Color change, diffusion of hydrogen peroxide, and enamel morphology after in-office bleaching with violet light or nonthermal atmospheric plasma: An in vitro study.

Objective: The aim is to evaluate the effect of violet light (VL) and nonthermal atmospheric plasma (NTAP) combined with or without 35% hydrogen peroxide (HP) and 37% carbamide peroxide (CP).

Methods: Bovine crowns were divided into (n = 10) VL, VL/HP, VL/CP, NTAP, NTAP/HP, NTAP/CP, HP, CP, and C (control) groups. Color and whiteness change (CIELAB-Δ E CIEDE2000-Δ E , whiteness index-ΔWI ), color parameters (ΔL, Δa, and Δb), and intrapulpal concentration (μL/mL) of HP were assessed by spectrophotometry.

Penetration degree of sealer in artificial lateral canal after passive ultrasonic irrigation with EDTA for different times.

The aim of this study was to evaluate the degree of penetration of obturation cement in artificial lateral canals after Passive Ultrasonic Irrigation (PUI) with ethylenediaminetetraacetic acid (EDTA) for different times. Fifty upper molar palatine roots were used, in which two artificial lateral canals were made at distances of 7 and 3 millimeters from the root apex. After instrumentation and drying the canal, the final toilet stage was performed on five groups (n = 10), as follows: G1 - EDTA 17% + PUI for 10 seconds; G2 - EDTA 17% + PUI for 20 seconds; G3 - EDTA 17% + PUI for 30 seconds; G4 - EDTA 17% + PUI for 60 seconds; G5 - EDTA 17% + activation by instrument R50 for 5 minutes (Control).