Hyland v Huen [2003] ACTSC 70 (3 September 2003)

Last Updated: 14 October 2003

CHRISTINE JOY HYLAND v DR KAI HUEN

[2003] ACTSC 70 (3 September 2003)

MEDICAL NEGLIGENCE - dental treatment - extraction of upper left molar - excessive force - failure to warn of risk of infection.

DAMAGES - personal injuries - ankylosis of temporomandibular joint - assessment - no issue of principle.

FGT Custodians Pty Ltd v Fagenblat [2003] VSCA 33

Rosenberg v Percival [2001] HCA 18, (2001) 205 CLR 434

No SC 76 of 2002

Judge: Connolly J

Supreme Court of the ACT

Date: 3 September 2003

IN THE SUPREME COURT OF THE )

) No SC 76 of 2002

AUSTRALIAN CAPITAL TERRITORY )

BETWEEN: CHRISTINE JOY HYLAND Plaintiff

AND: DR KAI HUEN

Defendant

ORDER

Judge: Connolly J

Date: 3 September 2003

Place: Canberra

THE COURT ORDERS THAT:

1. There be judgment for the plaintiff in the sum of $139,208.95 with costs.

1. This is a claim for damages for personal injuries, which are said to arise from negligent medical treatment provided by the defendant, a Canberra dentist. The plaintiff's claim is that when she attended with a complaint of a toothache on 21 February 1996 the defendant extracted her upper left third molar negligently by applying inappropriate force, causing damage to her left temporomandibular joint, being the jaw joint, leading to an ankylosis, or fusing, of that joint, requiring surgical intervention.

2. It is common ground that the plaintiff has experienced ongoing significant difficulties with her left temporomandibular joint, and that there was some form of frank disruption to the structure of this joint that was diagnosed shortly after the extraction of the tooth. It was common ground that damage to the joint lead to ankylosis, or fusion, of the jaw joint, which has required surgical intervention and ongoing invasive treatment. The real issue between the parties at the hearing was whether the cause of the plaintiff's ongoing problems with her left temporomandibular joint was due to negligent dental treatment by the defendant.

3. The plaintiff pleaded her case against the defendant on two grounds. The primary case was based on an allegation of excessive force being used. The secondary basis was of a failure to warn of a risk of infection from the removal of a badly decayed tooth. This secondary ground assumed significance in the case because the defendant's principal expert, who was the plaintiff's treating specialist, strongly disagreed that the type of force used to extract a tooth could damage the temporomandibular joint, and expressed the view that the most likely cause of the damage to the joint was an infection caused by the release of a "shower of bacteria" when the badly decayed tooth was extracted. The plaintiff gave evidence that had she been advised of a risk of damage from infection by the badly decayed tooth, she would have sought antibiotic cover. The plaintiff is a trained nurse.

4. The plaintiff says that she noticed toothache on the left side of her face on about 19 February 1996, and she made an appointment to see her local dentist, Dr Gallagher, which resulted in her attendance upon the defendant on 21 February. She says that she was told that Dr Gallagher was not available, but that she could see the defendant, who was a locum. The defendant was an experienced general practice dentist, who was then employed at Dr Gallagher's surgery. The plaintiff had not previously been treated by the defendant, but had attended at the practice.

5. Her evidence was that she had arranged a number of events on that day, including a coffee meeting in the morning and lunch with friends, and an afternoon appointment at her daughter's school. She says that when she attended the surgery and was shown to the defendant's room she told him that she had a toothache on the left side of her face, and the defendant said that he would take an x-ray to have a look at the teeth. This was done, and the x-ray was in evidence before me. The x-ray showed the decay in the tooth but it did not show the root structure of the tooth which was removed, although it did show the root structure of the healthy lower teeth.

6. The plaintiff says that the defendant told her that her upper left wisdom tooth was "quite decayed" and that it needed to be removed. In his evidence the defendant says that the plaintiff complained of an upper left toothache, and that on examination the "obvious cause was the very decayed upper left third molar". The plaintiff says that she told the defendant that she had a number of appointments that day, and that he said that the tooth needed to be removed, and she agreed to this procedure.

