Incidence Of Dentinal Cracks During Root Canal Preparations With Reciprocating Single-file And Rotary-file Systems:a Meta-analysis

Objective: As a dangerous factor in vertical root fracture,dentinal crack formation is often associated with root canal instruments.We conducted this meta-analysis to compare the influence of two types of nickel titanium(Ni Ti)instruments that have different movements(reciprocating single-file versus full-sequence rotary file systems)on dentinal cracks formation during root canal preparation.Methods: Searches were conducted in Pub Med,ISI Web of Knowledge,Embase and Cochrane Library using a combination of keywords.Titles and abstracts of all articles were independently assessed by two reviewers in accordance with the predefined inclusion criteria.Relevant studies were acquired in full-text form.Data in these articles were independently extracted.A meta-analysis was conducted using Review Manager 5.3.Results: Seven studies satisfied the eligibility criteria.Five studies were eligible to be in the Pro Taper vs.Wave One group.The results indicated that the Wave One system produced fewer dentinal cracks,with a total RR of 1.74(p=0.0005,I2=39%).In the Pro Taper vs.Reciproc group,two studies were included.The results indicated that the Reciproc system produced fewer dentinal cracks,with a total RR of 2.36(p=0.04,I2= 0.0%).When combining the 2 subgroups,the total heterogeneity among the 7 studies was slight(p< 0.00001,I2=17%).Furthermore,results remained the same(RR=1.81;95% CI,1.42–2.32).Conclusion: The Wave One and Reciproc files with a reciprocating motion produced significantly fewer dentinal cracks than the conventional rotational Pro Taper technique.