C-factor is short for “configuration factor,” a way to describe the shape of a dental cavity in terms of bonding surfaces. It is the ratio of bonded surfaces to unbonded (free) surfaces in a tooth preparation.

New mathematical models have been developed to refine C-factor. The configuration factor (C-factor) is an index used to evaluate the relationship between cavity configuration and the development of polymerization shrinkage stress in dental restorations.

Configuration factor, also called C-factor, is most simply described as the ratio of bonded to unbonded surfaces. While this definition is taught in dental school, few dentists are equipped to mitigate C-factor stresses in their dental restorations.

In dentistry, the configuration factor (or c-factor) refers to the number of bonded surfaces in an adhesive dental restoration.

We have reviewed the role of C-factor as a “rule of thumb” as well as the applications and limitations of the C-factor in stress analysis of dental restorations.

Although C-factor has been widely researched, its correlation with stress analysis in dental restorations remains controversial. This review aims to discuss the application and limitations of C-factor and define the restricted conditions under which the C-factor "rule of thumb" is applicable.

What is the role of fibre in controlling C-Factor? By placing a fibre insert, such as Ribbond, on the pulpal and/or axial walls, stress on the developing dentin bond and the maturing hybrid layer is reduced, as the Ribbond fibres have been shown to deform under polymerization stress.

If the C-factor is more than 1, adhesion should not be maintained with conventional adhesives alone. In these cases, adhesive linings, different formulations of resin, and curing methods are used. The higher the C-value, the greater the polymerization shrinkage.

Als je de bonding aan dentine langer de tijd geeft (5-30 minuten), dan zal dit resulteren in een lage C-factor. Dit betekent dat je de eerste 5 minuten niet meer dan 1,5mm aan massa restauratiemateriaal zou moeten aanbrengen (De Alleman-Deliperi regel).

Summary – What is C-Factor? C-Factor (Configuration Factor) is the ratio of bonded to unbonded surfaces in a cavity. Higher C-Factors result in higher stresses. The successful understanding and management of C-Factor forms a key part of Biomimetic Dentistry. Learn about C-Factor…