Mp. Rudolphy et al., GREY DISCOLORATION FOR THE DIAGNOSIS OF SECONDARY CARIES IN TEETH WITH CLASS-II AMALGAM RESTORATIONS - AN IN-VITRO STUDY, Caries research, 30(3), 1996, pp. 189-193
Grey discolouration around occlusal amalgam restorations has been foun
d to be useful for the diagnosis of secondary caries. The aim of the p
resent in vitro study was to establish the validity of grey discoloura
tion of buccal and lingual enamel next to the approximal amalgam of cl
ass II restorations for the diagnosis of secondary caries. One hundred
buccal and lingual areas next to the approximal parts of a class II f
illing in molars and premolars were included in the study. Fifty-one a
reas showed grey discolouration. Validation was performed against radi
ographs of transverse sections. Both radiolucencies and radiopacities
were scored as being caries. The results were: sensitivity 92%, specif
icity 55%, positive predictive value 22% and negative predictive value
98%. It was concluded that grey discolouration of the approximal wall
s next to class II amalgam fillings is not useful for the detection of
secondary caries, but the absence of grey discolouration gives a good
prediction for the absence of secondary caries. This is in contrast t
o grey discolouration around occlusal amalgam restorations, which was
considered to be useful for the diagnosis of secondary caries.