Abstract
In-vitro studies commonly simulate toothbrushing using toothpaste slurries of defined dilution levels. However, a recent in-vivo study indicated dilution levels in patients likely to be higher than those typically used. Therefore, this in-vitro study investigated the effects of toothpastes with different relative abrasivity and different dilution on the abrasive wear of enamel and dentin. 144 bovine enamel and dentin samples were randomly assigned to 12 groups each (n = 12). Samples were brushed according to a standardized protocol with three toothpastes of different relative abrasivity on enamel and dentin at four dilution levels (1:1, 1:2, 1:3, 1:6), using 2.5 N brushing force. Enamel samples were brushed for six hours, dentin samples for 25 min. Abrasive wear was measured profilometrically. Statistical analysis was performed with non-parametric Kruskal–Wallis tests. On enamel, dilution significantly affected abrasive wear within all toothpaste groups (p < 0.001), with wear decreasing as dilution increased. On dentin, the dilution again showed a significant effect within all groups (p < 0.001), though maximum abrasive wear occurred at different dilutions for each toothpaste. Dilution, as proved, significantly influences abrasive wear on enamel and dentin. Further studies are required to define an ideal dilution for in-vitro studies, especially for studies performed on dentin.
Data availability
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
References
Walsh, T., Worthington, H. V., Glenny, A. M., Marinho, V. C. & Jeroncic, A. Fluoride toothpastes of different concentrations for preventing dental caries. Cochrane Database Syst. Rev. 3, Cd007868. https://doi.org/10.1002/14651858.CD007868.pub3 (2019).
Petersson, G. H. & Bratthall, D. The caries decline: A review of reviews. Eur. J. Oral. Sci. 104, 436–443 (1996).
Pitts, N. B. et al. Dental caries. Nat. Rev. Dis. Primers 3, 17030. https://doi.org/10.1038/nrdp.2017.30 (2017).
Marinho, V. C., Higgins, J. P., Sheiham, A. & Logan, S. Fluoride toothpastes for preventing dental caries in children and adolescents. Cochrane Database Syst. Rev. 2003, Cd002278. https://doi.org/10.1002/14651858.Cd002278 (2003).
Grabenstetter, R. J., Broge, R. W., Jackson, F. L. & Radike, A. W. The measurement of the abrasion of human teeth by dentifrice abrasives: A test utilizing radioactive teeth. J. Dent. Res. 37, 1060–1068 (1958).
Philpotts, C. J., Weader, E. & Joiner, A. The measurement in vitro of enamel and dentine wear by toothpastes of different abrasivity. Int. Dent. J. 55, 183–187 (2005).
Franzò, D., Philpotts, C. J., Cox, T. F. & Joiner, A. The effect of toothpaste concentration on enamel and dentine wear in vitro. J. Dent. 38, 974–979 (2010).
Wiegand, A., Kuhn, M., Sener, B., Roos, M. & Attin, T. Abrasion of eroded dentin caused by toothpaste slurries of different abrasivity and toothbrushes of different filament diameter. J. Dent. 37, 480–484 (2009).
Wiegand, A. et al. Impact of toothpaste slurry abrasivity and toothbrush filament stiffness on abrasion of eroded enamel - an in vitro study. Acta Odontol. Scand. 66, 231–235 (2008).
Wiegand, A. & Schlueter, N. The role of oral hygiene: Does toothbrushing harm?. Monogr. Oral. Sci. 25, 215–219 (2014).
Addy, M. & Hunter, M. L. Can tooth brushing damage your health? Effects on oral and dental tissues. Int. Dent. J. 53, 177–186 (2003).
Gonzalez-Cabezas, C., Hara, A. T., Hefferren, J. & Lippert, F. Abrasivity testing of dentifrices - challenges and current state of the art. Monogr. Oral Sci. 23, 100–107 (2013).
Hamza, B., Attin, T., Cucuzza, C., Gubler, A. & Wegehaupt, F. J. Rda and rea values of commercially available toothpastes utilising diamond powder and traditional abrasives. Oral Health Prev. Dent. 18, 807–814 (2020).
Lippert, F. An introduction to toothpaste - its purpose, history and ingredients. Monogr. Oral Sci. 23, 1–14 (2013).
Enax, J. & Epple, M. Die charakterisierung von putzkörpern in zahnpasten. Dtsch Zahnärztl Z 73, 100–108 (2018).
Hamza, B., Tanner, M., Attin, T. & Wegehaupt, F. J. Dentin abrasivity and cleaning efficacy of novel/alternative toothpastes. Oral Health Prev. Dent. 18, 713–718 (2020).
Hamza, B., Abdulahad, A., Attin, T. & Wegehaupt, F. J. Diamond particles in toothpastes: In-vitro effect on the abrasive enamel wear. BMC Oral Health 22, 248 (2022).
Hamza, B., Uka, E., Körner, P., Attin, T. & Wegehaupt, F. J. Effect of a sonic toothbrush on the abrasive dentine wear using toothpastes with different abrasivity values. Int. J. Dent. Hyg. 19, 407–412 (2021).
