A cracked tray, damaged connector, or unreliable adjustment mechanism can change how a sleep appliance holds the jaw and loads the teeth. Some problems are repairable; others make replacement more appropriate. The decision depends on the appliance design, the extent of damage, the condition of the mouth, and whether suitable parts or laboratory support are available.
Contact the provider when damage is noticed and describe what has broken. Do not continue wearing a device with loose pieces or an uncertain fit without professional advice, and do not glue, heat, or bend it at home. If the appliance is part of sleep apnea treatment, a repair delay also raises a medical treatment question. The dental provider and sleep-care clinician should help coordinate an appropriate interim plan rather than leaving you to substitute an unrelated guard or abandon prescribed care.