{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T22:59:00Z","timestamp":1785106740828,"version":"3.55.0"},"reference-count":27,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T00:00:00Z","timestamp":1785024000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T00:00:00Z","timestamp":1785024000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Int Endodontic J"],"abstract":"ABSTRACT<\/jats:title>\n \n Aim<\/jats:title>\n To compare the ability of Reciproc Minima instruments (sizes 20 and 25) and Reciproc Blue R25 to reach the full working length (FWL) in the mesial canals of mandibular molars without prior scouting or glide path preparation.<\/jats:p>\n <\/jats:sec>\n \n Methodology<\/jats:title>\n \n A total of 330 mesial canals from 165 extracted mandibular molars were included. Teeth with curvature of 0\u00b0\u201320\u00b0 were randomly allocated to three groups (\n n<\/jats:italic>\n \u2009=\u2009110 canals): Reciproc Blue R25, Reciproc Minima 25, or Reciproc Minima 20. No scouting or glide path preparation was performed. Canal preparation was carried out in reciprocating motion according to the manufacturers' instructions. In canals where Reciproc Blue R25 failed to reach the FWL, Reciproc Minima 25 and, if necessary, Reciproc Minima 20 were used. The primary outcome was the frequency of reaching the FWL. Secondary outcomes included instrument fracture, deformation, and preparation time. Canals in which the FWL was not reached were analysed by micro\u2010CT to investigate anatomical factors. Data were analysed using chi\u2010squared, Kruskal\u2013Wallis, Bonferroni post hoc, and McNemar tests (\n \u03b1<\/jats:italic>\n \u2009=\u20090.05).\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n The frequency of reaching the FWL differed significantly among the instruments (\n p<\/jats:italic>\n \u2009<\u20090.001). Reciproc Blue R25 reached the FWL in 70.91% of canals, Reciproc Minima 25 in 83.64%, and Reciproc Minima 20 in 96.36%. No instrument fractures occurred, and deformation rates were low and comparable among groups (\n p<\/jats:italic>\n \u2009=\u20090.552). Among canals in which Reciproc Blue R25 failed to reach the FWL, Reciproc Minima 25 failed to reach the FWL in all cases. However, Reciproc Minima 20 subsequently achieved the FWL in 78.13% and 83.33% of Reciproc Blue R25 and Reciproc Minima 25 cases, respectively (\n p<\/jats:italic>\n \u2009<\u20090.001). Preparation time also differed significantly among groups (\n p<\/jats:italic>\n \u2009<\u20090.001), with Reciproc Minima 20 reaching the FWL faster than both Reciproc Blue R25 and Reciproc Minima 25.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n Reciproc Minima instruments showed greater ability than Reciproc Blue R25 to mechanically scout mesial canals of mandibular molars. Reciproc Minima 20 showed the highest frequency of reaching the FWL, including in canals where larger instruments failed, without increasing deformation or fracture and with shorter preparation times.<\/jats:p>\n <\/jats:sec>","DOI":"10.1111\/iej.70228","type":"journal-article","created":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T21:59:30Z","timestamp":1785103170000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Full Working Length Negotiation in Challenging Narrow Canals Using a Single Conservative Asymmetric Reciprocating Instrument"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9972-6861","authenticated-orcid":false,"given":"Felipe Gon\u00e7alves","family":"Belladonna","sequence":"first","affiliation":[{"name":"Department of Endodontics Fluminense Federal University Rio de Janeiro Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3491-1374","authenticated-orcid":false,"given":"Marco","family":"Sim\u00f5es\u2010Carvalho","sequence":"additional","affiliation":[{"name":"Department of Endodontics Fluminense Federal University Rio de Janeiro Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M\u00e1rio Luis","family":"Zuolo","sequence":"additional","affiliation":[{"name":"Private Practice S\u00e3o Paulo Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Cristina","family":"Carvalho","sequence":"additional","affiliation":[{"name":"Private Practice S\u00e3o Paulo Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2517-0087","authenticated-orcid":false,"given":"Iracema Cabral","family":"Ehrhardt","sequence":"additional","affiliation":[{"name":"Private Practice S\u00e3o Paulo Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristiane Prado","family":"Galdeano","sequence":"additional","affiliation":[{"name":"Private Practice S\u00e3o Paulo Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4006-5469","authenticated-orcid":false,"given":"Tiago","family":"de Mello Guimar\u00e3es","sequence":"additional","affiliation":[{"name":"Department of Endodontics Fluminense Federal University Rio de Janeiro Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6445-8243","authenticated-orcid":false,"given":"Emmanuel Jo\u00e3o Nogueira Leal","family":"Silva","sequence":"additional","affiliation":[{"name":"Department of Endodontics Fluminense Federal University Rio de Janeiro Brazil"},{"name":"Department of Endodontics Grande Rio University (UNIGRANRIO) Rio de Janeiro Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2074-0834","authenticated-orcid":false,"given":"Erick Miranda","family":"Souza","sequence":"additional","affiliation":[{"name":"Department of Dentistry II Federal University of Maranh\u00e3o S\u00e3o Lu\u00eds Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5277-9827","authenticated-orcid":false,"given":"Marco Aur\u00e9lio","family":"Versiani","sequence":"additional","affiliation":[{"name":"Department of Endodontics Fluminense Federal University Rio de Janeiro Brazil"},{"name":"Dental Specialty Center Brazilian Military Police Minas Gerais Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,7,26]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"crossref","DOI":"10.5395\/rde.2018.43.e41","article-title":"Comparison of the Ability of Reciproc and Reciproc Blue Instruments to Reach the Full Working Length With or Without Glide Path Preparation","volume":"43","author":"Ad\u0131guzel