**Core Concept**
Enamel infarctions refer to localized areas of enamel necrosis, which can occur due to inadequate blood supply or other factors affecting the enamel organ during tooth development. These lesions are a type of enamel defect that can be detected through various diagnostic methods.

**Why the Correct Answer is Right**
Enamel infarctions can be detected by **transillumination**, a diagnostic technique that involves shining a light through the tooth to identify areas of enamel opacification or discoloration. This method is particularly useful for detecting enamel infarctions, as it can highlight the characteristic changes in enamel density associated with these lesions. Transillumination works by exploiting the differences in light transmission through the tooth, allowing clinicians to visualize areas of enamel infarction.

**Why Each Wrong Option is Incorrect**
**Option A:** Radiography, while useful for detecting a range of dental abnormalities, is not the best method for detecting enamel infarctions specifically. This is because radiographs primarily provide information on tooth structure and density, rather than the subtle changes in enamel texture associated with infarctions.
**Option B:** Clinical examination, while essential for identifying many dental problems, is not sufficient for detecting enamel infarctions. These lesions are often subtle and may not be visible to the naked eye, making transillumination a more effective diagnostic tool.
**Option C:** Microscopic examination, while useful for studying enamel structure at the cellular level, is not a practical method for detecting enamel infarctions in clinical practice. Transillumination is a more efficient and effective way to identify these lesions in a clinical setting.

**Clinical Pearl / High-Yield Fact**
A key point to remember when considering enamel infarctions is that they are often associated with other enamel defects, such as enamel hypoplasia or hypocalcification. Clinicians should be aware of this correlation and consider it when evaluating patients with enamel infarctions.

**Correct Answer: D. Transillumination**