Figure 2: The relationships between tooth block, CCD, pink wax, and x-ray tube for taking bitewing radiograph. A 14 millimeters thick pink wax, cover the whole detector surface, was placed between the tooth block and x-ray tube to mimic the tooth-soft tissue relationship. A 12-inch source-to-object distance was used with the angle between x-ray beam and teeth long axis of 8 degrees.