models were stained white with titanium (IV) oxide and the percentage of cleaned surface was planimetrically assessed. In addition, the forces applied to the IDB were also recorded. The effect of brush and model on expected cleaning performance was examined using an analysis of variance (ANOVA). The cleaning performance of the brushes in decreasing order was B2>B3>B1; no significant differences between the different tooth areas and models were found. With regard to force measurements, significant differences were found with the highest and lowest forces IDB (2) and (1), respectively. There was a significant correlation between force and cleaning performance: The higher the force needed the higher was the cleaning performance. In summary, this study showed that cylindrical interdental brushes achieved a better cleaning performance than the waist-shaped IDB. Given some shortcomings of this first laboratory study, more research is still needed, but IDB may represent a valuable yet still clinically underused tools.
Keywords: Orthodontics; in vitro test; oral hygiene; orthodontic bracket; plaque.