{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T17:37:07Z","timestamp":1788025027148,"version":"build-2784847793"},"reference-count":32,"publisher":"Springer Science and Business Media LLC","issue":"6","license":[{"start":{"date-parts":[[2025,5,10]],"date-time":"2025-05-10T00:00:00Z","timestamp":1746835200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,5,10]],"date-time":"2025-05-10T00:00:00Z","timestamp":1746835200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Clin Oral Invest"],"abstract":"<jats:title>Abstract<\/jats:title>\n          <jats:sec>\n            <jats:title>Objective<\/jats:title>\n            <jats:p>Since relapse after orthodontic treatment and stability and failure of CAD\/CAM fabricated and Conventional fixed retainers are widely discussed, this study investigated and compared two-year post-treatment stability after insertion of a CAD\/CAM fabricated or Conventional fixed retainer in the lower jaw.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Materials and methods<\/jats:title>\n            <jats:p>Digitized dental casts or intraoral scans of <jats:italic>n<\/jats:italic>\u2009=\u200960 patients were used for data acquisition. The patients were divided into two groups according to the retention protocol: CAD\/CAM fabricated fixed retainer (<jats:italic>n<\/jats:italic>\u2009=\u200930, mean age 16.97\u2009\u00b1\u20095.74 years) and Conventional fixed retainer (<jats:italic>n<\/jats:italic>\u2009=\u200930, mean age 15.70\u2009\u00b1\u20094.19 years). The evaluation included established procedures for dental measurements of the mandible (Intercanine Distance and Little\u00b4s Irregularity Index) before orthodontic treatment, at the end of orthodontic treatment, when the fixed retainer was inserted and two years after the insertion of the fixed retainer. All retainers were inserted by the same practitioner. Complications were recorded. Statistics included Shapiro-Wilk-, T- and Friedman-Tests. The level of significance was set at <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.05.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Results<\/jats:title>\n            <jats:p>In patients with Conventional fixed retainers the change of the Intercanine Distance between insertion of the fixed retainer and two years afterwards was significantly more pronounced than in patients with CAD\/CAM fabricated fixed retainers (ICD: \u0394 CAD\/CAM<jats:sub>t1\u2212t2<\/jats:sub>: -0.03\u2009\u00b1\u20090.22\u00a0mm; \u0394 Conventional<jats:sub>t1\u2212t2<\/jats:sub>: 0.12\u2009\u00b1\u20090.29\u00a0mm). Stability of Intercanine Distance was less in patients with Conventional fixed retainers. The change of Little\u00b4s Irregularity Index was not significant between the groups. In two patients with a Conventional fixed retainer a bonding surface was renewed within the first three months.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Conclusions<\/jats:title>\n            <jats:p>Within two years, CAD\/CAM fabricated fixed retainers showed less relapse of Intercanine Distance and fewer complications than Conventional fixed retainers.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Clinical relevance<\/jats:title>\n            <jats:p>Considering the amount of relapse and the differences in complications, CAD\/CAM fabricated fixed retainers and Conventional fixed retainers are useful appliances for stabilization of treatment results with favorable stability. Fabrication of CAD\/CAM based fixed retainers is aside from that timesaving compared to Conventional fixed retainers.