Commission on Dental Competency Assessments (CDCA) Overview
These study notes are designed to help candidates prepare for the CDCA (ADEX) dental hygiene clinical examination. The notes cover six core subjects based on the Dental Conquer curriculum, focusing on entry-to-practice competencies. Candidates should use these notes alongside official ADEX manuals and forms. All pass marks, formats, and eligibility details should be verified with the official CDCA/ADEX website.
For Dental Conquer practice planning, this module is tracked as 80 questions over about 120 minutes with a listed pass mark of 70%. Treat those numbers as practice baselines and verify the current official format before scheduling.
How This Guide Is Organized
The sections below turn the syllabus into studyable subject blocks. Read a subject first, explain the must-know ideas without notes, then use questions and flashcards to test whether the knowledge holds under pressure.
- Medical and Dental History Evaluation
- Intraoral and Extraoral Examination
- Radiographic Interpretation and Safety
- Periodontal Assessment and Treatment Planning
- Applied Pharmacology and Pain Management
- Professional Ethics and Infection Control
Exam Snapshot and Readiness Target
Format: Clinical skills assessment (OSCE/CSCE) and patient-based examinations; written component may be included. Practice baseline: 80 questions, 120 minutes, 70% pass mark.
Candidate level: Entry-to-practice dental hygiene licensure
Readiness target: Competent in clinical decision-making, patient assessment, radiography, periodontics, pharmacology, ethics, and infection control.
Most candidates should budget at least 38+ focused study hours, then adjust upward for unfamiliar clinical systems, regulatory content, or specialty-level case reasoning.
Medical and Dental History Evaluation
Syllabus Focus
- Systematic review of medical history
- Dental history and chief complaint
- Vital signs and risk assessment
- Medical consultations and modifications
Key Notes
- Always obtain and document a comprehensive medical history including medications, allergies, and systemic conditions.
- Use a standardized form; verify with patient interview.
- Assess ASA classification to determine treatment modifications.
- Identify conditions requiring antibiotic prophylaxis (e.g., joint replacements, certain cardiac conditions) per current AHA/AAOS guidelines.
- Record vital signs: blood pressure, pulse, respiration; note any abnormalities.
- Evaluate need for medical consultation before proceeding with treatment.
- Document all findings and any modifications to treatment plan.
Must Know
- ASA classification system (I-IV) and implications for dental hygiene care.
- Common medications affecting dental treatment: anticoagulants, bisphosphonates, immunosuppressants.
- Indications for antibiotic prophylaxis: prosthetic joints, history of infective endocarditis, certain congenital heart defects.
- Signs of undiagnosed medical conditions: hypertension, diabetes, thyroid disorders.
Clinical and Exam Application
- When a patient reports a heart murmur, determine if prophylaxis is needed based on current guidelines.
- For a patient on warfarin, check INR before scaling; consult physician if INR > 3.5.
- If patient has a history of radiation to head/neck, assess for xerostomia and risk of osteoradionecrosis.
High-Yield Distinctions
- ASA II vs. III: ASA II has mild systemic disease (e.g., controlled hypertension); ASA III has severe disease that limits activity (e.g., COPD).
- Antibiotic prophylaxis is not recommended for most dental procedures in patients with prosthetic joints unless high-risk (e.g., immunocompromised).
- Bisphosphonate-related osteonecrosis of the jaw (BRONJ) risk: higher with IV bisphosphonates; avoid invasive surgery if possible.
Common Pitfalls
- Failing to update medical history at each appointment.
- Not recognizing that a patient's 'allergy to penicillin' may be a non-allergic reaction.
- Assuming a patient's medication list is complete without asking about over-the-counter and herbal supplements.
Review Tasks
- Review ASA classification and practice assigning ASA status to sample cases.
- Memorize current antibiotic prophylaxis regimens (amoxicillin 2g, etc.).
- Practice taking and interpreting vital signs.
Intraoral and Extraoral Examination
Syllabus Focus
- Extraoral examination: head, neck, lymph nodes, TMJ
- Intraoral examination: soft tissues, hard tissues, occlusion
- Oral cancer screening
- Documentation of findings
Key Notes
- Perform extraoral exam systematically: inspect and palpate lymph nodes, thyroid, salivary glands, TMJ.
- Intraoral exam: inspect lips, buccal mucosa, tongue, floor of mouth, palate, gingiva, teeth.
- Use a systematic approach (e.g., from posterior to anterior) to avoid missing lesions.
- Oral cancer screening: look for red/white lesions, ulcerations, masses; palpate for induration.
- Document all findings using correct terminology (e.g., 'erythroplakia', 'leukoplakia').
- Assess occlusion: Angle classification, overjet, overbite, crossbite, open bite.
