2-Methacryloyloxyethyl Phosphorylcholine Polymer Treatment of Complete Dentures to Inhibit Denture Plaque Deposition

Summary

Removable poly(methyl methacrylate) (PMMA) dentures are prone to bacterial adherence and plaque formation. Denture plaque-associated infection is a source of serious dental and medical complications in the elderly. This paper introduces a novel protocol to treat PMMA dentures with 2-methacryloyloxyethyl phosphorylcholine polymer, poly(MPC-co-BMA-co-MPAz), to suppress plaque deposition on PMMA dentures.

Abstract

Removable dentures made of poly (methyl methacrylate) (PMMA) are prone to bacterial adherence and dental plaque formation, which is called denture plaque. Denture plaque-associated infection is a source of serious dental and medical complications in the elderly. 2-Methacryloyloxyethyl phosphorylcholine (MPC) is a well-known biomedical material that exhibits marked antithrombogenicity and tissue compatibility because of its high resistance to protein adsorption and cell adhesion. Therefore, MPC polymer coatings are suggested to have the potential to inhibit plaque deposition on the surface of PMMA dentures. However, coating MPC polymer on the surface of a PMMA denture is a complex procedure that requires specialized equipment, which is regarded as a major barrier to its clinical application.

Here, we introduce a new MPC polymer treatment procedure that uses poly (MPC-co-BMA-co-MPAz) (PMBPAz) to prevent denture plaque deposition on removable dentures. This procedure enables the MPC coating of PMMA denture surfaces in a simple and stable manner that is resistant to various chemical and mechanical stresses due to the MPC layer of PMBPAz that is covalently bound to the PMMA surface by ultraviolet light irradiation. In addition, the procedure does not require any specialized equipment and can be completed by clinicians within 2 min. We applied this procedure in a clinical setting and demonstrated its clinical utility and efficacy in inhibiting plaque deposition on removable dentures.

Introduction

Oral healthcare plays an important role in the prevention of opportunistic infections and aspiration pneumonia in the physically vulnerable elderly. Oral healthcare, consisting of brushing after each meal, cleaning dentures, and receiving professional oral health care, plays a vital role in reducing the incidence of such diseases^1-3. In particular, poor oral hygiene is strongly associated with aspiration pneumonia in the physically vulnerable elderly. Therefore, more attention should be paid to the oral health care of elderly patients, who have limited ability to clean their dentures by themselves⁴.

Even in developed c....

Protocol

1. Preparation of PMBPAz Solution (Figure 1)

1. Synthesize MPC following a previously reported industrial procedure¹⁵.
2. Synthesize the photoreactive MPC polymer PMBPAz using conventional radical polymerization of MPC, BMA, and MPAz in ethanol, as previously described¹⁴.
   NOTE: PMBPAz should contain 60%, 30%, and 10% (mol %) of the aforementioned monomer units, respectively. Refrigerate the PMBPAz dissolved in ethanol to prepare a 0.5 wt% solution before use.
3. Before treating the PMMA surface, allow the PMBPAz ethanol solution to stand for 30 min at room temperature.

Results

PMBPAz treatment enables the MPC coating of PMMA surfaces through a simple and short method and maintains the plaque inhibition effect of the MPC polymer. This procedure does not require any specialized equipment and can be performed chair-side by clinicians within 2 min. Following protocol step 2, the PMBPAz treatment of removable complete dentures from 11 edentulous patients was successfully conducted in a clinical setting without any substantial problems. The mean percentage plaque ind.......

Discussion

Mechanism of the PMBPAz Coating

It is challenging to bind MPC polymers to a PMMA surface in a simple and stable manner. Here, we used a new photoreactive monomer bearing a phenylazide group, MPAz, which polymerizes with other monomers through a conventional free-radical polymerization procedure, resulting in a polymer with phenylazide side chains. The phenylazide groups are decomposed by UV irradiation to form nitrene groups, which are highly reactive radical groups that can covalently bind to al.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Ultrasonic Cleaner	Aiwa Medical Engineering	AU-12C	Clean in distilled water before stain the denture
UVP UV Crosslinker DL-1000	Funakoshi	95-0174-03	UV light irradiation for 2 min before use
Lightbox S	Suntec	6542	capturing in this box after stain the denture
Adobe Photoshop CS6 Extended	Adobe		Calucurate and quantify