Remineralizing Efficacy of Different Calcium-phosphate and Fluoride Based Delivery Vehicles on Artificial Caries Like Enamel Lesions

Objectives: To assess enamel remineralization of different calcium-phosphate and fluoride delivery systems.

Methods: Artificial caries lesions were created on 115 extracted human molars. Specimens were assigned according to remineralizing agent into five groups: G1: Control (artificial saliva), G2: Clinpro™ white varnish, G3: Relief, G4: Tooth Mousse Plus, G5: Vanish™XT. Surface micro-hardness (SMH), surface roughness (Ra) and surface topography by scanning electron microscope (SEM) were evaluated at baseline, after demineralization, after 2 and 4 weeks remineralization and after acid challenge.

Results: Demineralized enamel showed the lowest SMH. By 2 weeks remineralization, SMH were ranked as follows: G2 (282.14±6.82)>G3 (269.37±7.25)>G5 (263.00±6.49)=G4 (251.83±8.26)>G1 (226.5±9.34). However, 4 weeks remineralization showed the following: G2 (304.09±6.65)>G3 (293.1±5.24)=G4 (285±7.29)>G5 (272.43±4.89)>G1 (233.33±9.12). By exposure to acid challenge, groups presented order of: G2 (279.71±5.99)=G3 (275.51±5.59)>G4 (262.29±6.65)>G5 (245.43±6.43)>G1 (190.27±8). Surface roughness showed the following mattress after 2 weeks remineralization: G1 (0.2488±0.0016)=G2 (0.2487±0.0007)=G3 (0.2476±0.0006)>G4 (0.2442±0.0004)>G5 (0.2396±0.0009). After 4 weeks remineralization: G1 (0.2469±0.0017)>G4 (0.244±0.0004)>G5 (0.2413±0.0008)=G3 (0.2405±0.0007)=G2 (0.2399±0.0006). After acid challenge; G1 (0.2582±0.0027)>G5 (0.2556±0.0007)>G4 (0.2484±0.0009)>G3 (0.2463±0.0007)>G2 (0.2443±0.0004). SEM revealed mineralized coating on the surfaces which resists dissolution by acid challenge at variable degrees according to remineralization regimen applied.

Conclusions: Remineralizing agents containing different calcium-phosphate formulas and fluoride have increased remineralization potential compared to artificial saliva. Clinpro™ varnish presented the highest remineralization tendency with greatest resistance for acid challenge.

Clinical Significance: This in vitro study imitated the application of different calcium phosphorous and fluoride based delivery vehicles to enamel tooth surfaces in the mouth. The new therapeutic techniques based on different calcium phosphate formulas containing fluoride provide a new avenue for remineralization of non-cavitated and early carious lesions.