Measurement of the cariogenicity of snacks using a radioisotope PAHA disc.

Objectives: This study aimed to establish a method for measuring the cariogenic potential of foods with high reproducibility in vitro.

Methods: Streptococcus mutans (S. mutans) was incubated in test foods with radioisotope polyacrylamide hydroxyapatite (PAHA) for 150 min at 37 °C. Then, the amount of radioisotope (32)P released from PAHA was measured using a liquid scintillation counter and scanning electron microscopy (SEM).

Results: The radioisotope PAHA discs that were soaked in 10% sucrose solutions had a high cariogenic potential and showed a remarkably demineralized surface (p < 0.05). The radioisotope PAHA disc that was incubated with snacks that had a high cariogenic potential showed a remarkably demineralized surface via SEM. Candy had a relatively high cariogenic potential, whereas xylitol gum had a relatively low potential.

Conclusions: The cariogenicity of snacks can easily be evaluated by measuring the amount of (32)P released from radioisotope PAHA discs.