Dental Hygiene Board Licensure Exam

Dental Hygiene Board Licensure Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• Which of the following is the primary cause of dental caries?
• Staphylococcus aureus
• Streptococcus mutans
• Porphyromonas gingivalis
• Candida albicans

Rationale: Streptococcus mutans is the main bacteria involved in the

initiation of dental caries due to its acidogenic and aciduric properties.

2. The most effective way to prevent dental caries is:

• Brushing once daily
• Fluoride application
• Mouth rinses only
• Chewing gum 1 / 4

Rationale: Fluoride strengthens enamel, promotes remineralization, and

inhibits demineralization, making it the most effective preventive measure.

3. The primary purpose of dental sealants is to:

• Whiten teeth
• Treat cavities
• Prevent pit and fissure caries
• Reduce halitosis

Rationale: Sealants provide a physical barrier over occlusal surfaces to

prevent bacterial colonization and caries formation.

4. The most common site for oral cancer is:

• Tongue and floor of the mouth
• Buccal mucosa
• Lower lip
• Palate

Rationale: The lower lip is frequently exposed to sunlight and trauma,

making it the most common site for oral cancer.

5. The basic unit of the periodontal ligament is the:

• Enamel rod
• Collagen fiber
• Cementocyte
• Osteoblast

Rationale: Collagen fibers form the functional unit of the periodontal

ligament, connecting cementum to alveolar bone. 2 / 4

• Which nutrient deficiency is most commonly associated with delayed

wound healing in the oral cavity?

• Vitamin A
• Vitamin D
• Vitamin C
• Iron

Rationale: Vitamin C is essential for collagen synthesis, and deficiency can

lead to delayed wound healing and bleeding gums.

• Which type of fluoride application is professionally applied and not

intended for home use?

• Fluoridated toothpaste
• Fluoride mouth rinse
• Fluoride varnish
• Fluoride tablets

Rationale: Fluoride varnish is a high-concentration professional application

for caries prevention.

8. The “free gingival margin” refers to:

• The alveolar bone surrounding the tooth
• The junctional epithelium
• The edge of the gingiva that surrounds the tooth but is not attached
• The gingival sulcus base

Rationale: The free gingival margin is the unattached edge of the gingiva

around the tooth. 3 / 4

9. The most effective method for removing supragingival plaque is:

• Mouth rinse
• Dental floss
• Toothbrushing
• Chewing gum

Rationale: Toothbrushing mechanically removes plaque from accessible

tooth surfaces, especially supragingival areas.

• Which of the following is considered a Class II caries according to G.V.

Black’s classification?

• Caries on the occlusal surface of molars
• Caries on the cervical third of anterior teeth
• Caries on the proximal surfaces of posterior teeth
• Caries on the incisal edge of anterior teeth

Rationale: Class II caries involve the proximal surfaces of posterior teeth,

commonly treated with restorations.

• Which antiseptic is commonly used in mouth rinses to reduce plaque

and gingivitis?

• Hydrogen peroxide
• Sodium fluoride
• Chlorhexidine gluconate
• Alcohol

Rationale: Chlorhexidine gluconate is a broad-spectrum antiseptic effective

in plaque and gingivitis control.

• / 4