Non-Cochrane · intervention · PM42897518
Comparative evaluation of dentin microcrack formation after root canal preparation with different nickel-titanium instrument systems based on micro-CT: a systematic review and meta-analysis.
Li Ang, Zhang Jimin, Lin Yijun, et al. · BMC oral health · 2026 · PubMed · doi:10.1186/s12903-026-09363-7
Findings
Population Extracted human permanent teeth undergoing root canal preparation
15 findings
| Reciprocating NiTi instruments | Rotary (continuous rotation) NiTi instruments | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: Reciprocating motion group | Proportion 0.01 [0.00, 0.03] GRADE not reported 274 participants |
| Reciprocating NiTi instruments | Rotary (continuous rotation) NiTi instruments | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: Rotary motion group | Proportion 0.02 [0.01, 0.05] GRADE not reported 585 participants |
| Thermally treated NiTi instruments | Conventional (non-thermally treated) NiTi instruments | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: Conventional group | Proportion 0.09 [0.03, 0.16] GRADE not reported 164 participants |
| Thermally treated NiTi instruments | Conventional (non-thermally treated) NiTi instruments | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: Thermally treated group | Proportion 0.01 [0.00, 0.02] GRADE not reported 750 participants |
| ProTaper Gold | ProTaper Universal | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: ProTaper Universal | Proportion 0.16 [0.07, 0.27] GRADE not reported 62 participants |
| ProTaper Gold | ProTaper Universal | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: ProTaper Gold | Proportion 0.03 [0.00, 0.11] GRADE not reported 61 participants |
| ProTaper Universal in moderately to severely curved canals (20°–40°) | ProTaper Universal in mildly curved canals (<20°) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: <20° curved canal group | Proportion 0.11 [0.01, 0.21] GRADE not reported 52 participants |
| ProTaper Universal in moderately to severely curved canals (20°–40°) | ProTaper Universal in mildly curved canals (<20°) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: 20°~40° curved canal group | Proportion 0.30 [0.07, 0.65] GRADE not reported 10 participants |
| RECIPROC Blue | WaveOne Gold | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: WaveOne Gold | Proportion 0.01 [0.00, 0.08] GRADE not reported 56 participants |
| RECIPROC Blue | WaveOne Gold | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: RECIPROC Blue | Proportion 0.00 [0.00, 0.03] GRADE not reported 116 participants |
| WaveOne Gold | WaveOne (conventional) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: WaveOne | Proportion 0.00 [0.00, 0.31] GRADE not reported 10 participants |
| WaveOne Gold | WaveOne (conventional) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: WaveOne Gold | Proportion 0.01 [0.00, 0.08] GRADE not reported 56 participants |
| RECIPROC Blue | RECIPROC (conventional) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: RECIPROC Blue | Proportion 0.00 [0.00, 0.03] GRADE not reported 116 participants |
| RECIPROC Blue | RECIPROC (conventional) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Arm: RECIPROC | Proportion 0.01 [0.00, 0.06] GRADE not reported 72 participants |
| Engine-driven NiTi instrument systems (all included experimental arms) | None (single-group pooled incidence) | Incidence of new dentin microcracks (micro-CT) Immediately after root canal preparation (pre/post micro-CT scans) · Ex vivo laboratory; extracted human permanent teeth; micro-CT · Overall (all included experimental arms) | Proportion 0.02 [0.01, 0.03] GRADE not reported 24 studies · 1082 participants |
Included primary studies 24
Open in Studies| Study | Year | Also included by | Outcomes it informs here | Trial data |
|---|---|---|---|---|
| Elmsmari 2023 Drug use and HIV-1 infection: report from the Second Italian Multicenter Study. PMID:2023101 | 1991 | 1 other review | not stated | not extracted yet |
| Aggarwal 2021 Comparative Evaluation of Dentinal Microcrack Formation before and after Root Canal Preparation Using Rotary, Reciprocating, and Adaptive… PMID:34023360 | 2021 | this review only | not stated | not extracted yet |
| Aksoy 2019 Evaluation of XP-endo Shaper, Reciproc Blue, and ProTaper Universal NiTi Systems on Dentinal Microcrack Formation Using Micro-Computed… PMID:30803543 | 2019 | this review only | not stated | not extracted yet |
| Alzamanan 2025 Micro-computed tomography evaluation of dentinal cracks after root canal preparation with different endodontic rotary files: An ex vivo… PMID:40019238 | 2025 | this review only | not stated | not extracted yet |
