Evaluation of a limited cone-beam volumetric imaging system: comparison with film radiography in detecting incipient proximal caries.

OBJECTIVES: To assess the accuracy of a limited cone-beam volumetric imaging system in detecting incipient proximal caries. STUDY DESIGN: Fifty extracted premolars were used. On 100 surfaces examined, 71 proximal carious lesions were found; 47 were limited to the enamel, and 24 penetrated into the dentin. A limited cone-beam volumetric imaging system (CBVI), 3D Accuitomo (J. Morita Mfg. Corp., Kyoto, Japan), was used. Insight films (Eastman Kodak, Rochester, NY) were used for comparison. Seven experienced oral radiologists determined the presence of lesions using a continuous rating scale. The area measure (Az) values were calculated from the receiver operating characteristic curve obtained for each modality and observer. RESULTS: The mean Az-values were 0.63 +/- 0.02 for 3D Accuitomo and 0.63 +/- 0.03 for film. Analysis of variance showed no statistically significant difference between 3D Accuitomo and film. CONCLUSIONS: A limited CBVI, 3D Accuitomo, could not enhance the accuracy in detecting proximal carious lesions.

Physical properties and ease of operation of a wireless intraoral x-ray sensor.

OBJECTIVE: A wireless CMOS (CDR Wireless) system was evaluated based on its physical properties and ease of operation. STUDY DESIGN: The physical properties were assessed by dose-response curve, modulation transfer function, and detective quantum efficiency tests. The range of signal receptivity between the sensor and the antenna was also determined. The time required to make a radiograph was measured. Using a visual analog scale (VAS), 10 test patients were asked to evaluate the discomfort caused by having the sensor inserted and placed in the mouth. An intraoral x-ray film packet and a wired CDR sensor were also evaluated for comparison with the wireless system. RESULTS: The physical properties of the wireless system and the wired CDR sensor were essentially equal. The antenna could receive the signal up to 3.5 m from the sensor. The wireless CMOS system required less time to perform the radiographic task than the other methods studied. The VAS scores for the wireless and wired CDR sensors were comparable. CONCLUSIONS: The CDR Wireless sensor has equivalent physical properties to its wired counterpart and may be more convenient to use.