MARGINAL BONE LEVEL BUCCAL TO MANDIBULAR MOLARS IN DIGITAL RADIOGRAPHS FROM CHARGE-COUPLED-DEVICE AND STORAGE PHOSPHOR SYSTEMS - AN IN-VITRO STUDY

The aim of this in vitro study was to compare bone loss measurements i n the furcation area of mandibular molars in digital radiographs from a CCD-(Sens-A-Ray(R)) and a storage phosphor (Digora(R)) system. 10 1s t and 7 2nd mandibular molars, with intact lingual but reduced buccal bone with furcation involvements, were used. Radiographs were first ta ken with lead markers at the most apical part of the buccal bone and a t the cemento-enamel junction. These radiographs were used to establis h a radiographically true distance between the CEJ and the buccal bone level. The lead marker at the CEJ served as a reference point for the observers' subsequent estimates of the extent of bone removed, which were made in radiographs without lead markers at the bone level. 1 exp osure (400 ms) for the CCD- and 5 (160 ms, 200 ms, 250 ms, 320 ms, 400 ms) for the storage phosphor system were used. Measurements were made in unprocessed (original) and processed images (contrast enhanced and /or high pass filtered). The results showed underestimation of bone lo ss, but smaller than previously reported for him radiographs. No signi ficant difference was found between the 2 systems when compared at the same exposure. Nor were any significant differences found between unp rocessed and processed images or between storage phosphor images from different exposures. We conclude that digital radiographs are comparab le to film based radiographs for measurement of buccal bone loss but t hat lower exposures can be used, especially with the storage phosphor system.