Biological action of bleaching agents on tooth structure: A review.

The use of bleaching agents to remove stains is one of the main dental procedures to improve the aesthetics of teeth. This review presents the main agents used for tooth whitening, existing clinical protocols, and the structural changes that may occur through their use. The main bleaching agents consist of hydrogen peroxide and carbamide peroxide, which are used in bleaching techniques for vital teeth.

The effect of photobiomodulation therapy associated with casein phosphopeptide-amorphous calcium phosphate fluoride paste on the treatment of posthome whitening tooth sensitivity and color change: A randomized clinical trial.

Objective: This study assessed whether combining photobiomodulation therapy (PBMT) with casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) paste can effectively reduce post-home whitening tooth sensitivity (TS) without compromising shade change.

Methods: Fifty participants were selected and assigned to one of four groups: (1) PLACEBO group-received a placebo paste and PBMT simulation; (2) PBMT group-received a placebo paste + PBMT; (3) CPP-ACPF group-received CPP-ACPF paste and PBMT simulation; (4) CPP-ACPF + PBMT group-received both CPP-ACPF paste and PBMT. The participants used whitening trays containing 22% carbamide peroxide for 2 h a day for 21 days.

Formulations of NaOCl-based in liquid, gel form or with surfactants on dentin deproteinization before fiber post cementation.

The objective of the study was to evaluate the effects of dentin deproteinization protocols for post space using different formulations containing sodium hypochlorite before fiber post cementation with self-adhesive resinous cement. The groups were divided according to the irrigation protocol (DWC, SHS, SHT and SHG). The residue cleanliness, bond strength, adhesive failure pattern, and tag formation at the adhesive interface between the self-adhesive cement and the dentin were evaluated.

Fracture resistance and bonding performance after antioxidants pre-treatment in non-vital and bleached teeth.

This study aimed to evaluate the effect of antioxidant solutions on fracture strength and bonding performance in non-vital and bleached (38% hydrogen peroxide) teeth. One hundred and eighty dentin specimens were obtained, 60 for each test: fracture strength, hybrid layer thickness, and bond strength. The groups (n=10) were randomly composed according to post-bleaching protocol: REST - restoration, without bleaching; BL - bleaching + restoration; SA - bleaching, 10% sodium ascorbate solution, and restoration; AT - bleaching, 10% α-tocopherol solution, and restoration; CRAN - bleaching, 5% cranberry solution, and restoration; CAP - bleaching, 0.

Anti-erosion effect of an experimental varnish on eroded dentin.

This in vitro study evaluated the effect of an experimental varnish containing 20% nano-hydroxyapatite (nHAP) associated with 5% stannous chloride (SnCl2) against erosive-abrasive wear on bovine dentin. Samples of bovine cervical dentin were pre-eroded (0.3% citric acid, pH 2.

A randomized clinical study of the performance of self-etching adhesives containing HEMA and 10-MDP on non-carious cervical lesions: A 2-year follow-up study.

Objective: To evaluate the association of HEMA and 10-MDP in the clinical performance of self-etching adhesives in the restoration of NCCLs during 2-years.

Materials And Methods: 60 restorations were performed in 17 volunteers and randomized into three groups: G1 (n = 20) - Prime and Bond Universal (10-MDP); G2 (n = 20) - Optibond All-in-One (HEMA); and G3 (n = 20) - Clearfil SE (10-MDP and HEMA). No cavity preparation was performed.

Influence of different glaze firing protocols on the mechanical properties of CAD-CAM ceramic materials.

Statement Of Problem: The influence of different glaze firing protocols and cooling on the behavior of computer-aided design and computer-aided manufacturing (CAD-CAM) ceramics is unclear.

Purpose: The purpose of this in vitro study was to investigate the influence of different glaze firing protocols on the abrasion resistance, surface roughness, microhardness, and brittleness index of CAD-CAM ceramics.

Material And Methods: Rectangular specimens of IPS e.

Bond strength and internal adaptation of customized glass fiber posts using different bulk-fill flow resins.

Background: This study aimed to evaluate the bond strength and internal adaptation of customized glass fiber posts using Bulk Fill flowable composite resins (BF) and conventional composite resin.

Material And Methods: Fifty bovine teeth were randomly divided (n=10) according to the following groups: G1 (control): glass fiber posts were adapted to the root canal and luted with Rely-X ARC cement (3M® ESPE); G2: fiber posts smaller than the root canal diameter were customized using Filtek™ Z350 XT (3M® ESPE) conventional composite resin, and luted similarly to Group 1. G3: posts were customized with Tetric N-Ceram Bulk Fill composite resin (Ivoclar Vivadent AG), G4: posts were customized with Filtek™ Bulk Fill Flow (3M® ESPE), and G5: posts were customized with SureFil SDRTM flow (DENTSPLY), respectively.

