Macrophotograph of an extracted molar (male, upper, number 7), sectioned with a glass cutting wheel. A root was broken during extraction. The molar shows two amalgam fillings, a powdered alloy consisting of silver, tin, copper & zinc mixed with mercury. The decayed area is removed & the cavity lined with a white filler (seen), which protects the base of the cavity from the effects of the filling itself. The open channel running up the root & across the tooth is the dental pulp containing blood vessels, nerves & lymphatics. A layer of enamel covers the crown, beneath which is the dentine (both seen here) running down the roots. Magnification:X 1.4 (at 35mm size).