Adsorption, Adhesion, and Wettability of Commercially Available Cleansers at Dental Polymer (PMMA) Surfaces

This study aims to evaluate the adsorptive, adhesive, and wetting energetic properties of five commercially available cleansers in contact with model dental polymer (PMMA). It was assumed that the selected parameters allow for determining the optimal concentration and place of key component accumulation for antibacterial activity in the bulk liquid phase and prevention of oral plaque formation at the prosthetic material surface. The adsorptive (Gibbs' excesses <i>Γ_LV</i>, critical micellar concentration) and thermal (entropy and enthalpy) surface characteristics originated from surface tension <i>γ_LV(T)</i> and <i>γ_LV(C)</i> dependences. The surface wetting properties were quantified upon the contact angle hysteresis formalism on the advancing <i>Θ_A</i>, receding <i>Θ_R</i> contact angles, and <i>γ_LV</i> as the input data, which yield a set of wettability parameters: 2D adsorptive film pressure, surface free energy with its dispersive and polar components, work of adhesion, and adhesional tension, considered as interfacial interaction indicators. In particular, molecular partitioning <i>K_p</i> and <i>Γ_LV</i> are indicators of the efficiency of particular active substance accumulation in the volume phase, while <i>γ_SV</i>, <i>a = Γ_SL</i>/<i>Γ_LV</i>, and <i>W_A</i> point to the degree of its accumulation at the immersed polymer surface. Finally, the liquid penetration coefficient <i>PC</i> and the Marangoni temperature gradient-driven liquid flow speed were estimated.