Enamel Protection of Stannous Containing Dentifrices

Objectives: Fluoride dentifrices have demonstrated efficacy for the control of acid damage to tooth enamel including caries as well as erosion. Fluoride protection against these processes may differ because of the different etiologic causes of caries and erosion (Featherstone & Lussi; Monogr Oral Sci 2006,20,1-8). OBJECTIVE: To evaluate the potential of marketed dentifrices containing various fluoride salts and concentrations to protect enamel from erosion damage due to dietary acid attack using an in vitro erosion protection model.
Methods: METHOD: Specimens were prepared from extracted human teeth, then ground and polished to provide an essentially virgin enamel surface. The enamel specimens soaked in human saliva to establish an early pellicle then were exposed to erosion cycling conditions for 5 consecutive days. Dentifrice treatments, (toothpaste/saliva), were interspersed with citric acid representing dietary acid challenges. Products compared included: I)1100ppm F (SnF₂); II)1450ppm F (SnF₂+NaF); III)1450ppm F (NaF+SnCl₂); IV)1100ppm F (NaF); V)1450ppm F (SMFP); VI)1450ppm F (SMFP+NaF); and VII)1450ppm F (SMFP+Arginine). Radiographic images were analyzed using microradiography (TMR), a computer based image analysis system. The depth of the eroded area was measured by comparing the original surface, based on the control (untreated) area, to the post treatment surface. Data is reported as mean surface loss for each treatment group.
Results: RESULTS: Specimens treated with stannous containing dentifrices demonstrated significantly less (p≤0.05) erosive damage than either NaF or SMFP treated specimens. The mean enamel surface loss (µm) for each treatment was: I)4.25(a), II)5.75(a) III) 8.25(a) > IV)17.50(b) V)17.75(b) VI)19.75(b) VII)23.75(b) (a≠b Student’s-t; p<0.05).
Conclusions: CONCLUSIONS: Results from this study demonstrate the stannous containing dentifrices provided superior protection from dietary acid challenges compared to other marketed dentifrices containing common fluoride salts. Higher fluoride concentration had no impact on a products ability to provide erosion protection. The addition of Arginine did not enhance erosion protection of SMFP in this model.