Orthodontic elastics, commonly known as rubber bands, are small, stretchy medical-grade bands. They apply continuous force to guide teeth and jaws into their correct positions, working with braces or aligners to address bite discrepancies. An orthodontist uses various sizes and strengths of these bands for each individual’s treatment needs.
How Orthodontic Elastics Work
Orthodontic elastics function by creating consistent, gentle pressure that encourages the gradual movement of teeth and the remodeling of jaw bone. When an elastic is stretched between different points on the braces, it generates tension that pulls the teeth in a predetermined direction. This sustained force signals the body to initiate a biological process where bone is removed on one side of the tooth and new bone is laid down on the other, allowing the tooth to shift. The orthodontist strategically determines the precise placement and strength of these elastics to achieve specific directional forces for optimal results.
Specific Functions of Different Elastic Classes
Orthodontic elastics are categorized and applied based on the specific type of bite correction required. Each class targets a distinct malocclusion, applying force to facilitate particular tooth and jaw movements.
Class II Elastics
Class II elastics are primarily used to correct a Class II malocclusion, commonly known as an overbite, where the upper front teeth protrude significantly over the lower front teeth. These elastics typically attach from a hook on an upper canine bracket to a hook on a lower molar bracket. By applying a consistent pulling force, Class II elastics help move the upper teeth backward and the lower teeth forward, aiming to achieve a more harmonious bite relationship.
Class III Elastics
Class III elastics address a Class III malocclusion, characterized by an underbite where the lower teeth sit in front of the upper teeth. The placement for these elastics usually involves attaching them from a hook on a lower front tooth (such as a canine) to a hook on an upper back tooth (like a molar). This configuration applies force to move the lower teeth backward and the upper teeth forward, thereby reducing the underbite and promoting a more aligned bite.
Crossbite Elastics
Crossbite elastics are employed to correct crossbites, a condition where one or more upper teeth bite inside their opposing lower teeth. These elastics are often attached diagonally, stretching from an upper bracket to a lower bracket on the opposite side of the mouth. For example, they might run from the inside of an upper tooth to the outside of a bottom tooth. This specific force helps move the misaligned teeth laterally into their correct positions, ensuring the upper teeth properly sit outside the lower teeth.
Vertical Elastics
Vertical elastics, sometimes referred to as triangle or box elastics, are used to address issues related to the vertical alignment of teeth. Vertical elastics specifically target open bites, where there is a gap between the upper and lower teeth when the mouth is closed. They are placed to apply force that helps extrude certain teeth, guiding them into proper contact. Triangle elastics, a type of vertical elastic, are often hooked in a triangular pattern, for instance, from an upper canine to a lower canine and lower first premolar, to help close an open bite. Box elastics, another vertical application, attach to four teeth in a rectangular configuration, two on the upper and two on the bottom, to help close the bite and ensure teeth meet properly.
Midline Elastics
Midline elastics are used to correct discrepancies in the alignment of the upper and lower dental midlines. The dental midline refers to the imaginary line between the two upper central incisors and the two lower central incisors. When these lines do not align, midline elastics are applied to gently shift teeth to bring the centers of the upper and lower arches into harmony. The elastic may be attached from a hook on an upper canine to a hook on the lower canine, sometimes crossing the midline diagonally to achieve the desired correction.
Wearing and Caring for Your Orthodontic Elastics
Consistent wear of orthodontic elastics is important for successful treatment outcomes. Orthodontists typically recommend wearing elastics for 20-22 hours per day, including while sleeping. Removing them only for eating and brushing teeth is generally advised, though some orthodontists may suggest wearing them while eating to enhance movement. Non-compliance can significantly prolong treatment time and hinder progress.
Elastics lose their elasticity and effectiveness over time, making frequent changes necessary. It is generally recommended to change elastics at least 2-3 times a day, or every 12 hours, to maintain consistent force, often after each meal and before bedtime. Before handling elastics, it is important to wash hands thoroughly to prevent introducing bacteria into the mouth.
Orthodontic elastics are designed for single use and should be discarded after removal; do not rinse or wash them. Patients should always have extra elastics readily available in case one breaks or is lost. Initial soreness is common when starting elastic wear, but this discomfort typically subsides within a few days of consistent use. If discomfort persists or elastics break frequently, contacting the orthodontist is important for guidance.