Systems for grading approximal carious lesions and overlaps diagnosed from bitewing radiographs. Proposals for future standardization.

The diagnosis of dental caries from bitewing radiographs has become an important and integral part of many clinical caries trials, particularly in longitudinal studies. Although many seemingly similar systems for grading the degrees of approximal lesions have been used, the diagnostic criteria employed often differ in a number of significant areas. A variety of different conventions have evolved for the treatment of: 1) overlapping surfaces, 2) lesions in the region of the ADJ, 3) subdivision of the radiographic enamel cap and 4) score transitions and caries progression systems. Direct intertrial comparisons may be invalidated by the use of incompatible grading systems. Whilst one rigid grading system will not be suitable for all clinical trials, the use of the appropriate scoring codes and criteria from a standard system may greatly facilitate the comparison and interpretation of results. A comprehensive standard system for the grading and scoring of radiographic diagnoses (compatible with the existing WHO recommendations for the grading of clinically diagnosed lesions) is proposed.