NBDHE (National Board Dental Hygiene
Examination) – Comprehensive Study Guide
& Practice Exam
The National Board Dental Hygiene Examination (NBDHE) is a standardized
written exam that assesses a candidate's knowledge of biomedical and
dental hygiene sciences and their ability to apply this information in a
problem-solving context. It is administered by the Joint Commission on
National Dental Examinations (JCNDE) and is a key requirement for dental
hygiene licensure in most states.
This section tests knowledge across three major content areas:
1. Scientific Basis for Dental Hygiene Practice: Includes anatomy,
physiology, biochemistry, microbiology, pathology, and
pharmacology.
2. Provision of Clinical Dental Hygiene Services: Covers patient
assessment, radiograph interpretation, care planning, periodontal
procedures, and professional responsibility.
3. Community Health/Research Principles: Focuses on health
promotion, disease prevention in populations, and research
methodology.
Component B: Case-Based Clinical Application
This component presents 12-15 patient cases, each requiring you to
integrate knowledge from Component A to answer questions about
assessment, diagnosis, planning, and treatment. You might see patient
charts, radiographs, or photographs as part of the case presentations.
Q1. A patient's dental chart notes generalized bone loss of 3-5mm.
What is the most likely diagnosis?
• A) Gingivitis
• B) Periodontitis
, • C) Pulpitis
• D) Pericoronitis
Answer: B – Periodontitis is a serious gum infection that damages the soft
tissue and, without treatment, can destroy the bone that supports your
teeth. Gingivitis is a milder, reversible form of gum disease that only affects
the gums. Periodontitis is characterized by irreversible loss of attachment
and bone.
Q2. Which of the following drugs is the most commonly used for local
anesthesia during dental procedures?
• A) Lidocaine
• B) Penicillin
• C) Acetaminophen
• D) Nitrous Oxide
Answer: A – Lidocaine is a widely used local anesthetic that works by
blocking sodium channels in nerve cells, preventing the transmission of
pain signals.
Q3. The primary cause of dental caries is:
• A) Acid produced by bacteria
• B) Sugar intake
• C) Plaque accumulation
• D) A combination of factors
Answer: D – Dental caries is a complex, multifactorial disease caused by
the interplay of cariogenic bacteria (like S. mutans), fermentable
carbohydrates (sugars), a susceptible tooth surface, and time.
, Q4. A 58-year-old patient with a history of type 2 diabetes mellitus and
severe periodontitis is seeking periodontal therapy. What is the most
important consideration before initiating treatment?
• A) Consultation with a physician regarding glycemic control
• B) Using a new type of ultrasonic scaler
• C) Prescribing a high dose of antibiotics
• D) Performing gingivectomy on all quadrants
Answer: A – Poor glycemic control can significantly impair wound healing
and increase the risk of infection. Consultation with the patient's physician
is crucial to ensure their blood sugar levels are stable before any invasive
periodontal treatment.
Q5. The process of removing dental plaque and calculus from tooth
surfaces is known as:
• A) Prophylaxis
• B) Scaling and Root Planing
• C) Curettage
• D) All of the above
Answer: D – Prophylaxis is a general term for preventive dental cleaning.
Scaling and root planing is a non-surgical procedure that involves removing
plaque and calculus from the crown and root surfaces. Curettage is the
removal of diseased soft tissue lining the periodontal pocket.
Q6. In a radiographic image of the maxillary anterior teeth, which
anatomical landmark appears as a radiolucent (dark) area above the
incisors?
• A) Maxillary Sinus
• B) Incisive Foramen
Examination) – Comprehensive Study Guide
& Practice Exam
The National Board Dental Hygiene Examination (NBDHE) is a standardized
written exam that assesses a candidate's knowledge of biomedical and
dental hygiene sciences and their ability to apply this information in a
problem-solving context. It is administered by the Joint Commission on
National Dental Examinations (JCNDE) and is a key requirement for dental
hygiene licensure in most states.
This section tests knowledge across three major content areas:
1. Scientific Basis for Dental Hygiene Practice: Includes anatomy,
physiology, biochemistry, microbiology, pathology, and
pharmacology.
2. Provision of Clinical Dental Hygiene Services: Covers patient
assessment, radiograph interpretation, care planning, periodontal
procedures, and professional responsibility.
3. Community Health/Research Principles: Focuses on health
promotion, disease prevention in populations, and research
methodology.
Component B: Case-Based Clinical Application
This component presents 12-15 patient cases, each requiring you to
integrate knowledge from Component A to answer questions about
assessment, diagnosis, planning, and treatment. You might see patient
charts, radiographs, or photographs as part of the case presentations.
Q1. A patient's dental chart notes generalized bone loss of 3-5mm.
What is the most likely diagnosis?
• A) Gingivitis
• B) Periodontitis
, • C) Pulpitis
• D) Pericoronitis
Answer: B – Periodontitis is a serious gum infection that damages the soft
tissue and, without treatment, can destroy the bone that supports your
teeth. Gingivitis is a milder, reversible form of gum disease that only affects
the gums. Periodontitis is characterized by irreversible loss of attachment
and bone.
Q2. Which of the following drugs is the most commonly used for local
anesthesia during dental procedures?
• A) Lidocaine
• B) Penicillin
• C) Acetaminophen
• D) Nitrous Oxide
Answer: A – Lidocaine is a widely used local anesthetic that works by
blocking sodium channels in nerve cells, preventing the transmission of
pain signals.
Q3. The primary cause of dental caries is:
• A) Acid produced by bacteria
• B) Sugar intake
• C) Plaque accumulation
• D) A combination of factors
Answer: D – Dental caries is a complex, multifactorial disease caused by
the interplay of cariogenic bacteria (like S. mutans), fermentable
carbohydrates (sugars), a susceptible tooth surface, and time.
, Q4. A 58-year-old patient with a history of type 2 diabetes mellitus and
severe periodontitis is seeking periodontal therapy. What is the most
important consideration before initiating treatment?
• A) Consultation with a physician regarding glycemic control
• B) Using a new type of ultrasonic scaler
• C) Prescribing a high dose of antibiotics
• D) Performing gingivectomy on all quadrants
Answer: A – Poor glycemic control can significantly impair wound healing
and increase the risk of infection. Consultation with the patient's physician
is crucial to ensure their blood sugar levels are stable before any invasive
periodontal treatment.
Q5. The process of removing dental plaque and calculus from tooth
surfaces is known as:
• A) Prophylaxis
• B) Scaling and Root Planing
• C) Curettage
• D) All of the above
Answer: D – Prophylaxis is a general term for preventive dental cleaning.
Scaling and root planing is a non-surgical procedure that involves removing
plaque and calculus from the crown and root surfaces. Curettage is the
removal of diseased soft tissue lining the periodontal pocket.
Q6. In a radiographic image of the maxillary anterior teeth, which
anatomical landmark appears as a radiolucent (dark) area above the
incisors?
• A) Maxillary Sinus
• B) Incisive Foramen
