Effect of Aging on Dentinal Crack Formation after Treatment and Retreatment Procedures: a Micro-CT Study

Abstract

In order to evaluate the volume of dentinal cracks taking into account the age of the dentin and the type of file system used for endodontic procedures, forty freshly extracted single-rooted lower incisive teeth presenting similar root volume, were divided into two groups according to the age of the patient: Group Young (18 - 30 years old) and Group Old (60 years old or more). Each specimen was scanned by microcomputed tomography (micro-CT) in three stages: (i) before any treatment, (ii) after endodontic treatment with Reciproc files (REC), and (iii) after subsequent endodontic retreatment. Each group was subdivided into two subgroups, according to the retreatment technique used: retreatment with REC or with ProTaper Universal Retreatment (PUR) files. For each subgroup, the images were analyzed for differences in the volume of dentinal cracks in the middle and apical thirds of the teeth , according to the dentin age. In both stages (before and after instrumentation), the micro-CT images of the old root dentin presented with higher volume of cracks than those of the young root dentin, statistical significance notwithstanding (p>0.01). The use of REC files appeared to have no statistically significant differences in the generation of cracks in any type of root dentin when compared with PUR files (p>0.01). When retreated with PUR, the old root dentin presented with a significantly higher volume of cracks (p<0.01) when compared with the old root dentin initially.

Evaluation of Three Ni-Ti Systems in Retreatment of Curved Root Canals Obturated by Gutta-Percha With iRoot SP

“…The increasing dentinal microcracks in PTR was more than that in other groups, this may be related to the continuous rotational force and constant torque applied by the PTR rotary system on the root canal walls, and the lower exibility of PTR than other two systems [34,35]. However, additional studies are necessary to evaluate the changes in original microcracks morphology from cross-sectional images after retreatment.…”

Transparent dentin region in the tooth root

“…Transparent dentin is brittle in comparison with healthy dentin; it is also weaker 1 . Thus, transparent dentin is more fragile and susceptible to cracks, 2 which cause root fractures. Symptoms of root fractures are dull pain, gingival swelling, and sinus tracts that lead to deep localized periodontal pockets and vertical bone defects.…”

The exploration of a compound cone-beam CT contrast agent for diagnosis of human extracted cracked tooth

“…Therefore, multiple examinations including percussion, biting, staining, transillumination, thermal pulp tests [ [12] , [13] , [14] , [15] , [16] ], Cone-beam computed tomography (CBCT) [ 17 , 18 ] and microscopy [ 19 ] are used to verify cracked tooth clinically. In addition, several experimental techniques are being investigated for their potential in detecting dental cracks, including ultrasound [ 20 ], micro-CT [ 10 , 11 , 21 ], optical coherence tomography [ 22 , 23 ] and quantitative light-induced fluorescence [ 24 ]. However, due to feasibility limitations of these techniques, none of them have been implemented in clinical practice thus far.…”