{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T10:59:17Z","timestamp":1785495557582,"version":"3.56.0"},"reference-count":35,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T00:00:00Z","timestamp":1785024000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The durability of dental restorations against erosive and staining challenges is crucial for long-term clinical success. Therefore, this in vitro study aimed to investigate the combined effects of sequential simulated gastric acid exposure, coffee immersion, and different cleaning procedures on the surface roughness and color stability of four contemporary flowable resin composites with different filler and matrix characteristics. Ninety-six disk-shaped specimens were fabricated from four resin composites: Omnichroma Flow, G-\u00e6nial Universal Injectable, Universal Flo, and EverX Flow. Baseline surface roughness and color coordinates were recorded. Specimens were immersed in 0.06 M hydrochloric acid for 48 h to simulate gastric acid exposure and subsequently immersed in coffee solution for 24 h to simulate staining. Color measurements were performed at baseline, after sequential gastric acid\u2013coffee exposure, and after cleaning procedures. \u0394E0 was calculated between baseline and post-exposure values, whereas \u0394E1 was calculated between post-exposure and post-cleaning values. Specimens were then allocated to three cleaning subgroups: toothbrushing (BR), water flosser (WF) and mouthrinse (MR). Final surface roughness and color changes were evaluated. Data were analyzed using mixed and factorial ANOVA tests. Sequential gastric acid\u2013coffee exposure significantly increased surface roughness in all materials. Omnichroma Flow showed the lowest roughness values, whereas G-\u00e6nial Universal Injectable demonstrated the highest post-treatment roughness, particularly after toothbrushing. Toothbrushing generally caused greater roughness increases than other cleaning procedures. Material type significantly affected color stability, with Universal Flo showing the greatest discoloration and Omnichroma Flow the lowest color change. Surface roughness and color stability were significantly influenced by sequential gastric acid\u2013coffee exposure and cleaning procedures in a material-dependent manner.<\/jats:p>","DOI":"10.3390\/polym18151827","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T01:26:23Z","timestamp":1785115583000},"page":"1827","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Combined Effects of Simulated Gastric Acid, Coffee Immersion, and Cleaning Procedures on the Surface Topography and Optical Properties of Flowable Resin Composites"],"prefix":"10.3390","volume":"18","author":[{"given":"Lena","family":"Bal","sequence":"first","affiliation":[{"name":"Department of Restorative Dentistry, Faculty of Dentistry, Ankara Medipol University, 06570 Ankara, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cang\u00fcl","family":"Keskin","sequence":"additional","affiliation":[{"name":"Department of Endodontics, Faculty of Dentistry, 19 May\u0131s University, 55270 Ankara, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G\u00f6k\u00e7e Naz","family":"C\u00f6mert","sequence":"additional","affiliation":[{"name":"Department of Prosthodontic Dentistry, Faculty of Dentistry, Ankara Medipol University, 06570 Ankara, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-4115-6021","authenticated-orcid":false,"given":"Osman Fatih","family":"Ayd\u0131n","sequence":"additional","affiliation":[{"name":"Department of Restorative Dentistry, Faculty of Dentistry, Ankara Medipol University, 06570 Ankara, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fatma","family":"\u00d6zt\u00fcrk Tun\u00e7el","sequence":"additional","affiliation":[{"name":"Department of Restorative Dentistry, Faculty of Dentistry, Health Sciences University, 06018 Ankara, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1016\/j.jdent.2017.06.002","article-title":"Repair may increase survival of direct posterior restorations\u2013A practice based study","volume":"64","author":"Casagrande","year":"2017","journal-title":"J. Dent."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tzimas, K., Pappa, E., Fostiropoulou, M., Papazoglou, E., and Rahiotis, C. (2025). Highly filled flowable composite resins as sole restorative materials: A systematic review. Materials, 18.","DOI":"10.20944\/preprints202503.1030.v1"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Yenidunya, O.G., Misilli, T., and Yilmaz, E. (2025). Gastric acid challenge: Mechanical proficiency and surface gloss of tooth-colored restorative materials. BMC Oral Health, 25.","DOI":"10.1186\/s12903-025-05988-2"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"424","DOI":"10.1111\/jopr.12420","article-title":"Effects of simulated gastric juice on CAD\/CAM resin composites\u2014Morphological and mechanical evaluations","volume":"26","author":"Backer","year":"2017","journal-title":"J. Prosthodont."