New phosphated poly(methyl methacrylate) polymers for the prevention of denture-induced microbial infection: an in vitro study

Abstract

Purpose: Poly(methyl methacrylate) (PMMA) has been widely used as a denture-base acrylic resin due to its excellent physical and mechanical properties. However, the material is highly prone to microbial fouling that often leads to Candida-associated denture stomatitis. Incorporation of phosphate groups into PMMA could facilitate adsorption of salivary antimicrobials and inhibit microbial adherence on the polymer surface. An in vitro study evaluated PMMA polymers containing varying amounts of phosphate group for their efficacy to inhibit Candida albicans adhesion, adsorb salivary histatin 5, and exhibit candidacidal activity. Methods: Six PMMA polymers containing 0%, 5%, 15%, 10%, 20%, and 25% of phosphate group were synthesized by bead (suspension) polymerization technique using mixtures of methyl methacrylate and methallyl phosphate as monomers. The efficacy of the polymers to inhibit the adherence of C. albicans was examined by using human saliva-coated polymer beads and radio-labeled C. albicans cells, as compared with that of PMMA. The potency of the phosphated PMMA polymers to adsorb histatin 5 was determined by measuring the radioactivity of the adsorbed labeled-peptide on the polymer surface. The candidacidal activity of the histatin 5-adsorbed polymers was assessed by using the fluorescence technique. The percent release of the fluorescent probe calcein from the C. albicans membrane caused by the disruption of the cell membrane was determined. The data were analyzed statistically by one-way ANOVA followed by Scheffé's test (α = 0.05 and n = 6). Results: The presence of $15% phosphate content in PMMA significantly reduced the salivamediated adhesion of C. albicans. Phosphated PMMA polymers showed significantly enhanced adsorption of histatin 5 in a phosphate density-dependent manner. The candidacidal activity of the histatin 5-bound polymers increased significantly with the increase in the phosphate content of the polymer. Conclusion: Phosphated PMMA polymers have the potential to serve as novel denture-base resins, which may reduce C. albicans colonization and prevent denture stomatitis.

Incorporation of Antimicrobial Macromolecules in Acrylic Denture Base Resins: A Research Composition and Update

“…PMMA with phosphate groups facilitates adsorption of salivary antimicrobials and inhibits microbial adherence on the polymer surface. The presence of 15% phosphate content in PMMA denture base significantly reduced the saliva‐mediated adhesion of C. albicans and enhanced adsorption of histatin 5 in a phosphate density‐dependent manner . A lower contact angle and a trend toward increased hydrophilicity were observed with an increased concentration of phosphate .…”

Monomer modifications of denture base acrylic resin: A systematic review and meta-analysis

“…From the included researches in the systematic review, the modification of MMA was done basically by certain monomers or solutions that can be categorized as fluoromonomers[2627282930] ( n = 5), phosphate monomers[313233] ( n = 3), methacrylic acid monomer[343536373839] ( n = 6), itaconate monomers[404142] ( n = 3), nitromonomers[543444546] ( n = 5), and nonspecific monomers or solutions ( n = 6). Nonspecific monomers include Norbonyl/phenyl methacrylate (NBMA/PHMA),[47] polyhedral oligosilsesquioxane (POSS),[48] methacrylated dendrimer (DD1),[49] 1,3-bis(3-methacryloxypropyl)-1,1,3,3 tetramethyl disiloxane (BMPMS),[50] silver nitrate (AgNO 3 ) solution,[51] and N -acetyl cysteine (NAC).…”

“…The monomers used to substitute with MMA (wt/vol%) were either experimentally synthesized[33424445474951] or purchased. [526272829303234353637383940414346485052] For the specimen preparation, the polymer beads were synthesized by bulk polymerization,[29474950] suspension polymerization,[2627283334] or from the commercially available pre-polymers.…”

“…The monomers used to substitute with MMA (wt/vol%) were either experimentally synthesized[33424445474951] or purchased. [526272829303234353637383940414346485052] For the specimen preparation, the polymer beads were synthesized by bulk polymerization,[29474950] suspension polymerization,[2627283334] or from the commercially available pre-polymers. The commercially available pre-polymers used were Lucitone 550,[30354345] Lucitone 199,[3132] Paladent 20,[48] Trevalon,[36] Vertex,[3744] DPI,[3839] Ondacryl,[5] Ivoclar Vivadent,[51] Biocryl,[404142] QC-20, Acron MC,[46] and Uniffasttrad.…”

Effects of trimethylsilane plasma coating on the hydrophobicity of denture base resin and adhesion of Candida albicans on resin surfaces

“…Studies have also reported that when a phosphate-containing monomer was synthesized and combined into PMMA, a significant decline in C. albicans colonization occurred because of the enhanced adsorption of histatin 5 (a type of antimicrobial peptide in saliva) in a phosphate density-dependent manner. 15,16 In addition, self-bonding polymer coatings 12 and hydrophilic coatings 17 have been used to reduce C. albicans adhesion to an antifungal denture.…”