Partial dentures are made from three main categories of materials: metal alloys, acrylic resin, and flexible thermoplastics. Most partial dentures combine more than one of these, using one material for the structural framework and others for the gum-colored base and the replacement teeth. The specific combination affects how the denture feels, how long it lasts, and how it looks in your mouth.
Metal Alloy Frameworks
The most traditional and durable option is a cast metal framework. These are almost always made from a cobalt-chromium alloy, where cobalt is the primary ingredient and chromium and molybdenum are the main supporting elements. Small amounts of silicon, manganese, iron, and carbon round out the mix. Industry standards require that cobalt, chromium, and nickel together make up at least 85% of the alloy by weight, with chromium alone accounting for at least 25%.
Cobalt-chromium frameworks are thin, rigid, and strong. That rigidity is actually a benefit: it distributes chewing forces evenly across your remaining teeth and gums rather than concentrating pressure in one spot. The trade-off is that the metal clasps (the small hooks that grip your natural teeth) are visible when you smile, and some people find the metallic feel unpleasant at first. Metal partial dentures have the longest track record for durability, with one study finding a mean survival of 8 years and survival rates ranging from 48% to 100% across follow-up periods of 1 to 20 years.
Titanium is a newer alternative to cobalt-chromium. It is lighter, highly biocompatible, and a good choice for people with nickel or cobalt sensitivities. A forged titanium framework offers improved strength and hardness compared to standard titanium, and it is easier for dental technicians to grind and polish, which can mean a more comfortable final fit.
Acrylic Resin Bases
The pink, gum-colored portion of most partial dentures is made from acrylic resin, specifically polymethyl methacrylate (PMMA). This material starts as a powder and liquid that are mixed together. The liquid contains single molecules called monomers, and when heated or chemically activated, those monomers link together into long chains to form a hard plastic. PMMA became the standard decades ago because it is lightweight, easy to color-match to your gums, inexpensive, and simple for labs to work with.
The main weakness of acrylic is that it can crack or break if dropped or subjected to repeated stress. Some residual monomer molecules may remain in the finished product, and in rare cases these can irritate sensitive tissue or trigger an allergic response. All-acrylic partial dentures (sometimes called “flippers”) use acrylic for both the base and the clasps. They cost less than metal-framework designs but are bulkier, less stable, and generally considered a temporary solution.
Flexible Thermoplastic Materials
Flexible partial dentures are made from thermoplastic resins, most commonly a type of nylon called polyamide. Valplast is the best-known brand. Unlike acrylic, these materials contain no residual monomers, making them a practical option if you have a sensitivity to traditional acrylic. The nylon is heated until it becomes pliable, then injected into a mold, so there is no chemical mixing involved.
The flexibility serves a functional purpose. The base can flex slightly as it seats over your gums, creating a snug seal along the borders that improves retention without relying on visible metal clasps. Instead, the clasps are made from the same tooth-colored or gum-colored nylon, so they blend in. This makes flexible partials popular for front-of-mouth replacements where appearance matters most. The downside is that the same flexibility that makes them comfortable also means they do not distribute biting forces as evenly as a rigid metal framework. They can also be harder to reline or repair if the fit changes over time.
High-Performance Polymers: PEEK
A newer class of material called PEEK (polyetheretherketone) sits between metal and nylon in terms of stiffness. It is a high-performance thermoplastic that can be milled by computer from a solid block or fabricated using a lost-wax technique similar to metal casting. PEEK is metal-free, lightweight, and has an elastic modulus (a measure of stiffness) much closer to bone than cobalt-chromium, which provides a cushioning effect on chewing forces.
PEEK clasps grip teeth with less force than cobalt-chromium clasps, which sounds like a disadvantage but is actually useful for patients with weakened or periodontally compromised teeth that cannot handle strong clamping pressure. To compensate for the lower grip, PEEK clasps are designed slightly thicker and placed in deeper undercuts on the tooth. Short-term clinical evidence shows satisfactory performance with few technical complications, though long-term data is still limited compared to metal frameworks. PEEK is also fully biocompatible and a strong choice for anyone with metal allergies.
What the Replacement Teeth Are Made Of
The artificial teeth attached to a partial denture are a separate material from the framework and base. They come in three main types: acrylic resin, composite resin (a blend with fine filler particles for extra hardness), and ceramic (porcelain).
Acrylic teeth are the most common. They bond easily to an acrylic base, are simple to adjust in the dental chair, and produce less of a “clacking” sound when your teeth come together. Porcelain teeth are harder and more resistant to wear, which helps them maintain their shape over many years. However, porcelain can wear down the natural teeth it bites against, and it produces an audible click on contact that some people find annoying. Porcelain teeth also cannot chemically bond to an acrylic base, so they are mechanically locked in place.
Matching the right tooth material to your situation matters. If your partial opposes natural teeth, your dentist will consider how the materials interact. Acrylic against porcelain, for instance, can wear the acrylic down faster, creating an uneven bite over time. The choice often comes down to balancing durability with compatibility.
Options for Allergies and Sensitivities
If you react to standard acrylic or metal, several hypoallergenic alternatives exist. Thermoplastic resins as a group, including nylon, acetal, polycarbonate, and PEEK, are monomer-free and considered non-allergenic with high biocompatibility. Acetal resin is particularly useful for making lightweight, tooth-colored clasps and even full frameworks for patients who cannot tolerate metal. Urethane-based resins are another option, as they lack the chemical groups responsible for acrylic allergies. Your dentist can often identify the specific allergen through patch testing and then select a material that avoids it entirely.