Denture Materials Basics

Denture Materials

• Denture cleansers are categorized into abrasives and solutions.
• Abrasive cleansers are paste-based formulations used with soft-bristled brushes.
• Solution cleansers include hypochlorites, oxygenating agents, and mild acids.
• Sodium hypochlorite is an antibacterial agent that removes adherent proteins and kills organisms.
• Hypochlorites can be corrosive to metal frameworks and may cause discoloration.
• Oxygenating agents, like peroxides, perborates, and percarbonates, are dissolved in tablets or powders.
• Oxygenating agents should not be used with soft liners as they harden the liner.
• Denture adhesives are typically unnecessary if proper fabrication processes are followed.
• Denture adhesives are used in emergencies for immediate stabilization.
• Denture adhesives are helpful for patients with limited residual ridges, cleft palates, or post-cancer treatment prostheses.
• Some denture cleaners can cause mild acid buildup in saliva, potentially etching enamel and dentin in patients with natural teeth.
• Powder-based denture cleansers are sprinkled on a wet denture base and inserted into the mouth.
• Paste-based denture cleansers are water-resistant and spread to form a thin layer.

Denture Base Materials

• Denture bases are made from polymers or metal, with polymers being the most popular.
• Polymers are easily shaped, lightweight, and used for covering the residual ridge, providing facial contour, holding denture teeth, and ensuring intimate mucosal contact.
• Loss of facial support can lead to a sunken appearance.
• Polymethyl methacrylate (PMMA) is a common material for denture base construction.
• Denture base resin polymerization methods include heat, chemical reaction (autopolymerized), microwave, and light activation.

Resin-Based Dentures

• Heat-polymerized materials are a popular choice for denture bases.
• Acrylic polymerization stages include initiation, propagation, and termination.
• The dough stage is ideal for working with acrylic.
• Dentures must be kept wet to prevent water absorption and expansion.
• Resin shrinkage during polymerization is approximately 0.3 to 0.5%.
• Auto-polymerized materials are also commonly used for dentures.
• Microwave-cured acrylic resin allows for rapid curing.
• Light-cured resin offers precise and controlled polymerization.

Metal-Based Dentures

• Metal-based dentures feature a metal base against the oral mucosa and a polymer layer for gingiva and tooth retention.
• Metal-based dentures offer a more accurate fit, transfer heat from foods and fluids, and a single cartridge delivery system.

Laboratory Reline Materials

• Lab-processed relines involve roughening the denture surface and placing impression material directly on the base.
• One type of lab-processed reline adds new denture material and polymerizes it under heat and pressure. This results in a stronger reline, resistant to fluid absorption and color change.
• Another type of reline involves soft silicone-based materials, providing flexibility without the risks associated with heat-processed relines.
• Silicone-based relines can be porous and prone to bacteria and fungi accumulation.

Denture Tissue Conditioners

• Denture tissue conditioners provide a cushioning and temporary liner to absorb loads.
• Tissue conditioners are used for irritated and inflamed tissues.
• Tissue conditioners must be replaced frequently to prevent hardening and loss of resiliency.
• The loss of resiliency is due to plasticizer leaching.

Denture Repair

• Denture repair involves using autopolymerizing resins to replace missing teeth or re-join fractured parts.
• Undercuts and locks can improve the strength of repairs.
• Heat-polymerized repairs provide greater strength than chemically polymerized repairs.

Impression Materials

• Alginate hydrocolloid is an irreversible hydrocolloid used for impressions.
• Alginate setting can be accelerated by adding cold water or increasing the alginate concentration.
• Breaking the seal around the impression and using a snapping motion can also speed up setting.

This quiz covers essential information about denture materials, focusing on cleansers and adhesives used in dental practices. It explores the types of cleansers, their formulations, and the importance of proper fabrication for denture stability. Additionally, it discusses the specific features and cautions concerning various denture cleaning agents.