Effect of CPP-ACP on Demineralization of Enamel and Dentin

Objectives: The aim of this study was to determine the in vitro effect of GC Tooth Mousse™ and GC MI Paste Plus™ (GC) on demineralization of human enamel and root dentin in comparison to Elmex™ Caries Protection (GABA) and Sensodyne™ Pronamel™ (GlaxoSmithKline). Methods: 120 specimens of enamel [E] and 120 specimens of root dentin [D] were exposed to demineralizing solution (0.1M Na-acetate-buffer pH4.9 in 6%HEC). Immediately before and during lesion formation 20 specimens each were rinsed in one of four toothpaste slurries (15g paste in 30ml Aqua) for 3 minutes twice a day resulting in 4 test groups for [E] and [D] respectively: TM – Tooth Mousse containing CPP-ACP; TMP – MI Paste Plus containing CPP-ACP and 900ppm F; E – Elmex containing 1400ppm F; S – Sensodyne containing 1450ppm F. Further 20 enamel and dentin specimens were rinsed in Aqua instead of paste slurry (control groups A[E] and A[D]). Remaining 20 specimens each were demineralized without any further treatment (control groups C[E] and C[D]). Longitudinal sections were taken through the carious lesions and the lesion depth was estimated (polarized light microscopy). Results: 1. Deepest lesions were found in control groups: C[E] 111±23, C(D) 163±10 and A[E]99±18µm, A[D]  166±10µm; 2. Slight reduction of lesion depth was detectable for all TM/TMP-groups: TM[E] 86±14µm; TM[D]  156±9µm^* and TMP[E] 80±14µm^*; TMP[D] 153±8µm^** (^*significant p≤0.01 compared to A[E]/A[D]); 3. Highly significant (p≤0.001) reduction of lesion depth was estimated for E/S-groups: E[E] 63±14µm, E[D] 109±14µm and S[E] 58±25µm, S[D] 87±10µm compared to control groups; 4. Reduction of lesion depth in E/S-groups was significant in enamel and highly significant in dentin compared to TM/TMP-groups. Conclusions: Under the given experimental conditions the presence of 1400ppm fluoride in dentifrices was more influential on prevention of enamel and dentin demineralization than CPP-ACP paste without or with 900ppm fluoride.