Dentistry: Oral Diagnosis and Safe Dental Management
The Dentistry domain of the MDCN Assessment tests foreign-trained dentists on Nigerian-standard oral diagnosis, treatment planning, infection control, and recognition of red flags. Vignettes commonly ask for the next best step in a patient with toothache, swelling, bleeding gums, or an oral ulcer.
Core rules
- Take a focused history: pain (site, character, duration, triggers, radiation), swelling, bleeding, trauma, and relevant medical history including diabetes, hypertension, bleeding disorders, pregnancy, bisphosphonate use, and anticoagulants.
- Examine extraorally for facial swelling, lymphadenopathy, and temporomandibular joint function; intraorally for caries, periodontal pockets, mucosal lesions, and occlusion.
- Common conditions include dental caries, reversible and irreversible pulpitis, apical periodontitis, periodontal disease, oral candidiasis, recurrent aphthous ulcers, oral squamous cell carcinoma, dental trauma, and impacted third molars.
- Prescribe antibiotics only when there is systemic involvement or spreading infection; they are adjuncts to drainage, not substitutes. Avoid tetracyclines in pregnancy and children under 8; use caution with NSAIDs in asthma, renal disease, and peptic ulcer.
- Refer urgently any non-healing oral ulcer longer than 2 weeks, induration, or unexplained lymphadenopathy to rule out oral cancer.
Worked example
A 45-year-old woman has a painful lower molar with buccal swelling, fever, and difficulty swallowing. Reasoning: this suggests a spreading odontogenic infection with systemic signs. Do not simply prescribe antibiotics and send her home. Assess the airway, arrange urgent drainage by incision or extraction as appropriate, start antibiotics, and refer if there is trismus or submandibular involvement. An isolated toothache without swelling may need pulp therapy or extraction, not antibiotics.
Traps that cost marks
Prescribing antibiotics for uncomplicated pulpitis; missing oral cancer; extracting a tooth in a patient on warfarin without checking INR; ignoring bisphosphonate history and the risk of osteonecrosis; failing to ask about allergies, especially penicillin.