Microfractures

Microfractures are defined as fine fracture lines in dentine/enamel without the loss of hard tissue. Microfractures in dentine are a rather frequent cause of pulpal irritation. Typically, dentine microfractures cause sharp, momentary pain in the pulp as a result of occlusal activity. The mechanism for the pain is much the same as in dentine hypersensitivity: rapid movement of dentinal fluid causes irritation of the odontoblast/nerve endings complex.

Microfractures are often totally within the tooth structure and do not extend to the surface. However, as time passes they tend to propagate and may become exposed. Microfractures can be diagnosed by selective percussion or pressure of tooth cusps, use of fibreoptics, and by direct observation of cusp/cavity margins after removal of old fillings (see picture above).

Microfractures do not necessarily cause permanent damage to the pulp. Evaluation of results from several clinical tests as well as the dental history are needed to determine whether endodontic treatment is needed.