7. She says that she was not given any material to read relating to the extraction of a tooth, and was not told anything about the risks that might be associated with the extraction of a tooth. It is common ground that no warnings in relation to either traumatic damage to the jaw joint or the risk of bacterial infection from the removal of a decayed tooth were given.

8. The plaintiff says that she was then given an injection to her upper jaw area by way of an anaesthetic, and when her upper left area was numb, the defendant told her to open her mouth, and introduced an instrument to her mouth. In his evidence the defendant described the normal procedure that he uses to extract this tooth, which involved the use of an instrument called an elevator, which is a narrow instrument inserted between the upper third molar and the tooth in front of it, and is then twisted to move the third molar backwards and forwards to loosen the tooth. The elevator is not dissimilar in appearance to a screwdriver. The defendant acknowledged that he had no clear recollection of performing the procedure on the plaintiff, but described his normal practice.

9. The plaintiff says that she was aware of "lots of crunching and grinding carrying on". She says that forceps were applied and "I was actually pulled forward out of the chair". She says that her "head and probably the top of my shoulders" were pulled forward from the chair when the defendant was pulling on the forceps. She says that she was trying to yell and was waving her hands trying to tell him to stop, but he did not stop.

10. The defendant said that sometimes the use of the elevator was sufficient to extract the tooth, but that sometimes forceps would be used. He said that when forceps are used, the forceps would clamp around the crown of the tooth, and the motion would be to rock the tooth towards the cheek and back again. The defendant demonstrated this action in court. He described and demonstrated a lateral movement, and not a movement pulling the tooth directly out in such a way that the force would pull the patient up from a chair.

11. The plaintiff impressed me as a truthful witness, and indeed it was not suggested by counsel that she was doing anything other than describing her best recollection of events. The defendant, when asked about her evidence that her head was pulled forward in the chair, was more vehement, describing this as "a physical impossibility, and a fabrication" (T 118). I reject the proposition that the plaintiff has fabricated any evidence, and I find her to be a witness of truth.

12. The defendant did not deny that the plaintiff told him to stop the procedure, although he said that he had no recollection of this and had made no note of it. It was put to him by his counsel that the plaintiff said that she asked him to stop after hearing a crunching sensation, and he said (T 118) -

That would be likely to be buccal plates of bone breaking which is quite common in the extraction of a tooth. Or it could be the tooth crumbling because the tooth was very decayed to start off with, and when you apply the elevator to the tooth, sometimes the tooth will crumble, being weak.

13. The defendant later said in cross-examination that he did not dispute that the plaintiff made some noises and waved her hands around during the course of the extraction to get him to stop (T 122).

14. The plaintiff says that after her protest the defendant stopped and reassured her that there was nothing wrong, and told her that the tooth was nearly out, and she should lie back and relax. This is consistent with his evidence as to how he would normally perform the procedure. She says that he recommenced, and shortly after her tooth was removed. She says that she felt faint and sweaty as she attempted to get out of the chair, and that she then lay back for a while before leaving the surgery.

15. At this time her jaw was still numb from the anaesthetic. She says that the next day, when she attempted to eat a cheeseburger, she was unable to open her mouth wide enough. She says that she continued to experience pain in the jaw, and was unable to open her mouth properly, and she took some Panadine. After a few days she made an appointment to see her general practitioner, Dr M Langtry. She says that the symptoms at that time were of a quite painful left ear. Dr Langtry's notes, which were tendered in the defendant's case, show that this was the presenting complaint, but it is clear that the dental visit was discussed, as the notes record "?? dental problem". Dr Langtry prescribed Augmentin Forte, a broad spectrum antibiotic on the visit of 26 February 1996, which is some five days after the tooth was removed.

