Brazilian Dental Science https://bds.ict.unesp.br/index.php/cob <p>&lt;!--Página Inicial - criada fora do painel, via FTP --- templates/frontend/pages/indexJournal.tpl--&gt;</p> <p style="color: #22bae9;"><strong><img style="max-width: 95%; margin-top: 18px;" src="https://ojs2.ict.unesp.br/public/site/images/andre/shadow-small.jpg" alt="" /></strong></p> <div style="float: left;"> </div> <p style="text-align: center;"> </p> en-US <p align="center"><strong>COPYRIGHT TRANSFER AND RESPONSIBILITY STATEMENT <br /> (<a style="font-size: 10px;" href="/COPYRIGHT.pdf" target="_blank">PDF</a> | <a style="font-size: 10px;" href="/COPYRIGHT.docx" target="_blank">Word</a>)</strong></p><p>All manuscript's copyright ownership of the article "____________________________________________________________________" is transferred from the author(s) to the BRAZILIAN DENTAL SCIENCE, in the event the work is published. The manuscript has not been published elsewhere and that it has not been submitted simultaneously for publication elsewhere.</p><p>We hereby attest the study is original and does not present manipulated data, fraud or plagiarism. We made significant scientific contribution to the study and we are aware of the presented data and in agreement with the final version of the manuscript. We assume complete responsibility for the ethical aspects of the study.</p><p> </p><p><strong>This text must be printed and signed by all authors. The scanned version should be submitted as supplemental file during the submission process.</strong></p> bds.ict@unesp.br (Sergio Eduardo de Paiva Gonçalves) bds.ict@unesp.br (Rafael Cunha) Mon, 30 Jun 2025 13:23:17 +0000 OJS 3.2.1.4 http://blogs.law.harvard.edu/tech/rss 60 Comparison of gap width of thermoformed clear aligners produced by different 3D printers https://bds.ict.unesp.br/index.php/cob/article/view/4696 <p><strong>Background: </strong>Although clear aligners have been widely used in orthodontics, factors such as thickness and fit are still little studied. In addition, other clinical aspects, such as optical properties, forces and moments and predictability of movement, are fundamental issues for the consolidation of this innovative therapeutic approach. This study aimed to assess how clear aligners manufacturing is impacted by 3D printer techniques and their thermoforming processes through analysis of the model-aligner interface. <strong>Methods</strong>: Models were printed on three different printers with distinct printing technologies, namely FDM (fused deposition material), SLA (stereolithography apparatus), and DLP (digital light processor). In each case, two resolutions were investigated (i.e. 25 µm and 100 µm). Polyethylene terephthalate glycol (PETG) sheets (Track A, Forestadent<sup>TM</sup>, Germany) were made using a thermoforming machine (Plastvac P7, Bio-Art, Brazil) to simulate the orthodontic clear aligner. A universal cutting machine (IsoMet 1000 Precision Cutter, Buehler, UK) was employed to obtain sections of the model-sheet set at the central incisor, canine, first premolar, and first molar regions in the lower arch. The GAP width between models and aligners was obtained through stereomicroscopy (Zeiss, Germany) and measured with Image J/Java software, version 1.46r. Statistical differences were obtained through Analysis of variance (ANOVA) and Tukey’s posthoc test at a significance level of 5%. <strong>Results:</strong> Gap differences were smaller for SLA and DLP when compared to FDM 3D printer technologies. It was observed that smaller resolutions (100 µm) displayed higher gap widths, relating precision to higher resolutions (25 µm). The assessment of the dental regions did not reveal any distinction relating to resolution or printer techniques. <strong>Conclusion</strong>: This study showed that SLA and DLP printers produced more precise models than FDM printers used in orthodontics for clear aligners. Factors such as cost, speed and printing capacity may be more important than resolution and GAP for the production of clear aligners in orthodontics.</p> <strong>Keywords:</strong> 3D printing; Biomechanics; Clear aligners; Digital orthodontics; Orthodontic appliances. <p> </p> Murilo Matias, Eduardo Listik, Vania Heidorn, Elaine Carvalho de Souza, Cristiane Aparecida da Silva Rios, Jessica Mayara Arcanjo, Louise Marie Gouvea Pierard, Thalita Sales Fontes, Ana Carla Raphaelli Nahas Copyright (c) 2025 Brazilian Dental Science https://bds.ict.unesp.br/index.php/cob/article/view/4696 Mon, 30 Jun 2025 00:00:00 +0000 Synchronous Oral Squamous Cell Carcinoma and Oral Heterotopic Gastrointestinal Cyst: First Case Report https://bds.ict.unesp.br/index.php/cob/article/view/4798 <p><strong>Background:</strong> Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity. However, its synchronous occurrence with lesions of a different nature is exceedingly rare, particularly arising at the same anatomical site. Heterotopic gastrointestinal cysts (HGICs) are developmental anomalies containing ectopic gastrointestinal epithelium, typically observed in pediatric patients and rarely reported in adults. <strong>Objectives:</strong> This report describes an unprecedented case of synchronous OSCC and HGIC of the mouth floor, underscoring the critical role of thorough histopathological evaluation for accurate diagnosis and appropriate management. <strong>Description:</strong> A 62-year-old man presented with an ulcerated lesion on the right mouth floor. Incisional biopsy followed by histological analysis revealed two distinct lesions: one characterized by a proliferation of atypical squamous cells, consistent with OSCC, and the other by a cystic cavity lined with tall columnar epithelial cells showing basally located nuclei and apical microvilli (brush border), consistent with the diagnosis of HGIC. Definitive treatment included tumor resection and ipsilateral neck dissection. The patient remains under clinical follow-up. <strong>Conclusion:</strong> To the best of our knowledge, this is the first reported case of synchronous OSCC and HGIC at the same site, highlighting the need for individualized therapeutic planning based on the biological behavior of each lesion.</p> <p><strong>Keywords</strong></p> <p>Choristoma; Dentistry; Mouth Neoplasms; Oral Pathology; Squamous Cell Carcinoma of Head and Neck.</p> Caroline Alfaia Silva, Lidiane de Paula Ribeiro, Túlio Silva Rosa, Angélica Reinheimer, Elena Riet Correa Rivero, Filipe Modolo, Rogério de Oliveira Gondak, Ricardo Luiz Cavalcanti de Albuquerque-Júnior Copyright (c) 2025 Brazilian Dental Science https://bds.ict.unesp.br/index.php/cob/article/view/4798 Mon, 30 Jun 2025 00:00:00 +0000