To review history of gutta percha and its molecular chemistry
- The Malays and Chinese are said to have used it first.
- In Europe (in the middle of the 7th century), John Trandescant wrote in his book “The playable mazer wood, being warmed in water, will-work to any form.” This was thought to apply to gutta-percha.
- In the early 1840’s it was reintroduced into Europe, under the name gutta-percha.
- GP was also used in the manufacturing of cements, surgical & Musical instruments, paper, maps, and boats. Rubber soon dispelled the gutta-percha illusion.
- GP, the naturally occurring polymer of isoprene, has been known to dentistry for almost 125 years.
- Natural rubber & GP both are high-molecular-weight polymers, and structured from the same basic building unit or isoprene
- GP exists in the trans state, meaning the CH2 groups are on opposite sides of the isoprene chains, resulting in a more linear arrangement. This gives GP harder, more brittle and less elastic properties
- In 1942 C.W. Bunn explained how GP can exist in 2 different crystalline forms, alpha & beta.
- The alpha state is the natural form, and when heated above 65o C it turns amorphous. If cooled slowly at 0.5o C/hr it can return to the alpha form, and if not it turns into the commercial beta form.
- Beta GP becomes amorphous at 56 C.
- The main difference between the two structures is the molecular repeat distance, which is smaller with the beta form.
An important background information of the history and molecular chemistry of gutta-percha.