Description of a new laboratory evaluation method of interdental brush abrasion as a clinical hazard

Objectives: To simulate the abrasive potential of an interdental brush when applied with toothpastes and prophylactic gels/solutions in a novel laboratory brushing simulation set-up. Methods: A brushing device was customized to treat dentin samples mimicking a simplified interdental space with an interdental brush (ISO 2). The brushing, that is, 7200 strokes for 1 h, was performed with artificial saliva (control), a povidone-iodine solution, and slurries of chlorhexidine and fluoride gels as well as three toothpastes with different RDA values ranging from 29 to 100, respectively. The loss of dentin was profilometrically assessed and compared with ANOVA and Fishers LSD. Results: While artificial saliva as control, the solution and the gel slurries showed no measurable dentin loss, toothpastes resulted in a measurable linear surface damage with respect to the actual intrinsic RDA values and ranged from 12.6 to 26.5 mu m (p < 0.001). Conclusions: Any interdental cleaning product should be tailored and carefully instructed. Any over- and misuse should be avoided, which applies especially to the use of interdental brushes in combination with abrasive toothpastes.