Controlled heating between 100 and 500 degrees celsius improves enamel resistance to erosion in vitro

Scientific Reports, vol. 16

Abstract

This study aimed to investigate the effect of controlled heating at different temperatures on enamel erosion resistance, One hundred and twelve polished bovine enamel samples were randomly allocated to one of seven groups (n = 16): no treatment (negative control [C]); daily application of fluoride solution (500 ppm F-, 800 ppm Sn2+ as AmF/NaF/SnCl2, pH4.5, standard control [F]); and five oven-heated groups (100 °C, 200 °C, 300 °C, 400 °C, 500 °C). Heating in a dental oven was conducted atrates of 1 K/min, and each temperature level was maintained for 1 min. After surface treatment, all samples underwent a six-day erosive cycling protocol, with six daily immersions in citric acid (0.05 M, pH 2.3, 2 min) and storage in remineralization solution (≥ 1 h) between cycles. Enamel surface loss (µm) was measured at baseline and every second day (D2, D4, D6) using a 3D-laser-profilometer. Data were analyzed with two-way repeated measures ANOVA and post-hoc comparisons (p < 0.05). All heated groups (100–500 °C) and F significantly increased enamel erosion resistance compared to C (−24.6 ± 1.3 µm,p < 0.05). Furthermore, heating at 300 °C (−8.3 ± 2.7 µm), 400 °C (-5.6 ± 2.4 µm) and 500 °C (−3.2 ± 2.4 µm) resulted in significantly greater erosion resistance than F (−12.3 ± 2.3 µm, p = 0.02/ < 0.01), with 400 °C and 500 °C reducing enamel surface loss by 77 and 87%, respectively. Controlled heating significantly increased enamel erosion resistance, with 400 °C and 500 °C showing the highest protection. While oven heating is not clinically applicable, these findings contribute to understanding of CO₂ laser-induced erosion resistance. The significant increase in enamel erosion resistance following controlled heating suggests that structural modifications play a key role in erosion prevention. While oven heating provided standardized conditions, future research should explore whether similar protective effects can be achieved with clinically applicable CO₂-laser parameters to optimize non-invasive strategies for enamel preservation.

Authors 10

1. Richard Johannes Wierichs

   University of Bern · University of Bonn · University Hospital Bonn

   Affiliation as printed

   Department of Operative Dentistry and Periodontology, University Hospital Bonn, University of Bonn, Bonn, Germany

   Department of Restorative, Preventive and Pediatric Dentistry, University of Bern, Bern, Switzerland

2. Seyed Ahmad Banihashem Rad

   New York University · University of Tübingen

   Affiliation as printed

   Department of Conservative Dentistry, Periodontology and Endodontology, Faculty of Medicine, University of Tübingen, Tübingen, Germany

   Department of Epidemiology and Health Promotion, New York University College of Dentistry, New York, NY, USA

3. Joel Glöckler

   University of Tübingen

   Affiliation as printed

   Department of Conservative Dentistry, Periodontology and Endodontology, Faculty of Medicine, University of Tübingen, Tübingen, Germany

4. Marin Dean Bilandžić Aachen Institute of Mineral Engineering (GHI) Chair of Glass and Glass-ceramic

   RWTH Aachen University

   Affiliation as printed

   Institute of Mineral Engineering (GHI), Chair of Glass and Glass-Ceramic, RWTH Aachen University, Aachen, Germany

5. Stephanie Assimakopoulos Garófalo

   Universidade de São Paulo · University of Tübingen

   Affiliation as printed

   Department of Conservative Dentistry, Periodontology and Endodontology, Faculty of Medicine, University of Tübingen, Tübingen, Germany

   Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil

6. Gabriella T. Schrotter

   Universidade de São Paulo

   Affiliation as printed

   Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil

7. Samira Helena Niemeyer

   University of Bern

   Affiliation as printed

   Department of Restorative, Preventive and Pediatric Dentistry, University of Bern, Bern, Switzerland

8. Guglielmo Campus

   Saveetha University · Sapienza University of Rome · University of Gothenburg

   Affiliation as printed

   Department of Cariology, Institute of Odontology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden

   Department of Cariology, Saveetha, Dental College and Hospitals, SIMATS, Chennai, India

   Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, Rome, Italy

9. Hendrik Meyer‐Lueckel

   University of Bern

   Affiliation as printed

   Department of Restorative, Preventive and Pediatric Dentistry, University of Bern, Bern, Switzerland

10. Marcella Esteves-Oliveira corresponding

    University of Tübingen

    Affiliation as printed

    Department of Conservative Dentistry, Periodontology and Endodontology, Faculty of Medicine, University of Tübingen, Tübingen, Germany. Marcella.Esteves@med.uni-tuebingen.de