<\/jats:p>\n          <\/jats:sec>","DOI":"10.1007\/s00784-025-06368-4","type":"journal-article","created":{"date-parts":[[2025,5,10]],"date-time":"2025-05-10T03:30:27Z","timestamp":1746847827000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Post-treatment stability after insertion of CAD\/CAM fabricated or Conventional fixed orthodontic retainers: a two-year follow-up"],"prefix":"10.1007","volume":"29","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9713-7510","authenticated-orcid":false,"given":"Maike","family":"Tabellion","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Simgen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1602-9540","authenticated-orcid":false,"given":"J\u00f6rg Alexander","family":"Lisson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,5,10]]},"reference":[{"key":"6368_CR1","doi-asserted-by":"publisher","first-page":"770","DOI":"10.1038\/s41415-021-2954-7","volume":"230","author":"D Al-Moghrabi","year":"2021","unstructured":"Al-Moghrabi D, Littlewood SJ, Fleming PS (2021) Orthodontic retention protocols: an evidence-based overview. Br Dent J 230:770\u2013776. https:\/\/doi.org\/10.1038\/s41415-021-2954-7","journal-title":"Br Dent J"},{"key":"6368_CR2","doi-asserted-by":"publisher","first-page":"241","DOI":"10.1111\/ocr.12425","volume":"24","author":"MB Alrawas","year":"2021","unstructured":"Alrawas MB, Kashoura Y, Tosun \u00d6, \u00d6z U (2021) Comparing the effects of CAD\/CAM nickel-titanium lingual retainers on teeth stability and periodontal health with conventional fixed and removable retainers: A randomized clinical trial. Orthod Craniofac Res 24:241\u2013250. https:\/\/doi.org\/10.1111\/ocr.12425","journal-title":"Orthod Craniofac Res"},{"issue":"1","key":"6368_CR3","doi-asserted-by":"publisher","first-page":"31","DOI":"10.1186\/s40510-017-0185-x","volume":"18","author":"A Andriekute","year":"2017","unstructured":"Andriekute A, Vasiliauskas A, Sidlauskas A (2017) A survey of protocols and trends in orthodontic retention. Prog Orthod 18(1):31. https:\/\/doi.org\/10.1186\/s40510-017-0185-x","journal-title":"Prog Orthod"},{"key":"6368_CR4","doi-asserted-by":"publisher","first-page":"156","DOI":"10.1016\/j.ajodo.2019.10.010","volume":"157","author":"ML Arn","year":"2020","unstructured":"Arn ML, Dritsas K, Pandis N, Kloukos D (2020) The effects of fixed orthodontic retainers on periodontal health: A systematic review. Am J Orthod Dentofac Orthop 157:156\u2013164e17. https:\/\/doi.org\/10.1016\/j.ajodo.2019.10.010","journal-title":"Am J Orthod Dentofac Orthop"},{"key":"6368_CR5","doi-asserted-by":"publisher","unstructured":"Artun J (1984) Caries and periodontal reactions associated with long-term use of different types of bonded lingual retainers. Am J Orthod 86:112\u2013118. https:\/\/doi.org\/10.1016\/0002-9416(84)90302-6","DOI":"10.1016\/0002-9416(84)90302-6"},{"key":"6368_CR6","doi-asserted-by":"publisher","first-page":"645","DOI":"10.1093\/ejo\/cjad047","volume":"45","author":"ST Aye","year":"2023","unstructured":"Aye ST, Liu S, Byrne E, El-Angbawi A (2023) The prevalence of the failure of fixed orthodontic bonded retainers: a systematic review and meta-analysis. Eur J Orthod 45:645\u2013661. https:\/\/doi.org\/10.1093\/ejo\/cjad047","journal-title":"Eur J Orthod"},{"key":"6368_CR7","doi-asserted-by":"publisher","first-page":"545","DOI":"10.1093\/ejo\/cjad033","volume":"45","author":"E Bardideh","year":"2023","unstructured":"Bardideh E, Ghorbani M, Shafaee H, Saeedi P, Younessian F (2023) A comparison of CAD\/CAM-based fixed retainers versus conventional fixed retainers in orthodontic patients: a systematic review and network meta-analysis. Eur J Orthod 45:545\u2013557. https:\/\/doi.org\/10.1093\/ejo\/cjad033","journal-title":"Eur J Orthod"},{"key":"6368_CR8","doi-asserted-by":"publisher","first-page":"39","DOI":"10.4041\/kjod.2012.42.1.39","volume":"42","author":"A Baysal","year":"2012","unstructured":"Baysal A, Uysal T, Gul N, Alan MB, Ramoglu SI (2012) Comparison of three different orthodontic wires for bonded lingual retainer fabrication. Korean J Orthod 42:39\u201346. https:\/\/doi.org\/10.4041\/kjod.2012.42.1.39","journal-title":"Korean J Orthod"},{"key":"6368_CR9","doi-asserted-by":"publisher","first-page":"487","DOI":"10.1016\/j.ajodo.2017.12.015","volume":"154","author":"R Bjering","year":"2018","unstructured":"Bjering R, Vandevska-Radunovic