Dentist-assessed risk status and internal cracks in extracted cracked teeth

Objectives: To ascertain if dentists’ assessment of the immediacy of treatment needs for cracked teeth correlates with the total number of cracks and/or number of cracks in dentin as determined via tooth autopsy.
Methods: Dentists from the Practice-based-Research in Oral-Health network (PROH-PBRN) evaluated extracted teeth with a range in the severity of external cracks. Dentists performed assessments of external tooth- and crack-level characteristics and ranked the perceived need for treatment on a 4-level scale: 1) no treatment; 2) treatment required within 1 year; 3) treatment required within 6 months; 4) immediate treatment. Teeth were immersed in methylene blue dye for 2-3 days, sectioned in 0.5-1.0mm increments on a CNC former (Univ Iowa) and each section digitally imaged. Images of each section were evaluated for number and extent of cracks internally. Spearman’s rho was used to calculate the correlation between the total number of cracks/tooth (n=94) and dentist-assessed risk status; and between number of cracks extending into dentin/tooth (n=103) and dentist-assessed risk status (p<0.05).
Results: 29 network dentists assessed 103 extracted cracked teeth. There was no correlation between the total number of cracks/tooth and dentist-assessed risk status (r=0.004; p=0.97) for that tooth. There was moderate and significant correlation between the number of cracks that extended into dentin and dentist-assessed risk status (r=0.59; p<0.0001).
Conclusions: The total number of cracks that extended into dentin as determined via tooth autopsy, but not the total number of cracks, was associated with dentists’ perception of the immediacy for tooth treatment. This suggests that dentists using conventional assessment techniques including visual examination, tactile perception and transilluminated light are moderately successful at determining cracked tooth risk status, with teeth that have cracks that traverse the DEJ into dentin representing one such risk factor. Supported by OHSU SoD dean’s research grant.