Diagnostic Methods for Detecting Dental Cracks: A Systematic Review

Background: Dental cracks are a common yet diagnostically challenging condition due to their asymptomatic clinical nature and difficulty in early detection. Accurate diagnosis is essential to prevent crack progression and potential tooth loss; however, no universally accepted diagnostic method exists. Objectives: To systematically evaluate the diagnostic methods used for detecting dental cracks and analyze their effectiveness and limitations according to the available scientific literature. Materials and Methods: A systematic review of diagnostic test accuracy studies was conducted following the PRISMA 2020 guidelines in the PubMed and SCOPUS academic databases using the following keywords and Boolean operators ("cracked tooth" OR "cracked tooth syndrome" OR "tooth cracks" OR "dental cracks" OR "enamel cracks") AND (diagnosis OR diagnostic OR detection OR imaging OR "diagnostic accuracy"). The search included studies published within the last 10 years, written in English, and with free full-text availability. Diagnostic test accuracy studies evaluating clinical or imaging methods for detecting dental cracks were included. Study selection, data extraction, and risk-of-bias assessment using the QUADAS-2 tool were performed independently by two reviewers. Owing to methodological heterogeneity, a qualitative synthesis of the evidence was undertaken. Results: The literature search identified 81 records, of which 12 studies met the eligibility criteria and were included in the systematic review. The evaluated diagnostic methods included visual examination, transillumination, quantitative light-induced fluorescence, cone-beam computed tomography, contrast-enhanced cone-beam computed tomography, optical coherence tomography, magnetic resonance imaging, and artificial intelligence-assisted image analysis. Considerable variability in diagnostic performance was observed among the evaluated methods. Optical coherence tomography demonstrated the highest diagnostic accuracy for detecting enamel and dentinal cracks, whereas contrast-enhanced cone-beam computed tomography improved crack detection compared with conventional cone-beam computed tomography. Conventional clinical methods remained useful as initial screening tools but showed limited diagnostic accuracy when used alone. Conclusions: No single diagnostic method demonstrated consistently high diagnostic accuracy for all types of dental cracks. Current evidence supports a multimodal diagnostic approach that combines conventional clinical examination with advanced imaging techniques when indicated to improve diagnostic reliability and facilitate treatment planning. However, the available evidence remains heterogeneous, highlighting the need for additional high-quality diagnostic test accuracy studies using standardized reference standards and reporting methods.