V (2018) Occlusal changes during a 10-year posttreatment period and the effect of fixed retention on anterior tooth alignment. Am J Orthod Dentofac Orthop 154:487\u2013494. https:\/\/doi.org\/10.1016\/j.ajodo.2017.12.015","journal-title":"Am J Orthod Dentofac Orthop"},{"key":"6368_CR10","doi-asserted-by":"publisher","first-page":"2403","DOI":"10.4103\/jpbs.jpbs_270_24","volume":"16","author":"R Chawla","year":"2024","unstructured":"Chawla R, Ansari FM, Chekka M, Akhilesh M, Deepak VA, Varma Datla PK, Ravuri P (2024) Assessment of orthodontic retention protocols and their effects on treatment stability. J Pharm Bioallied Sci 16:2403\u20132406. https:\/\/doi.org\/10.4103\/jpbs.jpbs_270_24","journal-title":"J Pharm Bioallied Sci"},{"key":"6368_CR11","doi-asserted-by":"publisher","first-page":"15","DOI":"10.1016\/j.ajodo.2016.09.009","volume":"151","author":"F Egli","year":"2017","unstructured":"Egli F, Bovali E, Kiliaridis S, Cornelis MA (2017) Indirect vs direct bonding of mandibular fixed retainers in orthodontic patients: comparison of retainer failures and posttreatment stability. A 2-year follow-up of a single-center randomized controlled trial. Am J Orthod Dentofac Orthop 151:15\u201327. https:\/\/doi.org\/10.1016\/j.ajodo.2016.09.009","journal-title":"Am J Orthod Dentofac Orthop"},{"key":"6368_CR12","doi-asserted-by":"publisher","first-page":"373","DOI":"10.4041\/kjod.2020.50.6.373","volume":"50","author":"E Gelin","year":"2020","unstructured":"Gelin E, Seidel L, Bruwier A, Albert A, Charavet C (2020) Innovative customized CAD\/CAM nickel-titanium lingual retainer versus standard stainless-steel lingual retainer: A randomized controlled trial. Korean J Orthod 50:373\u2013382. https:\/\/doi.org\/10.4041\/kjod.2020.50.6.373","journal-title":"Korean J Orthod"},{"key":"6368_CR13","first-page":"1","volume":"18","author":"X Hu","year":"2019","unstructured":"Hu X, Ling J, Wu X (2019) The CAD\/CAM method is more efficient and stable in fabricating of lingual retainer compared with the conventional method. Biomed J Sci Tech Res 18:1\u20134","journal-title":"Biomed J Sci Tech Res"},{"key":"6368_CR14","doi-asserted-by":"publisher","first-page":"cjae040","DOI":"10.1093\/ejo\/cjae040","volume":"46","author":"U Hussain","year":"2024","unstructured":"Hussain U, Kunwar SS, Khan UW, Alnazeh AA, Kamran MA, Alam S, Aziz A, Zaheen M, Pandis N, Campobasso A (2024) Can vacuum-formed retainers maintain arch dimensions and alignment compared to Hawley and fixed bonded retainers after treatment with fixed appliances? A systematic review and meta-analysis. Eur J Orthod 46:cjae040. https:\/\/doi.org\/10.1093\/ejo\/cjae040","journal-title":"Eur J Orthod"},{"key":"6368_CR15","doi-asserted-by":"publisher","first-page":"876","DOI":"10.1016\/j.jdent.2015.05.002","volume":"43","author":"A Iliadi","year":"2015","unstructured":"Iliadi A, Kloukos D, Gkantidis N, Katsaros C, Pandis N (2015) Failure of fixed orthodontic retainers: A systematic review. J Dent 43:876\u2013896. https:\/\/doi.org\/10.1016\/j.jdent.2015.05.002","journal-title":"J Dent"},{"key":"6368_CR16","doi-asserted-by":"publisher","first-page":"32","DOI":"10.1186\/s13005-021-00281-3","volume":"17","author":"M Jedli\u0144ski","year":"2021","unstructured":"Jedli\u0144ski M, Grocholewicz K, Mazur M, Janiszewska-Olszowska J (2021) What causes failure of fixed orthodontic retention? - systematic review and meta-analysis of clinical studies. Head Face Med 17:32. https:\/\/doi.org\/10.1186\/s13005-021-00281-3","journal-title":"Head Face Med"},{"issue":"3","key":"6368_CR17","doi-asserted-by":"publisher","first-page":"119","DOI":"10.1038\/sj.bdj.2015.47","volume":"218","author":"CD Johnston","year":"2015","unstructured":"Johnston CD, Littlewood SJ (2015) Retention in orthodontics. Br Dent J 218(3):119\u2013122. https:\/\/doi.org\/10.1038\/sj.bdj.2015.47","journal-title":"Br Dent J"},{"key":"6368_CR18","doi-asserted-by":"publisher","first-page":"55","DOI":"10.1177\/14653125221118935","volume":"50","author":"AC