{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T04:48:45Z","timestamp":1785905325366,"version":"3.56.0"},"reference-count":23,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T00:00:00Z","timestamp":1785715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union","doi-asserted-by":"crossref","award":["BG-RRP-2.004-0004-C01"],"award-info":[{"award-number":["BG-RRP-2.004-0004-C01"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"crossref"}]},{"award":["BG-RRP-2.004-0004-C01"],"award-info":[{"award-number":["BG-RRP-2.004-0004-C01"]}],"id":[{"id":"https:\/\/ror.org\/019w4f821","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Dent. J.","Dentistry Journal"],"abstract":"<jats:p>Background\/Objectives: The furcation region of primary molars is a critical anatomical zone with high clinical relevance in endodontics and restorative dentistry due to its proximity to the pulp chamber and potential accessory canal communications. This study aimed to quantitatively evaluate and compare dentin mineral density in the crown and furcation regions, as well as furcation structure thickness, maximum dentin thickness, and volume, between primary first and second molars using micro-computed tomography. Methods: Thirty-eight extracted primary molars (19 first and 19 second molars) with physiological root resorption affecting less than two-thirds of the root length were included. Teeth were scanned using a SkyScan 1272 micro-CT system. Mineral density was calibrated using 0.3 and 1.25 g\/cm3 hydroxyapatite phantoms. Morphometric parameters of the furcation dentin were analyzed with CTAn software. Statistical analysis was performed using non-parametric tests (p &lt; 0.05). Results: Dentin mineral density was significantly lower in the furcation region compared to the crown in both first (median: 1.64 g\/cm3, IQR: 1.62\u20131.68 vs. 1.84 g\/cm3, IQR: 1.82\u20131.90) and second molars (1.71 g\/cm3, IQR: 1.70\u20131.73 vs. 1.96 g\/cm3, IQR: 1.93\u20131.96) (p &lt; 0.001). Second primary molars showed significantly higher mineral density, greater furcation structure thickness (1.50 mm vs. 1.30 mm), maximum dentin thickness (1.86 mm vs. 1.53 mm), and furcation dentin volume (80.8 mm3 vs. 46.2 mm3) than first molars (all p &lt; 0.05). Accessory canals were detected in 15.79% of specimens. Conclusions: This study demonstrates significantly lower mineralization in the furcation region compared to coronal dentin in primary molars, with first molars exhibiting lower mineral density and thinner furcation structure than second molars. These anatomical and compositional differences highlight the furcation area as a vulnerable zone and suggest the potential value of considering tooth-specific approaches in clinical management. Further clinical studies are warranted to evaluate the implications for treatment outcomes.<\/jats:p>","DOI":"10.3390\/dj14080473","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T11:50:21Z","timestamp":1785757821000},"page":"473","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Micro-CT Assessment of Dentin Mineral Density and Furcation Morphology in Primary First and Second Molars"],"prefix":"10.3390","volume":"14","author":[{"given":"Maria","family":"Kirilova","sequence":"first","affiliation":[{"name":"Department of Pediatric Dentistry, Faculty of Dental Medicine, Medical University Sofia, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9005-463X","authenticated-orcid":false,"given":"Ralitsa","family":"Bogovska-Gigova","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Faculty of Dental Medicine, Medical University Sofia, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zdravka","family":"Yaneva","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Faculty of Dental Medicine, Medical University Sofia, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1577-4362","authenticated-orcid":false,"given":"Krasimir","family":"Hristov","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Faculty of Dental Medicine, Medical University Sofia, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Dieguez-Perez, M., and Ticona-Flores, J.M. (2022). Three-Dimensional Analysis of the Pulp Chamber and Coronal Tooth of Primary Molars: An In Vitro Study. Int. J. Environ. Res. Public Health, 19.","DOI":"10.3390\/ijerph19159279"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1016\/S0300-5712(03)00045-9","article-title":"Micro-mechanical characterisation of the properties of primary tooth dentine","volume":"31","author":"Angker","year":"2003","journal-title":"J. Dent."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1069","DOI":"10.1016\/j.dental.2017.07.005","article-title":"The interrelationship of microstructure and hardness of human coronal dentin using reference point indentation technique and micro-Raman spectroscopy","volume":"33","author":"Seyedmahmoud","year":"2017","journal-title":"Dent. Mater."},{"key":"ref_4","first-page":"361","article-title":"Evaluation of Pulp Chamber Dimensions of Primary Molars from Bitewing Radiographs","volume":"37","author":"Dabawala","year":"2015","journal-title":"Pediatr. Dent."},{"key":"ref_5","first-page":"198","article-title":"The prevalence of furcation foramina in primary molars","volume":"11","author":"Ringelstein","year":"1989","journal-title":"Pediatr. Dent."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1111\/ipd.12178","article-title":"An investigation of accessory canals in primary molars\u2014An analytical study","volume":"26","author":"Sharma","year":"2016","journal-title":"Int. J. Paediatr. Dent."