Laser Influence on Dental Sensitivity Compared to Other Light Sources Used During In-office Dental Bleaching: Systematic Review and Meta-analysis

Low and high hydrogen peroxide concentrations of in-office dental bleaching associated with violet light: an in vitro study

OBJECTIVES

This study aims to assess hydrogen peroxide (HP) penetration within the pulp chamber, color change (CC), physical-chemical properties, and temperature using in-office different concentration bleaching gels with or without violet light.

MATERIALS AND METHODS

Fifty teeth were divided into five groups (n = 10) based on the HP concentration bleaching gels used (6% and 35%) and the used violet light (with or without). HP penetration within the pulp chamber was measured using UV-Vis. The CC was evaluated with a digital spectrophotometer. Initial and final concentration, and pH were measured through titration, and a Digital pHmeter, respectively. Temperature analyses were measured through a thermocouple. Statistical analysis included two-way ANOVA, Tukey's, and Dunnett's test (α = 0.05).

RESULTS

The presence of violet light did not affect the amount of HP within the pulp chamber, or the CC (p > 0.05). Greater penetration of HP was observed within the pulp chamber, as well as CC when using 35% HP (p < 0.05). The final concentration of both gels was lower than the initial concentration, regardless of the use of violet light (p < 0.05). The initial and final pH levels remained neutral and stable (p > 0.05). The pulp temperature increased when the gels were used in conjunction with violet light (p < 0.05).

CONCLUSIONS

Using violet light in conjunction with 6% or 35% HP does not alter the physical properties of the bleaching agents, the penetration of HP or enhance color change. However, an increase in temperature was observed when violet light was applied associated with bleaching gels.

CLINICAL RELEVANCE

While the simultaneous use of violet light with hydrogen peroxide 6% or 35% does not alter the material's properties, it also does not bring benefits in reducing hydrogen peroxide penetration and improving color change. Furthermore, the use of violet light increases pulp temperature.

Comparison of in-office and at-home bleaching techniques: An umbrella review of efficacy and post-operative sensitivity

Objectives

The objective of this umbrella review is to evaluate the efficacy and adverse effects of different teeth whitening techniques in-office (IO) and at-home (AH), regarding chromatic changes and teeth sensitivity.

Materials and methods

The search was carried out from several databases. The included studies were all systematic reviews with or without meta-analysis of RCT or quasi-RCT. The participants were patients that underwent external dental bleaching in permanent vital teeth. The interventions were in-office (IO) bleaching techniques and at-home (AT) bleaching techniques with different bleaching agents and concentrations.

Results

The search resulted in a total of 257 articles, and 28 SR were included in the qualitative analysis and nine in the quantitative analysis. There is no difference between in-office and at-home techniques in terms of color change (p = 0.95) and post-treatment sensitivity (p = 0.85). There is similarity risk and intensity of teeth sensitivity between AH and IO bleaching. IO bleaching with light-activated systems with low concentrations of bleaching agent showed similar results to IO bleaching techniques with high concentrated bleaching gels. With the application of the criteria of the AMSTAR 2 tool, the reviews were considered critically low to high.

Conclusions

There are no significant differences in terms of color change between the different bleaching techniques compared. Teeth sensitivity is always present regardless of the technique used. The use of light activation systems did not increase the intensity and risk of post-operative sensitivity.

Evidence-based fact checking for selective procedures in restorative dentistry

OBJECTIVES

Similar to other dental specialties, there are many clinical procedures in restorative dentistry that may or may not be supported by good evidence. Thus, the effectiveness of these procedures is uncertain. The aim of this paper is to reduce this knowledge gap by critically inspecting selective procedures in restorative dentistry and exploring if these well-established or widely advocated treatment modalities are necessary for improving treatment outcomes based on the best available evidence.

MATERIALS AND METHODS

A MEDLINE search was conducted to identify research on selective procedures while focusing on clinical trials and systematic reviews. Due to their practical relevance in the decision-making process, cost-effectiveness analyses were also included.

RESULTS

Mixed results were identified regarding the included interventions. Some procedures had adequate evidence supporting them while others were mostly based on beliefs.

CONCLUSIONS

A critical review of the available literature indicates that some common restorative procedures lack adequate support from high-quality research evidence.

CLINICAL RELEVANCE

This paper attempts to highlight the need to critically examine the scientific validity of traditional knowledge and techniques through the context of current research evidence. This will not only help generate consensus between educators, clinicians, and researchers regarding restorative procedures but will also lead to improved patient care and outcomes.

Titanium dioxide nanotubes in a hydrogen peroxide-based bleaching agent: physicochemical properties and effectiveness of dental bleaching under the influence of a poliwave led light activation

OBJECTIVES

The effects of different concentrations of titanium dioxide (TiO₂) into 40% hydrogen peroxide (HP) were evaluated as regards the effectiveness of dental color change either associated with activation by polywave LED light or not.

MATERIALS AND METHODS

TiO₂ (0, 1, 5, or 10%) was incorporated into HP to be applied during in-office bleaching (3 sessions/40 min each). Polywave LED light (Valo Corded/Ultradent) was applied or not in activation cycles of 15 s (total time of 2 min). The color of 80 third molars separated into groups according to TiO₂ concentration and light activation (n = 10) was evaluated at baseline and at time intervals after the 1st, 2nd, and 3rd bleaching sessions.

RESULTS

WI_D value was significantly higher when using HP with 5% TiO₂ in the 2nd session than the values in the other groups (p < 0.05). After the 2nd and 3rd sessions, the ΔEab value was significantly higher when activated with light (p < 0.05) for all agents containing TiO₂ or not. Zeta potential and pH of the agents were not modified by incorporating TiO₂ at the different concentrations.

CONCLUSIONS

The 5% TiO₂ in the bleaching agent could enhance tooth bleaching, even without light application. Association with polywave LED light potentiated the color change, irrespective of the presence of TiO₂ in the bleaching gel.

CLINICAL SIGNIFICANCE

HP with 5% TiO₂ could lead to a greater tooth bleaching response in the 2nd clinical session, as well as the polywave light can enhance color change.

Clinical comparison of diode laser- and LED-activated tooth bleaching: 9-month follow-up

This study aims to evaluate the effect of diode laser- or LED-activated tooth bleaching on color change, tooth sensitivity(TS), temperature variation, and gingival irritation (GI) for 9 months. Thirty-five subjects having anterior teeth with a color of A2 or darker were enrolled in the study. In a split-mouth design, one side of each arch was activated by a diode laser (Epic X, Biolase), and the other side was activated by an LED (Radii Plus, SDI) in conjunction with a bleaching agent (35%, Whiteness HP). The color change was evaluated by subjective (VitaClassic/Vita3D Master Bleachguide) and objective (spectrophotometer, Vita Easyshade) methods for up to 9 months. TS and GI were assessed by visual analogue scale (VAS) and gingival index, respectively, at the same recall periods. During the bleaching, the temperature variation was also recorded using a thermocouple. Statistical analyses were performed (p < 0.05). In the color evaluation, no statistically significant difference was found between diode laser and LED (p > 0.05), except for the 6-month spectrophotometric assessment (ΔE₀₀, ΔE_ab), where higher values were obtained with the laser (p < 0.05). The temperature difference and maximum temperature with diode were found to be significantly higher than LED (p < 0.05). Higher values were obtained with LED when the mean temperatures were compared (p < 0.05). There was no difference between the two activation methods in terms of TS and GI at any of the recalls (p > 0.05). The bleaching activated either with diode laser or LED performed similar clinical performance in terms of effective color change, tooth sensitivity, and gingival irritation with minimum temperature variations.