- Note any restorations, caries, fractures, wear, and existing dental work.
Must Know
- Normal vs. abnormal lymph node characteristics: mobile, firm, non-tender vs. fixed, hard, tender.
- Common oral lesions: aphthous ulcers, herpes labialis, lichen planus, candidiasis.
- TMJ assessment: palpation for tenderness, crepitus, deviation on opening.
- Angle classification of occlusion: Class I (normal), Class II (retrognathic), Class III (prognathic).
Clinical and Exam Application
- If a patient has a non-healing ulcer on the lateral tongue for >2 weeks, refer for biopsy to rule out squamous cell carcinoma.
- When palpating lymph nodes, note if submandibular nodes are enlarged and tender (infection) vs. firm and fixed (malignancy).
- Assess for signs of bruxism: wear facets, masseter hypertrophy, linea alba.
High-Yield Distinctions
- Leukoplakia vs. erythroplakia: leukoplakia is a white patch that cannot be rubbed off; erythroplakia is a red patch with higher malignant potential.
- Herpes labialis (cold sore) vs. aphthous ulcer: herpes is vesicular, contagious, on keratinized tissue; aphthous is ulcerative, non-contagious, on non-keratinized mucosa.
- Lichen planus: reticular (white lacy lines) vs. erosive (painful, ulcerative); erosive form may require corticosteroid treatment.
Common Pitfalls
- Missing lesions in the floor of mouth or retromolar area due to poor visualization.
- Confusing a torus mandibularis with a pathological lesion.
- Not documenting the size, color, and location of lesions.
Review Tasks
- Practice extraoral and intraoral exam on a partner or mannequin.
- Review images of common oral lesions and their characteristics.
- Study TMJ disorders and their clinical signs.
Radiographic Interpretation and Safety
Syllabus Focus
- Radiographic techniques (bitewing, periapical, panoramic)
- Radiation safety and ALARA principle
- Normal radiographic anatomy
- Interpretation of caries, periodontal disease, and pathology
Key Notes
- Use the ALARA principle: As Low As Reasonably Achievable. Minimize exposure through proper technique, collimation, and shielding.
- Bitewings are best for detecting interproximal caries and assessing crestal bone levels.
- Periapical radiographs show the entire tooth and surrounding bone; useful for periapical pathology.
- Panoramic radiographs provide an overview but have lower resolution; useful for impacted teeth, large lesions, and growth assessment.
- Normal anatomy: lamina dura, periodontal ligament space, trabecular bone, maxillary sinus, mandibular canal.
- Caries appear as radiolucent areas; location (enamel, dentin, pulp) determines severity.
- Periodontal disease: bone loss is measured from CEJ to crestal bone; furcation involvement, vertical defects.
Must Know
- Radiation safety: use lead apron and thyroid collar, proper film/sensor placement, avoid retakes.
- Identify normal anatomical landmarks: mental foramen, incisive foramen, maxillary sinus, nasal septum, zygomatic arch.
- Recognize common pathologies: periapical radiolucency (abscess/granuloma), radiopaque lesions (condensing osteitis, tori).
- Bone loss classification: horizontal vs. vertical; mild (<2mm), moderate (2-4mm), severe (>4mm).
Clinical and Exam Application
- When a patient presents with a deep carious lesion on a bitewing, take a periapical to assess periapical status.
- If panoramic shows a radiopacity in the mandible, consider differentials: tori, sialolith, osteoma, or idiopathic osteosclerosis.
- For periodontal assessment, use vertical bitewings to better visualize crestal bone and furcations.
High-Yield Distinctions
- Radiolucent vs. radiopaque: radiolucent (dark) = less dense (caries, cyst, abscess); radiopaque (white) = more dense (bone, calculus, restoration).
- Periapical granuloma vs. cyst: both appear as radiolucency; cyst has a corticated border, granuloma does not.
- External vs. internal resorption: external resorption has irregular outline; internal resorption is smooth and symmetrical within the pulp chamber.
Common Pitfalls
- Overlapping contacts on bitewings due to incorrect horizontal angulation.
- Misinterpreting the mental foramen as a periapical lesion.
- Failing to recognize a retained root tip on a panoramic radiograph.
Review Tasks
- Practice mounting and interpreting full-mouth series.
- Review normal radiographic anatomy with labeled diagrams.
- Study common radiographic artifacts and how to avoid them.
Periodontal Assessment and Treatment Planning
Syllabus Focus
- Periodontal probing and charting
- Classification of periodontal diseases
- Treatment planning: non-surgical and surgical
- Maintenance and recall intervals
Key Notes
- Use a periodontal probe with standardized pressure (20-25g). Record probing depths, bleeding on probing, recession, furcation involvement, mobility.
