Evaluation of microcrack formation in root canals after instrumentation with different NiTi rotary file systems: A scanning electron microscopy study

Abstract

The aim of this study was to evaluate the dentinal microcrack formation of ProTaper Universal, ProTaper Next, and WaveOne. Sixty extracted mandibular molars were selected. The mesial roots were resected and randomly divided into four groups (n = 15). The canals were prepared with hand files (group 1), ProTaper Universal (group 2), ProTaper Next (group 3), and WaveOne (group 4) instrument systems. The roots were separated horizontally at 3, 6, and 9 mm from the apex. Digital images were captured at ×40 magnification using scanning electron microscopy to detect microcrack formation. Statistical analysis was performed by Pearson Chi-square test. The prevalence of microcracks in group 2, group 3, and group 4 were significantly higher when compared to group 1 (p < 0.001). Group 2, group 3, and group 4 demonstrated similar prevalence of microcracks without significant difference (p > 0.05) in all sections. All instruments caused microcracks except for hand file. The highest percentage of microcrack was recorded in 3 mm section for all groups.

The incidence of dentinal cracks during root canal preparations with reciprocating single-file and rotary-file systems: A meta-analysis

“…Of those studies, 12 were excluded after we examined the full text because they did not conform to the eligibility criteria of this review, as shown in Table 2 20,30-40) . Finally, the 8 studies that met the inclusion criteria were included [21][22][23][24][25][26][27][28] . The process involved in the study selection is shown in Fig.…”

“…Two studies 23,27) compared ProTaper and Reciproc. Five studies 22,[24][25][26]28) compared ProTaper and WaveOne. One study included both of the two comparison groups 21) .…”

“…In the ProTaper vs. WaveOne group, 6 studies 21,22,[24][25][26]28) involving 720 teeth slices were included. Considerable heterogeneity was found Review authors' judgments about each risk of bias item presented as percentages across all included studies.…”

“…We found that they were homogeneous. In this way, 5 studies 22,[24][25][26]28) were eligible to be in the ProTaper vs. WaveOne group. The results indicated that the WaveOne system produced fewer dentinal cracks, with a total RR of 1.74 (p=0.0005, I 2 =39%).…”

“…Several researchers reported that fullsequence rotary-file instruments induce fewer dentinal cracks than reciprocating single-file systems 21,22) . However, others stated that there was no significant difference in dentinal crack formation between these two systems [23][24][25] . The results of some experiments even indicated that full-sequence rotary-file instruments were associated with more dentinal defects than reciprocating single-file systems [26][27][28] .…”