Internal Tooth Whitening

Excerpt

Tooth discoloration is a common complaint in patients seeking to improve the aesthetics of the anterior teeth. Tooth discoloration or stains are described as the change of 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 to determining the most appropriate treatment plan.

Extrinsic stains result from the accumulation of pigments on the enamel surface. Pigmented foods and beverages, including coffee, tea, and wine, and lifestyle habits like tobacco smoking cause extrinsic stains.

Intrinsic stains occur within the enamel or underlying dentine. They may originate during tooth development, like dental fluorosis and amelogenesis imperfecta, or appear after tooth eruption due to pulpal trauma, necrosis, or the remains of endodontic materials.

Internal tooth whitening is a conservative procedure that improves the appearance of nonvital teeth with internal tooth discoloration, does not require the loss of additional tooth structure, and is economical compared to traditional treatment with a fixed restoration, like a veneer or crown. The procedure uses oxidizing agents to penetrate the dental tissues and degrade organic pigments, 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 techniques are reported to be similarly effective for internal bleaching. The walking-bleach approach is preferred as the access cavity is sealed, avoiding the need for trays at home. By 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 reports the case of the internal tooth whitening of a nonvital upper central incisor in a 28-year-old man using the walking-bleach technique.