Effect of fluoride sustained slow-releasing device on fluoride, phosphate and calcium levels in plaque biofilms over time measured using ion chromatography

Objectives

To determine whether there are any differences in fluoride (F), calcium (Ca) or phosphate (PO₄) concentrations in natural plaque biofilms between the upper right and left quadrants using a fluoride sustained slow-releasing device (FSSRD) placed in the upper right quadrant after 7 and 21 days. To report and validate a new methodology in measuring very low concentrations of F in dental plaque and saliva using ion chromatography.

Methods

Twenty-one participants were divided into two groups with 11 participants in group one and 10 in group two. Each participant had a FSSRD attached to the upper right second permanent molar and two plaque generating devices (PGDs) attached to the upper right and left first permanent molars. The PGDs were recovered after 7 days in group one and 21 days in group two.

Results

At both 7 and 21 days (right, left), F (1.081 ± 1.517 ppm, 0.736 ± 0.840 ppm) and (0.459 ± 0.888 ppm, 0.203 ± 0.139 ppm), PO₄ (1053 ± 533 ppm, 654 ± 246 ppm) and (865 ± 1099 ppm, 474 ± 304 ppm) and Ca (136 ± 132 ppm, 74 ± 36 ppm) and (130 ± 109 ppm, 77 ± 24 ppm), were higher in the quadrant containing the FSSRD but not significantly so (p > 0.05). Fluoride and PO₄ fell in both quadrants between 7 and 21 days, though not significantly.

Conclusions

Intriguingly while not statistically significant, 21 day plaque contained less fluoride than those investigated after 7 days. While the data was not statistically significant, it seems possible that F, Ca and PO₄ accumulated around the device to a limited extent but were washed away fairly quickly and distributed around the oral cavity.

Clinical importance

The FSSRD was found to reduce dmfs/DMFS by 76% and raise salivary F levels by ～10 folds. This device is very helpful in reducing dental decay where compliance is impaired such as in patients with special needs. This study further investigates the anti-cariogenic effect of this device.