What are abfractions?

These are "wear" points at the neck of the tooth , where the enamel has disappeared and dentin is exposed. Dentists used to say that this was strictly caused by toothbrush abrasion and ask people to use a softer toothbrush and not brush so hard, but that is not the primary cause. Enamel at the neck of the tooth is very thin or nonexistent to start with. Teeth tend to experience all sorts of forces (vertical, horizontal,sheer,compressive )including bending forces which are focused at the neck of the tooth where the enamel is thin. So actually the neck is like an expansion joint in a long span bridge. These forces over time cause some loss of enamel adjacent to the neck of the tooth and this allow exposed dentin to erode. The erosion associated with the abfraction continues as long as the dentin is exposed and tends to further undermine the tooth's enamel covering, which leads to further enamel loss. In my office the most frequently placed fillings are done to seal these abfractions and slow down this destructive process.