While there is no question that regular chewing gum promotes tooth decay, there is clinical evidence
that demonstrates just the opposite for sugar-free gum. Studies have shown that using sugar-free chewing gum after meals and snacks, especially when toothbrushing at those times is impractical
helps reduce the acid level and its potential detrimental effect on the enamel. Its mechanism of action is the stimulation of 10 times the normal rate of salivary flow due to both the act of chewing and the flavor of the artificial sweetener (sorbitol or xylitol). The saliva washes away food particles and acid produced by bacteria in the plaque and neutralizes the acid because of increased concentration of bicarbonates. Chewing sugar-free gum is not intended to replace toothbrushing and flossing. Sugar-free gum is also recommended for people with xerostomia (dry mouth) to stimulate increased salivary flow, along with drinking greater amounts of water (6-8 glasses a day). However, those experiencing TMD (temporomandibular joint disorder) symptoms should refrain from chewing any gum.
Source:
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