The Ribbon Is an Advertisement: Tube Life and Fluoride Dose at Pea-Sized Dispensing

This study examines a practical question in everyday hygiene by explicit arithmetic from stated assumptions. A 100 g tube lasted 22.7 days at the ribbon dose and 100 days at the adult pea dose, a 4.4 fold difference. Annual cost per adult was USD 56.28 against USD 12.78, and for a household of two adults and two children the combined saving was USD 38.4 per year. Modelled fluoride delivered per brushing was 3.19 mg at the ribbon and 0.72 mg at the pea dose, while the amount a young child could swallow fell from 1.28 mg to 0.2 mg per brushing at the child dose. Reducing the tube aperture diameter by 52% produced the pea dose under the same squeeze in the model. The proposed arrangement is as follows. The proposed design is disarmingly small: a printed pea outline on the brush handle or a reduced tube aperture that makes the advertised ribbon physically awkward to dispense. The study sizes the aperture reduction by the dose ratio and reports the household saving at family scale. All results are derived from the accompanying simulation script, in which every assumption appears as a named, replaceable value. SIMULATED, NOT MEASURED.