In vitro evidence that Antiretroviral Therapy (ART) enhances protection against dental erosion in People Living with HIV (PLHIV) and individuals on Pre-Exposure Prophylaxis (PrEP)

Objective

This study aimed to evaluate the protective capacity of the salivary pellicle in people living with HIV (PLHIV) on antiretroviral therapy (ART) and individuals on pre-exposure prophylaxis (PrEP) for HIV.

Material and methods

Sixteen participants were divided into three groups: Control (n = 5; HIV-negative, not on ART), HIV (n = 7; PLHIV on ART), and PrEP (n = 4; HIV-negative, on PrEP). Stimulated saliva samples were pooled for each group. Enamel specimens (n = 45) were polished and allocated among the groups. Samples underwent five cycles of enamel pellicle formation (120 µL saliva, 37°C, 2 h), each followed by an erosive challenge (6 ml of 1 % citric acid, 25°C, 1 min, pH 3.6). Surface hardness (SH), surface reflection intensity (SRI), surface roughness (Sa), and calcium release (CaR) were measured before and after the erosive cycles. Statistical analyses included the Kolmogorov–Smirnov test for normality, one-way ANOVA for SH and SRI, and Kruskal–Wallis tests for Sa and CaR (α = 0.05).

Results

PrEP individuals exhibited the greatest protection against erosion in terms of SH, followed by PLHIV (p = 0.016). Both groups showed significantly better protection than the Control group, with higher SRI values (p < 0.05) and lower enamel surface roughness (p = 0.001). No significant differences were observed among the groups regarding calcium release (p > 0.05).

Conclusion

PLHIV and individuals on PrEP demonstrate enhanced protective properties of the salivary pellicle against dental erosion.