{"id":8275,"date":"2023-05-23T14:42:06","date_gmt":"2023-05-23T12:42:06","guid":{"rendered":"https:\/\/www.dentalcadmos.com\/?p=8275"},"modified":"2023-05-23T14:42:06","modified_gmt":"2023-05-23T12:42:06","slug":"influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files","status":"publish","type":"post","link":"https:\/\/www.dentalcadmos.com\/en\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/","title":{"rendered":"Influence of heat treatment on fatigue resistance of two NiTi endodontic files"},"content":{"rendered":"<p style=\"text-align: justify;\"><strong>OBJECTIVES:<\/strong> To evaluate the cyclic, torsional fatigue resistance and phase transformation of two heat-treated and non-heat-treated nickel-titanium reciprocating instruments.<\/p>\n<p style=\"text-align: justify;\"><strong>MATERIALS AND METHODS:<\/strong> Twenty non-heat-treated (Procodile, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) and 20 heat-treated (Procodile Q, Komet,<br \/>\nBrasseler GmbH &amp; Co., Lemgo, Germany) files (25 mm length, #25 apical diameter and 0.6 taper) were subjected to fatigue resistance tests. The dynamic cyclic fatigue was tested at 35\u00b11 \u00b0C, using a dedicated patented device, in an artificial stainless-steel canal with a 60\u00b0 angle of curvature, the plate containing the artificial canal performing a controlled axial upand- down movement at 8 mm\/s speed. The instruments were operated with a specific reciprocating motion (Reflex Dynamic\u00ae, Komet, Breasseler GmbH &amp; Co., Lemgo, Germany). Time to fracture (TtF) was recorded and the length of the fractured tips was measured. The torsional fatigue resistance was tested at room temperature (21\u00b11 \u00b0C) using a custom-made device manufactured according to ISO 3630-1. The instruments were fixed 3 mm from the tip and their shafts were rotated counterclockwise at a speed of 2 rpm until fracture. The maximum torque load (Ncm) and corresponding rotation angle at fracture were recorded. All the results were statistically analysed (p &lt;0.05). Fractographic analysis was performed using a field emission gun scanning electron microscope (FEG-SEM) to disclose the fractured surface characteristics. To assess the temperature range for phase transformations, differential scanning calorimetry (DSC) was performed on small segments of \u224820 mg mass subjected to 2 heating and 2 cooling thermal cycles at rates of 5 \u00b0C min-1 in flowing N2 atmosphere over a temperature range of -40 \u00b0C to +110 \u00b0C.<\/p>\n<p style=\"text-align: justify;\"><strong>RESULTS:<\/strong> The heat-treated instruments showed a greater resistance to dynamic cyclic fatigue as compared to the non-heat-treated sample (TtF 303\u00b118.5 s vs 220\u00b118.4 s; p &lt;0.05) and a higher resistance to torsional fracture, bearing a greater maximum thorque load (1.67\u00b10.16 vs 0.82\u00b10.07 Ncm; p &lt;0.05). No significant differences were detected between heat-treated and non-heat-treated samples in mean angular rotation to fracture (298\u00b125\u00b0 vs 312\u00b132\u00b0; p &gt;0.05) and in the mean length of the fractured fragments (p &gt;0.05). All instruments showed both ductile and brittle fracture patterns.<br \/>\nAccording to the DSC, the direct (cooling) and reverse (heating) transformations of the non-heattreated files occurred at lower temperatures (&lt;25 \u00b0C) than those of the heat-treated files (\u224850 \u00b0C), the latter thus not being austenitic at room and body temperatures at which they are operated. Also, the different transformation enthalpies suggest a multi-step transformation, likely involving R-phase formation, for heat-treated files, against a direct transition between austenitic and martensitic phase for non-heat-treated files.<\/p>\n<p style=\"text-align: justify;\"><strong>CONCLUSIONS:<\/strong> According to these findings, heat treatment of the tested files provides them with microstructural properties more suited to the clinical operating conditions and improved performances in terms of torsional and flexural strength.<\/p>\n<p style=\"text-align: justify;\"><strong>CLINICAL SIGNIFICANCE:<\/strong> Heat-treated files might be the best choice, over the traditional non-heat-treated files, when facing challenging clinical conditions, such as curved and constricted canals.<\/p>\n<p><i>Per continuare la lettura gli abbonati possono scaricare l\u2019allegato.<\/i><\/p>\n","protected":false},"excerpt":{"rendered":"<p>OBJECTIVES: To evaluate the cyclic, torsional fatigue resistance and phase transformation of two heat-treated and non-heat-treated nickel-titanium reciprocating instruments. MATERIALS AND METHODS: Twenty non-heat-treated (Procodile, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) and 20 heat-treated (Procodile Q, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) files (25 mm length, #25 apical diameter and 0.6 taper) were &hellip; <a href=\"https:\/\/www.dentalcadmos.com\/en\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/\">Continued<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v17.