Braces are made from a combination of materials that work together: metal or ceramic brackets bonded to your teeth, archwires threaded through them, and small ties holding everything in place. Each component uses different alloys, ceramics, or polymers chosen for strength, flexibility, and safety inside your mouth. Here’s what goes into each piece.
Brackets: The Pieces Bonded to Your Teeth
The small squares glued to the front of each tooth are called brackets, and they come in several material options depending on your priorities around visibility, durability, and cost.
Stainless steel is the most common bracket material. Orthodontic brackets typically use type 304, 316, or 17-4 PH stainless steel, all chosen for their strength and corrosion resistance in a wet environment like your mouth. These are the classic silver-colored brackets most people picture when they think of braces.
Ceramic brackets are made from aluminum oxide, the same compound that forms sapphire and ruby in nature. They come in two types. Polycrystalline brackets are made by fusing many tiny aluminum oxide crystals together at high temperatures, producing a tooth-colored but slightly opaque result. Monocrystalline brackets are grown from a single crystal, making them more translucent and closer to invisible on your teeth. The single-crystal version is also stronger and more resistant to fracture than the fused type, though both are more brittle than metal.
Sapphire brackets are essentially the monocrystalline version taken a step further. Lab-grown sapphire crystals are cut and shaped into bracket form, and sapphire ranks 9 out of 10 on the Mohs hardness scale. Its wear resistance is about 1.5 times that of steel. The tradeoff is that ceramic and sapphire materials have lower toughness than metal, meaning they can crack or chip under sudden force even though they resist scratching well.
Archwires: The Force Behind Tooth Movement
The thin wire running across your teeth through each bracket is the archwire, and it’s the component that actually generates the force moving your teeth. Orthodontists swap between different wire materials as treatment progresses, starting with gentler wires and working up to stiffer ones.
Nickel-titanium (NiTi) wires are usually the first ones placed. They contain roughly 55 to 58% nickel and 42 to 45% titanium by weight, and they were first used in orthodontics in 1972. What makes them special is their “shape memory”: you can bend them significantly, and they slowly return to their original shape, applying a gentle, continuous force to crooked teeth. They also have a high elastic limit, meaning they flex a long way before permanently deforming. This makes them ideal for the early stages of treatment when teeth are most out of alignment.
Copper-nickel-titanium (CuNiTi) wires add about 6.9% copper to the mix (with roughly 50.7% nickel and 42.4% titanium). The copper changes the temperature at which the wire activates its shape memory, allowing orthodontists to fine-tune how much force the wire delivers at mouth temperature.
Stainless steel wires are stiffer and used in later stages when teeth need more precise positioning. They don’t have shape memory but provide strong, predictable force for final adjustments.
Beta-titanium (TMA) wires fall between NiTi and stainless steel in stiffness. They’re also nickel-free, which matters for patients with metal sensitivities.
The Glue Holding Brackets On
Brackets are attached to your teeth with a composite resin adhesive, not a simple glue. These adhesives contain a resin base mixed with filler particles, primarily quartz. The quartz filler gives the adhesive high compressive strength and stiffness while matching the way tooth enamel expands and contracts with temperature changes. That thermal match is important: if the adhesive shrank or swelled differently than your tooth, brackets would pop off every time you drank something hot or cold. A special light is used to cure (harden) the resin after the bracket is positioned.
Ligatures, Bands, and Elastic Ties
The small colored rings you choose at each appointment are called ligatures or elastic ties, and they hold the archwire into the bracket slot. Traditional versions are made from natural latex rubber, specifically cis-1,4 polyisoprene chains treated with preservatives like ammonia. Latex gives excellent elasticity, flexibility, and resilience.
For patients with latex allergies, synthetic alternatives use polyurethane, silicone, or styrene-butadiene rubber to replicate those elastic properties without the allergenic proteins found in natural latex. The larger rubber bands sometimes worn between upper and lower jaws (called interarch elastics) follow the same latex or synthetic split.
Some bracket systems skip elastic ties entirely. Self-ligating brackets have a built-in clip or gate that holds the wire in place, eliminating one material from the equation and reducing friction between wire and bracket.
Options for Nickel Allergies
Nickel sensitivity is a real consideration with braces. It’s estimated to affect about 30% of girls and 3% of boys, with rates especially high (around 31%) in adolescents who have pierced ears. Since standard stainless steel brackets and NiTi wires both contain nickel, patients with known allergies have several alternatives.
Nickel-free bracket options include ceramic brackets, polycarbonate (plastic) brackets, pure titanium brackets, and gold brackets. For archwires, titanium molybdenum alloy (TMA), pure titanium, fiber-reinforced composite, and gold-plated wires all avoid nickel. Clear aligners sidestep the issue entirely since they’re made from plastic. If you know you react to nickel (from jewelry, belt buckles, or previous dental work), bring it up before treatment starts so your orthodontist can plan around it.
How These Materials Work Together
A full set of braces isn’t one material but a system. The archwire provides the force, the brackets transfer that force to individual teeth, the adhesive keeps the brackets anchored, and the ligatures keep the wire seated in each bracket. At different stages of treatment, your orthodontist may change the archwire material to shift from gentle alignment forces to firmer repositioning forces, even while the brackets stay the same throughout.
The material choices also affect day-to-day life. Ceramic and sapphire brackets stain less than the elastic ties around them, so discoloration you notice is usually the ligatures, not the brackets themselves. Metal brackets are virtually indestructible under normal eating, while ceramic brackets can fracture if you bite into something hard at the wrong angle. Wire material determines how often you need adjustments: NiTi wires deliver steady force over longer periods, while stainless steel wires may need more frequent tightening.