Works of art are subject to a variety of disfiguring ills, many caused by environmental effects, changes in temperature and humidity, in particular, as well as pollution. Art conservation and Art sculpture restoration is the preservation of structurally sound works of art by slowing or stopping altogether the processes that lead to the damage of works of art; as well as the repair of already damaged works of art.
Sculpture that stands outdoors is more vulnerable to environmental changes. The best means to preserve sculpture would be to put it in a temperature and humidity controlled situation. Broken sculpture can be repaired by using clear, cold-setting adhesives or by means of dowelling. Large metal sculptures are held together with metal dowels, mostly with copper, stainless steel, or brass.
Stone sculpture may require periodic cleaning: steam, spray, or trickled water is most often used. Soap, not detergent, is also suitable
Other types of sculpture such as wood, and metal, are vulnerable to environmental changes as well. Wood sculpture is also dowelled and special cements can be used to fill cracks. Wood is also vulnerable to woodworm and dry rot and may have to be treated with insecticide and fungicide. Sometimes, badly decayed wood pieces can be preserved by means of impregnation with a plastic medium. Cracks in metal sculpture can be filled with special adhesives. Metal sculpture may be waxed to protect it from atmospheric corrosives. While bronze acquires a patina that is considered aesthetically pleasing, whereas on metals like lead a patina will lead to eventual decay.