Which statement best describes a healthy oral microbiome?

• A. Beneficial bacteria outnumber harmful ones
• B. Harmful bacteria outnumber beneficial ones
• C. Bacteria are absent
• D. Only fungi present

Answer: (A)

A healthy oral microbiome thrives when beneficial bacteria predominate over harmful ones. Good microbes help by occupying niches and competing for resources, producing substances that inhibit pathogens, and supporting the local immune defense. This balance keeps biofilm formation and acidity in a healthier range, protecting teeth and gums. If harmful bacteria outnumber beneficial, the ecosystem becomes imbalanced (dysbiosis), increasing the risk of caries and gum disease. Bacteria absent isn’t realistic in a healthy mouth, and having only fungi misses the important protective roles that bacteria provide.