| Arumugam 2021 Micro-computed tomography evaluation of dentinal microcracks following canal preparation with thermomechanically heat-treated… PMID:33956372 | 2021 | this review only | not stated | not extracted yet |
| Aydin 2019 Effect of Reciproc blue, XP-endo shaper, and WaveOne gold instruments on dentinal microcrack formation: A micro-computed tomographic… PMID:30729608 | 2019 | this review only | not stated | not extracted yet |
| Bayram 2017a Effect of ProTaper Gold, Self-Adjusting File, and XP-endo Shaper Instruments on Dentinal Microcrack Formation: A Micro-computed… PMID:28476466 | 2017 | this review only | not stated | not extracted yet |
| Bayram 2017b Micro-computed Tomographic Evaluation of Dentinal Microcrack Formation after Using New Heat-treated Nickel-titanium Systems. PMID:28756963 | 2017 | this review only | not stated | not extracted yet |
| Cakici 2019 Comparison of newly formed microcracks after instrumentation using protaper next, reciproc and self-adjusting file systems. PMID:31309188 | 2019 | this review only | not stated | not extracted yet |
| Cassimiro 2017 Occurence of dentinal defects after root canal preparation with R-phase, M-Wire and Gold Wire instruments: a micro-CT analysis. PMID:28577367 | 2017 | this review only | not stated | not extracted yet |
| Ceyhanli 2016 Comparison of ProTaper, RaCe and Safesider instruments in the induction of dentinal microcracks: a micro-CT study. PMID:26172031 | 2016 | this review only | not stated | not extracted yet |
| de Oliveira 2017 Micro-computed Tomographic Analysis of Apical Microcracks before and after Root Canal Preparation by Hand, Rotary, and Reciprocating… PMID:28416304 | 2017 | this review only | not stated | not extracted yet |
| De-Deus 2014 Lack of causal relationship between dentinal microcracks and root canal preparation with reciprocation systems. PMID:25146030 | 2014 | this review only | not stated | not extracted yet |
| De-Deus 2015 Micro-computed Tomographic Assessment on the Effect of ProTaper Next and Twisted File Adaptive Systems on Dentinal Cracks. PMID:25817212 | 2015 | this review only | not stated | not extracted yet |
| Deopujari 2022 Evaluation of Microcracks formed During Root Canal Preparation by Different File Systems Using Micro-computed Tomography: An In Vitro Study. PMID:35656661 | 2022 | this review only | not stated | not extracted yet |
| Katanec 2020 Incidence of Dentinal Microcracks during Root Canal Preparation with Self Adjusting File, Reciproc Blue and ProTaper Next. PMID:36704321 | 2020 | this review only | not stated | not extracted yet |
| Mandava 2018 Micro-computed tomographic evaluation of dentinal defects after root canal preparation with hyflex edm and vortex blue rotary systems. PMID:30386515 | 2018 | this review only | not stated | not extracted yet |
| Martins 2021 Micro-computed tomographic assessment of dentinal microcrack formation in straight and curved root canals in extracted teeth prepared with… PMID:33760261 | 2021 | this review only | not stated | not extracted yet |
| Miguéns-Vila 2021 Micro-computed Tomographic Evaluation of Dentinal Microcracks after Preparation of Curved Root Canals with ProTaper Gold, WaveOne Gold,… PMID:33096193 | 2021 | this review only | not stated | not extracted yet |
| Rödig 2019 Incidence of microcracks after preparation of straight and curved root canals with three different NiTi instrumentation techniques… PMID:30907062 | 2019 | this review only | not stated | not extracted yet |
| Shantiaee 2021 Micro-computed tomography assessment of dentinal microcracks after the preparation of curved root canals with rotary and reciprocal systems. PMID:34994116 | 2021 | this review only | not stated | not extracted yet |
| Soltaninejad 2025 Micro-CT evaluation of dentinal microcrack formation in mesiobuccal canals of maxillary molars following instrumentation with heat-treated… PMID:40217241 | 2025 | this review only | not stated | not extracted yet |
| Wang 2024 Formation of dentinal microcracks after root canal preparation with four kinds of mechanical nickel-titanium files. PMID:38475954 | 2024 | this review only | not stated | not extracted yet |
| Zuolo 2017 Micro-computed Tomography Assessment of Dentinal Micro-cracks after Root Canal Preparation with TRUShape and Self-adjusting File Systems. PMID:28216274 | 2017 | this review only | not stated | not extracted yet |
Overlap with other reviews
Reviews that include the same primary studies are not independent evidence. Shared counts match studies by PMID, DOI or NCT, and otherwise by author and year (a probable match). Only the non-Cochrane dental reviews have study lists, so overlap with Cochrane reviews is not counted yet.
