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Glossary

Bonding

A technique used by dentists to firmly attach fillings, crowns, inlays, onlays and veneers to the teeth. Virtually all bonding systems combine the following steps: An acid solution is applied to the tooth to produce a microscopically roughened surface. Under a microscope, acid-etched tooth structure resembles Velcro®, with linear filaments projecting from the tooth surface.

View animation Cavities, Fillings and Core Buildups

Dental acid etch solution is used to prepare enamel and dentin as the first step in the bonding process.

Figure 1: Dental acid etch solution is applied to the prepared enamel and dentin as the first step in the bonding process. Often, a de-sensitizing agent will be applied to the prepared dentin prior to acid etching.

A liquid adhesive solution is applied, which contains long strands of resin "polymers" that entangle themselves among the linear filaments of enamel. When the polymer strands of the dental adhesives are exposed to light of a certain wavelength, they begin to form molecular bonds (or "cross-links") with one another, effectively locking themselves in among the enamel filaments. "Tails" of the polymer strands are left protruding from the tooth's surface on every wall of the prepared tooth.

The dental restoration (filling, crown, etc.) is also treated to produce a similar surface. When the restoration is placed in the tooth and exposed to the polymerizing light (or "curing light"), the polymer strands from the tooth and restoration cross-link, producing an ultra strong chemical bond. Different materials have been developed to enhance the process, but they all work in essentially this way.

A dental curing light produces blue wavelength light to cure the photopolymer composite resin filling.

Figure 2: A blue light source (approximately 460 nanometer wavelength) is used to harden tooth-colored, composite resin filling material in these lower molar teeth.

Bonding has ushered in a new era of "minimally invasive" dentistry, in which teeth can now be fixed without the need to cut away healthy tooth structure, just to hold a filling or crown onto the tooth.
Learn more: Procedures › Crowns
Learn more: Procedures › Fillings & core buildups
Learn more: Procedures › Inlays
Learn more: Procedures › Onlays
Learn more: Procedures › Veneers