In spite of its shortcomings, bitewing radiography is an important aid particularly for approximal caries diagnosis. It also forms an important part in selecting individuals in need of extra preventive care and can be of help in restorative treatment decisions. For occlusal surfaces, the bitewing technique is important for detecting so-called hidden caries. Key ages for bitewing examinations are suggested to be 5, 8 to 9 and 12 to 14. Intervals between examinations should be based on individual risk assessment of new lesions or lesion progression. The proper time for restoring an approximal lesion in contact with its neighbour depends on a number of factors, among which the presence of frank cavitation is decisive.