All braces use pressure to move the teeth. This pressure is transferred to the roots and leads to a degradation of the bone both on the ‘push’ side and on the ‘pull’ side of the roots of the teeth. During the course of orthodontic treatment this can often lead to paresthesia in the teeth and occasionally, to pain.
In the case of removable braces, after being installed by the orthodontist or after they are tightened with the integral screw, slight paresthesia can result in the teeth for a couple of days. With fixed braces, particularly the bracket-brace (multi-bracket appliance), most patients normally experience very sensitive teeth for a few days after the appliance has been installed or the wires have been changed. In some very sensitive patients, this can even result in toothache. These patients can generally take normal painkillers to get them through this short period of pain.
Tip: Any movement of the teeth can cause paresthesia, and more so in older patients. You have to be a bit tough to put up with orthodontic treatment!