Dependability of B-scan and real time measurements by a newly trained operator

Abstract A comparative trial of BPD measurements was carried out by a newly trained operator using a B-scanner and a Real Time scanner each of which was fitted with a coded cephalometer to permit repeated measurements at one examination session. The real time results were more accurate than the B-scan ones and similar to those reported by other workers. To investigate fatigue as a factor affecting the B-scan results, the within-group variability of the first and third B-scan results was considered but found to be non-significant.