The effects of developer age on diagnostic accuracy: a study using assessment of endodontic file length.
OBJECTIVE
To examine the effects of developer age on image quality.


METHODS
Endodontic files, size 10 and 15, were placed in upper and lower molars and premolars up to the root apex or 1.5 mm short. A series of radiographs were made with each of three film types: Dentus M2 (Agfa-Gevaert, Mortsel, Belgium), Ektaspeed Plus and Ultra-speed (Kodak Eastman Co, Rochester, USA). The films were processed bi-weekly using the same Agfa chemicals (Heraeus Kulzer, Dormagen, Germany) over a 6-week period. An additional set of Dentus M2 films was processed using Periomat chemicals (Dürr Dental, Bietigheim-Bissingen, Germany). The films were viewed by eight dentists who rated the position of the tip of the file using a 5-point confidence scale. ROC data were analysed by means of analysis of variance. Az value was the dependent variable, whereas observer age group was entered as between subject factor. The null hypothesis was rejected when P<0.05.


RESULTS
The diagnostic accuracies of the three films were comparable during the first 4 weeks. In the sixth week Ultra-speed was significantly better than the other two films (P=0.046). The Periomat chemicals showed significantly greater consistency than the Agfa chemicals (P=0.004). Developer exhaustion significantly affected the performance of the older observers (P=0.008), especially when Agfa chemicals and file size 10 were used.


CONCLUSIONS
Agfa chemicals older than 4 weeks significantly affect the assessment of endodontic file length. In earlier stages there are no significant differences between the three films tested. Dentus M2 and Ektaspeed Plus films should be used as they require lower exposures.
Syriopoulos
K
K
Department of Oral Radiology, Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands.
Sanderink
G C
GC
Velders
X L
XL
van Ginkel
F C
FC
van der Stelt
P F
PF
D000328:Adult; D000704:Analysis of Variance; D006801:Humans; D008875:Middle Aged; D015588:Observer Variation; D012372:ROC Curve; D011856:Radiographic Image Enhancement; D011861:Radiography, Dental; D012996:Solutions / Q000737:chemistry; D013679:Technology, Radiologic; D013997:Time Factors; D014962:X-Ray Film
D012996:Solutions