0000000000210378
AUTHOR
José Amengual
The Use of Atomic Force Microscopy in Determining the Stiffness and Adhesion Force of Human Dentin After Exposure to Bleaching Agents
Introduction: Oxidant bleaching agents may induce several alterations on mineralized teeth tissues. Our aim is to study,at the ultrastructurallevel,mechanicalmodifications induced on dentin after exposure to different bleaching agents.Methods: Nanoindentation performed with atomic force microscopy was used to measure changes in dentin stiffness as well as the adhesion force between the tip and the tissue both in intertubular and peritubulardentin.Foreachspecimen,dentinlocalization, and bleaching agent, 100 independent nanoindentations were performed. Carbamide peroxide (30%) and hydrogenperoxide(35%) wereusedasbleaching agents. Results: A significant reduction of both stiffness and adhesion…
Toothguide Training Box for Dental Color Choice Training
The purpose of this study was to evaluate the use of the Toothguide Training Box (TTB) for training dental students in color identification. The seventy-four volunteers who took part in the study attended a seminar on the Vita 3D Master Guide (MG) and the TTB system as well as a demonstration of the equipment before training began. At the end of the training they took the TTB final test. In addition, the participants were asked to recognize ten MG shade tabs in a blind manner before and after TTB training. The training times and percentages of correct answers were compared using the paired t-test. Variations in scores with training times and percentages of correct answers before and after t…
Clinical efficacy of a bleaching enzyme-based toothpaste. A double-blind controlled clinical trial.
Abstract Objectives To assess the efficacy of a bleaching enzyme-based toothpaste. Material and methods A randomized clinical trial was carried out, comprising 48 participants with teeth exhibiting color A3 or higher according to the Vita Classical guide. One-half of the sample received the bleaching enzyme-based toothpaste (White Kin ® ), while the other received placebo toothpaste. Both products were supplied in identical containers and had the same composition except for the active components. The teeth color was measured with a spectrophotometer. The patients were instructed to brush their teeth three times a day during 3 min with the assigned product, during 12 weeks. The color measure…
In vitro evaluation of the efficacy of two bleaching procedures
Objective: In vitro comparison of the efficacy of two bleaching procedures, one based on carbamide peroxide (CP) and the other on hydrogen peroxide (HP), simulating clinical conditions. Study Design: Two groups of 20 teeth in each group were selected. Group A: 22% CP, one hour a day for 21 consecutive days. Group B: 37.5% HP, in 2 treatment sessions with an one week interval between each session. At each session the product was applied three successive times for eight minutes. Colour was recorded before treatment, when it was finished and one week after finishing it, with the Vita EasyShade spectrophotometer. CIEL*a*b* and ΔE were established at each moment in the study. Intra-group data wa…
Sealing capacity of a photochromatic flowable composite as protective base in nonvital dental bleaching.
Aim To evaluate microleakage of a flowable composite used as a protective isolating base, applied with different adhesive systems. Methodology Seventy root-filled teeth were divided into seven groups. A flowable composite base (Tetric Flow Chroma) was used with three adhesive techniques (Syntac, Excite, Excite DCS; in the three cases with and without acid etching) and in a control group without dentine conditioning or adhesive placement. A 30% hydrogen peroxide solution was applied for 24 h in the pulp chambers, followed by the placement of a dye (silver nitrate) for 4 h. Each tooth was sectioned longitudinally, and examined under 4× magnification to assess the tooth/restoration dye leaka…
Reliability of Two Color Selection Devices in Matching and Measuring Tooth Color
ABSTRACT Objective The objective of this study was to investigate the intra and interdevice reliability of two tooth color measurement devices: EasyShade (ES) and SpectroShade Micro (SSM). Materials and methods Tooth color was measured in six maxillary and mandibular. L*, a* and b* values and shade matches to VITA Classical and Vitapan 3D-Master shade guide systems were determined for all teeth. ÄE was assessed. Paired t-test and correlation coefficient (ICC) were used. Results Intradevices no significant differences (p > 0.05) were found between L*, a*, b*. Interdevice L* and b* were significantly higher for ES (p < 0.05), while a* was significantly higher for SSM (p < 0.05). ÄE s…