Cardiac Implanted Devices and Electronic Dental Instruments

Electronic dental instruments, like ultrasonic scalers or apex locators, could potentially interfere with some implantable cardiac devices, such as pacemakers or implantable cardioverter-defibrillators.

Cardiovascular implantable electronic devices (CIEDs) (see below) use electrical impulses to maintain proper heart rhythm. They are becoming more common as the initial population into which they were introduced ages with an increased life expectancy, and as implantations have increased.^1-6 This means patients, dental professionals and staff are more likely to have CIEDs, increasing the possibility of electromagnetic interference from electronic dental equipment.

There is a known history of common electronic devices, even cellphones and tablets,⁷ interfering with CIEDs. In dentistry, there have been conflicting reports regarding whether ultrasonic devices such as scalers and curing lights might interfere with automatic electronic functions of CIEDs. Electromagnetic interference may cause an interruption in or a change of pacing, or send a positive signal that a shock is needed. A number of in-vitro tests in the 1990s and early 2000s found that ultrasonic electronic dental devices caused interference in pacing and other functions, but many argue that in-vitro laboratory tests do not exactly mimic the human body and dental procedure conditions, and newer models of CIEDs should be more adequately shielded from electronic interference.^{2, 4, 5} As more people enter dental operatories with CIEDs, it is important to be aware of the risk of potential interactions with ultrasonic dental devices.^{1-6, 8}

CIEDs include pacemakers, which regulate cardiac pacing through an electric current, and implantable cardioverter-defibrillators, which analyze cardiac rhythm and deliver an impulse when an anomaly is detected.^{2, 3, 7-12}  CIEDs consist generally of two main components: a sealed capsule containing the power source, usually implanted inferior to the left clavicle (the subclavian pocket), subcutaneously or subpectorally, with a wire lead that follows the subclavian vein into the heart.^{2, 3, 7, 9-12}  Pacemakers have been in use since the 1960s,⁹ and early versions could only provide a static pulse; more modern versions can provide ‘on demand’ pacing, which can inhibit or trigger cardiac pulse as needed.^{3, 12}

Early pacemaker models also were not well protected or shielded from electromagnetic interference, but more modern CIEDs have been designed with potential electromagnetic interference in mind,^{2, 5, 13} using “hermetically sealed casing”² and “filters, rejection circuits, and bipolar modes”² to limit the risks of such interference.  The fact that older models lacked these protective measures may have led to many early reports of the high risks of interference with these devices.^{3-5, 10, 13, 14}

All types of tested electronic dental devices have shown some potential for causing electromagnetic interference in CIEDs (Table 1).  However, there is conflicting evidence, and most of the positive results come from in-vitro studies.  It is thought that human tissue provides shielding and other protection from electromagnetic interference that cannot be replicated in a laboratory setting.^{2, 6, 11}  Many instruction manuals for electronic dental devices discourage use of these devices with patients who have CIEDs,^{1, 14, 15} but many researchers believe that newer CIEDs are designed to lower the risk of interference from electromagnetic sources.⁶ While some researchers claim that clinical interference from ultrasonic dental devices is “highly improbable,”¹⁵ the theoretical possibility remains. A number of studies mention the increasing likelihood of electromagnetic interference if a device comes within 37.5 cm (~15 inches) of the CIED or lead wire.^{3, 7, 16}

“Minor” refers to non-clinically significant interference (noise, telemetry); “Severe,” to clinically significant outcomes (i.e., pacing disturbances or shock); “N.A.” (Not Applicable), no studies available.

A 2015 in-vivo prospective cohort study¹⁰ exposed 32 patients with CIEDs to a magnetostrictive scaler, an ultrasonic cleaning system, a curing light, electric toothbrush, and battery-operated pulp tester. They found minor electromagnetic interference when the scaler and cleaning system were less than 18 inches from CIED leads.¹⁰ Other asymptomatic minor interactions occurred with other devices at smaller distances but appeared to be interference with the monitoring devices (telemetry) and not the pacing or functioning of the CEID itself.¹⁰  This interference with telemetry and device monitoring has been argued to have been the cause of electromagnetic interference in a number of studies.^{5, 10, 23, 24}

There is evidence that piezoelectric scalers (commonly used in Europe) are safer than magnetostriction devices^{1, 19, 20}and may pose no risk to patients with CIEDs.^{4, 12, 13, 20, 25} A 2000 position paper²⁶ by the American Academy of Periodontology warned “[m]agnetostrictive ultrasonic scalers should not be used by clinicians or on patients with a pacemaker”²⁰ though this warning was later retracted.^{1, 3, 27}  Several in-vitro studies^{4, 6, 11} showed interference by magnetostrictive scalers though a 2013 in-vivo study found no interference between piezoelectric scalers and 5 different implantable cardioverter-defibrillator types in 12 patients.¹ A 2018 in-vivo study of piezoelectric scalers found only minor interference (noise) in telemetry, and no adverse events in pacemaker function.¹³

