Press Releases

Notification of Incident at Tan Tock Seng Hospital Dental Clinic

10 December 2018

  1. The Tan Tock Seng Hospital (TTSH) Dental Clinic has discovered that eight packs of instruments prepared for sterilisation did not undergo the last step of sterilisation and may have been used for outpatient treatment at the clinic. Up to eight patients who visited the clinic between 28 November and 5 December may have received treatment using the affected instruments.
  2. Background of Incident

  3. At TTSH, the process for the sterilisation of dental instruments prior to usage comprises the following steps:
    • Step 1: Manual wash and then ultrasonic machine sonication with enzymatic solution for fine instruments.
    • Step 2: The instruments are then air dried to remove residual moistures and then packed, sealed and labelled. At this stage, close to 100% of organisms of concern would have been eradicated.
    • Step 3: As a final step, the sealed instruments are put through an additional process of steam sterilisation to remove bacterial spores.
  4. On 4 December, a TTSH Dental Clinic staff found a dental instrument that had not gone through the final step of steam sterilisation. Following a check of all dental instruments on 5 December, it was found that eight packs of instruments that were processed on 28 November had not completed the last step of the sterilisation process and had been used for patient treatment at the TTSH Dental Clinic.
  5. Risk of Infection Assessed to be Extremely Low

  6. The risk of infection to patients arising from this incident is assessed to be extremely low given that the completion of the earlier steps in the sterilisation process would have removed close to 100% of organisms of concern. Nevertheless, we are contacting all 575 patients who had been treated at the dental clinic during the affected period to reassure them on their low risk of infection, provide support and address any concerns.
  7. Associate Professor Thomas Lew, Chairman Medical Board, TTSH, said, "We sincerely apologise to our patients and their families for the lapse and distress caused. We are contacting the patients who received treatment during the affected period. Additional measures are in place to bolster and improve our vigilance and workflows to ensure the wellbeing and safety of all our patients."
  8. Patients who have any queries can call hotline number: 6256 6011.
  9. Thorough Reviews of Incident to be Conducted

  10. Learning from a previous incident at the National Dental Centre Singapore (NDCS) in June 2017, the TTSH Dental Clinic had put in place several improvement measures over the past year. These include revising pouching and documentation procedures, partitioning functional work areas, and instituting that completion of the sterilisation process be verified by two staff. TTSH Dental Clinic staff were also required to undergo a new competency assessment, and sent for training and certification at TTSH’s central sterile supply department (CSSD).
  11. In December 2017, the Ministry of Health had conducted an inspection of TTSH’s CSSD. The TTSH Dental Clinic also underwent biannual audits on their sterilisation procedures in May 2017, November 2017, May 2018 and October 2018. There were no procedural or equipment gaps found during these audits. In addition, the TTSH Dental Clinic underwent an inspection by the Joint Commission International (JCI), which found its processes to be in conformance with standards.
  12. This incident shows however that further improvements are necessary. TTSH and the National Healthcare Group are conducting thorough reviews. As a precautionary measure, elective procedures at the Dental Clinic have been suspended since 8 December to allow a safety time-out. Meanwhile we have put in place added controls at the Dental Clinic, and reinforced efforts to heighten staff awareness and full adherence to our processes for patient safety and care across the entire hospital. Elective outpatient dental services will resume from 12 December.