When overlapped contacts appear on film, what is the most likely cause?

Overlapped contacts appear on a dental radiograph when the horizontal angulation is incorrect. This condition occurs when the X-ray beam is not directed parallel to the interproximal surfaces of adjacent teeth, leading to an overlap where one tooth obscures another. Proper horizontal angulation allows for the clear distinction of adjacent teeth, ensuring that the contacts are well visualized and not superimposed on one another.

This technique is crucial because accurate horizontal angulation helps obtain the true anatomical relationship between teeth, allowing for a more precise diagnosis and effective treatment planning. When the angulation is not correct, overlapping can occur, leading to potential misinterpretation of dental structures.