Fluoridated Versus Non-Fluoridated Products: Effects on Ceramic Surface Deterioration

Objectives: The aim of this study was to evaluate the impact of fluoridated and non-fluoridated toothpastes and mouthrinses on the color stability and surface roughness of ceramic materials.
Methods: Thirty lithium disilicate (LD) and 30 zirconia (Zr) samples (10x10x1 mm) were used. Samples were equally divided into five experimental groups: fluoridated, chlorhexidine 0.12%, and non-fluoridated mouthrinses; and fluoridated and non-fluoridated toothpastes. A toothbrushing simulator was used with a slurry (ratio 1:2 toothpaste and deionized water) for 20,000 strokes (2 years use) performed with vertical/horizontal/zig-zag movements and 350 g weight with a soft toothbrush. Optical properties and surface roughness were evaluated before and after simulation. Surface roughness (Ra) was evaluated using profilometry and color stability (ΔE₀₀) was calculated using spectrophotometry. Data is presented as mean±SD. Kruskal-Wallis followed by Dunn’s test were used for comparison among the experimental groups.
Results: For LD, ΔE₀₀ varied from 0.21±0.09 for the fluoridated mouthrinse group to 0.45±0.14 for the non-fluoridated toothpaste group. Statistically significant differences were found between fluoridated and non-fluoridated toothpastes (p=0.004) and between non-fluoridated toothpaste and chlorhexidine mouthrinse (p=0.011). For Zr, ΔE₀₀ varied between 0.17±0.02 for the fluoridated toothpaste group to 0.33±0.27 for the non-fluoridated mouthrinse group. Statistically significant differences were found between fluoridated and non-fluoridated toothpastes (p=0.014). For LD, surface roughness increased in mouthrinse groups (ΔRa=0.06±0.39, 0.29±0.45, and 0.16±0.62) and decreased in toothpaste groups (ΔRa=-0.20±0.60, -0.41±0.69). For Zr, surface roughness increased in all groups except for chlorhexidine mouthrinse (ΔRa=0.33±0.33, -0.25±0.43, 0.25±0.33, 0.02±0.54, 0.25±1.09). No statistically significant differences were found among the groups for LD or Zr (p=0.22, 0.17, respectively).
Conclusions: Whereas statistically significant differences in color stability were observed, they may not be clinically perceptible (ΔE₀₀ <0.8). No statistical differences in surface roughness were observed. It seems fluoride did not have an impact on surface deterioration of ceramics according to the present aging protocol.