Changes in physical properties of joined gypsum fragments

(1) The dimensional change in joined fragments of gypsum models was small. The highest percentage occurred with zinc phosphate cement. (2) The cyanoacrylate cements produced the strongest bonds. Mendent Formula VI and the epoxy cement were least effective. (3) The bond strength was generally greater after 24 hours. The exceptions were Mendent Formula VI and zinc phosphate cement. (4) Different gypsum products responded differently to bonding agents. Some are superior for plaster of Paris; others for artificial dental stone.