16. The plaintiff continued with pain in her left ear region and difficulty with opening her mouth, and she attended another dentist, Dr G Labour, on 28 February 1996. He noted clicking in the jaw, and prescribed heat therapy and anti-inflammatory medication. On her next visit on 6 March 1996 Dr Labour prescribed a splint to improve jaw movement, and this was continued with and variously adjusted through March. In April 1996 the plaintiff was referred by her brother, who is a general practitioner, to Dr P Vickers, an oral and maxillo-facial surgeon. He provided treatment, and reported to the plaintiff's solicitor in May 1997. This report, which was tendered in the defendant's case, said in part -

... for the previous two months prior to my appointment with her she suffered trismus (inability to open the jaw properly). When we saw Mrs Hyland her jaw opening was 8 mm passive and 15 mm forced. Lateral movements were also diminished and we indicated to her that possibly she should have a jaw x-ray to confirm that there was no obvious reason for the trismus, physiotherapy, Normison (muscle relaxant), and to continue with the dental splint that had been prescribed by Dr Gilbert Labour, dental surgeon. On April 16, 1996, we gave Mrs Hyland sedation in our office and noted at the time that manipulating her jaw she could open to 35 mm. Once the sedation had worn off her jaw opening was 25 mm. We then sent her for an MRI scan of her jaw joints since our provisional diagnosis was anterior disc displacement without reduction. MRI scans confirmed bilateral disc displacement and on May 1, 1996, we proceeded to arthrocentesis in our office of the superior joint space on the left and right temporomandibular joints.

Subsequent to this she was referred to Dr Noel Egan and Dr Egan has continued with the splint therapy.

17. After describing the treatment and findings, Dr Vickers opined -

In discussions with Dr Kai Huen and Dr Gilbert Labour and perusal of their notes it is apparent that Mrs Hyland has been treated appropriately by the initial dentist who extracted the upper left wisdom tooth. There is no evidence to support that the treatment by Dr Huen was inappropriate, and indeed there is also no evidence to indicate the connection between the upper left wisdom tooth and her temporomandibular joints.

18. Dr Egan continued treatment by way of adjusting the splints and ongoing chiropractic adjustments, but these failed to provide significant relief through the balance of 1996, and during most of this time the plaintiff was absent from her work as a nurse. She returned to work in February 1997,and was referred in that month by Dr Egan to Professor JE Norman AO (Clinical Professor) and Dr NJ Peppitt in Sydney, who eventually recommended and performed surgery. On 4 June 1997 Professor Norman performed a left temporomandibular arthroplasty with a resection of the ankylosis, or fused part of the joint.

19. In a report of 13 May 1998 to the plaintiff's solicitors, but tendered in the defendant's case, Professor Norman said -

It is the writer's belief that physical trauma was most unlikely to have been the cause [of the damage to the joint].

He repeated this view in a further report of 10 December 1998 where he said -

It is not the writer's belief that excess force during the extraction of an upper third molar tooth would have given rise to a temporomandibular ankylosis and this referring to the ankylosis between the ball of the jaw joint and its socket in the temporal bone.

He also said in that report that -

The question arises as to whether the physical trauma of the extraction of an upper molar tooth under local anaesthesia in an adult woman would give rise to an ankylosis and the writer is unable to provide you with an explanation as to how this might occur and it would appear to be improbable in the extreme.

20. Dr Peppitt, who assisted Professor Norman in the surgery, has reported on 4 November 1999 that -

Any extraction requires force and it is highly possible that the force applied to the jaw initiated Mrs Hyland's subsequent problems. Certainly in the history a cause/effect relationship exists.

21. The strongest support for the claim that the problems that the plaintiff has undoubtedly experienced since the time of the extraction were caused by the extraction comes from Dr Egan. In a report of January 1997 he said -

It would seem to me that, as Christine had no discomfort and no limited jaw movement up until the appointment for the extraction and has since then not been able to open her mouth then a direct connection has been established between the experience and the extraction and the problems that she now encounters.

As to whether the extraction was performed negligently or not is something you would have to establish within legal parameters.

