Effect on adhesion of a nanocapsules-loaded adhesive system

Abstract This study aimed to evaluate the in situ degree of conversion, contact angle, and immediate and long-term bond strengths of a commercial primer and an experimental adhesive containing indomethacin- and triclosan-loaded nanocapsules (NCs). The indomethacin- and triclosan-loaded NCs, which promote anti-inflammatory and antibacterial effects through controlled release, were incorporated into the primer at a concentration of 2% and in the adhesive at concentrations of 1, 2, 5, and 10%. The in situ degree of conversion (DC, n=3) was evaluated by micro-Raman spectroscopy. The contact angle of the primer and adhesive on the dentin surface (n = 3) was determined by an optical tensiometer. For the microtensile bond strength µTBS test (12 teeth per group), stick-shaped specimens were tested under tensile stress immediately after preparation and after storage in water for 1 year. The data were analyzed using two-way ANOVA, three-way ANOVA and Tukey's post hoc tests with α=0.05. The use of the NC-loaded adhesive resulted in a higher in situ degree of conversion. The DC values varied from 75.07 ± 8.83% to 96.18 ± 0.87%. The use of NCs in only the adhesive up to a concentration of 5% had no influence on the bond strength. The contact angle of the primer remained the same with and without NCs. The use of both the primer and adhesive with NCs (for all concentrations) resulted in a higher contact angle of the adhesive. The longitudinal μTBS was inversely proportional to the concentration of NCs in the adhesive system, exhibiting decreasing values for the groups with primer containing NCs and adhesives with increasing concentrations of NCs. Adhesives containing up to 5% of nanocapsules and primer with no NCs maintained the in situ degree of conversion, contact angle, and immediate and long-term bond strengths. Therefore, the NC-loaded adhesive can be an alternative method for combining the bond performance and therapeutic effects. The use of an adhesive with up to 5% nanocapsules containing indomethacin and triclosan and a primer with no nanocapsules maintained the long-term bond performance.

Solubilization of certain Analgesics by cetomacrogol 1000

Solubilization of certain nonsteroidal anti-inflammatory drugs, viz., phenacetin, ibuprofen and indomethacin by Cetomacrogol 1000 [Cetomacrogol] has been investigated. The values of the ratio of mole drug solubilized per mole micellar Cetomacrogol revealed that the solubilizing power of Cetomacrogol towards ibuprofen is higher than that for phenacetin or indomethacin. One Cetomacrogol micelle solubilizes 38, 17 and 6 molecules of ibuprofen, phenacetin and indomethacin, respectively. Spectrophotometry as well as solubility measurements in different solvents have been used to provide evidence on the environment of the solubilizate molecule in the micelle. On the basis of the results obtained, it was concluded that these drugs are solubilized as follows: Phenacetin and ibuprofen are solubilized in the hydrocarbon core and in the polyoxyethylene region adjacent to the hydrocarbon core. Indomethacin is wholly solubilized in the polyoxyethylene layer adjacent to the hydrocarbon core. The ability of the surfactants to accelerate the dissolution rate of the drug was also investigated. The dissolution profiles of these drugs in Cetomacrogol revealed marked enhancement of dissolution and there is a good correlation between the dissolution efficiency of the three drugs and their solubility in Cetomacrogol at the same temperature