Apex locators and osseointegration monitoring tools have been found in in-vitro tests to be a low risk for light electromagnetic interference.^{2, 11}  However, in one in-vivo study, a symptomatic interruption of pacing was induced in patients by two brands of apex locators.⁸ A 2018 in-vivo study of an apex locator found only minor telemetry interference in 3.3% of patients.¹³

Although pulp testers were shown to be associated with “severe” electromagnetic interference (stimulation inhibition or inappropriate discharge) in in-vitro studies from 2015¹¹ and 2016,⁶ a number of other in-vitro studies found no interference,^{4, 10, 14, 22} nor was interference found in a 2015 in-vivo study.¹⁰ A 2018 in-vivo study found minor interference in telemetry in 7.5% of patients.¹³

Electrosurgical units are used to remove and cauterize tissue, and are available as monopolar (which requires an electrical current to pass through the patient’s body) and bipolar (in which the current is completed between two electrodes at the device tip) devices. In-vitro studies have consistently shown clinically significant electromagnetic interference to CIEDs from monopolar electrosurgery, including pacing interruptions and electrical shock.^{6, 14, 22}  The Heart Rhythm Society/American Society of Anesthesiologists published a consensus statement on management of CIED patients, which states that “[m]onopolar electrosurgery is the most common source of [electromagnetic interference] and CIED interaction in the operating room,”²⁸ and that head and neck region electrosurgeries using monopolar equipment “pose more of a risk for oversensing and damage to the CIED system.”²⁸

Battery-operated curing lights were shown to induce pacing inhibition in an in-vitro study in 2010,⁴ but more recent studies from 2015^{10, 22} did not result in any electromagnetic interference from curing lights. Ultrasonic cleaning systems were shown to produce significant electromagnetic interference in the 2010 study,⁴ and while minor interference with telemetry was encountered in the 2015 in-vivo study, pacing or sense functions were not affected.¹⁰ Both the 2010 and the 2015 studies found little or no risk from electric toothbrushes.^{4, 10}

Gutta percha heat carriers, but not guns, have been shown to produce electromagnetic interference in the form of background noise,^{2, 8} as well as cause an asymptomatic pause in an in-vivo study published in 2015.⁸ However, an in-vitro study in 2015 found no interference between gutta-percha devices and implantable cardioverter-defibrillators.²²

Although evidence is conflicting, consideration should be given to the possible effects ultrasonic or electronic devices could have on patients or staff who have implantable cardiac devices. Some manufacturers offer recommendations on use of their device in the vicinity of such implants, and reports of interference are from a dental device generally within 37.5 cm (~15 inches) to the device or leads. Dentists also may consult with the treating cardiologist to determine if ultrasonic or electronic devices can be safely used.  If ultrasonic or electronic dental devices (or other such equipment) are used, it may help reduce the risk to avoid waving the device or its cords over the patient’s pectoral region, and turn off this equipment when not in use.