In an earlier report of December 1996 he said -

I do believe that there is a definite connection has been established between Christine's discomfort and limited movement and the extraction and I would have to report that this is a most unusual and persistent response to the removal of an upper third molar.

22. Dr Egan's views were challenged by counsel for the defendant. Dr Egan acknowledged in his report to the plaintiff's solicitors of February 1997 that -

As I noted in my previous letter to you I do not do any extractions at all and so I am not really in a position to provide an opinion on the nature of a procedure and the way such a procedure would normally be carried out.

23. The defendant makes the point that the only report that asserts a positive link between the extraction and the joint damage is from an expert who acknowledges that he does not do extractions, and is not in a position to provide an opinion on the nature of the procedure.

24. The defendant tendered a series of letters from Dr Egan to Professor Norman and Dr Peppitt in which Dr Egan appears to have moved from acting as an impartial expert to acting as an advocate for the plaintiff, and indeed to request the other experts to modify or reconsider their opinions. In a letter to Professor Norman of 23 April 1999, after his report to the plaintiff's solicitors, Dr Egan said -

John, as you know, Christine's case for recompense would fail miserably if you do not support her and I am asking you therefore if you might reconsider this opinion in the light of the following facts.

25. He then goes on to set out arguments against Professor Norman's expressed view that an infection was the more likely cause of the plaintiff's difficulties. The letter continues -

As you know, John I am somewhat prejudiced about this case of Christines. I do believe she has been treated rather badly by our profession and that some recompense is not unreasonable.

.........

I am not looking for a scapegoat but I believe somewhere along the line there must be some way she can get some recompense. I do believe she has no avenue if you withdraw support for her case and it is because of this that I sincerely ask you to reconsider the possibility that the damage has occurred other than through any infective root. I do not believe the evidence supports such a hypothesis.

Would you please mind reviewing your assessment of this matter.

26. Dr Egan followed this up with another letter in June 1999 again asking Professor Normal to reconsider his views. Professor Norman did not respond to Dr Egan, and indeed quite properly wrote to the plaintiff's solicitor in May 1999 saying -

As an experienced attorney, ... you are cognisant of the fact that it is inappropriate for the writer to discuss the medico-legal aspects of this matter with his colleague, Dr Noel Egan.

27. Dr Egan also wrote to Dr Peppitt on March 12 1997 and said -

You should know that Christine has looked at the possibility of recovering some of the costs through the process of litigation however at this stage of the game she does not seem to be progressing this as it seems difficult to find a dentist who will support the obvious claim that the extraction should not have been performed without a periapical x-ray of the tooth in question.

28. The action of Dr Egan in writing to Professor Norman and asking him to modify his opinion in order to assist the plaintiff is conduct that must be regarded by this Court as quite inappropriate. There have been conscious efforts in recent years to change the legal culture where experts might be regarded as "hired guns" to a culture where experts see their duty as primarily to the Court, and not as partisans or advocates. An expert witness code of conduct has been in place in the Supreme Court of New South Wales since 2000, and in identical terms in this Court since May 2003 (Practice Direction 3 of 2003), and this states clearly that "An expert witness is not an advocate for a party". Dr Egan has clearly acted as an advocate for the plaintiff, and his sympathy for her difficulties has lead him to the quite inappropriate actions of urging Professor Norman to change his opinion that trauma at the time of the extraction was not the cause of her problems.

29. The Victorian Court of Appeal has recently restated the important duty the expert owes to the Court. In FGT Custodians Pty Ltd v Fagenblat [2003] VSCA 33 the Court was asked to exclude the evidence of an expert for perceived bias. The Court, per Ormiston JA, said at [8] that bias has never been a basis for the exclusion of expert evidence -

whatever one might have said as to the wisdom of calling him as an expert in this action and whatever one may say as to the ultimate decision to prefer his evidence.

