An elderly patient saw a DDU member for a restoration because of caries. The dentist removed the caries, but as he was finishing the cavity with a high-speed hand piece, the bur came into contact with the floor of the patient's mouth and caused a laceration.
Our member stopped the procedure immediately and informed the patient. He applied pressure with gauze and cotton wool swabs, but as the patient was on warfarin - an anticoagulant medication - it was not possible to entirely halt the bleeding.
The member contacted the maxillofacial registrar at the local hospital for advice, and the patient was referred there, where she had sutures placed before being sent home. She reattended hospital later in the evening, where she underwent further suturing and was admitted overnight for observations before being discharged the following day. The laceration healed well.
The patient brought a claim that alleged our member had been negligent in causing the laceration, as he had let the drill 'slip', failed to control the bur, failed to adequately protect the soft tissues and failed to suture the wound or otherwise achieve haemostasis.
The crux of the case was the factual dispute between the member and patient as to how the injury had occurred. The member firmly held that the patient had swallowed and moved suddenly as a result, which caused the bur to come in contact with the soft tissues.
Unfortunately, it had not been recorded in the records that the patient had moved, but our member's account was very clear and was supported by the assisting dental nurse, who recalled the incident and helpfully provided a statement. The patient maintained that he had not moved.
As the patient was on warfarin - an anticoagulant medication - it was not possible to entirely halt the bleeding.
The DDU obtained independent expert evidence that was supportive of the member's treatment, while recognising the factual dispute. On behalf of the member, the DDU sent a letter of response denying liability, but the patient's solicitors refused to drop the case and served court proceedings.
We instructed one of our panel firms of solicitors and continued to robustly defend the case throughout proceedings. When the experts from both sides of the case met, they agreed it hinged on the factual dispute - because if the patient had in fact moved, there had been no breach of duty by our member.
The case continued until a week before trial, when the patient's solicitors finally discontinued.
Cases that centre around a factual dispute can be difficult to defend, but it was our view throughout that the member's evidence, supported by the nurse's evidence, would be preferred over the patient's at trial.
When a patient swallows, the floor of the mouth will rise up and the soft tissues will then be at the level of the lower teeth. If this happens unexpectedly - which happens not infrequently - the practitioner can't always react quickly enough to stop the drill. In such circumstances, it is not always possible to prevent the tongue or soft tissues of the floor of the mouth from coming into contact with the drill and hence being damaged.
Given that the dentist is working in such a small space with high-speed tools, such injuries to the intra-oral soft tissues could occur at any appointment, even when all reasonable skill and care are used and all reasonable measures to reduce the risk of injury are applied. Patients can move unexpectedly, and there can be difficulty with control of tongue movements and swallowing.
However, such injuries can also be caused by carelessness or lack of attention by the dental professional, which would amount to a breach of duty.
It is imperative that dental professionals and assisting nurses are careful and use the dental mirror or other appropriate instruments as well as the aspirator to retract and protect the soft tissues.