Orthodontic elastics, commonly called rubber bands for braces, are essential components of orthodontic treatment. Their primary function is to apply a specific, continuous force to guide the upper and lower teeth into proper alignment, correcting bite problems like overbites, underbites, and crossbites. These bands complement the work of the brackets and wires, ensuring the jaws and individual teeth meet correctly. The question of reusing these bands is directly connected to their mechanical function and the biology of tooth movement.
The Function and Degradation of Orthodontic Elastics
Orthodontic elastics are engineered to deliver a precise, measurable amount of light force to stimulate biological tooth movement. This process relies entirely on the consistency of the pressure applied. The bands, typically made from latex or non-latex polymers, begin to degrade almost immediately after being placed in the mouth and stretched.
The oral environment is highly challenging for these materials due to constant stretching from chewing and speaking, as well as exposure to saliva, fluctuating temperatures, and varying pH levels. Studies show that a significant portion of the force these elastics deliver is lost within the first few hours of wear.
This rapid force decay is a result of mechanical fatigue and environmental factors breaking down the polymer structure. Once the material loses this tension, it no longer provides the gentle, consistent force necessary to move teeth effectively. A worn-out band essentially becomes a passive piece of material that fails to achieve its therapeutic purpose.
The Risks Associated with Reusing Bands
Reusing orthodontic elastics is strongly discouraged because it compromises the effectiveness of the treatment and introduces significant hygiene concerns. The most important reason is the immediate and substantial drop in force delivery after the initial use. A band that has already stretched and degraded will not exert the required calibrated pressure, rendering the intended tooth movement ineffective.
When the prescribed force is inconsistent or too low, the clinical risk is that treatment progress slows down considerably, leading to extended overall treatment time. Instead of moving smoothly, teeth may move erratically or not at all, causing delays that add months to the total duration of the braces treatment. The goal of continuous, gentle pressure is lost when old, weakened bands are reapplied.
Beyond mechanical failure, reusing elastics presents a clear oral hygiene risk. Used bands have been exposed to saliva, food particles, and the natural bacteria present in the mouth. Reintroducing a band that has accumulated these contaminants can increase the risk of oral health issues, such as gum irritation or the accumulation of plaque-causing bacteria around the braces.
Proper Elastic Replacement Protocol
To ensure treatment stays on track, patients must adhere to a consistent elastic replacement schedule. Orthodontists advise replacing the elastics multiple times a day to maintain a steady, therapeutic force. The standard recommendation is to use a fresh pair of elastics at least three to five times per day, or after every instance they are removed.
Elastics should be removed only for necessary activities like eating and brushing, and a new, unused band must be applied immediately afterward. This routine ensures that the teeth are constantly under the intended pressure. Always use the exact size and strength of elastic provided by the orthodontist, as using the wrong one can apply too much or too little force.
Keeping a supply of elastics readily available is a good strategy, with extras stored in a wallet, backpack, or car. If a patient runs low, they should contact their orthodontist immediately for a replacement pack. Substituting orthodontic elastics with regular rubber bands is dangerous, as they are not manufactured for intraoral use and can apply excessive, damaging force.