30. The primary way in which the plaintiff's unquestioned jaw problem is linked to the treatment provided by the defendant is the argument that the extraction was so forceful that the trauma of the extraction caused damage to the jaw. Dr Egan is the principal exponent of this, but he acknowledged that he does not do extractions and has not done so for some time, and so his capacity to provide expert evidence on this point must be called into question, even without taking into account the issues of his clear partiality and role as advocate for the plaintiff.

31. The balance of expert opinion in the hearing seems to favour the proposition that the defendant was negligent in not ensuring that the x-ray that he took showed the root of the tooth to be extracted. However, this negligence can only sound directly in damages if it is established, on the balance of probabilities, that the failure to follow appropriate practice was the cause of the injury, and this would only follow if it is shown that the jaw was damaged due to trauma from excessive force used to remove the tooth.

32. The plaintiff has given evidence that she recalls her head being pulled forward in the chair, and I have previously said that I found that she was an honest witness. The defendant demonstrated the method that he says he would always use to remove a tooth, the method endorsed by other specialists, and it is apparent that the forces applied in this would not lead to the patient's head being pulled forward in the chair. I accept that the plaintiff would have heard crunching, as she described it, probably, on the defendant's evidence, from the decayed tooth breaking up, and that she no doubt detected and experienced some movement of her head, but despite her honest belief, I am not satisfied that this would have involved a movement up and away from the seat.

33. Dr Peppitt expressed the view in his report that it was "highly possible" that the damage to the plaintiff's jaw was caused by the extraction, and in his evidence-in-chief he said that by this he meant that on the balance of probabilities the most likely cause of the damage was trauma. In cross-examination he was asked whether it would be possible for trauma to the jaw to occur through the standard extraction process, and he said (T 73) -

... if extraction forceps were used there's always a chance of any surgery in the mouth, causing trauma to the joint, whether it's been from opening the jaw too wide or from pushing the jaw to one side, there's always that possibility.

34. He said that this could occur from quite minor trauma, although this would be "really unusual" (T 74). He was then asked whether this was exceptionally unusual, and he said (T 74) -

It's - ankylosis of the temporomandibular joint is almost non- existent, in my practice. I've never seen it before. Maybe once, and that's in 20 odd years of seeing people with temporomandibular joint problems, with all sorts of traumatic conditions.

35. It seems to me that Dr Peppitt's evidence goes to show that he feels that it is more likely that the jaw damage was done by trauma than by infection, and that it could be caused by relatively minor trauma, but that it is a very unusual condition. He does not offer a view on whether the defendant's extraction caused the damage or whether the defendant used excessive force. Indeed, it follows from Dr Peppitt's evidence that this condition could result from perfectly normal pressure being applied, as an unlikely but unfortunate medical misadventure.

36. The principal evidence from the defendant's case against any link between the defendant's treatment and the ankylosis of the joint was Professor Norman, who was the treating surgeon, and who originally provided reports in the plaintiff's case. Professor Norman has a most impressive curriculum vitae, including being the author with Professor Sir Paul Brambly of the leading textbook on jaw joints.

37. Professor Norman said in his evidence-in-chief (T 158) -

... it is not in my mind possible for dental forceps applied to an upper tooth to move the coronoid process which is quite closely allied to the forceps at the time of extraction, it is not possible to move the coronoid process sufficiently to damage the ipsilateral joint, that is the joint on the side. It is theoretically possible that the joint on the contralateral side could suffer some mild closed injury, but it wouldn't be sufficient to give rise to subsequent bony ankylosis.

38. He said that only major trauma could cause such an injury, not the type of trauma associated with the removal of a tooth.

39. In cross-examination Professor Norman amplified this point by saying that when removing an upper molar tooth (T168) -

It is not possible to displace the mandible. The biomechanics just don't work that way. It's not possible to move the jaw to the left by that amount and damage the disc on the left side.

40. When it was put to him that others had opined that it was possible to damage the disc by forcible extraction, he said (T 168) -

Huge force on the lower teeth applied with dental forceps applied to a tooth in the lower jaw, may certainly do some damage. But this case ... does not concern the extraction with forceps of a lower tooth, it is related to an upper tooth and the upper jaw is attached to the skull and it is immobile.

