Examiner variability in the assessment of dental restorations

A series of examiner variability studies were carried out in the assessment of restorations in adults made by extended duty ancillaries (E.D.A.s). While there were some differences between the two supervising team dentists these were smaller than those found when dentists who did not work in the project were examined. The use of indirect evaluation by examining bitewing radiographs for the presence of overhangs was no improvement over the clinical examination in terms of examiner agreement, and moreover only identified half of the restorations scheduled for replacement clinically. Using the results of these experiments, it is suggested that quality control should take into account examiner variability and consequently a 3-4% sample would be sufficient to maintain standards.