- Periodontal disease classification: gingivitis (no attachment loss) vs. periodontitis (attachment loss).
- Staging and grading of periodontitis: Stage I-IV based on severity and complexity; Grade A-C based on progression rate.
- Non-surgical therapy: scaling and root planing (SRP), adjunctive antimicrobials (local or systemic).
- Surgical therapy: flap surgery, osseous surgery, regenerative procedures.
- Maintenance: recall intervals based on risk assessment (3-6 months).
- Risk factors: smoking, diabetes, poor oral hygiene, genetic factors.
Must Know
- Normal probing depth: 1-3mm; bleeding on probing indicates inflammation.
- Furcation involvement: Class I (probe enters <3mm), Class II (probe enters >3mm but not through), Class III (through-and-through).
- Mobility: Class I (slight), Class II (moderate, up to 1mm), Class III (severe, >1mm or vertical).
- Indications for SRP: probing depths ≥4mm with bleeding, or ≥5mm regardless of bleeding.
Clinical and Exam Application
- For a patient with generalized Stage III Grade B periodontitis, plan full-mouth SRP with 2-4 appointments, consider local antibiotic delivery (e.g., Arestin) in deep pockets.
- If a patient has a 6mm pocket on a molar with Class II furcation, refer for possible surgical intervention after initial SRP.
- For a smoker with periodontitis, emphasize smoking cessation and schedule more frequent maintenance (every 3 months).
High-Yield Distinctions
- Gingivitis vs. periodontitis: gingivitis is reversible with no attachment loss; periodontitis involves irreversible attachment loss.
- Chronic vs. aggressive periodontitis: chronic is slow progression, usually in adults; aggressive is rapid, often in younger patients with familial pattern.
- Necrotizing periodontal diseases: NUG (necrotizing ulcerative gingivitis) vs. NUP (necrotizing ulcerative periodontitis); associated with stress, smoking, immunosuppression.
Common Pitfalls
- Probing too forcefully, causing pain and inaccurate readings.
- Not recording recession, which underestimates attachment loss.
- Assuming all 4mm pockets require SRP; consider bleeding on probing and risk factors.
Review Tasks
- Practice probing on a typodont or partner, ensuring correct technique.
- Review the 2017 AAP/EFP classification of periodontal diseases.
- Create treatment plans for sample cases with varying severity.
Applied Pharmacology and Pain Management
Syllabus Focus
- Local anesthetics: types, dosages, maximum doses
- Analgesics: NSAIDs, acetaminophen, opioids
- Antimicrobials: antibiotics, antifungals, antivirals
- Medical emergencies and drug interactions
Key Notes
- Local anesthetics: amides (lidocaine, articaine, mepivacaine, bupivacaine) vs. esters (procaine, benzocaine). Amides are most common; metabolized in liver.
- Maximum doses: lidocaine 2% with epinephrine 1:100,000 = 7.2 mg/kg, max 500 mg; articaine 4% with epinephrine = 7 mg/kg, max 500 mg.
- Vasoconstrictors: epinephrine prolongs anesthesia and reduces bleeding; contraindicated in severe cardiovascular disease (e.g., unstable angina, recent MI).
- Analgesics: NSAIDs (ibuprofen, naproxen) are first-line for dental pain; acetaminophen for mild pain or when NSAIDs contraindicated; opioids reserved for severe pain.
- Antibiotics: amoxicillin is first-line for odontogenic infections; clindamycin for penicillin allergy.
- Medical emergencies: epinephrine for anaphylaxis, nitroglycerin for angina, oxygen for hypoxia, glucose for hypoglycemia.
Must Know
- Calculate maximum dose of local anesthetic based on patient weight and medical history.
- Recognize signs of local anesthetic overdose: CNS (tinnitus, metallic taste, seizures) and cardiovascular (hypotension, arrhythmias).
- Drug interactions: NSAIDs with anticoagulants increase bleeding risk; epinephrine with non-selective beta-blockers can cause hypertensive crisis.
- Antibiotic prophylaxis regimens for dental procedures: amoxicillin 2g PO 1 hour before procedure; if allergic, clindamycin 600mg PO.
Clinical and Exam Application
- For a patient with a history of MI 6 months ago, use local anesthetic with epinephrine cautiously (max 0.036 mg epinephrine per appointment).
- If a patient is on warfarin with INR 2.5, avoid NSAIDs; use acetaminophen for pain.
- For a patient with penicillin allergy and a severe odontogenic infection, prescribe clindamycin 300mg QID for 7 days.
High-Yield Distinctions
- Amide vs. ester: amides have lower allergy risk; esters are metabolized by plasma pseudocholinesterase and may cause allergic reactions in patients allergic to PABA.
