History and selection of dental materials History1. Ancient times to the 1700 sWhy are certain materials chosen instead of others to serve as dental restorative materials? Acthually, much has been learned throught history by trial and error. In acient times,gold wasused not only for its workability or ease of processing. Long ago,artist learned to form gold into many shapes/ the rlationship between the art and science of dentistry dates back to the infancy of the profession. Remember that for centuries humans have attempted to improove their apperance with adornments, such as jewelry and makeup. The replacement of lost teeth is also an ancient practice. At the time,it was more likely for esthetics than for function. As dentistry developed throughout the ages,more and more materials were used. Some off these included :a. Lvory,which was carvedb. Porcelain,which was fired into tooth shapesc. Wax and gypsum, which were used for impressions and modelsd. Zinc oxide-eugenol and zinc phosphate,which evolved as fillings and cements to glue the restoration to the tooth2. The 1800sBy this time, dentistry was becoming a scientifically based discipline. The pace of development of new materials quickened. Amalgam, a silver filling material, was wiely accepted and frequenly used. Porcelain was also used for inlays and crowns.3. The 20th centurya. Dental materials science has now developed into its own discipline. New material and techniques are constantly being developed.b. A variety of cast metals are used. Alloys are made of gold, chromium and nickle, chromium an cobalt,and titanium. Cast metals are used for crowns,bridges, and partial dentures.c. Polymers and composites are alternatives for nearly every dental materials need.d. The pace of dental materials development is so fast, some of this text will be outdated before it is published.e. Luckily, the basic concepts of materials science and their use do not change. Both the student and the practitioner need to understand te behavior of the materials they use. After all, they are the ones who must select a product from a rather long list of possibilities.