2026-02-26
Covadonga Sanchez Padilla, Oliver Valencia De Pablo, Ruth Perez-Alfayate, Antonio J Conde Villar, Gaizka Loroño, Borja Aguilar, Giampiero Rossi−Fedele, Roberto Estevez
Objective : To compare the efficacy of sodium hypochlorite (NaOCl) combined with ethylenediaminetetraacetic acid (EDTA), etidronic acid (HEDP), or Keratobacter (KB; a glycocholic acid–based solution with surfactants), for smear-layer removal, using subsonic agitation during the final rinse. Methods : Following decoronation, 40 human central mandibular incisors (single-canal) were randomly assigned into one of 3 experimental groups (n=12 each) based on the irrigant solution used (NaOCl + EDTAfinal, NaOCl + HEDP, and NaOCl + KB) or used as control specimens: positive controls (irrigation omitted) or negative controls (no chemo-mechanical preparation) (n=2 per group). Experimental groups were prepared using reciprocating instruments and irrigated with the respective solutions, with the chelator omitted for the NaOCl + EDTAfinal group at this stage. The teeth were then split, scanned with an electron microscope, and the smear layer was scored (0-3) at 3 levels by 2 blinded examiners. The reassembled specimens underwent a final rinse with the relevant solutions incorporating subsonic agitation, after which they were disassembled, and the remaining smear layer was scored as before. A non-parametric Brunner–Langer model of longitudinal data was estimated for the cleaning results for each of the levels. Then, an ATS-type ANOVA statistical test was used to analyze the effect of the irrigant, the treatment stage, and the interaction between them. The Mann–Whitney test with Bonferroni correction was used for multiple comparisons between irrigants in each phase. The significance level for all analyses was 5%. Results : Following instrumentation, negative controls were scored 0, and positive controls were scored 3. NaOCl + KB was associated with significantly lower scores compared to NaOCl + EDTAfinal and NaOCl + HEDP (coronal and apical levels) (P < .001). After the final rinse, NaOCl + KB showed significantly lower scores compared to NaOCl + HEDP coronally (P=.015), with the final rinse being associated with significantly lower scores solely for NaOCl + KB at the middle and apical levels (P=.002). Conclusions : NaOCl + KB had the lower scores for smear layer compared to the other experimental groups, with the final rinse enhancing smear layer removal for NaOCl + KB.
2026-02-26
Yuwei Wang, Ling Zou, Yuan Gao
Objective : To conduct a bibliometric analysis of the literature on C-shaped canal systems in mandibular second molars (MSMs) and to review key research themes and evolving trends. Methods : A comprehensive search of the Web of Science Core Collection (WoS-CC) was conducted for publications through 31 December 2024. Following study selection and data extraction, bibliometric data such as publication years, authors, citation counts, institutions, countries/regions, journals, and keywords were analyzed using VOSviewer, CiteSpace, SPSS, and Microsoft Excel. A related review was also performed to synthe size key research themes and evolving trends. Results : 166 publications from 1979 to 2024 met the inclusion criteria, with 50.6% published within the past 5 years. The most cited article received 239 citations. Research originated from 52 countries/regions, with China contributing the largest number of publications (n=34), followed by the United States (n=26). Wuhan University, the University of Hong Kong, and Texas A&M University were the leading institutional contributors. Journal of Endodontics (JOE) published the most articles (n=38), while International Endodontic Journal (IEJ) accumulated the highest total citations (n=1 666). James L. Gutmann was the most prolific author (n=12), and Bing Fan was the most cited (n=577). Keyword co-occurrence analysis revealed “C-shaped canal” and “cone-beam computed tomography” as the most frequent terms, while “deep learning” demonstrated a recent and marked citation burst. Conclusion : This study provides an overview of influential studies on C-shaped canal systems in MSMs and identifies key research themes and evolving trends, serving as a reference for future research and clinical practice.
2026-02-26
Maria Mihaela Iuga, Fernando Mauricio Espada Salgado, Mario George Casaretto Gamonal, Stefan V Stefanescu, Oprea Bogdan, Kavalipurapu Venkata Teja, Kaligotla Apoorva Vasundhara
Objective : This study aimed to evaluate current trends in the use of root canal irrigants, agitation techniques, and intracanal medicaments among members of the Peruvian Endodontic Society. The secondary aim was to assess how these clinical practices are influenced by the level of education and years of experience. Methods : A cross-sectional survey was conducted using a 32-item validated electronic questionnaire. The survey targeted all 445 registered members of the Peruvian Endodontic Society and was distributed in 2 rounds during February and April 2024. A total of 227 endodontists responded, yielding a 50.1% response rate. The questionnaire collected information on clinicians’ preferences for irrigant solutions, agitation methods, intracanal medicaments, and intermediate restorative materials. Statistical analyses, including chi-square and Z-tests, were performed to determine associations between clinical practices and clinician experience or level of education (significance level set at P ≤ .05). Two separate multinomial logistic regression models were used to evaluate the association between the level of education and choice of irrigant and intracanal medicament. Results : Sodium hypochlorite (NaOCl) was the irrigant of choice for 78.4% of respondents, commonly at a concentration of 2.5%-4%. Ethylenediaminetetraacetic acid (EDTA) was used by 87.8%, primarily at 17%. Syringe irrigation with side-vented needles (47%) was the predominant delivery method. Regarding agitation methods, sonic agitation was most used (41.8%), followed by manual dynamic agitation (34.8%). Calcium hydroxide was the preferred intracanal medicament (62.1%), typically used for a 2-week period. A statistically significant association was found between the level of education and irrigant selection (P = .001) as well as between years of experience and intracanal medication usage (P=.005). Conclusion : Endodontists in Peru demonstrate strong alignment with internationally recognized disinfection protocols, particularly in the use of NaOCl and EDTA. Agitation techniques and intracanal medication choices showed more consistent and evidence-aligned patterns among clinicians with greater postgraduate training and experience, highlighting the role of professional development. Endodontists in Peru demonstrate a high level of adherence to current standards and protocols regarding root canal irrigation and intracanal medication, indicating that their clinical practices are up to date with contemporary guidelines.