Objective: To demonstrate that a brush, re-engineered with softer bristles, retains the ability to clean effectively and reach the back teeth. Method: The study was a randomised two product cross-over design comprising of 5 visits over two weeks by 38 subjects. At visit 1, subjects were randomly allocated either Brush 1 (a brush designed to allow easy access to the back teeth) or Brush 2 (brush 1 with re-engineered trim and softer bristles) to use at home for at least 4 days before visit 2. At visit 2, subjects refrained from brushing for 24hrs and had their plaque assessed before (PRE) and after brushing (POST) with their allocated brush using modified Navy index (MNI). Subjects continued brushing with their allocated brush at home until visit 3, when the OralInsights system (OIS) was used to record their brushing behaviour. The second test brush was subsequently allocated and the same procedures at visits 2 and 3 were repeated at visit 4 and 5, respectively. Results: Mean POST plaque scores, for whole-mouth, interproximal and gum-line regions were statistically significantly lower than the mean PRE scores, (p<0.0001) for both brushes. The differences between the two brushes in PRE/POST plaque reductions were 2% whole mouth 3% at the interproximal sites and 2% at the gum line. The OIS recorded mean brushing times of 86.1seconds (s.d.=40.9) and 84.9seconds (s.d.=37.5) for Brushes 1 and 2, respectively. The OIS measured the proportion of time spent brushing the back teeth as 55.1% for Brush 1 and 54.8% for Brush 2. Equivalence tests gave no significant differences between Brushes 1 and 2 in terms of plaque score, brushing times or percentage of time spent brushing different areas of the mouth. Conclusions: Brushes 1 and 2 were equally as effective at plaque removal and reaching the back teeth.