Dobler, L., Hamza, B., Attin, T. & Wegehaupt, F. J. Abrasive enamel and dentin wear resulting from brushing with toothpastes with highly discrepant relative enamel abrasivity (rea) and relative dentin abrasivity (rda) values. Oral Health Prev. Dent. 21, 41–48 (2023).
Körner, P., Inauen, D. S., Attin, T. & Wegehaupt, F. J. Erosive/abrasive enamel wear while using a combination of anti-erosive toothbrush/-paste. Oral Health Prev. Dent. 18, 53–60 (2020).
Wegehaupt, F. J., Hoegger, V. G. M. & Attin, T. Abrasion of eroded and sound enamel by a dentifrice containing diamond abrasive particles. Swiss Dent. J. 127, 634–639 (2017).
Lima, L. C. et al. Role of desensitizing/whitening dentifrices in enamel wear. J. Dent. 99, 103390 (2020).
Vertuan, M., de Souza, B. M., Machado, P. F., Mosquim, V. & Magalhães, A. C. The effect of commercial whitening toothpastes on erosive dentin wear in vitro. Arch. Oral Biol. 109, 104580 (2020).
Simões, A. et al. Do commercial whitening dentifrices increase enamel erosive tooth wear?. J. Appl. Oral Sci. 28, e20190163. https://doi.org/10.1590/1678-7757-2019-0163 (2020).
Wiegand, A., Burkhard, J. P., Eggmann, F. & Attin, T. Brushing force of manual and sonic toothbrushes affects dental hard tissue abrasion. Clin. Oral Investig. 17, 815–822 (2013).
Turssi, C. P., Messias, D. C., Hara, A. T., Hughes, N. & Garcia-Godoy, F. Brushing abrasion of dentin: Effect of diluent and dilution rate of toothpaste. Am. J. Dent. 23, 247–250 (2010).
Tawakoli, P. N., Becker, K. & Attin, T. Abrasive effects of diamond dentifrices on dentine and enamel. Swiss. Dent. J. 128, 14–19 (2018).
Fita, K. & Kaczmarek, U. The impact of selected fluoridated toothpastes on dental erosion in profilometric measurement. Adv. Clin. Exp. Med. 25, 327–333 (2016).
Duke, S. A. & Forward, G. C. The conditions occurring in vivo when brushing with toothpastes. Br. Dent. J. 152, 52–54 (1982).
Manly, R. S. & Schickner, F. Factors influencing tests on the abrasion of dentin by brushing with dentifrices. J. Dent. Res. 23, 59–72 (1944).
Pulfer, A. M., Attin, T. & Wegehaupt, F. J. Salivary flow rate during toothbrushing. Oral Health Prev. Dent. 20, 465–474 (2022).
Klimek, J., Hellwig, E. & Ahrens, G. Fluoride taken up by plaque, by the underlying enamel and by clean enamel from three fluoride compounds in vitro. Caries Res. 16, 156–161 (1982).
Attin, T., Becker, K., Roos, M., Attin, R. & Paqué, F. Impact of storage conditions on profilometry of eroded dental hard tissue. Clin. Oral Invest. 13, 473–478 (2009).
Team, R. C. R: A language and environment for statistical computing https://www.r-project.org (2020).
Wickham, H. et al. Welcome to the tidyverse. J. Open Sour. Softw. 4, 1686 (2019).
Pohlert, T. The pairwise multiple comparison of mean ranks package (pmcmr). R package https://CRAN.R-project.org/package=PMCMR (2014).
Pohlert, T. Pmcmrplus: Calculate pairwise multiple comparisons of mean rank sums extended. R package version 1.9.100. 2018 https://CRAN.R-project.org/package=PMCMRplus. (2023).
Arango-Santander, S., Montoya, C., Pelaez-Vargas, A. & Ossa, E. A. Chemical, structural and mechanical characterization of bovine enamel. Arch. Oral Biol. 109, 104573. https://doi.org/10.1016/j.archoralbio.2019.104573 (2020).
Teruel Jde, D., Alcolea, A., Hernández, A. & Ruiz, A. J. Comparison of chemical composition of enamel and dentine in human, bovine, porcine and ovine teeth. Arch. Oral Biol. 60, 768–775 (2015).
Wegehaupt, F. J., Widmer, R. & Attin, T. Is bovine dentine an appropriate substitute in abrasion studies?. Clin. Oral Investig. 14, 201–205 (2010).
Yassen, G. H., Platt, J. A. & Hara, A. T. Bovine teeth as substitute for human teeth in dental research: A review of literature. J. Oral Sci. 53, 273–282 (2011).
Tawakoli, P. N., Sener, B. & Attin, T. Mechanical effects of different swiss market-leading dentifrices on dentin. Swiss Dent. J. 125, 1210–1219 (2015).
