Dental OSCE (Objective Structured Clinical Examination) Practice Exam

What is the likely cause of dark stains on teeth?

1. Fluoride overexposure

2. Coffee consumption

3. Tetracycline

4. Smoking

The correct answer is: Tetracycline

Dark stains on teeth can have various causes, each linked to specific substances or habits that impact dental aesthetics. The choice of tetracycline as the likely cause is particularly significant due to its well-documented association with intrinsic staining. Tetracycline is an antibiotic that, when taken during the time of tooth development—especially in children—can lead to a grey or brown discoloration. This arises because the drug can bind to calcium in the developing teeth, resulting in noticeable staining that is often permanent. While other factors can certainly contribute to tooth discoloration, such as diet and lifestyle choices, the staining from tetracycline is distinct in its origins and appears more uniformly across teeth. For example, coffee consumption can lead to extrinsic staining on the enamel, which is typically more superficial and can be managed with professional cleaning. Fluoride overexposure typically results in white spots or mottling rather than dark stains. Smoking predominantly leads to surface stains due to tar and nicotine, which again are not the same as what is induced by tetracycline. Understanding the relationship between certain medications and their side effects on dental health is crucial for diagnosis and management of tooth discoloration. This makes recognizing tetracycline as a cause of dark stains essential in clinical dentistry.