Hygiene Atlas

The atlas · 19 plates · 155 sub-topics

Topic atlas

The NBDHE tests three areas: the scientific basis of hygiene practice, clinical services, and community health and research. Each plate below is one board topic, with its sub-topics listed so you can see the whole syllabus at once.

Scientific Basis

Scientific Basis for Dental Hygiene Practice

61 items now → 56 after the Nov 2026 update

  1. Plate I

    Head and Neck Anatomy

    Bones, joints, muscles, nerves, vessels, lymph nodes and glands of the head and neck, with the clinical links a hygienist uses during the extraoral exam and local anesthesia.

    • Skull and facial bones
    • Temporomandibular joint
    • Muscles of mastication and expression
    • Cranial nerves
    • Blood supply and venous drainage
    • Lymph nodes
    • Salivary glands
    • Fascial spaces and spread of infection
    • Tongue and oral landmarks
  2. Plate II

    Dental Anatomy and Tooth Morphology

    Every permanent and primary tooth: crown and root form, numbering systems, eruption timing, occlusion and the root anatomy that decides how you instrument.

    • Tooth numbering systems
    • Eruption of the primary teeth
    • Eruption of the permanent teeth
    • Incisors
    • Canines
    • Premolars
    • Molars
    • Primary dentition
    • Occlusion
    • Developmental anomalies
  3. Plate III

    Histology and Embryology

    How teeth, the periodontium and the face develop, and the microscopic structure of enamel, dentin, cementum, pulp, PDL, bone and oral mucosa.

    • Cells and tissues
    • Tooth development
    • Enamel
    • Dentin and pulp
    • Cementum, PDL and alveolar bone
    • Gingiva and oral mucosa
    • Face and palate development
  4. Plate IV

    Physiology

    Normal body function that shows up chairside: vital signs, blood pressure, hemostasis, saliva, taste and the endocrine system.

    • Cardiovascular system and vital signs
    • Respiratory system
    • Endocrine system
    • Blood and hemostasis
    • Saliva
    • Nerve and muscle
    • Kidney and digestion
  5. Plate V

    Biochemistry and Nutrition

    Nutrients, vitamins and minerals, the diet-caries link, deficiency signs in the mouth and dietary counseling.

    • Biochemistry basics
    • Macronutrients
    • Vitamins
    • Minerals
    • Diet and caries
    • Eating disorders
  6. Plate VI

    Microbiology and Immunology

    Oral biofilm, periodontal and cariogenic bacteria, bloodborne and airborne diseases in the dental setting, and how the immune system responds.

    • Microbiology basics
    • Dental biofilm
    • Oral infections
    • Bloodborne diseases
    • Airborne diseases
    • Innate and adaptive immunity
    • Antibodies and hypersensitivity
    • Vaccines for health care personnel
  7. Plate VII

    General and Oral Pathology

    Inflammation and repair, oral lesions by appearance, cysts and tumors, oral cancer and the oral signs of systemic disease.

    • Inflammation and repair
    • Cell adaptation and neoplasia
    • White lesions
    • Red and pigmented lesions
    • Ulcers and vesicles
    • Soft-tissue masses
    • Cysts and odontogenic tumors
    • Oral cancer
    • Genetic and systemic conditions
  8. Plate VIII

    Pharmacology and Local Anesthesia

    Drug principles, the drug classes your patients take and their oral effects, antibiotic prophylaxis, local anesthetics, maximum doses and injection technique.

    • Drug principles
    • Prescriptions and controlled substances
    • Analgesics
    • Antibiotics
    • Antibiotic premedication
    • Cardiovascular drugs
    • CNS and other drugs
    • Local anesthetic agents
    • Local anesthetic doses
    • Vasoconstrictors
    • Injection techniques
    • Nitrous oxide sedation

Clinical Services

Provision of Clinical Dental Hygiene Services

115 items now → 124 after the Nov 2026 update

  1. Plate IX

    Dental Radiography

    X-ray production, receptors, paralleling and bisecting technique, panoramic imaging, technique errors, radiation safety and interpretation.

