The Centers for Disease Control and Prevention (CDC) is recommending treating dental unit waterlines and monitoring water quality after multiple outbreaks of nontuberculous Mycobacteria (NTM) infections in children who received pulpotomies.
The procedure involves repairing cavities or damage to primary (baby) teeth, and dental waterlines contaminated with bacteria previously have caused such infections. The small-bore plastic tubing provides water to dental equipment, such as high-speed handpieces.
“Biofilms occur in dental unit waterlines due to the long, small-diameter tubing and low flow rates used in dentistry and the frequent periods of stagnation,” the CDC reports.1 “As a result, high numbers of common waterborne bacteria can be found in untreated dental unit water systems. Disease-causing microorganisms found in untreated dental unit water can include Legionella, Pseudomonas aeruginosa, and NTM.”
In March 2022, the CDC was notified of a new cluster of suspected NTM infections in children following dental procedures at a pediatric dental clinic. Investigation into this cluster currently is ongoing, and preliminary site visit data report that dental unit waterline testing results showed microbial counts much higher than the level recommended by CDC.
Previous outbreaks have involved young children, with ages ranging from 4 to 8 years.
“Many of the children developed severe infections with clinical diagnoses, such as cervical lymphadenitis and mandibular or maxillary osteomyelitis, and required hospitalization, treatments such as intravenous antibiotics and surgical procedures,” the CDC reported. “Complications from their infections included permanent tooth loss, hearing loss, facial nerve palsy, and incision fibrosis.”
Given the severity of these infections, the CDC recommends that providers assess the history of dental care in all children presenting with lymphadenitis.
“During a healthcare-associated outbreak investigation of NTM infections of the head and neck region, assess patients for a history of recent dental treatment,” the CDC recommends.
Because of the potential to form biofilm, the CDC recommends that all dental unit waterlines be treated regularly with disinfectants that to meet the Environmental Protection Agency regulatory standards for drinking water (i.e., ≤ 500 colony-forming units/mL of heterotrophic water bacteria).
“There are many commercial products and devices available to disinfect and maintain dental unit waterlines,” the CDC said. “Dental unit water quality must also be monitored routinely as recommended by the equipment manufacturer to ensure that treatments are working effectively and that the water used in dental procedures meets safety standards.”
- Centers for Disease Control and Prevention. Outbreaks of nontuberculous Mycobacteria infections highlight importance of maintaining and monitoring dental waterlines. Published Oct. 31, 2022. https://emergency.cdc.gov/han/2022/han00478.asp
