Toothbrush wear in relation to toothbrushing effectiveness

OBJECTIVE: To investigate to what extent the degree of toothbrush wear of 3‐month‐old manual toothbrushes influence plaque scores. MATERIAL AND METHODS: During a recently published study with a follow‐up of 1 year, all participants performed a similar basic home‐based oral hygiene regimen. Hence, they were instructed to brush for 2 minutes twice daily according to the Bass method technique and using a standard dentifrice containing sodium fluoride. Toothbrushes were turned in every 3‐month, and the degree of wear was scored. The mean plaque score data were additionally analysed and correlated with wear scores of the toothbrushes. RESULTS: For analysis, for each of 172 individual participants, a set of three identical, 3‐month‐old used toothbrushes were available. Toothbrush wear varied widely between participants. However, per patient, the 3‐month wear status of the three evaluated toothbrushes was strongly correlated (rho = 0.8, P < 0.0001). Participants who returned toothbrushes with extreme wear had significantly higher plaque scores than those who returned toothbrushes with no visible or light wear (P = 0.01). CONCLUSION: Toothbrush wear per individual patient is fairly consistent. Toothbrushes with extreme wear were less effective than those with no or light wear. Therefore, bristle splaying appears to be a more appropriate measure of brush replacement time then the commonly used toothbrush age. Splaying of the outer tufts beyond the base of the toothbrush is a condition that indicates it is time to change the brush.