Straightening teeth relies entirely on the successful bond between the tooth enamel and the orthodontic bracket, achieved using a specialized dental adhesive, often called “braces glue.” This adhesive must be strong enough to withstand the continuous forces of chewing and the pull of the archwire, yet permit safe, non-destructive removal at the end of treatment. The longevity of this bond is a primary concern, as failure can interrupt the planned course of treatment.
The Intended Lifespan of Orthodontic Adhesives
The adhesive used to secure brackets is engineered for stability throughout the entire duration of the orthodontic process. This period typically ranges from 18 months to three years. The most common bonding agents are resin-based composites, which create a mechanical lock with the etched surface of the tooth enamel. This bond is achieved by preparing the tooth surface and then curing the composite with a specialized light.
These composite materials resist the harsh, wet, and acidic environment of the mouth while maintaining the strength needed to transmit orthodontic forces. Although the adhesive is intended to last the full treatment time, most bonding failures occur within the first six months after the braces are placed. The overall failure rate remains low, generally falling within a 4% to 8% range across all bonded brackets.
Factors Influencing Adhesion Failure
The durability of the adhesive bond is challenged by patient habits and the forces exerted within the mouth. Dietary choices are a frequent source of premature failure, particularly consuming hard, sticky, or crunchy items. Foods like nuts, popcorn kernels, hard candies, and ice can generate forces that exceed the bond strength, causing the bracket to shear off the tooth surface. Sticky foods, such as caramels or taffy, can pull on the brackets, gradually weakening the adhesive layer.
Mechanical trauma, often unconscious, also contributes significantly to bond breakdown. Habits such as biting on pens, pencils, or fingernails introduce localized, high-impact forces the adhesive is not designed to tolerate. Participation in sports without a mouthguard can result in a sudden impact that dislodges multiple brackets.
Poor oral hygiene can indirectly compromise the bond’s integrity. Plaque buildup near the bracket and tooth junction creates an acidic environment that leads to demineralization of the surrounding enamel. This weakening of the enamel substrate can cause the bond to fail, even if the adhesive remains intact.
Failure can sometimes be attributed to technical issues during initial placement, though this is less common. If moisture contaminates the tooth surface during bonding, the adhesive may not properly cure or form a strong micromechanical connection. Similarly, if the operator does not fully integrate the cement into the mesh base of the bracket, the initial bond strength may be compromised. Excessive overbite or other bite irregularities that cause direct contact between opposing teeth and the brackets can also place repeated, destructive forces on the bond.
What to Do When a Bracket Comes Loose
If a bracket feels loose or detaches from the tooth surface, remain calm and assess the situation. If the bracket has come completely off, carefully remove it from the mouth, save it, and bring it to the orthodontist’s office. If the bracket is still attached to the archwire but is sliding or rotating, leave it in place.
If the loose bracket is causing irritation or rubbing against the cheek or gum tissue, press a small piece of orthodontic wax over the appliance to smooth the surface temporarily. Contact the orthodontic office as soon as possible to schedule a repair appointment.
A loose bracket stops the movement of the tooth, which can slow down or halt treatment progress. The orthodontist must remove any remaining adhesive and re-bond a new bracket. This re-bonding process ensures the tooth continues to move correctly and keeps the treatment plan on schedule. Delaying the repair allows the tooth to shift back toward its original position, leading to unwanted setbacks in the alignment process.