CPP-ACP paste's effect on salivary conditions in patients with removable dentures

Older adults with removable dentures experience high rates of both caries (when the natural dentition remains) and salivary gland dysfunction. While many commercial dental therapeutic agents target these two interrelated problems, none have been labeled for use on the fitting surface of removable dentures. Off-label use of MI Paste (GC America, Alsip, IL), a dental therapeutic containing casein-phosphopeptide-amorphous-calcium-phosphate (CPP-ACP), was investigated following its application to the fitting surface of complete denture(s) with subsequent effects on salivary conditions measured.

Salivary flow rate and pH were recorded at baseline and 15 min following the application of 1 mL of CPP-ACP paste to the fitting surface of each participant's denture through whole saliva collection. To assess buffering capacity, equivalent volumes of 0.01 M lactic acid were added to the collected saliva samples, and pH reduction was measured. Comparisons of salivary parameters between baseline and post-CPP-ACP paste application and between subjects with and without self-reported xerostomia were conducted using a paired-sample t-test, Wilcoxon signed-rank test, or two-sample t-test as appropriate.

Of the 28 participants (mean age = 70.3 ± 13.7 years, 17 males), 11 reported xerostomia. CPP-ACP-paste application was associated with decreased pH reduction during acid challenge compared to baseline (0.95 ± 0.24 vs. 1.54 ± 0.53, p < 0.001), and a higher final pH following acid challenge (5.93 ± 0.34 vs. 5.40 ± 0.66, p < 0.001). While the flow rates observed at post-CPP-ACP paste application were greater than those at baseline, the difference was not statistically significant (0.67 ± 0.44 mL/min vs. 0.55 ± 0.34 mL/min, p = 0.053). No significant differences were found in any salivary parameters between participants with or without self-reports of xerostomia.

The findings highlight potential positive effects on salivary conditions following the application of the CPP-ACP-containing product, MI Paste, to the fitting surface of a removable complete denture as a potential caries-risk-management tool when natural dentition remains. Determining the caries-preventive clinical significance will require longer-term trials.