• CAMBRA and its effect on surface roughness of various restorative materials

      Bolding, Lauren Mills; Masri, Radi, 1975-; Driscoll, Carl F. (2012)
      Purpose: The purpose of this study was to investigate the effect of various anti-caries agents on the surface roughness of three different restorative materials. Materials and Methods: Sixty-four specimens of each material (porcelain, base metal and titanium alloy) were prepared and separated into four groups for soaking in anti-caries agents (Prevident, ACT, chlorhexidine and water). A profilometer was used to measure surface roughness before and after soaking for two years simulated usage. The change in surface roughness for each specimen was calculated. Statistical analysis was completed using a factorial analysis of variance (two-way ANOVA) followed by Tukey's HSD test. A p value ≤0.05 was considered significant. Results: The results demonstrate that there was no significant difference in mean change in surface roughness between the three materials, porcelain, base metal, and titanium. The results further demonstrate that there was a significant difference in mean change in surface roughness between Prevident Dental Rinse and chlorhexidine gluconate. There was no significant difference between water, ACT, and chlorhexidine gluconate. There was also no significant difference between Prevident Dental Rinse, water, and ACT. There was a significant interaction between Prevident Dental Rinse and chlorhexidine within the porcelain samples. Prevident Dental Rinse produced a negative change in surface roughness while chlorhexidine gluconate produced a positive change in surface roughness. Conclusion: Within the limitations of this study, it can be concluded that Prevident Dental Rinse and chlorhexidine gluconate may cause a change in surface roughness of porcelain when used for a period of two years. Prevident Dental Rinse may cause an increase in surface roughness of porcelain while chlorhexidine gluconate may cause a decrease in surface roughness of porcelain.
    • The Effect of CAMBRA Agents on Fracture Strength of Lithium Disilicate Crowns

      Sinada, Naif Ghazi; Masri, Radi, 1975- (2017)
      The Caries Management By Risk Assessment (CAMBRA) protocol outlines an approach in which certain agents can be used to serve as protective factors toward the management of dental caries. In this study, the effects of particular CAMBRA agents on the fracture strength of lithium disilicate ceramics (commonly used in dentistry) are studied. While Chlorhexidine exhibited no effects on the fracture strength of these ceramics, Prevident showed a decrease in the fracture strength of all the ceramics studied. These results indicate that clinicians should proceed with caution when using these CAMBRA agents in patients restored with lithium disilicate ceramics. Further studies on the particular mechanisms whereby this reduction in fracture strength occurs are indicated.
    • The Effect of CAMBRA Recommended Anti-Caries Agents on Surface Roughness of Lithium Disilicate Ceramics

      Ghunaim, Dima Hanna; Masri, Radi, 1975-; Driscoll, Carl F. (2014)
      Purpose: The purpose of this study was to explore the clinical importance of the effect of Prevident and chlorhexidine on the surface roughness of three commonly utilized lithium disilicate ceramics: pressed (Press), milled (CAD), milled and veneered with fluorapatite (CAD/CERAM). Methods and Materials: Seventy-six rectangular specimens in each group of Press, CAD, and CAD/CERAM were fabricated. A profilometer was used to measure the surface roughness prior to and after soaking. The samples were immersed in the assigned anti-caries solution in an airtight plastic container. For the simulation of 2 years use the samples were soaked in chlorhexidine for 3 hours, Prevident, 6% alcohol and distilled water for 12 hours. Statistical analysis was completed using a two-way ANOVA followed by Tukey's HSD test. A p value ≤.05 was considered significant. Results: The results demonstrated that Press samples became significantly rougher. In addition to that, the surface roughness of CAD and CAD/CERAM was significantly decreased. However, CAD was significantly less rough than CAD/CERAM. Water did not significantly change the surface roughness of ceramics, while 6% alcohol, Prevident, and chlorhexidine significantly decreased the roughness of the ceramics. There was no significant difference in the increase of surface smoothness among the three solutions. A significant interaction was found only with water, the control. Conclusion: Within the limitations of this study, it can be concluded that Prevident and chlorhexidine can change the surface roughness of lithium disilicate ceramics when used for a period of 2 years. The surface roughness of Press increased, while that of CAD and CAD/CERAM decreased.