M.","year":"2018","journal-title":"Restorative Dentistry & Endodontics"},{"key":"e_1_2_11_3_1","doi-asserted-by":"crossref","DOI":"10.7717\/peerj.3583","article-title":"The Ability of Reciproc Instruments to Reach Full Working Length Without Glide Path Preparation: A Clinical Retrospective Study","volume":"5","author":"Bartols A.","year":"2017","journal-title":"PeerJ"},{"key":"e_1_2_11_4_1","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1016\/j.joen.2016.12.024","article-title":"Fracture Incidence of WaveOne and Reciproc Files During Root Canal Preparation of up to 3 Posterior Teeth: A Prospective Clinical Study","volume":"43","author":"Bueno C. S. P.","year":"2017","journal-title":"Journal of Endodontics"},{"key":"e_1_2_11_5_1","doi-asserted-by":"crossref","first-page":"449","DOI":"10.1111\/j.1365-2591.2011.01996.x","article-title":"Shaping Ability and Cleaning Effectiveness of Two Single\u2010File Systems in Severely Curved Root Canals of Extracted Teeth: Reciproc and WaveOne Versus Mtwo and ProTaper","volume":"45","author":"B\u00fcrklein S.","year":"2012","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_6_1","doi-asserted-by":"crossref","first-page":"714","DOI":"10.1111\/iej.13736","article-title":"Outcomes of Primary Root Canal Therapy: An Updated Systematic Review of Longitudinal Clinical Studies Published Between 2003 and 2020","volume":"55","author":"Burns L. E.","year":"2022","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_7_1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1111\/iej.12982","article-title":"Fracture Incidence of Instruments From a Single\u2010File Reciprocating System by Students in an Endodontic Graduate Programme: A Cross\u2010Sectional Retrospective Study","volume":"52","author":"Caballero\u2010Flores H.","year":"2019","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_8_1","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1111\/iej.13649","article-title":"Impact of Several NiTi\u2010Thermally Treated Instrumentation Systems on Biomechanical Preparation of Curved Root Canals in Extracted Mandibular Molars","volume":"55","author":"Carvalho K. K. T.","year":"2022","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_9_1","doi-asserted-by":"crossref","first-page":"993","DOI":"10.1111\/iej.12091","article-title":"The Ability of the Reciproc R25 Instrument to Reach the Full Root Canal Working Length Without a Glide Path","volume":"46","author":"De\u2010Deus G.","year":"2013","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_10_1","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1016\/j.joen.2018.10.011","article-title":"Performance of Reciproc Blue R25 Instruments in Shaping the Canal Space Without Glide Path","volume":"45","author":"De\u2010Deus G.","year":"2019","journal-title":"Journal of Endodontics"},{"key":"e_1_2_11_11_1","doi-asserted-by":"crossref","DOI":"10.1590\/0103-644020246147","article-title":"Effects of a Pre\u2010Enlargement on Fracture Incidence of Reused Reciprocating Instruments: A Clinical Study","volume":"35","author":"De\u2010Deus G.","year":"2024","journal-title":"Brazilian Dental Journal"},{"key":"e_1_2_11_12_1","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1016\/j.joen.2016.10.039","article-title":"Blue Thermomechanical Treatment Optimizes Fatigue Resistance and Flexibility of the Reciproc Files","volume":"43","author":"De\u2010Deus G.","year":"2017","journal-title":"Journal of Endodontics"},{"key":"e_1_2_11_13_1","doi-asserted-by":"crossref","first-page":"1529","DOI":"10.1111\/iej.14271","article-title":"Influence of Different Endodontic Treatment Protocols on Tooth Survival: A Retrospective Cohort Study With Multistate Analysis and Group Balancing","volume":"58","author":"Elmaasarawi A.","year":"2025","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_14_1","doi-asserted-by":"crossref","first-page":"372","DOI":"10.1111\/aej.12484","article-title":"Clinical Fracture Incidence of Rotary and Reciprocating NiTi Files: A Systematic Review and Meta\u2010Regression","volume":"47","author":"Gomes M. S.","year":"2021","journal-title":"Australian Endodontic Journal"},{"key":"e_1_2_11_15_1","doi-asserted-by":"crossref","first-page":"1778","DOI":"10.1016\/j.joen.2015.06.014","article-title":"Current Assessment of Reciprocation in Endodontic Preparation: A Comprehensive Review\u2014Part I: Historic Perspectives and Current Applications","volume":"41","author":"Grande N. 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G.","year":"2016","journal-title":"Journal of Endodontics"},{"key":"e_1_2_11_27_1","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1111\/j.1365-2591.2007.01351.x","article-title":"Canal Preparation Using Only One Ni\u2010Ti Rotary Instrument: Preliminary Observations","volume":"41","author":"Yared G.","year":"2008","journal-title":"International Endodontic Journal"},{"key":"e_1_2_11_28_1","doi-asserted-by":"crossref","first-page":"1913","DOI":"10.1016\/j.joen.2015.08.004","article-title":"Negotiability of Second Mesiobuccal Canals in Maxillary Molars Using a Reciprocating System","volume":"41","author":"Zuolo M. L.","year":"2015","journal-title":"Journal of Endodontics"}],"container-title":["International Endodontic Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/iej.70228","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/iej.70228","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/iej.70228","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T21:59:34Z","timestamp":1785103174000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/iej.70228"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,26]]},"references-count":27,"alternative-id":["10.1111\/iej.70228"],"URL":"https:\/\/doi.org\/10.1111\/iej.70228","archive":["Portico"],"relation":{},"ISSN":["0143-2885","1365-2591"],"issn-type":[{"value":"0143-2885","type":"print"},{"value":"1365-2591","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,26]]},"assertion":[{"value":"2026-03-27","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-08","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-26","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"iej.70228"}}