RESUMO
In order to compare the clinical utilization of diagnostic dyes to identify carious dentin, the present in vivo study compared two caries-detector dyes, acid red (1% acid red in propylene glycol wt/wt) and povidone-iodine (8% povidone-iodine in water wt/vol). A total of 221 cavities prepared by 19 senior dental students under the supervision of two teachers at the Universidad Nacional Autónoma de México Dental School were used. Dyes were applied double-blind under standardized conditions to at least two teeth of the same patient. Data were analyzed using the Mantel-Haenszel chi-square test and a test of proportions. Results showed that molars or premolars did not appear to be positively stained more frequently by one dye or another. Also, 36.7% of teeth tested positive to either one of the two dyes. Prudent utilization of either acid red or povidone-iodine appeared to be equally useful in assisting clinical decisions concerning cavity size while restoring dentinal lesions. However, povidone-iodine may be preferred in clinical settings where acid red is expensive and/or difficult to obtain. Further research is necessary to establish accurately the mechanism of staining by povidone-iodine.
