In Vitro Effect of Acidic Solutions and Sodium Fluoride on Surface Roughness of Two Types of CAD-CAM Dental Ceramics

Abstract

Objectives. This study assessed the effect of immersion in acidic solutions and sodium fluoride on surface roughness of dental ceramics. Materials and Methods. 40 blocks of Vitablocs Mark II and IPS e.max CAD (5 × 5 × 3) were prepared. The samples were divided into five groups (n = 8) for immersion in artificial saliva (control), artificially prepared gastric acid, acetic acid, 0.02% sodium fluoride + gastric acid, and 0.02% sodium fluoride + acetic acid. The samples were immersed for 168 hours in the respective solutions except for sodium fluoride, in which the samples were immersed for 69 hours. The surface roughness of samples was measured before and after immersion using a profilometer. The surface roughness changes of three specimens of each group were evaluated by scanning electron microscopy (SEM). Data were analyzed using one-way and two-way ANOVA, Tukey’s test, and independent t-test. Results. Significant changes were noted in Ra ( P = 0.002 ) and Rq ( P < 0.0001 ) in both types of ceramics. The lowest changes in Ra and Rq parameters were seen in artificial saliva and gastric acid and highest changes occurred following immersion in 0.02% sodium fluoride + acetic acid and 0.02% sodium fluoride + gastric acid, respectively. Changes in Rz were also significant following immersion in Vitablocs Mark II ( P < 0.05 ). Immersion in 0.02% sodium fluoride + gastric acid and 0.02% sodium fluoride + acetic acid produced a rougher surface on both types of ceramics (SEM). Conclusion. Exposure of Vitablocs Mark II CAD and IPS e.max CAD to 0.02% sodium fluoride + gastric acid and 0.02% sodium fluoride + acetic acid significantly increased their surface roughness, while for Vitablocs Mark II, lager defects were seen on its surface.

Vickers micro-hardness study of the effect of fluoride mouthwash on two types of CAD/CAM ceramic materials erosion

“…According to our result, surface microhardness values of Vitablocs Mark II and IPS e.max CAD were negatively affected by the exposure to an acidic environment and sodium fluoride mouth wash. Regarding the results of the present study and those reported by the previous study [ 14 ], preventive measures involving the fluoride should be used in patients with bulimia or GERD more cautiously.…”

“…According to a previous study [ 14 ], exposure to acidic solutions and sodium fluoride mouth wash significantly increased the surface roughness parameters of Vitablocs Mark II and IPS e.max CAD compared to immersion in saliva. These findings were also confirmed by SEM evaluations.…”

“…G S (saliva group/negative control): In this group, the samples were immersed in artificial saliva and incubated at 37 °C for 168 h. The used artificial saliva was prepared by 1 M sodium chloride (NaCl), 0.2 M monosodium phosphate (NaH 2 PO 4 ), 1 M acetic acid, 0.2 M calcium chloride (CaCl 2 ), and 2.0% sodium azide (NaN 3 ) at pH = 6.3 [ 14 ].…”

“…Organic acids such as acetic acid and citric acid may have fairly corrosive potential due to their chelating effect on ceramics [ 13 ]. In a previous study conducted by Farhadi et al [ 14 ] it was reported that the surface roughness of two types of CAD/CAM ceramics increased after exposure to acidic environment followed by immersion in sodium fluoride solution. Kukiattrakoon et al [ 15 ] have concluded that acidic agents used in their study decreased the surface roughness of four types of tested ceramics.…”

“…Kukiattrakoon et al [ 15 ] have concluded that acidic agents used in their study decreased the surface roughness of four types of tested ceramics. On the other hand, the behavior of ceramic in contact with gastric acid in studies is inconsistent with different exposure times and study design [ 14 , 16 ].…”