Anti-erosive profile of an experimental 5% SnCl₂ varnish containing different concentrations of NaF.

This in vitro study evaluated the anti-erosive effect of an experimental varnish containing 5% stannous chloride (SnCl₂) associated with different concentrations of NaF (NaF-free, 2.5% NaF, or 5.2% NaF) on bovine enamel and root dentin.

Antimicrobial activity of probiotics against oral pathogens around orthodontic mini-implants: an in vitro study.

Objective: The aim of this in vitro study was to evaluate the antimicrobial effect of five types of non-industrialized and industrialized probiotics on biofilms formed around orthodontic mini-implants. The null hypothesis tested was: there is no difference in the antimicrobial effect between the five types of probiotics tested around orthodontic mini-implants.

Methods: For the experiment, 120 mini-implants were immersed for seven days in Staphylococcus aureus solution for biofilm formation, and were subsequently plated in culture medium containing probiotics.

Effect of the several epoxy resin-based sealer compositions on adhesion interface in radicular dentin after calcium hydroxide intracanal medication removal.

Background: This study evaluated the effects of several epoxy resin-based sealer compositions (AHP, AH Plus; ADS, Adseal; SPL, Sealer Plus) on bond strength and intratubular dentin penetration of the endodontic obturation, in root canal previously treated with calcium hydroxide intracanal medication (CH) and removed by continuous ultrasonic irrigation (CUI).

Material And Methods: Forty-five maxillary canines were prepared up to F5 (ProTaper system), filled with CH, coronally sealed, and stored at 37ºC. After 1 week, CH was removed using 2.

Factors associated with depression, anxiety and stress among dentists during the COVID-19 pandemic.

The objective of this work was to evaluate the relationship between factors associated with the COVID-19 pandemic and depression, anxiety, and stress (DAS) in dentists. Factors associated with the COVID-19 pandemic were evaluated using a questionnaire and scores of the Depression, Anxiety, and Stress Scales-21 were measured. The differences between the DAS scores based on the factors associated with the COVID-19 pandemic were tested through the successive application of multivariate analysis of variance (MANOVA, α = 0.

Effect of post-space irrigation with acid solutions on bond strength and dentin penetrability using a self-adhesive cementation system.

Background: The aim of this study was to evaluate the effects of surface treatments with 1% peracetic acid (PA), solution containing 17% EDTA (SmearClear, Kerr Endodontics), solution containing a combination of 17% EDTA with 2% chlorhexidine (QMix, Dentsply Sirona) on the post-space root dentin compared to 2.5% sodium hypochlorite (NaOCl) on bond strength and resin tags length in dentin.

Material And Methods: Forty human-canine roots were endodontically treated and the post space was prepared.

Evaluation of various methods of methylene blue removal from the post space after photodynamic therapy on the bonding interface using different resin cementation systems.

Background: To evaluate the effects of three protocols for removing 0.01 % methylene blue from the post space after photodynamic therapy on bond strength and tag formation in the dentin of the fiber post space, using a conventional cementation system with an etch-and-rinse or universal adhesive system.

Methods: Sixty human canines were endodontically treated for fiber post cementation.

Impact of Finishing Protocols on Color Stability of CAD/CAM Ceramics: A Systematic Review.

Purpose: To analyze the current evidence on the impact of surface finishing protocols (such as manual polishing or glazing) on the color stability of in vitro simulated pigmentation of CAD/CAM ceramics.

Materials And Methods: Five electronic databases were searched on February 12, 2020. In vitro experimental studies were included based on the following strategy: intervention = surface treatment of CAD/CAM ceramics with glazing agents; comparison = surface treatment of CAD/CAM ceramics with manual polishing; and outcomes = color stability.

Effect of desensitizing agents on dentin hypersensitivity after non-surgical periodontal therapy: A systematic review and meta-analysis.

Objective: To investigate the effectiveness of desensitizing agents (DA) on dentin hypersensitivity (DH) after non-surgical periodontal treatment (NSPT) through a systematic review and meta-analysis.

Data: The PICO strategy was used to include randomized clinical trials in human subjects with DH (P) after NSPT treated with DA (I) compared to those treated with placebo or control (C) to identify DH relief (O). The Cochrane guidelines and GRADE was used to classify the risk of bias and the quality of the evidence, respectively.

Effect of nanohydroxyapatite associated with photobiomodulation in the control of dentin hypersensitivity: A randomized, double-blind, placebo-controlled clinical trial.

Purpose: To evaluate the effect of nanohydroxyapatite ( nHAP) associated with photobiomodulation (PBM) in the control of dentin hypersensitivity (DH). (C-Shape It).