- Lidocaine vs. articaine: articaine has higher lipid solubility and better bone penetration; max dose similar.
- Ibuprofen vs. acetaminophen: ibuprofen has anti-inflammatory effect; acetaminophen is antipyretic and analgesic but not anti-inflammatory.
Common Pitfalls
- Exceeding maximum dose of local anesthetic, especially in children or small adults.
- Not considering drug interactions with herbal supplements (e.g., ginkgo biloba with anticoagulants).
- Prescribing antibiotics for viral infections or non-infectious conditions.
Review Tasks
- Memorize maximum doses for common local anesthetics.
- Review medical emergency protocols and drug kit contents.
- Practice calculating doses for pediatric patients.
Professional Ethics and Infection Control
Syllabus Focus
- Ethical principles: autonomy, beneficence, nonmaleficence, justice
- Informed consent and patient rights
- Infection control standards: OSHA, CDC, ADA
- Sterilization and disinfection protocols
Key Notes
- Four core ethical principles: autonomy (respect patient's decisions), beneficence (do good), nonmaleficence (do no harm), justice (fairness).
- Informed consent: explain diagnosis, treatment options, risks, benefits, alternatives; obtain written consent.
- Patient rights: confidentiality (HIPAA), right to refuse treatment, access to records.
- Infection control: standard precautions (gloves, mask, eyewear, gown) for all patients.
- Hand hygiene: wash with soap and water or use alcohol-based hand rub before and after patient contact.
- Sterilization: autoclave (steam under pressure) for heat-stable instruments; monitor with biological indicators weekly.
- Disinfection: intermediate-level disinfectants (e.g., EPA-registered hospital disinfectant) for clinical surfaces.
Must Know
- OSHA Bloodborne Pathogens Standard: requires exposure control plan, hepatitis B vaccination, personal protective equipment (PPE), and post-exposure follow-up.
- CDC Guidelines for Infection Control in Dental Settings: categorize instruments as critical (penetrate soft tissue/bone), semicritical (contact mucous membranes), noncritical (contact intact skin).
- Ethical obligations: report suspected abuse/neglect, maintain competence, avoid discrimination.
- HIPAA: protect patient health information; obtain authorization for disclosure except for treatment, payment, or operations.
Clinical and Exam Application
- When a patient refuses radiographs, respect autonomy but document informed refusal and explain risks.
- If a needlestick injury occurs, immediately wash wound, report to supervisor, and follow post-exposure prophylaxis protocol.
- For a patient with active tuberculosis, defer elective treatment and refer for medical evaluation; use airborne precautions if urgent care needed.
High-Yield Distinctions
- Critical vs. semicritical vs. noncritical instruments: critical (e.g., scalers, surgical instruments) must be sterilized; semicritical (e.g., mouth mirrors) must be sterilized or high-level disinfected; noncritical (e.g., x-ray head) can be intermediate-level disinfected.
- Autoclave vs. chemical vapor vs. dry heat: autoclave is most common; chemical vapor (chemiclave) is faster but requires special solution; dry heat is for instruments that may rust.
- Ethical dilemma: patient wants treatment that is not clinically indicated; balance autonomy with nonmaleficence (do no harm) and beneficence (provide appropriate care).
Common Pitfalls
- Reusing single-use items (e.g., prophylaxis angles, saliva ejectors).
- Not changing gloves between patients or after touching contaminated surfaces.
- Failing to document informed consent properly.
Review Tasks
- Review OSHA and CDC guidelines for infection control.
- Practice ethical decision-making using case scenarios.
- Study sterilization monitoring methods (biological, chemical, mechanical indicators).
How To Use These Notes With Practice Questions
Do not jump straight from reading to a full mock. Work by subject first: review the key notes, make a short recall sheet from memory, then answer a focused question set. After each miss, decide whether the problem was missing knowledge, poor clinical sequencing, weak source-rule recall, or a distractor you failed to eliminate.
Dental Conquer's question bank, flashcards, mind maps, and spaced review tools are most useful after this instruction layer because they reveal which parts of the notes are not yet retrievable.
Final Review Checklist
- Review all six subjects systematically, focusing on must-know items and high-yield distinctions.
- Practice clinical reasoning with case scenarios that integrate multiple subjects (e.g., a patient with diabetes and periodontitis).
- Verify all exam-specific details (format, pass mark, eligibility) on the official CDCA/ADEX website.
- Use official ADEX manuals and forms for hands-on practice.
- Take practice exams under timed conditions to build speed and accuracy.
Official Sources and Further Reading
Use these sources as the final authority for format, eligibility, rules, and exam updates. Study notes are a preparation layer, not a replacement for official candidate guidance.