What does it imply if a film appears black after processing?

When a film appears black after processing, this typically indicates that it was exposed to light before the developing process. In photography, especially in dental radiography, films are sensitive to light, and if they are inadvertently exposed to it—whether before, during, or after exposure—the resulting image will be completely dark. This is due to the silver halide crystals in the film being fully developed in the presence of light, resulting in a dense black area where the film has been overexposed.

Other options would not lead to the film appearing completely black. For instance, if the film were underexposed, it would show up as light or blank rather than black. Proper exposure would yield a diagnostic image, and development time affects contrast and density but not exclusively to the extent of making the film appear entirely black, unless it was overdeveloped to an extreme degree. Thus, understanding the implications of exposure and development processes is crucial in dental assisting and radiography.