Er. Hewlett et al., RADIOGRAPHIC SECONDARY CARIES PREVALENCE IN TEETH WITH CLINICALLY DEFECTIVE RESTORATIONS, Journal of dental research, 72(12), 1993, pp. 1604-1608
Decisions to replace existing restorations are often based on clinical
findings of margin discrepancies and other restoration defects. Previ
ous studies have suggested that such findings do not correlate well wi
th the actual presence of secondary caries, and that treatment should
be deferred until caries is clinically or radiographically evident. Th
e purpose of this study was to assess the frequency with which clinica
lly defective restorations are associated with radiographic secondary
caries. As part of a study to assess the efficacy of guidelines for th
e ordering of dental radiographs, 6285 restored teeth in 490 subjects
were examined clinically and radiographically by three calibrated inve
stigators. Specific criteria were used to determine whether restoratio
ns were intact or defective. Of the total, 822 teeth (13%) were judged
to have clinically defective restorations. Of these, 113 teeth (14%)
had radiographic secondary caries. Of the 5463 teeth with intact resto
rations, 5% had radiographic secondary caries. We found that the likel
ihood of radiographic secondary caries was nearly three-fold higher fo
r defective restorations than for intact restorations. The large perce
ntage (86%) of defective restorations with no radiographic secondary c
aries suggests, however, that replacement of all defective restoration
s due to risk of secondary caries may constitute overtreatment. The us
e of defective restoration status and presence of radiographic seconda
ry caries as a combined criterion for replacement may potentially redu
ce such overtreatment. The prevalence of secondary caries under defect
ive restorations should be determined clinically so that the usefulnes
s of combining the criteria of defective restoration with those of rad
iographic secondary caries can be evaluated.