Dictionary:

transillumination

  (trăns'ĭ-lū'mə-nā'shən, trănz'-)

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The passing of a light through the walls of a body part or organ to facilitate medical inspection.

1. examination of an organ, cavity, or tissue (for example, tooth or gingival tissue) by transmitted light. A valuable aid in detecting carious lesions, disclosing carious or demineralized dentin during cavity preparation, checking the finish or gingival margins of restorations, and revealing cement, debris, or calculus subgingivally. 2. a test in which the use of transmitted light may disclose a discoloration of the coronal aspect, indicating dentinal tubular hemorrhage as a result of trauma, pulpal necrosis, or fracture. 3. examination of tissues by means of a light placed so that the region under study is between the light source and the observer.

The illumination of a material from the rear by light which is transmitted through the material.

The passage of strong light through a body structure, to permit inspection by an observer on the opposite side.

• ocular t. — intense light placed on the sclera behind the ciliary body is transmitted to the interior of the eye, producing a tapetal reflex. Useful in identifying the presence of intraocular masses and demonstrating atrophy of the iris.