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1007\/s44445-025-00095-y","article-title":"Assessing the durability of dental composites in GERD-like condition: A study of color stability and hardness","volume":"37","author":"AlQahtani","year":"2025","journal-title":"Saudi Dent. J."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1002\/mawe.201900029","article-title":"Factors influencing mechanical and wear performance of dental composite: A review","volume":"51","author":"Kumar","year":"2020","journal-title":"Mater. Werkst."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e18742106348736","DOI":"10.2174\/0118742106348736241010105828","article-title":"Influence of acidic drinks and brushing on microhardness of restorative resin materials","volume":"18","author":"Baroudi","year":"2024","journal-title":"Open Dent. J."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Beltrami, R., Colombo, M., Bitonti, G., Chiesa, M., Poggio, C., and Pietrocola, G. (2022). Restorative materials exposed to acid challenge: Influence of temperature on in vitro weight loss. Biomimetics, 7.","DOI":"10.3390\/biomimetics7010030"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Lussi, A., and Carvalho, T.S. (2014). Erosive Tooth Wear: A Multifactorial Condition of Growing Concern and Increasing Knowledge, Karger.","DOI":"10.1159\/000360380"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Nezir, M., Alt\u0131n\u0131\u015f\u0131k, H., \u00d6zyurt, E., Bayar, N., and Dindar, M.B. (2025). The effects of mechanical and chemical degradation on the surface roughness, gloss, and color stability of bulk-fill resin composites. BMC Oral Health, 25.","DOI":"10.1186\/s12903-025-07151-3"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"105606","DOI":"10.1016\/j.jmbbm.2022.105606","article-title":"Effects of gastric acid and mechanical toothbrushing in CAD-CAM restorative materials: Mechanical properties, surface topography, and biofilm adhesion","volume":"138","author":"Kury","year":"2023","journal-title":"J. Mech. Behav. Biomed. Mater."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"105031","DOI":"10.1016\/j.jdent.2024.105031","article-title":"The chemical and optical stability evaluation of injectable restorative materials under wet challenge","volume":"146","author":"Bai","year":"2024","journal-title":"J. Dent."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"\u00d6mero\u011flu, M.K., and Hekimo\u011flu, H.C. (2025). Evaluation of colour stability, water sorption and solubility of no-cap flowable bulk fill resin composites. BMC Oral Health, 25.","DOI":"10.1186\/s12903-025-05902-w"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/j.jdent.2016.05.008","article-title":"Posterior bulk-filled resin composite restorations: A 5-year randomized controlled clinical study","volume":"51","author":"Pallesen","year":"2016","journal-title":"J. Dent."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1214","DOI":"10.1016\/j.dental.2015.07.005","article-title":"Anterior composite restorations: A systematic review on long-term survival and reasons for failure","volume":"31","author":"Demarco","year":"2015","journal-title":"Dent. Mater."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1111\/jerd.13301","article-title":"Effect of acidic media on surface characteristics of highly filled flowable resin-based composites: An in vitro study","volume":"37","author":"Blatz","year":"2025","journal-title":"J. Esthet. Restor. Dent."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"567.e1","DOI":"10.1016\/j.prosdent.2019.08.022","article-title":"Effect of acidic pH on surface roughness of esthetic dental materials","volume":"122","author":"Alnasser","year":"2019","journal-title":"J. Prosthet. Dent."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"587","DOI":"10.14219\/jada.archive.2004.0246","article-title":"The effect of surface finishing and storage solutions on the color stability of resin-based composites","volume":"135","author":"Patel","year":"2004","journal-title":"J. Am. Dent. Assoc."},{"key":"ref_19","first-page":"250","article-title":"Effects of polishing systems and storage media on color stability and surface roughness of bulk-fill restorative composites","volume":"34","author":"Hatirli","year":"2021","journal-title":"Am. J. Dent."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1445","DOI":"10.1016\/j.dental.2015.09.010","article-title":"Impact of gastric acidic challenge on surface topography and optical properties of monolithic zirconia","volume":"31","author":"Sulaiman","year":"2015","journal-title":"Dent. Mater."