A clinical investigation of the tooth whitening efficacy of a new hydrogen peroxide-containing dentifrice

OBJECTIVE: The objective of this four-week, double-blind clinical study was to assess the tooth whitening efficacy of a new dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride, and sodium tripolyphosphate in a high-cleaning silica base (Test Dentifrice), relative to that of a control dentifrice containing 0.243% sodium fluoride in a silica base (Control Dentifrice). METHODOLOGY: Following a baseline oral soft tissue examination and tooth shade assessment using the Vita Shade Guide, qualifying adult male and female subjects from the New Delhi, India area were randomized into either the Test or Control Dentifrice group. The two groups were balanced for baseline mean Vita Shade Guide rank scores. All subjects were provided with their assigned dentifrice and a soft-bristled adult toothbrush for home use. Subjects were instructed to brush their teeth for two minutes twice daily (morning and evening), using only the dentifrice provided, and to refrain from using any other oral hygiene products for the entire four weeks of the study. There were no restrictions regarding diet or smoking habits during the course of the study. Oral soft tissue and tooth shade evaluations for each subject were repeated after two and four weeks of product use. RESULTS: Forty-four (44) subjects complied with the protocol and completed the entire study. At the two- and four-week examinations, the Test Dentifrice group had statistically significant mean shade rank score reductions of 4.04 and 5.17, respectively, compared to baseline (p < 0.05), while the Control Dentifrice had respective reductions of 0.41 and 0.53, which were also statistically significant. The mean shade rank reductions in the Test group compared to those in the Control group at two and four weeks were 3.63 and 4.64, respectively, and were statistically significant (p < 0.05). CONCLUSION: A new whitening dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride and sodium tripolyphosphate has significant tooth whitening effectiveness, producing a mean shade rank score reduction from baseline of 5.17 after four weeks' use.     

Correlates of affective empathy,perspective taking,and generativity among a sample of adults

Previous research suggests that empathy can be cultivated by social ideals and relationships with people. The current study examines family importance and religious importance as correlates of affective empathy, perspective taking, and generativity among a sample of adults aged 18 to 35 (N = 722). Given the ethnic and racial diversity represented by Millennials and Generation Z, the moderating role of racial group membership is explored as well. Results indicate that family importance is positively associated with affective empathy, perspective taking, and generativity for the overall sample, though the relationship is particularly strong for non-Hispanic whites. Religious importance is significantly related to affective empathy and generativity (not perspective taking), primarily among Black, Indigenous, and/or People of Color. Due to the increasing visibility of victimization towards socially vulnerable groups, it is important to understand how attitudes oriented towards helping and empathizing with others are fostered. Implications for further research are discussed.     

High lenticular tolerance to ultraviolet radiation‐B by pigmented guinea‐pig; application of a safety limit strategy for UVR‐induced cataract

Purpose: The purpose of this study was to determine a threshold measure, maximum tolerable dose (MTD), for avoidance of UVR‐B‐induced cataract in the pigmented guinea‐pig. Methods: Thirty pupil‐dilated anesthetized young female guinea‐pigs, divided into five equal groups, received between 0 and 84.9 kJ/m² unilateral UVR‐B. Lens extraction and in vitro lens photography occurred 24 hr after exposure. Measurement of intensity of lens light scattering served as quantifying tool for the degree of cataract. Data analysis included regression, using a second order polynomial model. The applied MTD concept was based on the UVR‐B dose–response curve obtained for the pigmented guinea‐pig. A smaller number of pigmented guinea‐pigs, pigmented rats and albino rats underwent morphometric analysis of the anterior segment geometry. Results: All eyes exposed to UVR‐B developed cataract in the anterior subcapsular region. MTD for avoidance of UVR‐B‐induced cataract was 69.0 kJ/m² in the pigmented guinea‐pig. Iris was considerably thicker in the guinea‐pig than in the rats. Lens blockage by the dilated iris was lowest in the guinea‐pig. Conclusions: Maximum tolerable dose for avoidance of UVR‐B‐induced cataract in the pigmented guinea‐pig was 69.0 kJ/m², over 10‐fold higher than the threshold 5 kJ/m² obtained by Pitts et al. in the pigmented rabbit. Maximum tolerable dose is an appropriate method for estimation of toxicity for UVR‐B‐induced cataract in the guinea‐pig. The pigmented guinea‐pig is significantly less sensitive to UVR‐B exposure than the pigmented rabbit and pigmented rat.     

Effect of statins on the development of renal dysfunction

Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) decrease serum cholesterol. Dyslipidemia is believed to be associated with the development of renal dysfunction. It was postulated that statins may reduce the development of renal dysfunction. The effect of statin use on the development of renal dysfunction in 197,551 patients (Department of Veterans Affairs, Veterans Integrated Service Network 16 [VISN16] database) was examined. Of these patients, 29.5% (58,332 patients) were statin users and 70.5% (139,219 patients) were not. Development of renal dysfunction was defined as doubling of baseline creatinine or increase in serum creatinine > or =0.5 mg/dl from the first to last measurement with a minimum of 90 days in between. During 3.1 years of follow-up, 3.4% of patients developed renal dysfunction. After adjustment for demographics, diabetes mellitus, smoking, hypertension, and other medications (mainly angiotensin-converting enzyme inhibitors, calcium channel blockers, and aspirin), use of statins decreased the odds of developing renal dysfunction by 13% (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.82 to 0.92, p <0.0001). The beneficial effect of statins appeared to be independent of the decrease in cholesterol. Other variables that affected the development of renal dysfunction were age (OR 1.04, 95% CI 1.03 to 1.04, p <0.0001), diabetes (OR 1.77, 95% CI 1.68 to 1.86, p <0.0001), hypertension (OR 1.11, 95% CI 1.02 to 1.2, p = 0.0153), and smoking (OR 1.12, 95% CI 1.02 to 1.24, p = 0.0244). In conclusion, statin use may retard the development of renal dysfunction. The beneficial effect of statins in preventing the development of renal dysfunction appears to be independent of their lipid-lowering effect.