Jowett","year":"2023","unstructured":"Jowett AC, Littlewood SJ, Hodge TM, Dhaliwal HK, Wu J (2023) CAD\/CAM nitinol bonded retainer versus a chairside rectangular-chain bonded retainer: A multicentre randomised controlled trial. J Orthod 50:55\u201368. https:\/\/doi.org\/10.1177\/14653125221118935","journal-title":"J Orthod"},{"key":"6368_CR19","doi-asserted-by":"publisher","first-page":"110","DOI":"10.5152\/TurkJOrthod.2019.18080","volume":"32","author":"Y Kartal","year":"2019","unstructured":"Kartal Y, Kaya B, Fixed Orthodontic Retainers A, Review (2019) Turk J Orthod 32:110\u2013114. https:\/\/doi.org\/10.5152\/TurkJOrthod.2019.18080","journal-title":"Turk J Orthod"},{"key":"6368_CR20","doi-asserted-by":"publisher","first-page":"32","DOI":"10.1007\/s00056-020-00243-5","volume":"82","author":"Y Kartal","year":"2021","unstructured":"Kartal Y, Kaya B, Polat-\u00d6zsoy \u00d6 (2021) Comparative evaluation of periodontal effects and survival rates of memotain and five-stranded bonded retainers: A prospective short-term study. J Orofac Orthop 82:32\u201341. https:\/\/doi.org\/10.1007\/s00056-020-00243-5","journal-title":"J Orofac Orthop"},{"key":"6368_CR21","doi-asserted-by":"publisher","first-page":"88","DOI":"10.1007\/s00056-019-00169-7","volume":"80","author":"I Knaup","year":"2019","unstructured":"Knaup I, Wagner Y, Wego J, Fritz U, J\u00e4ger A, Wolf M (2019) Potential impact of lingual retainers on oral health: comparison between conventional twistflex retainers and CAD\/CAM fabricated nitinol retainers: A clinical in vitro and in vivo investigation. J Orofac Orthop 80:88\u201396. https:\/\/doi.org\/10.1007\/s00056-019-00169-7","journal-title":"J Orofac Orthop"},{"key":"6368_CR22","doi-asserted-by":"publisher","unstructured":"Ku\u010dera J, Marek I (2016) Unexpected complications associated with mandibular fixed retainers: A retrospective study. Am J Orthod Dentofac Orthop 149:202-11. https:\/\/doi.org\/10.1016\/j.ajodo.2015.07.035","DOI":"10.1016\/j.ajodo.2015.07.035"},{"key":"6368_CR23","doi-asserted-by":"publisher","unstructured":"Kumar SO, Srinidhi S, Visshishta J, Sirisha S, Ranganathan S, Priya K, Moulvi S, Mani B (2024) Evaluation of orthodontic retention protocol among orthodontist and general Dentist-A Cross-Sectional survey. J Pharm Bioallied Sci 16:1588\u20131590. https:\/\/doi.org\/10.4103\/jpbs.jpbs_1099_23","DOI":"10.4103\/jpbs.jpbs_1099_23"},{"key":"6368_CR24","doi-asserted-by":"publisher","first-page":"554","DOI":"10.1016\/0002-9416(75)90086-x","volume":"68","author":"RM Little","year":"1975","unstructured":"Little RM (1975) The irregularity index: a quantitative score of mandibular anterior alignment. Am J Orthod 68:554\u2013563. https:\/\/doi.org\/10.1016\/0002-9416(75)90086-x","journal-title":"Am J Orthod"},{"key":"6368_CR25","doi-asserted-by":"publisher","first-page":"318","DOI":"10.1179\/1465313313Y.0000000066","volume":"40","author":"MJ Meade","year":"2013","unstructured":"Meade MJ, Millett D (2013) Retention protocols and use of vacuum-formed retainers among specialist orthodontists. J Orthod 40:318\u2013325. https:\/\/doi.org\/10.1179\/1465313313Y.0000000066","journal-title":"J Orthod"},{"issue":"3","key":"6368_CR26","doi-asserted-by":"publisher","first-page":"102008","DOI":"10.1016\/j.jebdp.2024.102008","volume":"24","author":"LA Muhareb","year":"2024","unstructured":"Muhareb LA, Talsania B, Al-Jewair T, CAD\/CAM-based fixed lingual orthodontic retainers may be as effective as conventional fixed retainers (2024) J Evid Based Dent Pract 24(3):102008. https:\/\/doi.org\/10.1016\/j.jebdp.2024.102008","journal-title":"J Evid Based Dent Pract"},{"issue":"2","key":"6368_CR27","doi-asserted-by":"publisher","first-page":"cjae006","DOI":"10.1093\/ejo\/cjae006","volume":"46","author":"H Pullisaar","year":"2024","unstructured":"Pullisaar H, Cattaneo PM, Gera A, Sankiewicz M, Bili\u0144ska M, Vandevska-Radunovic V, Cornelis MA (2024) Stability, survival, patient