An evaluation of the diagnostic yield from bitewing radiographs of small approximal and occlusal carious lesions in a low prevalence sample in vitro using different film types and speeds.
OBJECTIVE
To compare diagnostic yield in caries diagnosis from D- and E-speed films.


METHODS
A laboratory study.


METHODS
A UK dental school between 1992 and 1994.


METHODS
96 extracted teeth containing approximal and occlusal lesions, but representing a low caries prevalence sample, were set in occluding dental arches. Bitewing radiographs were taken and interpreted by 5 examiners for the presence or absence of caries. Each examiner was also asked which film image he or she subjectively liked best.


METHODS
The teeth were subsequently sectioned and histologically examined to validate diagnostic decisions.


RESULTS
For all film types the percentage of lesions with caries histologically in dentine correctly identified radiologically (sensitivity) was low (approximal caries 8-22%; occlusal caries 0-30%). The number of sound dentine sites correctly identified (specificity) was high (approximal caries 98-100%; occlusal caries 79-100%). There were no significant differences between D- and E-speed films. Sensitivity was unaffected by each examiner's subjective preference for a particular film. The variation in sensitivity of diagnosis was due to differences between examiners.


CONCLUSIONS
The reluctance of many GDPs to use E-speed film because they 'do not like the image' cannot be endorsed or supported. Both E-speed film types examined can be recommended for use in general practice.
Ricketts
D N
DN
Guy's Hospital Dental School, United Medical & Dental Schools of Guy's & St Thomas's Hospitals, London.
Whaites
E J
EJ
Kidd
E A
EA
Brown
J E
JE
Wilson
R F
RF
D000704:Analysis of Variance; D003731:Dental Caries / Q000000981:diagnostic imaging*; D006801:Humans; D016300:Radiography, Bitewing / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014962:X-Ray Film