Chitosan’s Ability to Remove the Smear Layer—A Systematic Review of Ex Vivo Studies
Abstract
:1. Introduction
2. Materials and Methods
2.1. Eligibility Criteria
2.2. Search Strategy
2.3. Selection Process and Data Collection
2.4. Risk of Bias Assessment
3. Results
3.1. Selection of the Studies
3.2. Data Collection
3.2.1. Type of Teeth and Sample Size
3.2.2. Irrigation Protocols
3.2.3. Type of Chitosan Used
3.2.4. Volume and Time of Irrigation
3.2.5. Size of Apical Preparation
3.2.6. Selection of Irrigation Needle and Activation
3.2.7. Method of Smear Layer Assessment
3.2.8. Comparison of the Chitosan with Other Irrigants
3.3. Risk of Bias
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Inclusion Criteria | Exclusion Criteria |
---|---|
Ex vivo studies | Reviews |
Non-endodontically treated extracted human teeth | Letters |
Permanent teeth with fully formed apex | Opinion articles |
Sodium hypochlorite as main irrigant | Conference abstracts |
Chitosan as final irrigant | Book chapters |
SEM to observe smear layer removal | Articles with no control group |
Database | Search Strategy | Findings |
---|---|---|
PubMed | #1 ((chitosan[Title/Abstract]) OR (chitosan[MeSH Terms]) | |
#2 ((smear layer[Title/Abstract])) OR (smear layer removal[Title/Abstract]) OR (chelator[Title/Abstract]) OR (chelators[Title/Abstract]) OR (final irrigation[Title/Abstract]) OR (final irrigant[Title/Abstract]) OR (final irrigants[Title/Abstract]) OR (smear layer[MeSH Terms]) OR (chelator[MeSH Terms]) | ||
#3 ((endodontic[Title/Abstract]) OR (endodontics[Title/Abstract]) OR (root canal therapy[Title/Abstract]) OR (root canal treatment[Title/Abstract]) OR (endodontic therapy[Title/Abstract]) OR (endodontic treatment[Title/Abstract]) OR (root canal treatment[MeSH Terms]) OR (endodontics[MeSH Terms]) | ||
#1 and #2 and #3 | 30 | |
Scopus | #1 TITLE-ABS-KEY(“chitosan”) | |
#2 TITLE-ABS-KEY(“smear layer” or “smear layer removal” or “chelator” or “chelators” or “final irrigation” or “final irrigant” or “final irrigants”) | ||
#3 TITLE-ABS-KEY(“endodontic” or “endodontics” or “root canal therapy” or “root canal treatment” or “endodontic therapy” or “endodontic treatment”) | ||
#1 and #2 and #3 | 24 | |
Web of Science | #1 TS=((chitosan)) | |
#2 TS=((smear layer) OR (smear layer removal) OR (chelator) OR (chelators) OR (final irrigation) OR (final irrigant) OR (final irrigants)) | ||
#3 TS=((endodontic) OR (endodontics) OR (root canal therapy) OR (root canal treatment) OR (endodontic therapy) OR (endodontic treatment)) | ||
#1 and #2 and #3 | 48 |
Main Results | “0.2% CH and CNP have comparable chelating effects to 17% EDTA and induce remineralization of the root canal dentin” | “0.2% CH removes SL 14 with greater efficiency than 17% EDTA in a third of root canals” | “0.2% CH had same effect on SL removal compared to 17% EDTA” | “There was no significant difference between EDTA and CH solutions in all three regions of the tooth” | “The 0.2% CH solution was able to remove SL and provide statistically similar results to 15% EDTA and 10% CA” | “CH was more effective in SL removal than MTAD” |
