Detection of dentinal cracks using contrast-enhanced micro-computed tomography

A new technique using contrast enhanced micro-computed tomography (micro-CT) was developed to improve the ability to detect dentinal cracks in teeth and assess associated risks to oral health. Extracted, whole human molars that exhibited visual evidence of external cracks following extraction and machined, partially fractured elephant dentin specimens were labeled by BaSO4 precipitation and imaged by micro-CT. Contrast-enhanced micro-CT was demonstrated in vitro to enable non-destructive, 3-D imaging of the presence, morphology and spatial location of dentinal cracks in whole human molars and machined specimens. BaSO4 staining provided enhanced contrast for the detection of cracks that could not be detected prior to staining. Backscattered SEM micrographs showed that BaSO4 was precipitated on the surfaces of dentinal cracks and within adjacent tubules. The new methods demonstrated in this study are expected to be useful for clinical and scientific studies investigating the etiology and treatment of dentinal cracks in teeth.