Wegehaupt, F., Gries, D., Wiegand, A. & Attin, T. Is bovine dentine an appropriate substitute for human dentine in erosion/abrasion tests?. J. Oral Rehabil. 35, 390–394 (2008).
Attin, T., Wegehaupt, F., Gries, D. & Wiegand, A. The potential of deciduous and permanent bovine enamel as substitute for deciduous and permanent human enamel: Erosion-abrasion experiments. J. Dent. 35, 773–777 (2007).
Wiegand, A. & Attin, T. Design of erosion/abrasion studies – insights and rational concepts. Caries Res. 45(Suppl 1), 53–59 (2011).
Imfeld, T. Mechanische wirkung von in der schweiz marktführenden zahnpasten auf dentin. Schweiz. Monatsschr. Zahnmed. 108, 54–214 (1998).
Ganss, C., Schlueter, N., Preiss, S. & Klimek, J. Tooth brushing habits in uninstructed adults–frequency, technique, duration and force. Clin. Oral Investig. 13, 203–208 (2009).
Chun, K., Choi, H. & Lee, J. Comparison of mechanical property and role between enamel and dentin in the human teeth. J. Dent. Biomech. 5, 1758736014520809 https://doi.org/10.1177/1758736014520809 (2014).
Hamza, B. et al. Effect of brushing force on the abrasive dentin wear using slurries with different abrasivity values. Int. J. Dent. Hyg. 21, 172–177 (2023).
Schneiderman, E., Colón, E., White, D. J. & St John, S. A profilometry-based dentifrice abrasion method for v8 brushing machines part ii: Comparison of rda-pe and radiotracer rda measures. J. Clin. Dent. 26, 61–65 (2015).
White, D. J., Schneiderman, E., St Colón, E. & John, S. A profilometry-based dentifrice abrasion method for v8 brushing machines. Part i: Introduction to rda-pe. J. Clin. Dent. 26, 1–6 (2015).
Prencipe, M., Vandeven, M., Feldman, B. N. & Schemehorn, B. R. A comparative study of laboratory dentifrice abrasion measuring methods. J. Clin. Dent. 27, 105–109 (2016).
Zimmerman, B. et al. Alteration of dentin-enamel mechanical properties due to dental whitening treatments. J. Mech. Behav. Biomed. Mater. 3, 339–346 (2010).
Xu, C. & Wang, Y. Chemical composition and structure of peritubular and intertubular human dentine revisited. Arch. Oral Biol. 57, 383–391 (2012).
Montoya, C., Arango-Santander, S., Peláez-Vargas, A., Arola, D. & Ossa, E. A. Effect of aging on the microstructure, hardness and chemical composition of dentin. Arch. Oral Biol. 60, 1811–1820 (2015).
Arola, D. et al. Microstructure and mechanical behavior of radicular and coronal dentin. Endod. Topics 20, 30–51 (2009).
Gil-Bona, A. & Bidlack, F. B. Tooth enamel and its dynamic protein matrix. Int. J. Mol. Sci. 21, 4458. https://doi.org/10.3390/ijms21124458 (2020).
Arola, D. D., Gao, S., Zhang, H. & Masri, R. The tooth: Its structure and properties. Dent. Clin. North Am. 61, 651–668 (2017).
Mjör, I. A. & Nordahl, I. The density and branching of dentinal tubules in human teeth. Arch. Oral Biol. 41, 401–412 (1996).
Schilke, R., Lisson, J. A., Bauss, O. & Geurtsen, W. Comparison of the number and diameter of dentinal tubules in human and bovine dentine by scanning electron microscopic investigation. Arch. Oral Biol. 45, 355–361 (2000).
Camargo, C. H. et al. Topographical, diametral, and quantitative analysis of dentin tubules in the root canals of human and bovine teeth. J. Endod. 33, 422–426 (2007).
Acknowledgements
This study was conducted as the doctoral thesis of med. dent. Francesco Fragapane and performed at the Center for Dental Medicine, Clinic of Conservative and Preventive Dentistry at the University of Zürich, Switzerland, under the supervision of Dr. Moritz Tanner, Prof. Dr. Florian J. Wegehaupt and Prof. Dr. Dr. h.c. Thomas Attin. The toothbrushes used in this study were provided by Esro AG, Kilchberg, Switzerland. The company had no influence on any part of this study.
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F.F. and M.T. wrote the manuscript; F.F. performed the experiment; T.A. and F.W. conceived and designed the experiment and critical evaluation of the manuscript. All authors reviewed the manuscript.
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The bovine teeth used in this study were obtained from the jaws of animals slaughtered for human consumption. As a result, these teeth are considered slaughter waste, and its use is not covered by the Animal Welfare Act. Therefore, there was no requirement for ethics committee clearance in order to conduce the experiment.
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Fragapane, F., Tanner, M., Attin, T. et al. Effect of different dilution levels of toothpastes on the abrasive wear on enamel and dentin in in-vitro studies. Sci Rep (2026). https://doi.org/10.1038/s41598-026-35388-7
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DOI: https://doi.org/10.1038/s41598-026-35388-7
