Eam. Kidd et al., CRITERIA FOR CARIES REMOVAL AT THE ENAMEL-DENTIN JUNCTION - A CLINICAL AND MICROBIOLOGICAL STUDY, British Dental Journal, 180(8), 1996, pp. 287-291
In the UK cavity preparation at the enamel-dentine junction (EDJ) is c
onsidered complete when all soft and/or stained tissue is removed. The
aim of the present work was to link the clinical criteria of dentine
consistency and dentine colour with the microbiological status of the
tissue. Cavities were prepared in 564 teeth. Under rubber dam, access
to the EDJ was gained and the sample sites selected (n = 847); Their c
onsistency was noted as hard or soft and wet or dry when probed. The c
olour of the site was noted as stain-free or stained. Dentine was samp
led using a round bur. After microbiological processing the total anae
robic count and counts of mutans streptococci and lactobacilli were ex
pressed as log(10) [CFU per sample]. Soft sites harboured significantl
y more bacteria than hard sites (P < 0.001). Soft and wet sites harbou
red significantly more bacteria than soft and dry sites (P < 0.001). S
tained and hard sites harboured more bacteria than stain-free and hard
sites (P < 0.05) but this difference was not considered to be clinica
lly relevant. The relatively simple clinical criteria used here correl
ated significantly with the microbial findings. All soft dentine must
be removed at the EDJ to ensure minimal infection of the underlying ha
rd dentine. However, it may not be necessary to continue preparation u
ntil the EDJ is also stain-free.