1. Maiorana C, Grossi GB, Garramone RA, Manfredini R, Santoro F. Do ultrasonic dental scalers interfere with implantable cardioverter defibrillators? An in vivo investigation. J Dent 2013;41(11):955-9.
2. Dadalti MT, da Cunha AJ, de Araujo MC, de Moraes LG, Risso Pde A. Electromagnetic interference of endodontic equipments with cardiovascular implantable electronic device. J Dent 2016;46:68-72.
3. Pisano P, Jr., Mazzola JG, Tassiopoulos A, Romanos GE. Electrosurgery and ultrasonics on patients with implantable cardiac devices: Evidence of side effects in the dental practice. Quintessence Int 2016;47(2):151-60.
4. Roedig JJ, Shah J, Elayi CS, Miller CS. Interference of cardiac pacemaker and implantable cardioverter-defibrillator activity during electronic dental device use. J Am Dent Assoc 2010;141(5):521-6.
5. Misiri J, Kusumoto F, Goldschlager N. Electromagnetic Interference and Implanted Cardiac Devices: The Medical Environment (Part II). Clinical Cardiology 2012;35(6):321-28.
6. Miranda-Rius J, Lahor-Soler E, Brunet-Llobet L, Sabate de la Cruz X. Risk of electromagnetic interference induced by dental equipment on cardiac implantable electrical devices. Eur J Oral Sci 2016;124(6):559-65.
7. Tom J. Management of Patients With Cardiovascular Implantable Electronic Devices in Dental, Oral, and Maxillofacial Surgery. Anesthesia progress 2016;63(2):95-104.
8. Moraes AP, Silva EJ, Lamas CC, Portugal PH, Neves AA. Influence of electronic apex locators and a gutta-percha heating device on implanted cardiac devices: an in vivo study. Int Endod J 2016;49(6):526-32.
9. Baddour LM, Epstein AE, Erickson CC, et al. A summary of the update on cardiovascular implantable electronic device infections and their management: a scientific statement from the American Heart Association. J Am Dent Assoc 2011;142(2):159-65.
10. Elayi CS, Lusher S, Meeks Nyquist JL, et al. Interference between dental electrical devices and pacemakers or defibrillators: results from a prospective clinical study. J Am Dent Assoc 2015;146(2):121-8.
11. Lahor-Soler E, Miranda-Rius J, Brunet-Llobet L, Sabate de la Cruz X. Capacity of dental equipment to interfere with cardiac implantable electrical devices. Eur J Oral Sci 2015;123(3):194-201.
12. Stoopler ET, Sia YW, Kuperstein AS. Does ultrasonic dental equipment affect cardiovascular implantable electronic devices? J Can Dent Assoc 2011;77:b113.
13. Conde-Mir I, Miranda-Rius J, Trucco E, et al. In-vivo compatibility between pacemakers and dental equipment. Eur J Oral Sci 2018;126(4):307-15.
14. Sriman N, Prabhakar V, Bhuvaneswaran JS, Subha N. Interference of apex locator, pulp tester and diathermy on pacemaker function. J Conserv Dent 2015;18(1):15-9.
15. U.S. Food and Drug Administration. Magnets in Cell Phones and Smart Watches May Affect Pacemakers and Other Implanted Medical Devices. Washignton, D.C.: U.S. Food and Drug Administration; 2021.
16. Lacour P, Parwani AS, Schuessler F, et al. Are Contemporary Smartwatches and Mobile Phones Safe for Patients With Cardiovascular Implantable Electronic Devices? JACC Clin Electrophysiol 2020;6(9):1158-66.
17. Asher EB, Panda N, Tran CT, Wu M. Smart wearable device accessories may interfere with implantable cardiac devices. HeartRhythm Case Rep 2021;7(3):167-69.
18. Shea JB, Aguilar M, Sauer WH, Tedrow U. Unintentional magnet reversion of an implanted cardiac defibrillator by an electronic cigarette. HeartRhythm Case Rep 2020;6(3):121-23. 
19. Gomez G, Jara F, Sanchez B, Roig M, Duran-Sindreu F. Effects of piezoelectric units on pacemaker function: an in vitro study. J Endod 2013;39(10):1296-9.
20. Trenter SC, Walmsley AD. Ultrasonic dental scaler: associated hazards. J Clin Periodontol 2003;30(2):95-101.
21. Idzahi K, de Cock CC, Shemesh H, Brand HS. Interference of electronic apex locators with implantable cardioverter defibrillators. J Endod 2014;40(2):277-80.
22. Maheshwari KR, Nikdel K, Guillaume G, et al. Evaluating the Effects of Different Dental Devices on Implantable Cardioverter Defibrillators. Journal of Endodontics 2015;41(5):692-95.
23. Crossley GH, Poole JE. More about pacemakers. J Am Dent Assoc 2010;141(9):1053; author reply 53-4.
24. Patel D, Glick M, Lessard E, Zaim S. Absence of in vivo effects of dental instruments on pacemaker function. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology 2005;99(4):430.
25. Kamal R, Dahiya P, Saini H. Dental treatment in patients with cardiac pacemakers: Is it a risky affair? Journal of Dental Research and Review 2016;3(2):76-78.
26. Drisko CL, Cochran DL, Blieden T, et al. Position paper: sonic and ultrasonic scalers in periodontics. Research, Science and Therapy Committee of the American Academy of Periodontology. J Periodontol 2000;71(11):1792-801.
27. Position paper update. J Periodontol 2007;78(8):1476.
28. Crossley GH, Poole JE, Rozner MA, et al. The Heart Rhythm Society (HRS)/American Society of Anesthesiologists (ASA) Expert Consensus Statement on the perioperative management of patients with implantable defibrillators, pacemakers and arrhythmia monitors: facilities and patient management. Heart Rhythm 2011;8(7):1114-54.

Professional Resources

• ADA Library Services
• ADA Store: The ADA Practical Guide to Patients with Medical Conditions (Item #P031)

Patient Resources

• ADA MouthHealthy.org: A-Z Topics: Pacemakers
  
  

American Heart Association Resources:

• Devices that may interfere with Pacemakers
• Devices that may interfere with Implantable Cardioverter Defibrillators

Journal of the Canadian Dental Association 

• Does ultrasonic dental equipment affect cardiovascular implantable electronic devices?