Influence of periodic polyphenol treatment on the anti-erosive potential of the acquired enamel pellicle-A qualitative exploratory study.

Objective: The aim of the present study was to investigate the impact of periodic polyphenol treatment on the ultrastructure and anti-erosive potential of an in-situ formed pellicle.

Methods: Subjects wore intraoral appliances with buccally and palatally fixed bovine enamel specimens. During 6 h of intraoral pellicle formation, 100 ml black tea or tannic acid was applied ex-vivo every 25 min for 5 min.

Influence of periodic milk or cream treatment on the anti-erosive potential of the acquired enamel pellicle.

Objective: The purpose of the present study was to assess the anti-erosive potential of the acquired enamel pellicle formed in situ under the influence of periodic milk or cream treatment.

Methods: The pellicle was formed on bovine enamel specimens in the oral cavity at buccal and palatal sites of upper molars in 6 subjects, using removable acrylic splints. During 6-h of intraoral exposure, splints were removed from the oral cavity every 25 min, treated with milk or cream for 5 min, and subsequently re-inserted into the oral cavity.

The effect of polyphenol-containing solutions on in situ biofilm formation on enamel and dentin.

Objectives: To investigate the effects of Chinese gallnut extracts and pure tannic acid on in situ biofilm formation on enamel and dentin samples over 24 h.

Methods: Bovine enamel and dentin samples were buccally fixed on maxillary splints. Six volunteers wore the splints for 24 h, and rinsed their mouths with tap water (control), 1% tannic acid- and 1% Chinese gallnut extracts-containing solution twice a day, 3 min after the splints were placed in the mouth and before night sleep.

Comprehensive measurements of salivary pellicle thickness formed at different intraoral sites on Si wafers and bovine enamel.

The salivary pellicle is a thin acellular film formed on orally exposed surfaces by adsorption of macromolecules from the oral fluids and serves as a protective layer in the maintenance of oral health. Pellicle thickness measurements are a central tool helping to understand how exogenous manipulations may influence pellicle formation. This is of particular importance for the investigation of new preventive and therapeutic approaches.

Effect of Tannic Acid on the Protective Properties of the in situ Formed Pellicle.

Objectives: In the present in situ/ex vivo study the impact of tannic acid on the erosion-protective properties of the enamel pellicle was tested. Additionally, the antiadherent and antibacterial effects of tannic acid were evaluated.

Methods: The pellicle was formed in situ on bovine enamel samples fixed on individual splints worn by 6 subjects.

Effect of Inula viscosa on the pellicle's protective properties and initial bioadhesion in-situ.

Objectives: The present in situ study investigated the effect of Inula viscosa tea on the pellicle's acid protective properties and on initial oral biofilm formation.

Design: Biofilm formation was performed on bovine enamel slabs on individual maxillary splints. Following 1min of pellicle formation, eight subjects rinsed for 10min with Inula viscosa tea and the splints remained for 8h intraorally.

Enzymes in the in-situ pellicle of children with different caries activity.

The present study investigated, for the first time, enzymes in the in-situ pellicle of children. Furthermore, it was purposed to detect glucosyltransferase (GTF) isoforms in each child's pellicle. Twenty-four children (5-9 yr of age) participated in the study.

Protein adhesion on dental surfaces-a combined surface analytical approach.

Protein adsorption is a field of huge interest in a number of application fields. Information on protein adhesion is accessible by a variety of methods. However, the results obtained are significantly influenced by the applied technique.

Visualization of initial bacterial colonization on dentine and enamel in situ.

Bacterial colonization of dentine is of high relevance in cariology, endodontology and periodontology. The aim of the present in situ study was to establish recent methods for visualization and quantification of initial bacterial adherence to dentine in comparison to enamel. For this purpose, bovine enamel and dentine slabs were fixed on buccal sites of individual upper jaw splints worn by 6 subjects for 30min, 120min and 360min, respectively.

Targeted immobilisation of lysozyme in the enamel pellicle from different solutions.

Mouthwashes containing protective enzymes are required especially for patients suffering from xerostomia. The present study aimed to investigate the possibilities of modulating the immobilisation of lysozyme in the in situ pellicle layer. In situ formed pellicles were incubated in vitro for 10 min with various enzymatic buffer solutions containing lysozyme and additive enzymes such as transglutaminase or trypsin as well as polyphenolic compounds (cistus tea).

Initial bioadhesion on dental materials as a function of contact time, pH, surface wettability, and isoelectric point.

The adsorption of bovine serum albumin (BSA) on surfaces of dental enamel and of dental materials was investigated by scanning force spectroscopy. This method provides adhesion forces which can be measured as a function of contact time between protein and surface, pH, wettability, and isoelectric point of the surface. Whereas the chosen ceramic and composite materials resemble very well the adhesion on natural enamel, a much stronger adhesion was found for the more hydrophobic surfaces, that is, gold, titanium, poly(methyl methacrylate) (PMMA), and poly(tetrafluoroethylene) (PTFE).

Detection and activity of peroxidase in the in situ formed enamel pellicle.

Aim: Peroxidase is the main salivary antioxidant. The aim of the present study was to detect and to characterise peroxidase in the in situ enamel pellicle.

Methods: Bovine enamel slabs were fixed on maxillary splints and carried by six subjects for different times (3, 30 and 120 min) on buccal and palatal sites.

Effects of dental bleaching on micro- and nano-morphological alterations of the enamel surface.

Purpose: To investigate the effects of dental bleaching on the enamel surface micromorphology using SEM and TEM.

Methods: Fine-polished enamel slabs were randomly divided into eight groups (n = 3). Unbleached specimens served as control (1).

Non-destructive visualisation of protective proteins in the in situ pellicle.

Several salivary anti-microbial and buffering components are part of the acquired in vivo pellicle. The purpose of the present in situ study was to visualise these proteins within the in situ formed pellicle and to investigate their distribution with respect to pellicle formation time and intra-oral localisation. Bovine enamel slabs were fixed on individual splints.

Protective effect of the in situ pellicle on dentin erosion - an ex vivo pilot study.

Aim: The acquired pellicle is well known as an anti-erosive proteinaceous layer on enamel, but its protective properties on dentin have not been investigated in detail until now. The aim of the present ex vivo study was to evaluate the erosive effects on pellicle coated dentin.

Methods: Bovine dentin slabs were exposed to the oral cavity of one subject for 120 min for in situ pellicle formation.

Electron microscopic detection of salivary alpha-amylase in the pellicle formed in situ.

Immunological and biochemical analyses have shown that alpha-amylase is an essential component of the acquired pellicle. After adsorption, this enzyme might act as a receptor for bacterial adherence. However, data indicating that amylase is bound to the pellicle surface in vivo and thus available for adhering bacteria are rare.

Inter-crystallite nanoretention of self-etching adhesives at enamel imaged by transmission electron microscopy.

The purpose of this in vitro study was to analyse the mode of action of self-etching adhesive systems when applied for resin-to-enamel bonding. Transmission electron microscopy was used to investigate the enamel-resin interface after application of non-rinsing self-etching adhesive systems based on phosphoric acid estered methacrylates (Clearfil Liner Bond 2, Clearfil SE Bond, Etch & Prime 3.0 and Resulcin AquaPrime) compared with conventional phosphoric acid etching and bonding (Heliobond).