Explanation: Latex.Chewing gum is a type of gum made of chicle, a natural latex product, or synthetic rubber known as polyisobutylene. Sugar-free gum sweetened with xylitol has been shown to reduce cavities & plaque. Most chewing gums are considered polymers. The sweetener sorbitol has the same benefit, but is only about one-3rd as effective as xylitol. Xylitol is specific in its inhibition of Streptococcus mutans, bacteria that are significant contributors to tooth decay.