    • X-ray production
    • Radiation biology
    • Radiation protection
    • Selection criteria
    • Receptors and processing
    • Intraoral technique
    • Technique errors
    • Panoramic imaging
    • Normal radiographic anatomy
    • Interpretation
    • CBCT and emerging imaging
  2. Plate X

    Periodontology

    The periodontium in health and disease, the 2017 AAP/EFP staging and grading system, risk factors, nonsurgical therapy, implants and maintenance.

    • The periodontium
    • Etiology and pathogenesis
    • 2017 classification: staging and grading
    • Nonsurgical periodontal therapy
    • Chemotherapeutic agents
    • Surgical therapy
    • Implants and peri-implant disease
    • Occlusal trauma
  3. Plate XI

    Instrumentation

    The instrument library and how to use it: grasp, fulcrum, adaptation, angulation, probes, explorers, sickles, curettes, ultrasonics and sharpening.

    • Ergonomics and positioning
    • Instrument design
    • Grasp and fulcrum
    • Adaptation and angulation
    • Probes and explorers
    • Sickles and curettes
    • Files, hoes and chisels
    • Ultrasonic and piezo scalers
    • Sharpening
    • Polishing and air polishing
  4. Plate XII

    Patient Assessment and Charting

    Health history, vital signs, the extraoral and intraoral exam, hard- and soft-tissue charting, periodontal charting and the indices used on the boards.

    • Medical history and vital signs
    • Extraoral and intraoral exam
    • Periodontal charting
    • Hard-tissue charting
    • Indices
    • Care plan and DH diagnosis
  5. Plate XIII

    Medical Emergencies

    Preventing and managing office emergencies: syncope, hypoglycemia, angina and MI, anaphylaxis, asthma, seizures, stroke and CPR.

    • Prevention and the emergency kit
    • Syncope and hypotension
    • Cardiac emergencies
    • Respiratory emergencies
    • Diabetic emergencies
    • Allergy and anaphylaxis
    • Seizure and stroke
    • Other emergencies
    • Basic life support
  6. Plate XIV

    Infection Control

    Standard precautions, hand hygiene, PPE, instrument reprocessing, sterilization monitoring, waterlines, and exposure management under CDC and OSHA.

    • Standard precautions
    • Hand hygiene
    • Personal protective equipment
    • Sharps and exposure management
    • OSHA regulations
    • Spaulding classification
    • Sterilization
    • Sterilization monitoring
    • Surface disinfection
    • Waterlines and waste
  7. Plate XV

    Caries and Preventive Agents

    The caries process, risk assessment, fluorides and their concentrations, sealants, silver diamine fluoride and other remineralizing agents.

    • The caries process
    • Caries risk assessment
    • How fluoride works
    • Water fluoridation
    • Topical fluorides
    • Fluoride supplements
    • Fluoride toxicity
    • Pit and fissure sealants
    • SDF, xylitol and other agents
  8. Plate XVI

    Supportive Treatment Services

    Dental materials, selective polishing, impressions and study models, desensitization and whitening.

    • Restorative materials
    • Impressions and study models
    • Desensitization and whitening
    • Other supportive services
  9. Plate XVII

    Patient Management and Special Needs

    Patient education, behavior change, oral hygiene aids, tobacco cessation, anxiety and pain control, and care for medically compromised and special-needs patients.

    • Education and behavior change
    • Self-care aids
    • Tobacco cessation
    • Children and adolescents
    • Older adults
    • Medically compromised patients
    • Patients with disabilities
    • ASA classification
  10. Plate XVIII

    Ethics and Professional Responsibility

    The ADHA Code of Ethics, informed consent, records, HIPAA, supervision levels, negligence and mandated reporting.

    • Ethical principles
    • Consent and records
    • HIPAA and confidentiality
    • Law and liability
    • Licensure and practice acts
    • Reporting and the workplace

Community Health

Community Health and Research Principles

24 items now → 20 after the Nov 2026 update

  1. Plate XIX

    Community Health and Research

    Public health programs, levels of prevention, epidemiology, research design, the evidence hierarchy and the biostatistics behind community testlets.

    • Public health core functions
    • Access and financing
    • Epidemiology
    • Research design
    • Biostatistics
    • Community programs