Australian Dental Council (ADC) Practice Test

Sucrose is considered the most cariogenic sugar due to its unique chemical structure and the way it is metabolized by oral bacteria. When sucrose is consumed, it readily ferments and is utilized by cariogenic bacteria, particularly Streptococcus mutans, which are responsible for the initiation and progression of dental caries. The fermentation of sucrose leads to the production of acids, which lower the pH in the oral environment and promote demineralization of tooth enamel.

Sucrose also enhances the adhesion of bacteria to the tooth surface and contributes to the formation of dental plaque. Its prevalence in many foods and beverages, especially processed items, increases its exposure among individuals, further enhancing its cariogenic potential. Other sugars like glucose, fructose, and galactose are less effective at promoting caries activity compared to sucrose because they do not contribute to plaque formation and acid production to the same extent.

In summary, sucrose's ability to foster a favorable environment for acid-producing bacteria, its role in plaque development, and its widespread presence in the diet make it the most cariogenic sugar.