Graded changes in enamel component volumes resulted from a short tooth bleaching procedure

Area of Science:

• Dental Biomaterials
• Enamel Microstructure
• Cosmetic Dentistry

Background:

• Dental bleaching is a common cosmetic procedure.
• Understanding its effects on tooth enamel is crucial for safety and efficacy.

Purpose of the Study:

• To investigate how enamel component volumes and permeability change after a short bleaching procedure.
• To determine if these changes follow a gradient from the outer to inner enamel.

Main Methods:

• Human third molars were subjected to a single bleaching session.
• Enamel sections were analyzed for mineral, organic, and water volumes, and permeability.
• Measurements were taken at varying distances from the enamel surface.

Main Results:

• Significant tooth shade changes were observed after bleaching.
• Enamel composition changes, including mineral loss and organic gain, were most prominent in the outer enamel layers.
• A strong correlation was found between component volume changes and distance from the enamel surface.

Conclusions:

• Short bleaching procedures induce compositional changes in enamel.
• These changes exhibit a gradient, decreasing from the outer enamel surface inward.
• Mineral loss, organic gain, water gain, and permeability decrease follow this gradient.