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Radiographic Film Processing — NDEB AFK MCQ

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HardRadiology & ImagingRadiographic Film ProcessingNDEB AFK

What is the role of the reducing agent (sodium sulfite or sodium thiosulfate) in the dental X-ray film developing process?

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Correct answer: DTo prevent oxidation of the developer solution

In the manual developing process, the reducing agent (developing agents such as hydroquinone and elon/metol) converts exposed silver halide crystals to metallic silver (creating the visible image). The sodium sulfite (preservative) prevents oxidation of the developing agents and extends the solution's shelf life. This is distinct from the reducer's role. The fixer (hypo/sodium thiosulfate) removes unexposed silver halide crystals. The hardener (potassium alum) hardens the gelatin.

Reference: White & Pharoah – Oral Radiology: Principles and Interpretation, 8th ed., 2019