Comparison of Dental Flosses – An Investigation of Mechanical Properties and Subjective Preference

Abstract

Abstract Objective To investigate the properties (tensile strength, roughness, abrasiveness) of different dental flosses and how these properties relate to subjective preference for floss by users. Materials and method Four flosses of differing compositions were selected (polytetrafluoroethylene, nylon, silk, and ultra-high-molecular-weight polyethylene). Tensile strength (TS) was measured utilising a universal testing machine (n = 10/group). Surface roughness (Ra) was measured on 3D reconstructed models of scanning electron microscope (n = 5/group). Abrasiveness was measured through block-on-ring tests against human enamel (n = 3/group). Subjective preference for floss was measured by asking a sample of 16 individuals to use each floss for an 8 day period using a split-mouth design. Results Highest TS was found in ultra-high-molecular-weight polyethylene floss (194.18 \(\pm\) 24.61 MPa) while the lowest TS was found in polytetrafluoroethylene floss (11.78 \(\pm\) 0.77 MPa). Silk floss had the highest Ra (0.304 \(\pm\) 0.025 µm) while polytetrafluoroethylene floss had the lowest (0.048 \(\pm\) 0.003 µm). In-vitro abrasion testing of the flosses identified in no significant differences between the flosses in causing wear on tooth enamel. Subjective ratings of flosses indicated polytetrafluoroethylene floss to be most preferred and nylon floss to be least preferred. Conclusion Polytetrafluoroethylene was rated more highly by participants than the other floss types. This floss had the lowest surface roughness and the lowest tensile strength. Clinical Relevance: This is the first study to comprehensively compare a wide range of mechanical properties of commercially available dental floss and the results of this study can provide guidance for the recommendation of dental floss for oral hygiene routines