Questions and Correct Answers (Professor Verified) | Latest
Edition
Question 1:
Which of the following bacteria is most commonly associated with the initiation of dental caries?
A) Streptococcus mutans
B) Lactobacillus acidophilus
C) Actinomyces viscosus
D) Porphyromonas gingivalis
Correct Answer: A
Rationale: Streptococcus mutans plays a primary role in the initiation of dental caries due to its
ability to metabolize sugars into acids that demineralize enamel. Lactobacillus acidophilus
contributes more to lesion progression once established; Actinomyces viscosus is associated
with root caries in older adults; Porphyromonas gingivalis is primarily linked to periodontal
disease and anaerobic infections.
Question 2:
Under which classification of gingival diseases and conditions is puberty-associated gingivitis
found?
A) Non-plaque-induced gingival lesions
B) Plaque-induced gingival diseases modified by systemic factors
C) Gingival diseases of specific bacterial origin
D) Gingival diseases of viral origin
Correct Answer: B
Rationale: Puberty-associated gingivitis is classified as a plaque-induced gingival disease
modified by systemic factors, such as hormonal changes during puberty that exacerbate plaque
response. A refers to lesions from trauma or foreign bodies; C to specific pathogens like
streptococci; D to viral infections like herpes.
Question 3:
A patient presents with a short, thick lingual frenum that results in limited tongue movement
affecting speech. Which is the most likely diagnosis of this condition?
A) Ankyloglossia
B) Fordyce granules
C) Geographic tongue
,D) Fissured tongue
Correct Answer: A
Rationale: Ankyloglossia, or tongue-tie, is characterized by a short, thick lingual frenum
restricting tongue mobility, impacting speech and oral hygiene. B are ectopic sebaceous glands;
C is a benign inflammatory condition; D involves deep grooves on the tongue surface.
Question 4:
Which tooth structure is least likely to be viewed on a dental radiograph?
A) Enamel
B) Dentin
C) Cementum
D) Pulp
Correct Answer: C
Rationale: Cementum has a density similar to surrounding bone, making it radiographically
invisible. Enamel appears radiopaque (white); dentin less so but visible; pulp is radiolucent
(dark) due to soft tissue.
Question 5:
The junction of a buccal and lingual triangular ridge is known as:
A) Transverse ridge
B) Oblique ridge
C) Marginal ridge
D) Cusp ridge
Correct Answer: A
Rationale: The transverse ridge forms where buccal and lingual triangular ridges meet,
providing structural support in molars. B is specific to maxillary molars; C borders the occlusal
surface; D refers to cusp slopes.
Question 6:
Which ethical principle does informed consent uphold?
A) Autonomy
B) Beneficence
C) Nonmaleficence
D) Justice
Correct Answer: A
,Rationale: Informed consent respects patient autonomy by allowing self-determination in
treatment decisions. Beneficence promotes good; nonmaleficence avoids harm; justice ensures
fairness.
Question 7:
According to the classification system of the American Academy of Periodontology, generalized
aggressive periodontitis is classified as:
A) Type I
B) Type II
C) Type III
D) Type IV
Correct Answer: C
Rationale: Type III includes aggressive periodontitis, characterized by rapid attachment loss.
Type I is prepubertal; Type II chronic; Type IV systemic associations.
Question 8:
Which hypersensitivity reaction is an allergy to natural rubber latex in examination gloves?
A) Type I
B) Type II
C) Type III
D) Type IV
Correct Answer: A
Rationale: Type I is immediate IgE-mediated, causing anaphylaxis to latex. Type II cytotoxic;
Type III immune complex; Type IV delayed cell-mediated.
Question 9:
Which condition is treated with nystatin?
A) Candidiasis
B) Tuberculosis
C) Actinomycosis
D) Dental caries
Correct Answer: A
Rationale: Nystatin is an antifungal for oral candidiasis (thrush). B requires antitubercular drugs;
C sulfonamides; D antimicrobials like fluoride.
Question 10:
Which describes the junction of two surfaces of a crown?
, A) Point angle
B) Line angle
C) Cementoenamel junction
D) Dental enamel
Correct Answer: B
Rationale: Line angle is the junction of two crown surfaces, like mesio-occlusal. Point angle is
three surfaces; cementoenamel junction is root-crown boundary; enamel is the hard tissue.
Question 11:
A kVp below 65 should not be used for dental imaging because:
A) Image contrast is decreased
B) Patient exposure to radiation is increased
C) Film speed is reduced
D) Scatter radiation is minimized
Correct Answer: B
Rationale: Low kVp increases radiation dose to achieve adequate penetration. Higher kVp
reduces dose; contrast is higher at low kVp.
Question 12:
Which agency is a federal agency that enforces workplace safety?
A) OSHA
B) EPA
C) FDA
D) CDC
Correct Answer: A
Rationale: OSHA enforces workplace safety standards, including in dental settings. EPA
regulates waste; FDA drugs/devices; CDC guidelines.
Question 13:
Which agency protects employees by improving engineering controls and enforcing PPE?
A) NIOSH
B) OSHA
C) ADA
D) ADHA
Correct Answer: A