Old bones are brittle.
D000818:Animals; D003824:Denture, Complete; D003829:Denture, Partial; D003778:Dentures / Q000266:history*; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D014070:Tooth; D014093:Tooth, Artificial