The change of teeth color, whiteness variations and its psychosocial and self-perception effects when using low vs. high concentration bleaching gels: a one-year follow-up.

BACKGROUND: Dental bleaching in traditional concentrations generates greater sensitivity. In this respect, new systems of lower concentration of hydrogen peroxide for tooth bleaching appeared, with color stability unknown over time. The aim of this study was to compare the change and stability of color with low-concentration (6%) hydrogen peroxide gel in an in-office bleaching setting relative to conventional 37.5% gel, including their effects on psychosocial and esthetic self-perception, after 1 year. METHODS: Patients (n = 25) were assessed at 12 months post bleaching treatment (whitening with 6% chemo-activated alkaline formula gel versus 37.5% traditional concentration gel). Color changes were measured objectively using total variation in color (ΔE), and subjectively using Vita Classical and Vita Bleached scale (ΔSGU) by calibrated evaluators (Kappa = 0.85). The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and Oral Health Impact Profile (OHIP-14) aesthetic questionnaires were used to measure the self-perception and the psychosocial impact of the bleaching protocols. RESULTS: The effect (ΔE) of 37.5% HP (8.37 ± 2.73) was significantly better than that of 6% HP (5.27 ± 2.53) in terms of color rebound after 1 year of follow-up. There were significant differences in psychosocial impact and esthetic self-perception measurements prior to bleaching versus one-year post-whitening time points; positive effects were maintained. CONCLUSIONS: Low concentration (6%) achieved effective bleaching with good stability after 1 year, accompanied by a positive psychosocial impact and enhanced self-perception at follow-up. TRIAL REGISTRATION: NCT03217994 (before enrollment of the first participant). Data register: July 14, 2017.

Physical exercise improves plasmatic levels of IL-10, left ventricular end-diastolic pressure, and muscle lipid peroxidation in chronic heart failure rats.

Chronic heart failure (CHF) is characterized by left ventricular dysfunction, resulting in hemodynamic changes, sustained inflammatory state, as well as increase in oxidative stress. Physical exercise has been described as an important nonpharmacological procedure in the treatment of CHF, contributing to the improvement of the clinical outcomes in this disease. This study evaluated the effects of physical training on hemodynamics, muscle lipid peroxidation, and plasmatic levels of IL-10 in CHF rats. The left coronary artery was ligated to induce CHF, or sham operation was performed in control groups. Rats were assigned to one of four groups: trained CHF (T-CHF, n = 10), sedentary CHF (S-CHF, n = 10), trained sham (T-Sham, n = 10), or sedentary sham (S-Sham, n = 10). Trained animals had carried out a swimming protocol, 60 min/day, 5 days/wk, during 8 wk, whereas sedentary animals remained without training. Eight weeks of physical training promoted an improvement of diastolic function represented by a reduction of the left ventricular end-diastolic pressure in the T-CHF group compared with the S-CHF group (P < 0.05). Lipid peroxidation evaluated in gastrocnemius muscle using thiobarbituric acid reactive substance assay was higher in the S-CHF group compared with all other groups (P < 0.05). However, there were no differences between T-CHF compared with S-Sham and T-Sham groups. The plasmatic levels of IL-10 were lower in the S-CHF group compared with all other groups (P < 0.05). These findings demonstrate that regular physical training using a swimming protocol, with duration of 8 wk, improves the cardiac function and the anti-inflammatory response and reduces muscle cellular damage.

Preventive Use of a Resin-based Desensitizer Containing Glutaraldehyde on Tooth Sensitivity Caused by In-office Bleaching: A Randomized, Single-blind Clinical Trial.

OBJECTIVE: To evaluate the risk and intensity of bleaching-induced tooth sensitivity (TS) after in-office bleaching following topical application of a resin-based glutaraldehyde desensitizer. METHODS: Thirty-three patients were randomly assigned to the experimental (Gluma Desensitizer Liquid, Heraeus Kulzer, Hanau, Germany) and placebo groups. The placebo or Gluma Desensitizer Liquid was applied for one minute prior to application of an in-office bleaching gel. Bleaching was performed with 35% hydrogen peroxide gel (three applications × 15 minutes each) over two sessions, one week apart. The color of the anterior teeth was evaluated before and 21 days after treatment using the VITA Classical shade guide, Bleachedguide 3D, and Easyshade spectrophotometer. TS during and after the bleaching was recorded according to the visual analog (VAS) and numerical rating (NRS) scales. All data were submitted to statistical analysis (α=0.05). RESULTS: There was no significant difference in absolute risk or intensity of TS between the two groups (risk and VAS, p=0.93 and 0.31, respectively; NRS, p≥0.45). At the end of the bleaching protocol, tooth whitening was observed in both groups, as evident from color change in shade guide units (ΔSGU, 4.1-7.1; both guides) and overall color change (ΔE, 7.4-9.3 units); however, there were no significant differences in whitening between the two groups ( p>0.11). CONCLUSION: Gluma Desensitizer Liquid was not able to reduce the risk or intensity of TS. Bleaching efficacy was not affected by application of the desensitizer.

Comparison of Effectiveness and Sensitivity Using Two In-Office Bleaching Protocols for a 6% Hydrogen Peroxide Gel in a Randomized Clinical Trial.

OBJECTIVE: The aim of this blinded and randomized clinical trial was to compare two application protocols (one 36-minute application vs three 12-minute applications). We then assessed the effectiveness of the bleaching and any increase in sensitivity that was induced by bleaching via a split-mouth design. METHODS AND MATERIALS: Thirty patients were treated. One group had a half arch of teeth treated with a traditional application protocol (group A: 3 × 12 minutes for two sessions). The other received an abbreviated protocol (group B: 1 × 36 minutes over two sessions). Two sessions were appointed with a two-day interval between them. The tooth color was registered at each session, as well as one week and one month after completing the treatment via a spectrophotometer. This measured L*, a*, and b*. This was also evaluated subjectively using the VITA classical A1-D4 guide and VITA Bleachedguide 3D-MASTER. Tooth sensitivity was registered according to the visual analogue scale (VAS) scale. Tooth color variation and sensitivity were compared between groups. RESULTS: Both treatments changed tooth color vs baseline. The ΔE* = 5.71 ± 2.62 in group A, and ΔE* = 4.93 ± 2.09 in group B one month after completing the bleaching (p=0.20). No statistical differences were seen via subjective evaluations. There were no differences in tooth sensitivity between the groups. The absolute risk of sensitivity reported for both groups was 6.25% (p=0.298). The intensity by VAS was mild (p=1.00). CONCLUSIONS: We used hydrogen peroxide (6%) that was light activated with a hybrid LED/laser and two different protocols (one 36-minute application vs three 12-minute applications each for two sessions). These approaches were equally effective. There were no differences in absolute risk of sensitivity; both groups reported mild sensitivity.