Assessment of sensitivity of selected Candida strains on antimicrobial photodynamic therapy using diode laser 635 nm and toluidine blue - In vitro research.

BACKGROUND: Photodynamic therapy is believed to be a promising treatment for Candida infections. This study evaluated the efficacy of antimicrobial photodynamic therapy (aPDT) using the 635 nm diode laser light and toluidine blue (TB) in the elimination of selected Candida species cultured on acrylic surface. METHODS: 108 acrylic plates (Methyl Methacrylate Polymer, routinely used for the production of prosthetic dentures) were placed in three sterile Petri dishes and poured with prepared suspensions of Candida strains: C. albicans, C. glabrata, and C. krusei. After all procedures of fungi incubation, fungal biofilm was visible on the plates' surfaces. The acrylic plates were divided into nine study groups (B) and nine control groups (K) for further experiments. In the study groups, the acrylic plates with fungal biofilm were immersed in TB and afterwards laser irradiation was applicated with different exposure parameters (groups: B1 - 400 mW, 24 J/cm2, 30 s; B2 - 300 mW, 18 J/cm2, 30 s; B3 - 200 mW, 12 J/cm2, 30 s) separately for each Candida species. The control groups contained following parameters: no exposure to laser light or TB, treatment only with TB without laser irradiation, or only laser irradiation without previous immersion in TB. Calculations of colony forming units (CFUs) were conducted by using aCOlyte (Synbiosis). Differences in CFUs were analyzed by the Wilcoxon test. RESULTS: In all study groups, the reduction in CFUs was statistically significant. The differences in CFUs before and after intervention were insignificant. The K3 C.a. control group showed a statistical reduction of Candida albicans after laser irradiation. CONCLUSION: Our study confirmed the efficacy of aPDT against C. albicans, C. glabrata and C. krusei being dependent on the laser parameters and the type of fungus. The advantage of this study is the validation of aPDT effectiveness in in vitro studies to transpose this data into future clinical trials using photodynamic therapy in the treatment of oral candidiasis.

Comparison of ropivacaine and lidocaine with epinephrine for infiltration anesthesia in dentistry. A randomized study.

PURPOSE: To compare the efficacy of maxillary infiltration anesthesia with 0.5% plain ropivacaine or 2% lidocaine with epinephrine 1:100,000. METHODS: 60 volunteers received 1.8 ml of the anesthetic for infiltration anesthesia of maxillary central and lateral incisors and canine teeth. The onset time and duration of pulp anesthesia were assessed with an electric pulp tester. The duration time of numbness of the upper lip was also monitored. Blood pressure and heart rate were measured before and after administration of the solution. RESULTS: The efficacy of anesthesia of the lateral and central incisors was 100% for both anesthetics. There were small insignificant differences in effectiveness of canine pulp anesthesia. The mean onset time was significantly shorter for ropivacaine--2.2 minutes vs. 5.1 for lidocaine. Ropivacaine also had a significantly longer duration of action--mean time 79.2 minutes. Ropivacaine caused statistically significant increases in blood pressure and heart rate.