Effect of Conventional Mouthrinses on Initial Bioadhesion to Enamel and Dentin in situ

Abstract

Aim: The study aimed to investigate the effect of a customary fluoride solution, containing sodium fluoride and amine fluoride, on initial biofilm formation on enamel and dentin in situ compared directly to chlorhexidine. Methods: Bovine enamel and dentin specimens were mounted on maxillary splints carried by 9 subjects. After 1 min of pellicle formation, rinses with tap water (control), chlorhexidine (meridol med CHX 0.2%, GABA) and a fluoride mouthrinse (elmex, GABA) were performed for 1 min. Subsequently, the slabs were carried for another 8 h. The adherent bacteria were determined by DAPI staining, live-dead staining and determination of colony-forming units after desorption; glucan formation was visualized with concanavalin A. Additionally, energy-dispersive X-ray spectroscopy (EDX) analysis of the in situ biofilm layers was conducted, and contact angle measurements were performed. Statistical evaluation was performed by means of the Kruskal-Wallis test followed by the Mann-Whitney U test (p < 0.05). Results: In the control group, significantly higher amounts of adherent bacteria were detected on dentin (4.8 × 10⁶ ± 5.4 × 10⁶ bacteria/cm²) than on enamel (1.2 × 10⁶ ± 1.5 × 10⁶ bacteria/cm², DAPI). Chlorhexidine significantly reduced the amount of adherent bacteria (dentin: 2.8 × 10⁵ ± 3.4 × 10⁵ bacteria/cm²; enamel: 4.2 × 10⁵ ± 8.7 × 10⁵ bacteria/cm²). Rinses with the fluoride solution also significantly reduced bacterial adherence to dentin (8.1 × 10⁵ ± 1.5 × 10⁶ bacteria/cm²). Fluoride could not be detected by EDX analysis of the biofilms. Fluoride mouthrinsing did not influence the wettability of the pellicle-covered enamel surface. Conclusion: In addition to the reduction of demineralization and antibacterial effects, fluorides inhibit initial biofilm formation on dental hard tissues considerably, especially on dentin.

Efficacy of pastes containing CPP-ACP and CPP-ACFP in patients with Sjögren’s syndrome

“…Therefore, it can be presumed that fluorine ions were not possible to detect although they might have been present at the surface of enamel. In an in situ study, Hannig et al [41] reported that no accumulation of fluoride was traceable on enamel surface immediately after application of fluoride mouthrinse. Having in mind the wellknown model of fluoride effect by the formation of a calcium fluoride layer, authors considered that fluoride layers were rapidly covered and masked by pellicle structures, which made them not detectable by the EDS analysis.…”

Effect of CPP/ACP on Initial Bioadhesion to Enamel and DentinIn Situ

“…Our study revealed no antibacterial and antiadherent effects for CPP/ACP. The bioadhesion processes were determined in situ , considering that in vivo and in vitro conditions differ considerably [25]. The methodical approach, including bovine enamel and dentin specimens fixed to individual upper jaw splints, has already been used in previous studies [20, 25].…”

Commercial antimicrobials mouthrinses on caries and periodontitis-related biofilm control: a review of literature

“…Hannig et al [29] compared the effect of fluoride solution (100 ppm F as AmF and 150 ppm F as NaF) to 0.2% CHX (positive control) on biofilm adherence to enamel and dentin in situ after 8 h of 1 min-rinse. The bacterial viability and CFU for total microorganism were determined.…”