41. Dr Vickers, in his oral evidence, broadly supported Professor Norman's views as to the improbability of pressure to the upper jaw creating the damage sustained by the plaintiff to her jaw joint. He reinforced Professor Norman's evidence that "the upper jaw is anatomically disassociated from the hinge joint of the lower jaw" (T 140). He said in cross-examination in response to the proposal that the jaw damage was due to the trauma of extraction that (T 142) -

... I could certainly accept your proposal that if it was a lower wisdom tooth, but there is no connection between the upper jaw and the removal of wisdom tooth as such and the tempero mandibular joint. I think that to suggest that the practitioner pushed on the coronoid process of the jawbone, I mean in my clinical experience, I think that it is a very remote - it's a tenuous suggestion.

42. At the end of the defendant's case counsel for the plaintiff sought to recall Dr Egan to give evidence by way of a demonstration which was said would refute the evidence of Professor Norman and Dr Vickers that it was not possible to cause damage to the joint by applying force in extracting an upper molar. I refused leave to recall Dr Egan, because this issue had clearly been raised in the expert reports that had been served before the hearing, and Dr Egan had not previously expressed an opinion on this, and indeed had made the point that he was not himself qualified to give an opinion in relation to the extraction of teeth as this was not a procedure that he performed. Dr Egan had said in his oral evidence that he believed that the extraction was the cause of the jaw damage, and it seemed to me that it would be quite inappropriate to give him leave to give additional evidence at the close of the defendant's case.

43. In his oral evidence Dr Vickers directly addressed the temporal connection between the emergence of the plaintiff's problems and the extraction which, it seems to me, was the basis of the plaintiff's case. Indeed, it is clear from the letters Dr Egan sent to Professor Norman and Dr Peppitt that it was this temporal connection that convinced him that the extraction was the cause of the problem, and he was seeking expert support to explain the aetiology of the condition and the link to the extraction. Dr Vickers said (T 140) -

... there is evidence of joint breakdown and I think the fact that Mrs Hyland, you know, obviously underwent maybe a difficult extraction, it may well be a difficult extraction, but I think to say that it was the extraction that was the cause of the joint breakdown, I cannot see in the literature a direct connection between removal of an upper tooth and the joint breakdown that Mrs Hyland has in her tempero mandibular joint. I believe that she may well have had symptoms of some type of sub-clinical evidence or that maybe some type of disc displacement or...wear and tear of her jaw joint and I think that unfortunately, she had a difficult extraction. I think the two - the procedure or the problems were coincidence rather than a direct cause and effect.

44. This evidence from Dr Vickers, who was the plaintiff's first treating specialist, is, it seems to me, of real significance, as the strongest case in support of her claim seems to stress the fact that her problems emerged the day of or the day after the extraction as establishing a cause and effect relationship, in the face of quite strong evidence that pressure applied in removing an upper molar could not damage the joint.

45. On all the evidence I am not satisfied on the balance of probabilities that the damage to the plaintiff's jaw was caused by excessive force at the time of the extraction of the tooth. It follows that, even though I am satisfied that the defendant should have ensured that an x-ray of the root of the tooth was taken before the extraction, this negligence was not the cause of her present difficulties.

46. If trauma at the time of extraction is not made out as the cause of her problems, as I have found, an alternative basis for the negligence claim remains the theory advanced by Professor Norman, that the ankylosis of the joint was caused by an infection which was, in his view, more probably than not caused by a shower of bacteria released when the decayed tooth was removed. Although pleaded in the plaintiff's case, this version was not strongly advanced, and indeed much of the time of the trial was taken up by witnesses in the plaintiff's case seeking to detract from this theory.

47. It was common ground that infection could be a cause of damage to the cartilage in the jaw joint, but Dr Peppitt said that this was no longer a common finding in the developed world.