| Review | Shared studies | Jaccard |
|---|---|---|
| Artificial intelligence for oral cancer diagnosis: a systematic review and meta-analysis of image-based and non-imaging models. (2026) | 1 | 0.02 |
Review question
| Element | Planned (methods) | Found (results) |
|---|---|---|
| Population | Extracted human permanent teeth undergoing root canal preparation | 1082 extracted human teeth (mandibular/maxillary molars, premolars and incisors) (n=24 studies) |
| Intervention | Root canal preparation with at least one engine-driven NiTi instrument system | NiTi instrument systems including RECIPROC, RECIPROC Blue, WaveOne, WaveOne Gold, ProTaper Universal, ProTaper Gold, ProTaper Next, BioRaCe, HyFlex CM, HyFlex EDM, XP-endo, TRUShape, SAF, Twisted File Adaptive and others (n=24 studies) |
| Comparison | Different NiTi instrument systems (I/C defined jointly as root canal preparation with at least one engine-driven NiTi instrument) | Other NiTi instrument systems and hand files within studies (n=24 studies) |
| Outcomes | Incidence (%) of new dentin microcracks detected by micro-CT after root canal preparation | Dentin microcrack incidence by micro-CT (n=24 studies; overall pooled incidence 2%) |
| Study designs | Ex vivo studies | Ex vivo studies (n=24) |
| Timing | Not specified (immediately after root canal preparation) | Immediately after root canal preparation |
AMSTAR 2 items
Two independent extractors rated each item. Their ratings are shown side by side because they have not been reconciled yet. The overall rating follows Shea et al. 2017: one critical flaw gives Low, more than one gives Critically Low.
| Item | Extractor A | Extractor B | Agree |
|---|---|---|---|
| 1Research question includes PICO components | Yes | Yes | yes |
| 2Protocol established before the reviewcritical | Partial Yes | Partial Yes | yes |
| 3Choice of study designs explained | Yes | Yes | yes |
| 4Comprehensive literature searchcritical | Partial Yes | Yes | no |
| 5Study selection in duplicate | Yes | Yes | yes |
| 6Data extraction in duplicate | Yes | Yes | yes |
| 7List of excluded studies with reasonscritical | No | No | yes |
| 8Included studies described in detail | Yes | Yes | yes |
| 9Risk of bias assessed satisfactorilycritical | RCT: Partial Yes · NRSI: N/A | NRSI: No · RCT: N/A | no |
| 10Funding of included studies reported | Yes | No | no |
| 11Appropriate meta-analysis methodscritical | RCT: No · NRSI: N/A | NRSI: No · RCT: N/A | no |
| 12Impact of risk of bias on the pooled results | No | No | yes |
| 13Risk of bias accounted for in interpretationcritical | Yes | No | no |
| 14Heterogeneity explained | Yes | Yes | yes |
| 15Publication bias investigatedcritical | Yes | Yes | yes |
| 16Conflicts of interest reported | Yes | Yes | yes |
| Overall | Critically Low | Critically Low | yes |