satisfaction, and cost-minimization of CAD\/CAM versus conventional multistranded fixed retainers in orthodontic patients: a 2-year follow-up of a two-centre randomized controlled trial. Eur J Orthod 46(2):cjae006. https:\/\/doi.org\/10.1093\/ejo\/cjae006","journal-title":"Eur J Orthod"},{"key":"6368_CR28","doi-asserted-by":"publisher","DOI":"10.1007\/s00056-023-00486-y","author":"CJ Roser","year":"2023","unstructured":"Roser CJ, Bauer C, Hodecker L, Zenth\u00f6fer A, Lux CJ, Rues S (2023) Comparison of six different CAD\/CAM retainers vs. the stainless steel twistflex retainer: an in vitro investigation of survival rate and stability. J Orofac Orthop. https:\/\/doi.org\/10.1007\/s00056-023-00486-y","journal-title":"J Orofac Orthop"},{"key":"6368_CR29","doi-asserted-by":"publisher","unstructured":"Schmid-Herrmann CU, Schwieder T, Kahl-Nieke B, Koehne T (2025) Positioning accuracy and post-treatment changes in the mandibular arch after insertion of a CAD\/CAM titanium retainer. Int J Comput Dent 28;0(0):0. https:\/\/doi.org\/10.3290\/j.ijcd.b5951470","DOI":"10.3290\/j.ijcd.b5951470"},{"key":"6368_CR30","doi-asserted-by":"publisher","first-page":"87","DOI":"10.2319\/121720-1015.1","volume":"92","author":"H Shim","year":"2022","unstructured":"Shim H, Foley P, Bankhead B, Kim KB (2022) Comparative assessment of relapse and failure between CAD\/CAM stainless steel and standard stainless steel fixed retainers in orthodontic retention patients. Angle Orthod 92:87\u201394. https:\/\/doi.org\/10.2319\/121720-1015.1","journal-title":"Angle Orthod"},{"key":"6368_CR31","doi-asserted-by":"publisher","first-page":"162","DOI":"10.1038\/s41432-022-0845-7","volume":"23","author":"PAJ Steegmans","year":"2022","unstructured":"Steegmans PAJ, Cavagnetto D, Reynders RAM (2022) Which orthodontic retention protocol should I implement? A critical assessment of a randomised controlled trial. Evid Based Dent 23:162\u2013165. https:\/\/doi.org\/10.1038\/s41432-022-0845-7","journal-title":"Evid Based Dent"},{"issue":"1","key":"6368_CR32","doi-asserted-by":"publisher","first-page":"cjad079","DOI":"10.1093\/ejo\/cjad079","volume":"46","author":"G Tran","year":"2024","unstructured":"Tran G, Rucker R, Foley P, Bankhead B, Adel SM, Kim KB (2024) Relapse and failure rates between CAD\/CAM and conventional fixed retainers: a 2-year follow-up of a randomized controlled clinical trial. Eur J Orthod 46(1):cjad079. https:\/\/doi.org\/10.1093\/ejo\/cjad079","journal-title":"Eur J Orthod"}],"container-title":["Clinical Oral Investigations"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00784-025-06368-4.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00784-025-06368-4\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00784-025-06368-4.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,18]],"date-time":"2025-06-18T08:38:01Z","timestamp":1750235881000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00784-025-06368-4"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,10]]},"references-count":32,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2025,6]]}},"alternative-id":["6368"],"URL":"https:\/\/doi.org\/10.1007\/s00784-025-06368-4","relation":{},"ISSN":["1436-3771"],"issn-type":[{"value":"1436-3771","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,10]]},"assertion":[{"value":"13 February 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"29 April 2025","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"10 May 2025","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"This article does not contain any studies with human participants or animals performed by any of the authors. Ethical approval for this retrospective study was granted by the Ethical Committee of \u00c4rztekammer des Saarlandes, Saarbr\u00fccken, Germany (Decision Number: 92\/21).","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"For this type of study, formal consent is not required.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"294"}}