ILLINOIS DENTAL HYGIENIST EXAM – PRACTICE QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS)
PLUS RATIONALES 2026 Q&A | INSTANT DOWNLOAD PDF.
Core Domains
1. Patient Assessment and Dental Hygiene Diagnosis
2. Preventive and Therapeutic Oral Care
3. Periodontal and Hard Tissue Evaluation
4. Radiography and Diagnostic Imaging
5. Pharmacology and Pain Management
6. Legal, Ethical, and Regulatory Standards (IL State Specific)
7. Infection Control and Safety Protocols
8. Community Oral Health and Patient Education
Introduction
This examination is designed to evaluate the foundational and applied competencies required for licensure as a
dental hygienist in Illinois. It assesses knowledge in patient assessment, clinical procedures, radiography,
periodontics, pharmacology, infection control, and state-specific legal and ethical standards. Questions include
,multiple-choice and scenario-based items that emphasize real-world clinical decision-making, critical thinking,
and adherence to professional regulations. Successful candidates demonstrate the ability to integrate theory with
practical application, ensuring safe, effective, and patient-centered care across diverse populations and settings.
SECTION ONE: QUESTIONS 1–100
Question 1
A 45-year-old patient with a history of hypertension controlled with lisinopril presents for a prophylaxis. Which
finding requires immediate medical consultation before proceeding?
A. Blood pressure 118/76 mmHg
B. Dry hacking cough for six weeks
C. Gingival enlargement in mandibular anterior area
D. Heart rate 88 bpm
🟢B
🔴 RATIONALE: Lisinopril (an ACE inhibitor) commonly causes a persistent dry cough. While not life-
threatening, the cough should be evaluated to rule out other causes or medication change. The gingival
enlargement is more consistent with nifedipine or phenytoin, not lisinopril. BP and heart rate are normal.
,Question 2
According to the Illinois Dental Practice Act, a dental hygienist may perform local infiltration anesthesia under
which condition?
A. Without any supervision after passing the clinical exam
B. Only with a dentist physically present in the operatory
C. Under general supervision with prior written authorization
D. Only after completing a board-approved nitrous oxide course
🟢C
🔴 RATIONALE: Illinois law permits dental hygienists to administer local infiltration anesthesia under general
supervision if the dentist has given prior written authorization and the hygienist has completed accredited
training. Physical presence is not required for infiltration.
Question 3
Which of the following is the MOST appropriate for removing tenacious calculus from a moderate furcation
involvement on a mandibular first molar?
A. Universal curette
B. Periodontal file
, C. Sickle scaler
D. Ultrasonic scaler with a standard tip
🟢B
🔴 RATIONALE: Periodontal files are specifically designed to crush and remove tenacious calculus in furcations
and deep pockets. Universal curettes may not adapt well to furcation concavities; sickle scalers are for
supragingival use; ultrasonic standard tips lack furcation-specific design.
Question 4
A 32-year-old patient reports bleeding gums during brushing. Clinical exam reveals generalized erythema,
edema, and BOP at 40% of sites. There is no attachment loss or suppuration. What is the most likely diagnosis?
A. Localized aggressive periodontitis
B. Gingivitis associated with dental biofilm
C. Necrotizing ulcerative gingivitis
D. Chronic periodontitis Stage I
🟢B
🔴 RATIONALE: Gingivitis is inflammation confined to gingiva without attachment loss. Bleeding, erythema,
edema, and BOP without clinical attachment loss or suppuration meet diagnostic criteria. Necrotizing disease
PLUS RATIONALES 2026 Q&A | INSTANT DOWNLOAD PDF.
Core Domains
1. Patient Assessment and Dental Hygiene Diagnosis
2. Preventive and Therapeutic Oral Care
3. Periodontal and Hard Tissue Evaluation
4. Radiography and Diagnostic Imaging
5. Pharmacology and Pain Management
6. Legal, Ethical, and Regulatory Standards (IL State Specific)
7. Infection Control and Safety Protocols
8. Community Oral Health and Patient Education
Introduction
This examination is designed to evaluate the foundational and applied competencies required for licensure as a
dental hygienist in Illinois. It assesses knowledge in patient assessment, clinical procedures, radiography,
periodontics, pharmacology, infection control, and state-specific legal and ethical standards. Questions include
,multiple-choice and scenario-based items that emphasize real-world clinical decision-making, critical thinking,
and adherence to professional regulations. Successful candidates demonstrate the ability to integrate theory with
practical application, ensuring safe, effective, and patient-centered care across diverse populations and settings.
SECTION ONE: QUESTIONS 1–100
Question 1
A 45-year-old patient with a history of hypertension controlled with lisinopril presents for a prophylaxis. Which
finding requires immediate medical consultation before proceeding?
A. Blood pressure 118/76 mmHg
B. Dry hacking cough for six weeks
C. Gingival enlargement in mandibular anterior area
D. Heart rate 88 bpm
🟢B
🔴 RATIONALE: Lisinopril (an ACE inhibitor) commonly causes a persistent dry cough. While not life-
threatening, the cough should be evaluated to rule out other causes or medication change. The gingival
enlargement is more consistent with nifedipine or phenytoin, not lisinopril. BP and heart rate are normal.
,Question 2
According to the Illinois Dental Practice Act, a dental hygienist may perform local infiltration anesthesia under
which condition?
A. Without any supervision after passing the clinical exam
B. Only with a dentist physically present in the operatory
C. Under general supervision with prior written authorization
D. Only after completing a board-approved nitrous oxide course
🟢C
🔴 RATIONALE: Illinois law permits dental hygienists to administer local infiltration anesthesia under general
supervision if the dentist has given prior written authorization and the hygienist has completed accredited
training. Physical presence is not required for infiltration.
Question 3
Which of the following is the MOST appropriate for removing tenacious calculus from a moderate furcation
involvement on a mandibular first molar?
A. Universal curette
B. Periodontal file
, C. Sickle scaler
D. Ultrasonic scaler with a standard tip
🟢B
🔴 RATIONALE: Periodontal files are specifically designed to crush and remove tenacious calculus in furcations
and deep pockets. Universal curettes may not adapt well to furcation concavities; sickle scalers are for
supragingival use; ultrasonic standard tips lack furcation-specific design.
Question 4
A 32-year-old patient reports bleeding gums during brushing. Clinical exam reveals generalized erythema,
edema, and BOP at 40% of sites. There is no attachment loss or suppuration. What is the most likely diagnosis?
A. Localized aggressive periodontitis
B. Gingivitis associated with dental biofilm
C. Necrotizing ulcerative gingivitis
D. Chronic periodontitis Stage I
🟢B
🔴 RATIONALE: Gingivitis is inflammation confined to gingiva without attachment loss. Bleeding, erythema,
edema, and BOP without clinical attachment loss or suppuration meet diagnostic criteria. Necrotizing disease