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Influence of heat treatment on fatigue resistance of two NiTi endodontic files - Dental Cadmos<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.dentalcadmos.com\/en\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Influence of heat treatment on fatigue resistance of two NiTi endodontic files - Dental Cadmos\" \/>\n<meta property=\"og:description\" content=\"OBJECTIVES: To evaluate the cyclic, torsional fatigue resistance and phase transformation of two heat-treated and non-heat-treated nickel-titanium reciprocating instruments. MATERIALS AND METHODS: Twenty non-heat-treated (Procodile, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) and 20 heat-treated (Procodile Q, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) files (25 mm length, #25 apical diameter and 0.6 taper) were &hellip; Continued\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/\" \/>\n<meta property=\"og:site_name\" content=\"Dental Cadmos\" \/>\n<meta property=\"article:published_time\" content=\"2023-05-23T12:42:06+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"edra\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.dentalcadmos.com\/#website\",\"url\":\"https:\/\/www.dentalcadmos.com\/\",\"name\":\"Dental Cadmos\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.dentalcadmos.com\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/#webpage\",\"url\":\"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/\",\"name\":\"Influence of heat treatment on fatigue resistance of two NiTi endodontic files - Dental Cadmos\",\"isPartOf\":{\"@id\":\"https:\/\/www.dentalcadmos.com\/#website\"},\"datePublished\":\"2023-05-23T12:42:06+00:00\",\"dateModified\":\"2023-05-23T12:42:06+00:00\",\"author\":{\"@id\":\"https:\/\/www.dentalcadmos.com\/#\/schema\/person\/dae8bc45e635361a55553f0aac0857fe\"},\"breadcrumb\":{\"@id\":\"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.dentalcadmos.com\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Influence of heat treatment on fatigue resistance of two NiTi endodontic files\"}]},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.dentalcadmos.com\/#\/schema\/person\/dae8bc45e635361a55553f0aac0857fe\",\"name\":\"edra\",\"image\":{\"@type\":\"ImageObject\",\"@id\":\"https:\/\/www.dentalcadmos.com\/#personlogo\",\"inLanguage\":\"en-US\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/e2aad0a8340bb6125c47d6b52ca5828e?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/e2aad0a8340bb6125c47d6b52ca5828e?s=96&d=mm&r=g\",\"caption\":\"edra\"},\"url\":\"https:\/\/www.dentalcadmos.com\/en\/author\/edra\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Influence of heat treatment on fatigue resistance of two NiTi endodontic files - Dental Cadmos","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.dentalcadmos.com\/en\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/","og_locale":"en_US","og_type":"article","og_title":"Influence of heat treatment on fatigue resistance of two NiTi endodontic files - Dental Cadmos","og_description":"OBJECTIVES: To evaluate the cyclic, torsional fatigue resistance and phase transformation of two heat-treated and non-heat-treated nickel-titanium reciprocating instruments. MATERIALS AND METHODS: Twenty non-heat-treated (Procodile, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) and 20 heat-treated (Procodile Q, Komet, Brasseler GmbH &amp; Co., Lemgo, Germany) files (25 mm length, #25 apical diameter and 0.6 taper) were &hellip; Continued","og_url":"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/","og_site_name":"Dental Cadmos","article_published_time":"2023-05-23T12:42:06+00:00","twitter_card":"summary_large_image","twitter_misc":{"Written by":"edra","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebSite","@id":"https:\/\/www.dentalcadmos.com\/#website","url":"https:\/\/www.dentalcadmos.com\/","name":"Dental Cadmos","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.dentalcadmos.com\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/#webpage","url":"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/","name":"Influence of heat treatment on fatigue resistance of two NiTi endodontic files - Dental Cadmos","isPartOf":{"@id":"https:\/\/www.dentalcadmos.com\/#website"},"datePublished":"2023-05-23T12:42:06+00:00","dateModified":"2023-05-23T12:42:06+00:00","author":{"@id":"https:\/\/www.dentalcadmos.com\/#\/schema\/person\/dae8bc45e635361a55553f0aac0857fe"},"breadcrumb":{"@id":"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.dentalcadmos.com\/influence-of-heat-treatment-on-fatigue-resistance-of-two-niti-endodontic-files\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.dentalcadmos.com\/"},{"@type":"ListItem","position":2,"name":"Influence of heat treatment on fatigue resistance of two NiTi endodontic files"}]},{"@type":"Person","@id":"https:\/\/www.dentalcadmos.com\/#\/schema\/person\/dae8bc45e635361a55553f0aac0857fe","name":"edra","image":{"@type":"ImageObject","@id":"https:\/\/www.dentalcadmos.com\/#personlogo","inLanguage":"en-US","url":"https:\/\/secure.gravatar.com\/avatar\/e2aad0a8340bb6125c47d6b52ca5828e?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/e2aad0a8340bb6125c47d6b52ca5828e?s=96&d=mm&r=g","caption":"edra"},"url":"https:\/\/www.dentalcadmos.com\/en\/author\/edra\/"}]}},"_links":{"self":[{"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/posts\/8275"}],"collection":[{"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/comments?post=8275"}],"version-history":[{"count":1,"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/posts\/8275\/revisions"}],"predecessor-version":[{"id":8278,"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/posts\/8275\/revisions\/8278"}],"wp:attachment":[{"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/media?parent=8275"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/categories?post=8275"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.dentalcadmos.com\/en\/wp-json\/wp\/v2\/tags?post=8275"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}