48. Professor Norman was of the view that the bacteria released by the extraction of a decayed tooth could set up an infection which could attack the cartilage in the jaw joint leading to the damage sustained by the plaintiff, and that this could occur within 24 hours. It is significant that this is consistent with the emergence of the plaintiff's difficulty with opening her jaw, which she said emerged when she tried to eat a cheeseburger the day after the extraction. Professor Norman also said that any such infection would have been cleared up by the powerful antibiotic that Dr Langtry prescribed five days after the procedure.

49. There was considerable debate as to whether the plaintiff was displaying clear signs of a febrile illness at the time of her consultation with Dr Langtry, with the proposition being put in the plaintiff's case that she was not feverish.

50. Professor Norman claimed that the appearance of the joint damage was consistent with infective damage, but Dr Peppitt, who operated with him, gave evidence to the contrary in the plaintiff's case. Professor Norman also relied on the pathology report of Dr F Bonar who said, in examining the joint tissue following his operation, that -

there is no evidence of an active inflammatory synovitis although an old burnt out inflammatory synovitis cannot be excluded".

51. Although she felt that this was consistent with infection as the cause of the problem, the plaintiff called Dr Bonar and lead from her the opinion that the chances of the tissue damage being caused by infection were, where one is a possibility and ten is certainty, between one and three (T 193).

52. Despite this evidence being lead in the plaintiff's case against the theory that the jaw damage was caused originally by bacterial infection, Mr Crowe submitted for the defendant that on all of the theories as to the original cause, bacterial infection was the most likely, and given Professor Norman's eminence in the field of jaw disorders, on all of the evidence I am satisfied, on the balance of probabilities, that the original cause of the jaw disorder was a bacterial infection flowing from the breaking up of what Dr Huen described as a very decayed tooth. Professor Norman described the extraction and breaking up of a decayed tooth as creating a "shower of bacteria" which could set up an infection which within 24 to 36 hours could cause the damage which he observed on operation to the plaintiff's jaw, and I am satisfied that this is the most probable cause of her infection.

53. Having established this to be the most likely outcome, the question remains whether the defendant was in breach of his duty of care in failing to warn the plaintiff of the risk of infection, and whether the failure to warn caused the problem. Mr Crowe conceded, properly, that if Professor Norman's evidence is accepted, which he said it should be, it would follow that failure to warn would be made out. I would add that the need for a warning of infection must be greater in a case such as this, where Dr Huen described the tooth as very decayed, and where he did not have an x-ray of the root of the tooth. The real issue in this case was that of causation.

54. Mr Crowe said that a Court should be wary of a plaintiff who, after the event when a potential medical misadventure has occurred, says that they would not, if warned, have undertaken the procedure. So much follows from Rosenberg v Percival [2001] HCA 18, (2001) 205 CLR 434. Although the plaintiff said that she had a busy day with other appointments arranged, and would, if properly warned, have elected to defer the extraction at least until her usual dentist was available, I am inclined to the view that, on balance, the plaintiff would in any event have heeded the advice of Dr Huen that a badly decayed tooth had to be removed. However, that is not the end of the matter, as the plaintiff will make out her case here not just if she satisfies the Court that she would have deferred the procedure, but if she satisfies the Court that, if advised of the risk of infection from a badly decayed tooth, she would have obtained antibiotic cover.

55. The plaintiff is a nurse, and she has a general knowledge of such matters. She also said that with a previous extraction of a wisdom tooth she had been given antibiotics. Her brother is a general practitioner and it is entirely plausible and reasonable that she says that, if warned that the badly decayed tooth on extraction and break up could cause an infection, she would have proceeded to obtain immediate antibiotic cover either from Dr Huen or from her brother. Professor Norman said, and this evidence is uncontradicted, that an antibiotic such as Augmentin that was prescribed later by Dr Langtry would have attacked and defeated the infection before it did the damage, which he says probably occurred within 24 hours, consistent with her history of the onset of the symptom of difficulty of opening her jaw.

