During orthodontic treatment with clear aligners, patients receive small, soft cylindrical devices called aligner chewies or seaters. These accessories bridge the minute gap that can exist between the plastic tray and the teeth. Their purpose is to maximize contact, ensuring the aligners are fully seated over the teeth and any bonding attachments. Full seating is necessary for the programmed application of gentle forces required for successful tooth movement.
The Primary Function and Varieties
The function of a chewie is eliminating the “air gap” that forms when a new aligner is placed. If the aligner is not flush against the teeth, the prescribed forces cannot be delivered accurately. This lack of proper engagement can lead to tracking issues, where the teeth fail to move into the position dictated by the treatment plan. Uneven seating can also cause localized pressure points, leading to discomfort or irritation.
These seaters are constructed from flexible, medical-grade materials such as silicone or a soft thermoplastic elastomer foam. While usually cylindrical, they can also be found in Y-shaped or U-shaped configurations. These orthodontic tools are distinct from sensory chew toys used for therapeutic or behavioral support. The material’s physical properties allow for repeated, high-force compression without tearing or losing resilience.
Step-by-Step Guide for Effective Seating
Begin by placing the aligner tray fully into the mouth, pressing it down with your fingers as much as possible. Next, visually inspect the aligner, particularly around the edges and over the attachments, looking for any visible space between the plastic and the tooth surface. These air gaps indicate incomplete mechanical seating that requires targeted attention. A fully seated aligner should appear almost invisible and feel completely secure.
Once a gap is identified, place the chewie horizontally between the upper and lower arches directly over the area that is not fully seated. Using a controlled, gentle biting motion, apply pressure to the chewie, holding the bite for five to ten seconds. This sustained compression physically molds the aligner plastic around the tooth and any bonding attachments. The action focuses on specific pressure points.
After seating a specific spot, move the chewie systematically across the entire arch to ensure uniform fit. Start at the front incisors and work back to the molars on one side, then repeat the process on the opposite side. Finishing the routine with a final bite on the chewie using the front teeth confirms secure seating across the entire tray.
Usage Schedule and Maintenance
The recommended schedule involves using the chewie immediately after inserting the aligners back into the mouth. This is especially important when switching to a new tray, as the initial fit is the tightest and requires the most effort. The seating routine should last between five and ten minutes total, ensuring the aligner is fully engaged before continuing with the day.
Maintaining the hygiene of the aligner seater is necessary to prevent bacterial buildup. The device should be washed regularly using mild hand soap and cool water, then allowed to air dry completely. These devices are subject to significant cyclical loading, and their elasticity will naturally diminish over time with repeated use. Once a chewie begins to fray, tear, or loses resistance, it must be replaced to ensure the seating force remains effective and consistent throughout the treatment.