This study evaluated the effect of 10% carbamide peroxide (CP) bleaching on Knoop surface microhardness (KHN) and morphology of sound enamel and enamel with early artificial caries lesions (CL) after pH-cycling model (pHcm). Human dental enamel blocks were randomly divided into 6 groups (n=10): 1 - sound enamel bleached (S) with CP (Rembrandt/Den-Mat); 2 - S and submitted to pHcm; 3 - CL bleach...

The present study evaluated transenamel and transdentinal penetration of hydrogen peroxide during tooth whitening recognized in altered enamel by the presence of cracks or microabrasion. We used 72 experimental units (n=20) obtained from bovine incisors: GI-sound enamel; GII-teeth showing visible enamel cracks (4 mm to 5.7 mm in length); and GIII-microabrasioned enamel. The 12 remaining specime...

AIM The goal of this study was to fnd a method to eliminate bond strength reduction after vital bleaching. MATERIALS AND METHODS Sixty fat surfaces of enamel central human incisors were prepared by diamond disks. In the frst group, the samples immediately bonded to the tooth after bleaching. For the second group, the bleached samples were treated by sodium ascorbate for 1 hours. In the third ...

This study sought to evaluate the microhardness of enamel submitted to 10% carbamide peroxide treatment and different methods of remineralization involving sodium fluoride (NaF). Non-erupted third molars were used and 75 enamel blocks with standardized dimensions (4.0 x 4.0 x 2.0 mm) were obtained. Enamel blocks were randomly divided into five groups (n = 15): one control (no bleaching and no f...

The aim of this study was to evaluate the effect of bleaching and thermocycling on microshear bond strength of bonded resin composites to enamel. Enamel slices were prepared from ninety-six intact human premolars and resin composite cylinders were bonded by using Adper Single Bond 2 + Filtek Z350 or Filtek silorane adhesive and resin composite. Each essential group was randomly subdivided to tw...

AIM The aim of this in vitro study was to evaluate the surface roughness and hardness of both unbleached and bleached (opalescence; 10% carbamide peroxide) human enamel brushed with water (without dentifrice), fluoride abrasive dentifrice (Colgate Total) and whitening dentifrice (Natural White). MATERIALS AND METHODS Human enamel samples were obtained from third molars and randomly divided in...

BACKGROUND To determine the susceptibility of teeth for repigmentation after bleaching. MATERIALS AND METHODS Forty premolars were assigned to three groups (n = 12). Group 1 was bleached using 30% w/v hydrogen peroxide 15 min 3 times a day every other day for 4 days. In Group 2 was bleached using 16% carbamide peroxide (Polanight), 90 min a day for 15 days. 2 days later, the shades of the ble...

Objective: The objective of this in vitro study is to examine the effect antioxidants on bonding strength composite resin bleached enamel. Materials and Methods: One hundred twenty non decay teeth were used study. Specimens cut from enamel cement junction. Then specimens randomly assigned into two groups-office bleaching home bleaching. Bleaching applied first 12 subgroups. remaining groups kep...

Vital teeth tend to present color changes that compromise esthetics substantially. These discolorations can be extrinsic or intrinsic according to the location and the cause of the stain. Many dentists have indicated the treatment of intrinsic discolorations with bleaching agents. Thanks to innovations in bleaching agents, tooth whitening has become more and more popular among dental profession...