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"4431399","DOI":"10.1155\/tswj\/4431399","article-title":"Comparative Evaluation of Deciduous and Permanent Coronal Caries Using Polarizing Light Microscopy and Scanning Electron Microscopy","volume":"2025","author":"Thomas","year":"2025","journal-title":"Sci. World J."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"250","DOI":"10.3109\/00016357.2015.1104721","article-title":"Evaluation of root canal morphology of human primary molars by using CBCT and comprehensive review of the literature","volume":"74","author":"Ozcan","year":"2016","journal-title":"Acta Odontol. Scand."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1111\/idj.12074","article-title":"The primary and mixed dentition, post-eruptive enamel maturation and dental caries: A review","volume":"63","author":"Lynch","year":"2013","journal-title":"Int. Dent. J."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1429286","DOI":"10.1155\/2016\/1429286","article-title":"Comparison of Two Base Materials Regarding Their Effect on Root Canal Treatment Success in Primary Molars with Furcation Lesions","volume":"2016","author":"Arikan","year":"2016","journal-title":"Biomed. Res. Int."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1016\/j.joen.2021.11.015","article-title":"Interradicular Canals in 213 Mandibular and 235 Maxillary Molars by Means of Micro-computed Tomographic Analysis: An Ex Vivo Study","volume":"48","author":"Anderegg","year":"2022","journal-title":"J. Endod."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"41881","DOI":"10.1021\/acsami.4c07388","article-title":"Caries-Prone Primary Teeth: A Hidden Reason and Prophylactic Treatment in the Viewpoint of Materials Science","volume":"16","author":"Shen","year":"2024","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1159\/000485983","article-title":"Microcomputed Tomography Evaluation of Dentine Mineral Concentration in Primary Molars Managed by Three Treatment Protocols","volume":"52","author":"Mijan","year":"2018","journal-title":"Caries Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1111\/idj.12219","article-title":"Clinical, mineral and ultrastructural changes in carious dentin of primary molars after restoration","volume":"66","author":"Chibinski","year":"2016","journal-title":"Int. Dent. J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"295","DOI":"10.17796\/jcpd.35.3.918k0t3270v01285","article-title":"Microstructure of mineralized tissues in human primary teeth","volume":"35","author":"Ruschel","year":"2011","journal-title":"J. Clin. Pediatr. Dent."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1002\/jemt.23005","article-title":"FT-Raman spectroscopy, micro-EDXRF spectrometry, and microhardness analysis of the dentin of primary and permanent teeth","volume":"81","author":"Torres","year":"2018","journal-title":"Microsc. Res. Tech."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"303","DOI":"10.5624\/isd.20220007","article-title":"Micro-computed tomography for assessing the internal and external voids of bulk-fill composite restorations: A technical report","volume":"52","author":"Tosco","year":"2022","journal-title":"Imaging Sci. Dent."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1007\/s40368-014-0117-0","article-title":"Root canal morphology of primary molars: A micro-computed tomography study","volume":"15","author":"Fumes","year":"2014","journal-title":"Eur. Arch. Paediatr. Dent."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1007\/s11282-018-0315-2","article-title":"Evaluation of permanent and primary enamel and dentin mineral density using micro-computed tomography","volume":"35","author":"Sakamoto","year":"2019","journal-title":"Oral Radiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1007\/s40368-025-01118-2","article-title":"Micro-CT characterisation of the furcation area in human primary molars","volume":"27","author":"Duarte","year":"2026","journal-title":"Eur. Arch. Paediatr. Dent."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1111\/j.1600-0722.2004.00123.x","article-title":"Influence of hydration and mechanical characterization of carious primary dentine using an ultra-micro indentation system (UMIS)","volume":"112","author":"Angker","year":"2004","journal-title":"Eur. J. Oral Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1445","DOI":"10.1017\/S1431927613012725","article-title":"Tubule density and diameter in coronal dentin from primary and permanent human teeth","volume":"19","author":"Lenzi","year":"2013","journal-title":"Microsc. Microanal."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"173","DOI":"10.4103\/jisppd.jisppd_135_25","article-title":"Prevalence of accessory canals in furcation area in primary molar teeth\u2014A systematic review and meta-analysis","volume":"43","author":"Shah","year":"2025","journal-title":"J. Indian Soc. Pedod. Prev. Dent."}],"container-title":["Dentistry Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2304-6767\/14\/8\/473\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T04:18:40Z","timestamp":1785903520000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2304-6767\/14\/8\/473"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,3]]},"references-count":23,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["dj14080473"],"URL":"https:\/\/doi.org\/10.3390\/dj14080473","relation":{},"ISSN":["2304-6767"],"issn-type":[{"value":"2304-6767","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,3]]}}}