Radiographic Caries Detection: A Systematic Review and Meta-analysis
One of the most common occurrences in general dental practices is the detection and diagnosis of dental caries. Early caries detection may prevent the need for invasive and expensive restorative treatment. In a systematic review and meta-analysis published in February 2015 in the Journal of Dentistry aimed to evaluate the “accuracy of radiographic caries detection for different lesions at different locations.”1
The primary method used for caries detection includes visual-tactile detection and radiographs, specifically bitewing radiographs. Alternative methods less commonly used such as fluorescence-aided caries detection, have been found to be highly sensitive yet less specific. These methods are intriguing and may eventually be used more regularly as they do not use ionizing radiation, making the use of these devices potentially less harmful than radiographs.
The specificity was found to be high for proximal surfaces and moderate for occlusal surfaces when evaluated with radiographs. However, radiography limited sensitivity for detecting any kind of carious lesion, including incipient lesions and lesions that extended into the dentin. For the detection of initial occlusal carious lesions, the fluorescence-based caries detection displayed significantly higher accuracy, sensitivity, and specificity.
However, for proximal surfaces of permanent teeth, radiographic detection is supported by more studies than fluorescence-based detection. Not surprisingly, visual-tactile detection was inferior when compared to radiographic detection when evaluating enamel, dentin, or minimally cavitated proximal lesions. Yet, visual-tactile detection is very effective for detecting occlusal and smooth-surface lesions as well as deep proximal lesions.
In addition to evaluating the difference in accuracy between radiographs, visual-tactile detection, and fluorescence-aided caries detection, the review also evaluated detection differences between primary and permanent teeth. In regard to proximal lesions in primary teeth, the authors found “fluorescence-based techniques seem more sensitive, but significantly less specific, with lower overall accuracy.”
Some limitations to this review and meta-analysis cited by the authors include only evaluating primary lesions and not focusing on secondary lesions, as well as a high risk of bias in the majority of the studies included. Many were in vitro studies which make them less applicable to a real dental setting. Even with these limitations, the authors claim, “this did not seem to generally affect accuracy measures.”
The authors conclude by stating, “current evidence finds radiographic caries detection relatively insensitive, but highly specific for detecting initial occlusal and proximal lesions. Sensitivity, specificity and overall accuracy are significantly higher for lesions extending into dentine or, for proximal lesions, those with cavitated surfaces.”
Schwendicke F, Tzschoppe M, Paris S. Radiographic caries detection: A systematic review and meta-analysis. J Dent. 2015 Aug;43(8):924-33. doi: 10.1016/j.jdent.2015.02.009. Epub 2015 Feb 24. PMID: 25724114.