HESI
Dental Hygiene Case Studies 2026 | Clinical Case Study
Questions, Answers & Detailed Rationales | Exam Prep
FEATURES
✓ HESI Dental Hygiene Case Studies 2026
✓ Clinical Scenariles
✓ Dental Hygiene Clinical Reasoning
, HESI Dental Hygiene Case Studies 2026 |
Clinical Case Study Questions, Answers &
Detailed Rationales | Exam Prep
Case 1
1. Which bacteria are predominately found close to the pulp in the
carious lesion on tooth #14?
A. Streptococcus mutans
B. Lactobacillus
C. Actinomyces viscosus
D. Fusobacterium
Correct Answer: B. Lactobacillus
Rationale: Lactobacillus species are predominantly found in advanced
carious lesions close to the pulp. While Streptococcus mutans is
associated with the initiation of caries, Lactobacillus is more prevalent
in deeper, more advanced lesions due to its aciduric nature.
2. Which clinical characteristic indicates the presence of subgingival
calculus?
,A. Presence of supragingival calculus
B. Presence of diastemas
C. Bluish-red marginal gingiva
D. Attachment loss
Correct Answer: C. Bluish-red marginal gingiva
Rationale: Subgingival calculus is typically dark and hard, and its
presence often causes a bluish-red discoloration of the marginal gingiva
due to the irritation and inflammation it causes beneath the tissue. This
color change is a key clinical indicator of subgingival deposits.
3. Radiographically, what is the radiopaque structure posterior to
tooth #31?
A. Internal oblique ridge
B. Mandibular canal
C. External oblique ridge
D. Retromolar pad
Correct Answer: A. Internal oblique ridge
Rationale: The internal oblique ridge (also called the mylohyoid ridge)
appears as a radiopaque line in the posterior mandible, running
, downward and forward from the ramus. It is located posterior to the
third molar region.
4. Which explains the distobuccal probing depths on tooth #13?
A. Keratinized tissue associated with tobacco use
B. Presence of radicular calculus
C. Gingival enlargement
D. Periodontal health
Correct Answer: B. Presence of radicular calculus
Rationale: Radicular (subgingival) calculus is a local factor that
contributes to periodontal pocket formation and increased probing
depths. It causes inflammation and attachment loss, leading to deeper
probing depths.
5. The patient is scheduled to have tooth #14 extracted. Which
prophylactic oral antibiotic drug regimen should be prescribed for this
procedure?
A. Cephalexin 2 grams one hour prior
B. Cephalexin 2 grams one hour before and after
C. Amoxicillin 2000 milligrams one hour before and after
D. Amoxicillin 2000 milligrams one hour prior
Dental Hygiene Case Studies 2026 | Clinical Case Study
Questions, Answers & Detailed Rationales | Exam Prep
FEATURES
✓ HESI Dental Hygiene Case Studies 2026
✓ Clinical Scenariles
✓ Dental Hygiene Clinical Reasoning
, HESI Dental Hygiene Case Studies 2026 |
Clinical Case Study Questions, Answers &
Detailed Rationales | Exam Prep
Case 1
1. Which bacteria are predominately found close to the pulp in the
carious lesion on tooth #14?
A. Streptococcus mutans
B. Lactobacillus
C. Actinomyces viscosus
D. Fusobacterium
Correct Answer: B. Lactobacillus
Rationale: Lactobacillus species are predominantly found in advanced
carious lesions close to the pulp. While Streptococcus mutans is
associated with the initiation of caries, Lactobacillus is more prevalent
in deeper, more advanced lesions due to its aciduric nature.
2. Which clinical characteristic indicates the presence of subgingival
calculus?
,A. Presence of supragingival calculus
B. Presence of diastemas
C. Bluish-red marginal gingiva
D. Attachment loss
Correct Answer: C. Bluish-red marginal gingiva
Rationale: Subgingival calculus is typically dark and hard, and its
presence often causes a bluish-red discoloration of the marginal gingiva
due to the irritation and inflammation it causes beneath the tissue. This
color change is a key clinical indicator of subgingival deposits.
3. Radiographically, what is the radiopaque structure posterior to
tooth #31?
A. Internal oblique ridge
B. Mandibular canal
C. External oblique ridge
D. Retromolar pad
Correct Answer: A. Internal oblique ridge
Rationale: The internal oblique ridge (also called the mylohyoid ridge)
appears as a radiopaque line in the posterior mandible, running
, downward and forward from the ramus. It is located posterior to the
third molar region.
4. Which explains the distobuccal probing depths on tooth #13?
A. Keratinized tissue associated with tobacco use
B. Presence of radicular calculus
C. Gingival enlargement
D. Periodontal health
Correct Answer: B. Presence of radicular calculus
Rationale: Radicular (subgingival) calculus is a local factor that
contributes to periodontal pocket formation and increased probing
depths. It causes inflammation and attachment loss, leading to deeper
probing depths.
5. The patient is scheduled to have tooth #14 extracted. Which
prophylactic oral antibiotic drug regimen should be prescribed for this
procedure?
A. Cephalexin 2 grams one hour prior
B. Cephalexin 2 grams one hour before and after
C. Amoxicillin 2000 milligrams one hour before and after
D. Amoxicillin 2000 milligrams one hour prior
