Reduction of Streptococcus mutans Adherence and Dental Biofilm Formation by Surface Treatment with Phosphorylated Polyethylene Glycol

Abstract

Initial attachment of the cariogenic Streptococcus mutans onto dental enamel is largely promoted by the adsorption of specific salivary proteins on enamel surface. Some phosphorylated salivary proteins were found to reduce S. mutans adhesion by competitively inhibiting the adsorption of S. mutans-binding salivary glycoproteins to hydroxyapatite (HA). The aim of this study was to develop antiadherence compounds for preventing dental biofilm development. We synthesized phosphorylated polyethylene glycol (PEG) derivatives and examined the possibility of surface pretreatment with them for preventing S. mutans adhesion in vitro and dental biofilm formation in vivo. Pretreatment of the HA surface with methacryloyloxydecyl phosphate (MDP)-PEG prior to saliva incubation hydrophilized the surface and thereby reduced salivary protein adsorption and saliva-promoted bacterial attachment to HA. However, when MDP-PEG was added to the saliva-pretreated HA (S-HA) surface, its inhibitory effect on bacterial binding was completely diminished. S. mutans adhesion onto S-HA was successfully reduced by treatment of the surface with pyrophosphate (PP), which desorbs salivary components from S-HA. Treatment of S-HA surfaces with MDP-PEG plus PP completely inhibited salivapromoted S. mutans adhesion even when followed by additional saliva treatment. Finally, mouthwash with MDP-PEG plus PP prevented de novo biofilm development after thorough teeth cleaning in humans compared to either water or PP alone. We conclude that MDP-PEG plus PP has the potential for use as an antiadherence agent that prevents dental biofilm development.Dental plaque, a complex microbial biofilm, is the primary etiologic factor in dental caries. Colonization of enamel surfaces by the cariogenic bacterium Streptococcus mutans is thought to be initiated by attachment to a saliva-derived conditioning film, the acquired enamel pellicle (9). The acquired enamel pellicle is formed largely by adsorption of heterogeneous salivary proteins (1, 18) onto dental enamel (ϳ98% [wt/wt] hydroxyapatite [HA]) and promotes the adhesion of S. mutans by specific (2, 17) and nonspecific (4) mechanisms.Saliva contains a multitude of proteins that contribute to oral microbial ecology and biofilm formation (6,16,32). A variety of salivary proteins have been shown to modulate bacterial adhesion onto HA surfaces in vitro. Adsorption of specific salivary proteins, such as acidic proline-rich proteins (8) and agglutinin (3), promotes the adhesion of S. mutans onto HA surfaces by providing ligands for bacterial attachment. Many studies thus far have suggested that an initial bacterial adhesion promoted by salivary protein adsorption onto the enamel surface contributes to facilitate dental biofilm development.Recently, we reported the clinical relevance of saliva-promoted S. mutans adhesion in both de novo dental biofilm development and caries experience (29). Dental biofilm formation after thorough teeth cleaning was positively correlated with both salivary glycoprotein content and S. mutans a...

Poly(ethylene oxide)-based block copolymers with very high molecular weights for biomimetic calcium phosphate mineralization

“…caries) include the incorporation of antibacterial additives such as chlorhexidine 14,20 or silver 15,18 into dental care products and their regular application in dental hygiene. A further possibility to reduce adverse effects is to interrupt biolm formation 24 before caries bacteria can settle on the enamel.…”

“…In addition to inorganic compounds 9,10,13,21,37-39 polymers like xanthan, 40 pectin, 41 casein, 3 and others 24,[40][41][42] have also been used as additives in dental care products. Among others, these polymers are able to anchor on the surface of the teeth and act as barrier for protons or micro organisms.…”

The Development of Drug-Free Therapy for Prevention of Dental Caries

“…Our PPi-PEG copolymer demonstrated strong inhibition of S. mutans adhesion on both clean HA surfaces, as well as that covered by a saliva pellicle. However, it should be noted that, in previous studies, phosphorylated polymers were unable to replace an existing saliva pellicle (14, 31), suggesting that these polymers should be used during or immediately after dental hygiene procedures. The inhibitory mechanism of these polymers against S. mutans adhesion was likely through prevention of salivary protein adsorption as well as creation of a neutral, hydrophilic PEG layer on the HA surface.…”

“…The acquired enamel pellicle is formed through adsorption of salivary proteins onto the dental surface, which promotes the adhesion of S. mutans by specific (antigen I/II) and nonspecific mechanisms (14). Therefore, if the adsorption of salivary proteins and acquired enamel pellicle formation can be reduced and interrupted, the diseases caused by over-accumulation of dental biofilm may be better controlled.…”

Chimeric Peptides as Implant Functionalization Agents for Titanium Alloy Implants with Antimicrobial Properties

“…Several surface coating and functionalization strategies have been reported to overcome implant failure associated with infections. In an attempt to render the implant surface non-adhesive and/or to introduce antimicrobial surfaces, the use of polyethylene glycol (PEG) and its derivatives [14, 15], coatings of albumin [16], covalent attachment of conventional antibiotics [17-20], chlorhexidine [21], silver, nitrogen oxide [22, 23] and quaternary ammonia compounds [19, 24] have been used. While the activation of implant surfaces by these agents have been shown to reduce bacterial adhesion, existing covalent coupling strategies often require complex chemistry to execute, with the unwieldy requirement of specific functional groups on the surface with extensive optimization steps.…”