Methods: 32 subjects with 83 hypersensitive teeth were randomized into four groups (N =8) : GPlacebo - simulated PBM (without light emission) followed by the application of nHAP-free toothpaste; GLaser - PBM followed by the application of nHAP-free toothpaste; GnHAP - simulated PBM followed by the application of nHAP; GLasernHAP - PBM followed by the application of nHAP.

Morphological and chemical effects of in-office and at-home desensitising agents containing sodium fluoride on eroded root dentin.

Objective: The aim of this study was to evaluate the morphological and chemical effect of in-office and at-home desensitising agents containing sodium fluoride (NaF) on eroded root dentine in vitro.

Methods: Fifty bovine dentine samples were pre-eroded and randomised into five groups (n = 10): G1 (Control) - milli-Q water; G2 - fluoride varnish containing NaF 22,500 ppm; G3 - desensitising cream containing NaF 9,000 ppm associated with 20% nanohydroxyapatite; G4 - toothpaste with NaF 5,000 ppm associated to tricalcium phosphate; G5 - toothpaste containing NaF 900 ppm and casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF). The specimens were submitted to erosive challenge for three days.

Effect of the casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) and photobiomodulation (PBM) on dental hypersensitivity: A randomized controlled clinical trial.

Objective: This randomized controlled clinical trial aimed to evaluate the effect of the casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) and photobiomodulation (PBM) in the treatment of dentin hypersensitivity (DH), and the impact of this on the health-related quality of life (HRQL).

Methods: Eighty teeth with DH were randomized into four groups and received three treatment sessions: PLACEBO = placebo + LASER application mimicking; CPP-ACPF = CPP-ACPF + LASER application mimicking; PBM = placebo + LASER active application; CPP-ACPF+PBM = CPP-ACPF + LASER active application. Tactile (exploratory probe) and evaporative (triple syringe) stimuli were used to measure DH and were recorded with the aid of a visual analogue scale (VAS) after the 1st, 2nd and 3rd treatment sessions and one-month follow-up.

Effect of high concentrated fluoride-based dentifrice on the hardness, roughness, and color of the bleached enamel.

Context: Remineralizing agents have been recommended to restore the integrity of bleached enamel.

Aims: The aim of this study was to evaluate the effect of fluoride at high concentration (5000 ppm) applied to bleached enamel.

Materials And Methods: A total of 30 specimens obtained from newly extracted third molars were divided into two groups ( = 15) as follows: control group and fluoride group.

In situ Effect of Nanohydroxyapatite Paste in Enamel Teeth Bleaching.

Aim: Evaluate in situ the effect of nanohydroxyapatite paste (nano-HAP) before bleaching with hydrogen peroxide 35% (HP35%) by ion chromatography (IC) Knoop hardness number (KHN) and tristimulus colorimetry (TC).

Materials And Methods: A total of 60 fragments were obtained from third molars included (3 mm × 3 mm × 3 mm) and the specimens were divided into three groups (n = 20): Gas chromatography (CG) (negative control group) = no bleaching; HP35% (positive control group) = HP35% whitening (whiteness HP35%); nano-HAP = application for 10 minutes before bleaching treatment + HP35%. The specimens were fixed to the volunteers' molars.

Effect of 10% Strontium Chloride and 5% Potassium Nitrate with Fluoride on Bleached Bovine Enamel.

Background: Dental whitening has been increasingly sought out to improve dental aesthetics, but may cause chemical and morphological changes in dental enamel surfaces.

Objective: This study evaluated the effect of 10% strontium chloride and 5% potassium nitrate with fluoride on bovine enamel, through tristimulus colorimetry, Knoop microhardness (KHN), and roughness after bleaching with 35% hydrogen peroxide (HP).

Methods: The specimens were divided into three groups (n=15): GControl received bleaching treatment with 35% HP; GNitrate received bleaching with 35% HP followed by the application of 5% potassium nitrate with 2% sodium fluoride; and GStrontium received bleaching with 35% HP followed by the application of 10% strontium chloride on the enamel.

Randomized clinical trial of the effect of NovaMin and CPP-ACPF in combination with dental bleaching.

Objective: This randomized, controlled, double-blind clinical study evaluated the effect of calcium sodium phosphosilicate (NovaMin) and casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) on the prevention of post-operative sensitivity and on the effects of clinical bleaching treatment.

Material And Methods: Sixty volunteers were selected according to inclusion and exclusion criteria and were randomly assigned into three groups (n=20): CG (control group) patients, who were treated with 35% hydrogen peroxide; NOVAG (NovaMin group) patients, who were treated with 35% hydrogen peroxide followed by the application of NovaMin; and CPPG (CPP group) patients, who were treated with 35% hydrogen peroxide followed by the application of CPP-ACPF. Both bioactive agents were applied for five minutes.