Analysis Method | SEM 10 ×2000 1 half. C 11, M 12, A 13. 2 blinded observers | SEM ×1000 ×3000. Both halves. A. Blinded examiner | SEM ×1000 ×2000 both halves. A. 2 blinded examiners | SEM ×1000 Both halves. C, M, A. 2 blinded researchers | SEM ×350 1 half. Half M and A. 3 endodontic observers | SEM ×1000, ×2000. 1 half. C, M, A. 3 investigators |
Activation | NM 9 | Ultrasonic | NM | NM | NM | NM |
Time FI | 3′ | 5′ | 3′ | G1: NM G2, G4, G5, G6: 3′ G3: 1′ | 3’ | 3’ |
Volume FI and Needle | 5 mL 31-gauge needle | 5 mL Needle NM | 5 mL sterile 30 G needle | 5 mL Needle NM | 5 mL 0.45 × 13.0 mm needle | 5 mL Needle NM |
Type of Chitosan | Chitosan powder (90% deacetylation) | NM | Chitosan powder (>75% deacetylation) | Chitosan (>90% deacetylation) | Chitosan (90% deacetylation) | NM |
Groups FI 1 | 2 CG: (GIA: saline, GIB: NP 4 + NT 5). GII: 0.2% CH 6; GIII: 0.2% CNP 7, GIV: 17% EDTA 8 | G1: 17% EDTA, G2: CG NT; G3: 0.2% CH; G4: NT | G1: 17% EDTA, G2: 0.2% CH, G3: CG 2.5% NaOCl | G1 (CG): DW 15; G2: GO 16; G3: 17% EDTA; G4: 0.2% CH; G5: GO-EDTA; G6: GO-CH | G1: 15% EDTA; G2: 0.2% CH; G3: 10% CA 17; G4: 1% AA 18; G5: CG (no FI). | G1: (CG) saline; G2: 0.2% CH; G3: MTAD 19 |
Main Irrigant | 2.6% NaOCl 3 | 3% NaOCl | 2.5% NaOCl | 5.25% NaOCl | 1% NaOCl | 5.25% NaOCl |
Apical Diameter | X3—30 | 35 | 30 (F3) | NM | NM | NM |
Sample Size per Group | 12 CG 2 n = 6 | 10 | 8 | 10 | 5 | 10 |
Type of Teeth | Straight single-rooted Vertucci’s type I | Single-rooted | Single-rooted mandibular premolars | Incisor | Maxillary canines | Single-rooted premolars |
Author and Year | Abdelkafy, 2023 [24] | Kamble, 2017 [25] | Ratih, 2020 [26] | Sehitoglu, 2023 [27] | Silva, 2013 [28] | Zhou, 2018 [29] |
Standardization of Samples Selection (Type of Teeth) | Sample Size Calculation | Randomization | Blinding | Standardized Preparation (One Single Operator) | Reporting of Data | Result of Risk of Bias Evaluation | |
---|---|---|---|---|---|---|---|
Abdelkafy, 2023 [24] | + | + | + | − | − | + | medium |
Kamble, 2017 [25] | + | − | + | − | − | + | medium |
Ratih, 2020 [26] | + | − | − | − | − | + | high |
Sehitoglu, 2023 [27] | + | + | + | − | − | + | medium |
Silva, 2012 [28] | + | − | + | − | − | + | medium |
Zhou, 2018 [29] | + | − | − | − | − | + | high |
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Ferreira-Reguera, A.; Ferreira, I.; Pina-Vaz, I.; Martín-Biedma, B.; Martín-Cruces, J. Chitosan’s Ability to Remove the Smear Layer—A Systematic Review of Ex Vivo Studies. Medicina 2025, 61, 114. https://doi.org/10.3390/medicina61010114
Ferreira-Reguera A, Ferreira I, Pina-Vaz I, Martín-Biedma B, Martín-Cruces J. Chitosan’s Ability to Remove the Smear Layer—A Systematic Review of Ex Vivo Studies. Medicina. 2025; 61(1):114. https://doi.org/10.3390/medicina61010114
Chicago/Turabian StyleFerreira-Reguera, Ana, Inês Ferreira, Irene Pina-Vaz, Benjamín Martín-Biedma, and José Martín-Cruces. 2025. "Chitosan’s Ability to Remove the Smear Layer—A Systematic Review of Ex Vivo Studies" Medicina 61, no. 1: 114. https://doi.org/10.3390/medicina61010114
APA StyleFerreira-Reguera, A., Ferreira, I., Pina-Vaz, I., Martín-Biedma, B., & Martín-Cruces, J. (2025). Chitosan’s Ability to Remove the Smear Layer—A Systematic Review of Ex Vivo Studies. Medicina, 61(1), 114. https://doi.org/10.3390/medicina61010114