Implanted devices and dental equipment

Most dental equipment does not interfere with a modern cardiac device in a patient in the chair, but the reassurance rests on small in-vivo studies of patients who were not pacemaker-dependent, while the bench studies that frightened everyone were real findings under conditions a clinic rarely reproduces. A 2020 systematic review of eighteen studies found that most of the twelve in-vitro studies recorded interference close to the lead or at high sensitivity settings, and none of the six in-vivo studies recorded interference that altered device function at clinical distances and settings. Two exceptions stand out: magnetostrictive ultrasonic scalers interfered with pacing at chair-side distances in older bench work, and monopolar electrosurgery is the dental instrument that, in one bench study, made a defibrillator deliver therapy for a fibrillation that was not there. The working approach described here is to know which device is present and what its manufacturer says, to isolate an unshielded device and use piezoelectric or hand instrumentation instead of a magnetostrictive scaler, to use bipolar rather than monopolar electrosurgery, to follow the hospital's protocol in hospital, and to keep a magnet available for patients with vagus nerve stimulators. The common thread is deferring to the authority closest to the device — the manufacturer's labelling, the treating neurologist, the institution's protocol — rather than one universal rule, and the evidence for the non-cardiac devices is thinner still, often a single bench test or case report.