Comparison between Panoramic Radiographic Techniques

A combination of Status-X (S-X) technique with high resolution single screens in vacuum-sealed cassettes, Orthopantomograph, Model OP 3 (OP3), with stationary anode and original screens as well as bite wings (BW), used on 21 patients, was evaluated regarding the depiction of the marginal bone support. The level of the alveolar bone margin was assessed by two methods, in tenths of the root length with a ruler and in tenths of millimetres with a caliper. Different image defects leading to uninterpretability were analysed. The frequency of uninterpretable bone supports as assessed with a ruler was 31% for S-X and 26% for OP3. The corresponding figures for the detailed caliper measurements was 52% for S-X and 62% for OP3. The main cause of uninterpretability for S-X was overlapping of the teeth and for OP3 poor resolution. For the bite wings the frequency of uninterpretability was 11%. The Status-X radiographs permitted detailed diagnosis of the periodontal status for 81% of the incisors. The rotational panoramic radiographs permitted detailed analysis of 68% of the lower premolars. The bite wings permitted evaluation of all the bone supports of premolars and upper molars. When combining all three radiographic methods detailed interpretation was possible for 91% of the marginal bone supports. The corresponding frequencies of alternative combinations were 90% for BW and S-X, 72% for BW and OP3, and 66% for S-X and OP3. The results indicate that both panoramic methods require bite wings as a complement for periodontal diagnosis in the premolar and molar regions. When also the anterior region is of interest, the combination of Status-X technique and bite wings is favourable.