The diagnosis and treatment of the cracked tooth can present difficulties. The causes of the cracked tooth include masticatory accident, radical preparation and overuse of direct restorative materials, trauma from occlusion, and torque on abutment teeth. Placement of a cast restoration covering the cusp is usually suggested. However, bonded restorations are effective in restoring the strength of teeth weakened by cavity preparation. A material that bonds amalgam to dentin may present a more conservative and less expensive restoration of the cracked tooth.