Internal Tooth Whitening

Excerpt

Tooth discoloration is a common complaint among patients seeking to improve the aesthetics of their anterior teeth. Tooth discoloration or stains are described as a change in color or translucency of 1 or more teeth. Depending on the etiology and location, tooth stains can be extrinsic or intrinsic. Understanding the specific etiology is crucial for determining the most appropriate treatment plan.

Extrinsic stains result from the accumulation of pigments on the enamel surface, caused by pigmented foods and beverages, such as coffee, tea, and wine, as well as lifestyle habits, such as tobacco smoking. Intrinsic stains occur within the enamel or underlying dentine, originating during tooth development, such as in cases of dental fluorosis and amelogenesis imperfecta, or appearing after tooth eruption due to factors such as pulpal trauma, necrosis, or the remnants of endodontic materials.

Internal tooth whitening is a conservative procedure that improves the appearance of nonvital teeth with internal discoloration without requiring the loss of additional tooth structure. This procedure is also more economical compared to traditional treatments such as veneers or crowns. This procedure uses oxidizing agents to penetrate dental tissues and degrade organic pigments, thereby whitening the tooth structure. The most common whitening agents are hydrogen peroxide and carbamide peroxide.

The most commonly used methods for bleaching nonvital teeth include the walking bleach technique, inside-outside bleaching, and in-office bleaching. The walking and inside-outside bleaching techniques are reported to be similarly effective for internal bleaching. The walking bleach approach is preferred as the access cavity is sealed, thereby avoiding the need for trays at home. In contrast, the success of the inside-outside technique depends on patient compliance with using bleaching trays and cleaning the access cavity with an interdental brush between office visits. The results of internal bleaching are more predictable in discolored teeth caused by trauma or necrosis than material-related tooth discoloration.

This activity reviews the factors involved in planning and performing internal tooth whitening and presents a case study of a 28-year-old man who underwent internal whitening of a nonvital upper central incisor using the walking bleach technique.