Report on case where dentist removed all of woman's bottom teeth by accident

As if straight out of a Monty Python sketch, New Zealand's Health and Disability Commission has issued final opinion on a women who had all of her bottom teeth removed by accident.

Names have been removed to protect the innocent. Identifying letters are assigned in alphabetical order and bear no relationship to the person’s actual name.

On 8 November 2002, Ms A attended an appointment with Dr B and Mr D, a clinical dental technician. During this consultation, Dr B and Mr D discussed with Ms A the options for treatment. There is dispute as to whether a full clearance of Ms A’s lower teeth was discussed. It is not recorded in the clinical records.

At that consultation it was agreed that Ms A would have four lower incisors removed later in the month.

Dr B advised me that “of course an X-ray was suggested when Ms A returned for treatment in 2002”, but Ms A denies this stating “at no stage was an X-ray suggested. Dr B just put up the X-ray that was taken in 2000 and made no comment about requiring a new one.” The suggestion of a further X-ray is not documented.

On 14 November, Ms A had an appointment with Mr D, where he took impressions to make a partial plate for her lower four incisors.

On 28 November, Ms A returned to the surgery for the extractions. Mrs C, dental assistant, brought up Ms A’s records on the computer in the surgery. She then brought through Ms A from the waiting room. Ms A told her that she was nervous about the treatment. Ms A said that when she was taken into the surgery she “saw the image on the screen with 4 X’s where the extractions were to be made”.

Dr B advised me that he consulted the records on the screen page called ‘Details’ and then sighted medical history details. He then reviewed the scanned IV sedation consent on the computer and finally loaded the treatment page with two different treatment plans. He then double clicked the IV sedation treatment code box to open it and record baseline parameters for IV sedation.

Ms A then signed the consent form for her intravenous (IV) sedation, prior to treatment. Dr B states that he would normally check lab-work (in this case the partial plate) the night before an appointment. However, in this case, Ms A’s plate did not arrive until lunchtime on 28 November and he did not check it at the start of the procedure.

Prior to beginning treatment Dr B asked Ms A the usual question he asks all patients who will have IV sedation: “Do you know what we are going to do?”, or words to that effect. Ms A recalls that she replied, “Clean the lower teeth, extract the four lower teeth and fit the plate”, or words to that effect. Dr B’s recollection is that Ms A said “these teeth”, not “four teeth”. He believes he repeated her answer, “all of the teeth”, to Ms A and she agreed.

Ms A’s recollection is that Dr B did not repeat what she said. Mrs C states that she did not hear Ms A clearly say “just four teeth”, but said that she found it hard to understand clearly what Ms A said. Mrs C believes she heard Dr B say the word “all”, to which Ms A agreed.

Dr B then sedated Ms A and began the procedure. During the procedure Mrs C asked why he was cleaning Ms A’s teeth prior to extracting them. Dr B explained that it lessened the risk of infection. He added that he would need a lower molar instrument to extract some of the teeth. Mrs C then obtained this instrument from a nearby cupboard.

Dr B advised me that although Ms A’s teeth had no fillings or decay, their periodontal health was poor and the extractions were easy to perform. Ms A stated that following the extraction her face and jaw were severely bruised.

After the extraction, when Ms A woke up, they discussed what had happened. During this discussion Ms A said that she had wanted only the four incisors taken out. Dr B replied that this was not what he had heard. Nonetheless, on observing the plate that was to be fitted, Dr B realised his error.

In response to Commision's provisional opinion, Dr B made the following submissions:

I accept that I did not see the records stating that four teeth were to be extracted, however I do not accept your statement that I failed to check the treatment plan or other notes. After [Mrs C] brought [Ms A’s] records onto the computer screen (which is in the surgery two, my practice has four surgeries and six linked computers on our Local Area Network), I certainly did consult the records on the screen page called Details and then sighted medical history details.

I then reviewed the scanned IV sedation consent on the computer (this was recorded on another page so I had to physically open it at the time, clicking on the tab with the mouse) and finally loaded up the treatment page with two different treatment plans. I then double clicked the IV sedation treatment code box to open it and record baseline parameters for IV sedation.

In our clinical management software package, ‘Exact’, a user has to use the mouse and/or keyboard to change from data fields and for each patient record. There are up to seven full screens of patient data (more for scanned documents or referral letters). I viewed three of [Ms A’s] patient record screens at the beginning of the consultation prior to confirming the procedure with her verbally.

The panorex x-ray was mounted on the viewer in the surgery. When I viewed it I noted the bone loss around the lower anteriors and posterior molars and the impacted upper canine tooth.

The principal fact is that I misheard [Ms A’s] verbal consent, twice. My initial question to her was open-ended, in that I asked [Ms A] to tell me what she expected we were going to do. Thinking she had said we were to remove ‘all of the teeth’ I repeated this back to her, and she agreed with me. I then established that [Ms A] wanted to retain the upper canine tooth.

Accordingly, this was not a case of forging ahead with a procedure with absolutely no consideration of patient notes, or no discussion with the patient.

I sedated [Ms A] via an IV cannula in the right ante-cubital fossa by slow titration. Then I administered local anaesthetic in the mouth (left and right inferior dental blocks both with separate injections of Lignocaine and Marcaine). After administering local anaesthetic but prior to extraction I examined [Ms A’s] mouth and noted gross calculus, very poor gum health and that the majority of her teeth were splinted by calculus. In my own mind, this confirmed that a full lower extraction was reasonable.

While waiting for the local anaesthetic to work, I recorded my understanding of the verbal consent by activating the relevant treatment codes (by ticking on the relevant treatment code tick boxes, by clicking box with mouse) ‘Full Clearance Per Arch’ and ‘Full Lower Denture’. I then entered further intravenous sedation parameters into the ‘IV sedation’ text box template.

After the extractions, while waiting for haemostasis after suturing, I charged these three items through. … This is our normal practice as the escort often pays the bill (as per our sedation consent) because the patient is unfit for business transactions. Additional clinical notes are added in treatment code ‘notes’. When I went to fit the plate after haemostasis my initial thought was that the wrong plate had been supplied. I then realised that the error was mine.

The full report can be found here: http://www.hdc.org.nz/files/pageopinions/02hdc18228dentist.pdf