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1159\/000325946","article-title":"Design of erosion\/abrasion studies\u2014Insights and rational concepts","volume":"45","author":"Wiegand","year":"2011","journal-title":"Caries Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"e169","DOI":"10.4317\/jced.56153","article-title":"Effect of water-jet flossing on surface roughness and color stability of dental resin-based composites","volume":"12","author":"Alharbi","year":"2020","journal-title":"J. Clin. Exp. Dent."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Bal, L., and \u00d6zt\u00fcrk, C. (2025). The effect of UV aging on the color stability and translucency of luting agents cemented to different CAD\/CAM materials. BMC Oral Health, 25.","DOI":"10.1186\/s12903-025-06001-6"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"54","DOI":"10.17567\/currresdentsci.1514578","article-title":"Effect of gastric acid on the surface properties of different composite resin restorative materials: Scanning electron microscope SEM evaluation","volume":"35","author":"Alp","year":"2025","journal-title":"Curr. Res. Dent. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Szczesio-Wlodarczyk, A., Sokolowski, J., Kleczewska, J., and Bociong, K. (2020). Ageing of dental composites based on methacrylate resins\u2014A critical review of the causes and method of assessment. Polymers, 12.","DOI":"10.3390\/polym12040882"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e57","DOI":"10.1016\/j.jdent.2011.12.017","article-title":"Intrinsic and extrinsic discoloration of dimethacrylate and silorane based composites","volume":"40","author":"Barutcigil","year":"2012","journal-title":"J. Dent."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1016\/S0109-5641(97)80038-3","article-title":"Comparison of surface roughness of oral hard materials to the threshold surface roughness for bacterial plaque retention: A review of the literature","volume":"13","author":"Bollenl","year":"1997","journal-title":"Dent. Mater."},{"key":"ref_28","first-page":"2202211","article-title":"Deterioration of direct restorative materials under erosive conditions with impact of abrasion and attrition in vitro","volume":"10","author":"Mulic","year":"2023","journal-title":"Biomater. Investig. Dent."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1007\/s00784-014-1262-x","article-title":"Effect of different curing protocols on the mechanical properties of low-viscosity bulk-fill composites","volume":"19","author":"Ilie","year":"2015","journal-title":"Clin. Oral Investig."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Santana, I.C., de Oliveira, S.S., Botelho, K.P., de Oliveira Rigotti, R.L., Gl\u00f3ria, J.C.R., Botelho, A.M., Douglas-de-Oliveira, D.W., and Tavano, K.T.A. (2025). Evaluation of the roughness, color match, and color stability of two monochromatic composite resins: A randomized controlled laboratory study. BMC Oral Health, 25.","DOI":"10.1186\/s12903-025-05681-4"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1038\/s41368-023-00226-3","article-title":"Micromechanical interlocking structure at the filler\/resin interface for dental composites: A review","volume":"15","author":"Zhang","year":"2023","journal-title":"Int. J. Oral Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1007\/s00784-009-0258-4","article-title":"Investigations on mechanical behaviour of dental composites","volume":"13","author":"Ilie","year":"2009","journal-title":"Clin. Oral Investig."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1007\/s10266-018-0405-y","article-title":"Characterization of a new fiber-reinforced flowable composite","volume":"107","author":"Lassila","year":"2019","journal-title":"Odontology"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"S1","DOI":"10.1111\/jerd.12149","article-title":"Color difference thresholds in dentistry","volume":"27","author":"Paravina","year":"2015","journal-title":"J. Esthet. Restor. Dent."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1002\/jbm.b.30252","article-title":"Elution study of unreacted Bis-GMA, TEGDMA, UDMA, and Bis-EMA from light-cured dental resins and resin composites using HPLC","volume":"74","author":"Sideridou","year":"2005","journal-title":"J. Biomed. Mater. Res. B Appl. Biomater."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/15\/1827\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T10:15:46Z","timestamp":1785492946000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/15\/1827"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,26]]},"references-count":35,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["polym18151827"],"URL":"https:\/\/doi.org\/10.3390\/polym18151827","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,26]]}}}