FIGURE 6.

The relationship between solutions of varying pH and the light output from both the crown and root portions of the tooth after addition of CSPa. The solutions used from point a to point L are 1% citric acid (pH 2.3, a), lemon juice (pH 2.5, b), diet cola (pH 3.1, c), apple juice (pH 3.2, d), 0.01% citric acid (pH 3.3, e), Ribena really light (pH 3.8, f), orange juice (pH 4.0, g), 0.0001% citric acid (pH 4.9, h), deionized water (pH 5.5, i), semi‐skimmed milk (pH 6.7, j), phosphate buffered saline (pH 7.2, k) and sodium hydroxide (pH 13.5, l)