Fluorescence-based monitoring of biomimetic and ion-releasing agents for artificial initial enamel lesions: an in vitro study

Fluorescence can monitor optical responses to interventions for initial enamel lesions but does not directly establish mineral recovery. We compared a combined 3% bioactive glass/fluoride/xylitol gel with four active formulations and a no-active-topical-agent cycling control. Forty-two extracted teeth underwent 96-hour lesion induction and allocation to six groups ( n = 7 each): R.O.C.S (G1), combined gel (G2), ClinPro (G3), Profluorid (G4), glycerol-stabilized calcium-phosphate clusters (G5), and control (G6). Daily treatments preceded the acid phase of a five-day cycle. DIAGNOdent Pen (DDP), QrayPen C ΔFmax (analyzed as |ΔFmax|) and mean ΔR, and FluoreCam lesion size were measured before and after treatment. Analyses used within-specimen reductions, Welch tests, Games–Howell comparisons and an exploratory repeated-profile multivariate model. Mean ± SD DIAGNOdent Pen (DDP) reductions ranged from 12.24 ± 0.76 to 14.67 ± 3.81 in G1–G5 versus 0.33 ± 1.67 in G6 ( n = 7/group); all active–control comparisons were significant (adjusted p ≤ 0.004). QrayPen C |ΔFmax| reductions were 14.29 ± 4.16 in G2 and 16.31 ± 8.50 in G5 versus 0.99 ± 1.48 in G6; the G2–G6 difference was 13.30 (95% simultaneous CI 7.10–19.50). G1 did not differ from G6. QrayPen C mean ΔR reductions were 63.29 ± 7.43 in G2 and 60.71 ± 4.64 in G5 versus 36.33 ± 12.64 in G6; only G2 and G5 differed from G6. FluoreCam reduction was 1.75 ± 1.13 in G2 versus 0.43 ± 0.83 in G6, but the adjusted difference was not significant (1.32; 95% CI − 0.49 to 3.12; p = 0.209). (1) Optical responses were endpoint-specific, without consistent superiority of one formulation. (2) Findings concern complete formulations, not isolated bioactive glass.