Objectives: The management of white-spot lesions remains a challenge, especially during and after fixed orthodontic treatment. The aim of this in vitro study was to evaluate the efficacy of the newly introduced self-assembling peptide P11-4 (Curodont™) for regenerating demineralized tooth tissue on smooth surfaces. Another aim was to evaluate whether the DIAGNOdent (DD) and VistaProof (VP) fluorescence systems are suitable for differentiating between demineralized and remineralized enamel.
Materials and methods: A total of 40 sound samples (buccal surfaces) of extracted human posterior teeth were artificially demineralized. The samples were examined visually as well as via DD and VP. Curodont was applied to 30 samples which were then stored in a remineralizing agent (test group). In control group 1, Curodont was applied to 5 samples which were then stored in water. Control group 2 consisted of 5 samples stored in the remineralizing agent only. Sample surfaces were examined visually and by means of DD and VP after 1 week (t1), 8 weeks (t2), and 12 weeks (t3). All fluorescence measurements were taken twice. Sample surfaces were viewed using a scanning electron microscope (SEM). Statistical analysis was conducted using the IBM SPSS® Statistics and MedCalc® programs. The fluorescence measurements' reproducibility was calculated using the intraclass correlation coefficient (ICC). A χ(2) test was applied to detect any significant differences between the fluorescence measurements of the test and control groups at each examination. Receiver operating characteristic (ROC) curves of DD and VP were constructed and areas under the ROC curve (AUC) were compared (α = 0.05) between the two fluorescence devices.
Results: Reproducibility of DD was moderate at t3, while the ICC values were high for all other measurements. Significant differences between the fluorescence measurements at t2 and t3 between the test and control groups (p < 0.001 for DD and VP, respectively) were observed. The performance (AUC) of DD was significantly higher than VP (visual inspection: p = 0.017; SEM: p = 0.030). At t3, all test-group samples displayed a shinier surface than the surface after demineralization. The SEM images of 28 test-group samples exhibited extensive signs of remineralized enamel.
Conclusion: Based on visual inspection, Curodont proved to be efficacious in all samples. The SEM images revealed large areas of remineralized enamel surface in 93 % of the samples. Both fluorescence systems enabled the detection of differences between the measurements of the test and control groups after 8 and 12 weeks.