Enamel and dentin bond strength, interfacial ultramorphology and fluoride ion release of self-etching adhesives during a pH-cycling regime

[Clinical and laboratory evaluation of the Elgydium Protection caries toothpaste effectiveness in patients with high intensity of dental caries]

The aim of the work was to evaluate the effectiveness of rehabilitation after the complete elimination of carious cavities in patients with dentin caries according to clinical and laboratory indicators when using the ELGYDIUM Protection caries toothpaste for cleaning teeth for 6 months. 29 patients with high intensity of dental caries were examined and received treatment. Depending on the organization of daily hygienic measures after treatment the patients were divided into two groups. The main group included 14 patients who used Elgydium Protection caries paste ('Pierre Fabre Medicament', France) for brushing their teeth twice a day for 6 months. The control group included 15 patients who used toothpastes with fluoride of the first generation. All patients underwent clinical dental examination with the determination of the DMFT index and the amount of soft dental plaque according to the Silness-Lohe index, as well as in the gingival fluid bacteriological examination of cariogenic microbiota, determination of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α) and an immunoassay for anti-inflammatory peptides α-defensins 1-3. Effective change in the concentration of antimicrobial peptides α-defensins 1-3 and TNF-α after treatment along with successful eradication of cariogenic bacteria from carious cavities, the absence of recurrent dental caries in the main group compared with the control group proved the successful anti-caries action of long-term use of fluorenol capable of forming a uniform film on the surface of the tooth in the presence of silyglycol. The protective film helps to increase the resistance of the tooth to demineralization and prevents plaque formation. Thus, the study results proved the effectiveness of ELGYDIUM Protection caries toothpaste used for 6 months for the reduction of caries.

Degradation of resin-dentine bond of different adhesive systems to primary and permanent dentine

AIM

To evaluate the water storage degradation of resin-dentine bonds of different adhesive systems to primary and permanent human dentine.

METHODS

Flat occlusal human dentine surfaces of 15 primary molars and 15 permanent molars were randomly assigned according to adhesive systems: Adper Single Bond 2; Clearfil SE Bond and One Up Bond F Plus. After bonding procedures, the adhesives were applied according to the manufacturers' instructions and composite resin blocks were built. Restored teeth were sectioned rendering rectangular sticks (RS) (0.4 mm²). The RS were submitted to microtensile bond strength (µTBS) test according to the water storage time: 24 h, 1-year, and 2-years. Mean µTBS values were analysed by three-way analysis of variance (mixed design) and Tukey post hoc test (α = 0.05). The failure mode was analysed at 400× magnification.

RESULTS

All three factors isolated showed significant influences on µTBS, as did the cross-product interactions between material vs. storage time (p = 0.01) and substrate vs. storage time (p = 0.002). Bond strength means to primary dentine were lower than to permanent dentine (34.7 ± 10.1 and 45.8 ± 12.9 mPa, respectively) after 2-years of water storage. The one-step self-etch adhesive (One Up Bond F Plus) showed less stable bond strength after 2-years of water storage.

CONCLUSION

The resin-dentine bond of primary teeth was more prone to degradation over time compared to permanent dentine.