Hydrogen peroxide release kinetics into saliva from different whitening products: a double-blind, randomized clinical trial

The objective of this study is to compare salivary hydrogen peroxide (HP) release kinetics and potential toxicity of systemic exposure of four different whitening products. A double-blind, randomized controlled trial was conducted in a Portuguese dental faculty clinic. Two hundred forty volunteers were randomized to eight intervention groups. Participants were randomly assigned to receive active or placebo applications of one of four different products: Opalescence 10% PF™ (OPL), Vivastyle? 10%™ (VS10%), Vivadent Paint On Plus™ (PO+), and Trés White Supreme™ (TWS). Saliva collection was obtained by established methods at different times. The HP salivary content was determined by a photometric method. Salivary HP variations, total amount of salivary HP, and counts of subjects above the safe daily HP dose were the main outcome measures. All whitening systems significantly released HP to the saliva when compared to placebo, and all showed different release kinetics. The adaptable tray system (TWS) presented a risk increase of 37% [20–54%, 95% confidence interval] when compared to the other systems. The use of an adaptable tray whitening system with higher concentration of HP increases the toxicity potential.     

Abordaje combinado para la nefrectomía parcial en lesiones renales complejas

ObjectiveTo develop a combined surgical approach (laparoscopic and open) that allows an increased vascular control and decreased ischemia time, maintaining the advantages of pure laparoscopic partial nephrectomy (LPN).Material and methodsDuring the laparoscopic phase, dissection of the kidney and its pedicle is achieved. Then, an open approach is initiated through a mini-laparotomy, with the kidney being brought to the incision, improving the identification and exposition of the tumors. Following tumor identification by ultrasound, exeresis of the lesion is performed with or without vascular clamping.ResultsThrough this approach we performed the excision of complex lesions in 6 patients. Mean surgical time was 192 minutes (range 180-210) and mean warm ischemia time was 13 minutes (0-22), with a mean blood loss of 267 mL (100-500). Average pre and postoperative glomerular filtration rate was 51.5 (28-90) and 48.8 mL/min/1.73 m² (19-90), respectively. In one patient, suture repair of the pelvicaliceal system was needed, with no other perioperative morbidities being reported.ConclusionsThis combined approach is a minimally invasive surgical alternative, reproducible and safe which preserves the virtues of pure LPN. It allows a better control of the vascular pedicle, reducing the risk of hemorrhage and the warm ischemia time. This technique may be either considered in the treatment of renal masses with indication for partial nephrectomy but of complex laparoscopic approach or as a surgical approach in the early learning curve of the LPN.     

Representation of pregnant smokers on cigarette use: a study carried out at a hospital in the interior of the state of São Paulo

This study sheds light on the smoking pregnant women's outlook on cigarette use. The Theory of Social Representations was used as a theoretical reference. For data analysis, the Collective Subject Discourse was constructed. Of the 27 women that were interviewed, 18 had finished elementary education, 8 had completed secondary education, and one had college level education; 14 had a stable union and 6 were married. Four themes emerged from the interviews: (1) starting to smoke: a natural, social practice; (2) satisfaction versus guilt; (3) shattering news: effects of smoking on pregnancy; and (4) quitting: between will and ability. Pregnant women revealed negative ideas about smoking, considering smoking the worst of addictions and a potential cause for complications to the fetus and the mother. Smoking was represented in a prejudicial manner, disregarding the existence of treatment and the need for it. Emerging difficulties were related to quitting, for which professionals, information and adequate approaches for treatment and support for achieving success are utmost necessities.     

Exploring Penicillin G as an Intrawound Antibiotic Powder for Prevention of Postoperative Shoulder Infections: Does It Exhibit In Vitro Chondrotoxicity?

Cutibacterium acnes (C. acnes) is a significant insidious pathogen for postoperative infections in shoulder surgery. Studies have demonstrated that certain topical antibiotic powders used have the potential for chondrotoxicity. Benzylpenicillin, commonly referred to as Penicillin G (Pen G) has the lowest minimum inhibitory concentration (MIC) for C. acnes. There is no research regarding the topical application of Pen G during shoulder surgery, nor has its chondrocyte toxicity been previously investigated. This study sought to characterize the in vitro chondrocyte toxicity of Pen G. Culture-derived bovine chondrocytes were exposed to serial Pen G concentrations and compared with a positive and negative control. A negative control of growth medium and positive control of 1% Triton solution. The chondrocyte viability was assessed via spectrophotometer absorbance. The treatment groups were analyzed using one-way repeated measures analysis of variance and Pearson's correlation analysis. The chondrocyte viability was significantly higher for all Pen G concentrations as compared with the positive control (p < 0.001). All concentrations of Pen G exhibited continued chondrocyte metabolic activity over time. Analysis of variance, independent of time, demonstrated no significant decrease in chondrocyte viability for Pen G concentrations ≤6.25 mg/ml, as compared with the negative control (p > 0.05). Pen G demonstrated a significant negative correlation with its concentration and absorbance (r = 0.371, p < 0.001), however, concentrations ≤6.25 mg/ml did not demonstrate a significant decrease in chondrocyte viability (p = 0.063). Pen G in concentrations appropriate for C. acnes is not significantly chondrotoxic and may be safe for intrawound application. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:726-730, 2020