Organic volume and permeability variations in the surface layer of artificial and natural enamel carious lesions

• Published in: Archives of oral biology Vol. 148; p. 105645
• Main Authors: de Holanda Ferreira, Danilo Augusto, Rolim de Abreu, Nathalie Murielly, Meira, Kássia Regina Simões, de Sousa, Frederico Barbosa
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2023
• Subjects: Demineralization; Dental Caries - pathology; Dental Enamel - pathology; Enamel caries; Histopathology; Humans; Minerals; Permeability; Tooth Remineralization; Enamel caries; Histopathology; Demineralization
• ISSN: 0003-9969; 1879-1506
• DOI: 10.1016/j.archoralbio.2023.105645

Test the hypothesis the type of enamel caries (natural, artificial induced by gel, and artificial induced by acid solutions) affect the organic volume and the permeability of the surface layer in enamel caries lesions. Artificial enamel caries, induced by either acidic solution (organic-poor; Group 1) or acidic gel (organic-rich; Group 2), and natural non-cavitated inactive approximal enamel caries lesions (NEC; Group 3) were obtained, from which longitudinal ground sections were prepared. Measurements of the mineral (Vmin) (by microradiography), and water (α) and organic (β) volumes (by optical birefringence) were obtained at three points in the surface layer (n = 30/group). The main outcomes were the ratio between experimental β by predicted β (β Ratio) and the ratio between experimental and predicted permeabilities (αd Ratio). β Ratio in Group 1 was lower than in Groups 2 (Cohen’s d: −1.81; 95% CI:−1.45,−2.32; p < 0.001) and 3 (Cohen’s d: −0.71; 95% CI:−0.27,−1.18; p = 0.004), and Group 2 surpassed Group 3 (Cohen’s d: 0.49; 95% CI:0.07,0.94; p = 0.03). αd Ratio in Group 1 was higher than in Groups 2 (Cohen’s d: 1.86; 95% CI:1.49,2.33; p < 0.001) and 3 (Cohen’s d: 0.60; 95% CI:0.18,1.14; p = 0.01), and Group 3 surpassed Group 2 (Cohen’s d: 0.61; 95% CI:0.23,1.07; p = 0.01). The highest organic volume and the lowest permeability occurred at the surface layer of gel-induced artificial enamel caries lesions, which should be preferred in in vitro studies on de- and remineralization and resin infiltration. •Effect of enamel caries lesion type on organic volume and permeability was tested.•The surface layer in three lesion types was investigated.•Lesion types: natural (NL) and artificial (formed by acid solution, SL, or gel, GL).•Organic volume gradient: SL<NL<GL.•Permeability gradient: GL<NL<SL.