56. The test for causation where there has been a failure to warn a patient about a risk was set out in Rosenberg v Percival by McHugh J at [24] as follows:

Under the Australian common law, in determining whether a patient would have undertaken surgery, if warned of a risk of harm involved in that surgery, a court asks whether this patient would have undertaken the surgery. The test is a subjective test. It is not decisive that a reasonable person would or would not have undertaken the surgery. What a reasonable person would or would not have done in the patient's circumstances will almost always be the most important factor in determining whether the court will accept or reject the patient's evidence as to the course that the patient would have taken. But what a reasonable person would have done is not conclusive.

57. Mr Stretton, for the plaintiff, made the submission that, not only would a reasonable person, if warned that there was a real risk that could be averted by obtaining antibiotics, obtain such protection, but that the plaintiff, being a nurse and a person who had previously been advised to take antibiotics for a wisdom tooth extraction, and having a brother who was a general practitioner, should be believed when she says that, if properly advised, she would have obtained antibiotic cover. I am satisfied that this is so, and that if she had obtained such cover, she would not have experienced the ongoing problems that she has suffered. Accordingly, I find that her difficulties have been caused by the negligent failure of the defendant to warn her of the risk of infection and the availability of antibiotics to prevent infection.

58. It was argued that because she was a nurse and because she was generally aware of the use of antibiotics, and had previously been advised to take antibiotics following the removal of a tooth, the failure to warn was not the cause of her failure to take antibiotics. It seems to me that this is not sustainable. A patient is not expected to self-diagnose the need for antibiotics, and indeed medical practitioners would properly be criticised if they were to prescribe such substances on a patient's self-diagnosis, even where that patient is a trained nurse.

Damages

59. This was not a case where there was significant dispute between counsel on the issue of damages. The plaintiff was clearly accepted as a witness of truth in regard to her description of the impact of the ongoing jaw difficulties on her life, and her employment, and properly so.

60. Before this condition the plaintiff had no difficulties with her jaw. The ankylosis was a painful and disabling condition, and in order to treat the condition she has had to wear, and continues to have to use, a jaw splint, which is both inconvenient and unsightly. She has had to undergo, and will continue to have to undergo, painful manipulation from time to time to maximise her jaw movement, and she has had to undergo, and will undergo in the future, surgical intervention. Counsel were in agreement that general damages should be significant, and I am in agreement. I would award $90,000 for general damages, with $40,000 for the past, leading to interest of $11,270 for a total award of $101,270.

61. Counsel agreed that past out-of-pocket expenses should be awarded if liability were found in the sum of $15,783.95. She will need ongoing appointments to adjust and from time to time replace her splint, and Professor Norman is of the view that she will need a further operation. Counsel acknowledged that the sum for future out-of-pocket expenses was difficult to quantify, but it seems to me that a global award of $12,000 would be appropriate in this case.

62. The plaintiff's economic loss claim was agreed by counsel to be in the sum of $10,000, the bulk of which will be an adjustment for sick leave, so that she has in fact only been out of pocket for the sum of about $1000, which was agreed to be the sum for which interest should be allowed, amounting to interest of $155 for a total award of $10, 155.

63. This amounts to an award of $139,208.95, made up as follows:

General damages: $90,000.00

Interest: $11,270.00

Past out-of-pocket expenses: $15,783.95

Future out-of-pocket expenses: $12,000.00

Past economic loss: $10,000.00

Interest: $ 155.00

64. I award the plaintiff the sum of $139,208.95, which I consider to be appropriate in all the circumstances of the case, with costs.

I certify that the preceding sixty-four (64) numbered paragraphs are a true copy of the Reasons for Judgment herein of his Honour, Justice Connolly.

Associate:

Date: 3 September 2003

Counsel for the plaintiff: Mr G Stretton

Solicitor for the plaintiff: Stacks with Snedden Hall & Gallop

Counsel for the defendant: Mr R Crowe SC

Solicitor for the defendant: Abbott Tout

Dates of hearing: 30 June 2003, 1-2 July 2003

Date of judgment: 3 September 2003