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Informed Consent Case Dismissed Against Dentist

By April 9, 2019June 27th, 2023Practice Management

On April 1, 2019, the BC Supreme Court released a decision wherein it dismissed a case against a dentist.  The case is Warlow v. Dr. Sadeghi, 2019 BCSC 463.  At issue in that case was whether the dentist had given informed consent to the patient and whether the dentist had been negligent in causing the patient harm.

Here are the facts: Dr. Ali Sadeghi performed oral surgery to remove an impacted wisdom tooth on Elaine Warlow.  During the surgery, Dr. Sasdeghi injured a nerve in Ms. Warlow’s lower right jaw, causing her permanent and debilitating nerve pain that altered “virtually every aspect of her life” (which all parties agreed was devastating to Ms. Warlow).

Ms. Warlow sued Dr. Sadeghi for negligence (a common ground to sue a dentist) but by the time it got to trial, the parties had agreed that Dr. Sadeghi had performed the wisdom tooth extraction to the standard of care required of him.

So the central issue before the court was whether Dr. Sadeghi had obtained informed consent before the surgery from Ms. Warlow.  She had signed a generic consent letter that included the following: “I am aware that in some situations there is a risk of temporary and/or permanent numbness or altered sensation of the lower lip, chin, gums or tongue.”

Now the BC Supreme Court found Dr. Sadeghi a credible witness (more so than Ms. Warlow).  And the Court specifically concluded that he had discussed alternatives to extracting the tooth, including the risks associated with those alternatives.  The Court also found that he did not tell Ms. Warlow that there was any risk of neuropathic or nerve “pain” and did not expressly identify that permanent nerve pain was a possibly consequence of the surgery.  While Dr. Sadeghi told her about the possibility of nerve damage, he described it as “pins and needles” and “tingling”, and that he did not tell her it could be permanent.

So was Dr. Sadeghi required to make that disclosure?

The BC Supreme Court found that Dr. Sadeghi ought to have included the word “pain” along with the other terms he used.  But was that it?  Case closed?  Had Dr. Sadeghi failed to obtain informed consent?


The Court went on to say that even though the language he used SHOULD have included the word “pain”, there’s a more stringent legal test that needs to be met in order for Dr. Sadeghi to be liable at law: Ms. Warlow must prove that (1) Dr. Sadeghi failed to adequately disclose risks that are foreseeable and (2) a reasonable person in Ms. Warlow’s circumstances would NOT have gone through with the treatment had the risks been adequately disclosed.

Was Risk of Injury Quantifiable?

The next question before the Court was whether Dr. Sadeghi failed to quantify the risks of injury to Ms. Warlow in terms of the possible nerve damage that could result from his treatment.  Dr. Sadeghi DID tell Ms. Warlow that the consequences of injury to her inferior alveolar nerve could be temporary or permanent and the quantified the risk at 1.5-2%.  He also said that the risk of permanent / severe neuropathic pain arising from IAN injury was so small because he had never heard of it.  There was evidence from other experts that corroborated that small risk.

So since there was NO evidence that Dr. Sadeghi knew or ought to have known and expressly quantified the risk of permanent and severe nerve pain arising from the specific tooth extraction (lower wisdom tooth, #48), the Court didn’t hold this against Dr. Saeghi.

Instead, they found that his description to Ms. Warlow that injury to the inferior alveolar nerve during surgery could be “temporary or permanent” was adequate in terms of disclosing the risk.

Would Ms. Warlow had still consented?

So Dr. Sadeghi didn’t use the words “pain” or “nerve pain” when he ought to have, but had discussed “temporary or permanent” nerve damage to her inferior alveolar nerve during the process of obtaining informed consent.

He shouldn’t have just used words like “pins and needles, numbness and altered sensation”.

So now we move onto the next part of the ‘informed consent’ test: had Dr. Sadeghi used the word “pain”, would a reasonable person in Ms. Warlow’s circumstances have still gone through with the procedure?

The Court held: “Yes”.

Why?  Well, the Court found that she had:

  • Ms. Warlow had previous sinus and dental treatments;
  • Just started a new career as a flight attended (her “dream job”)
  • Before the training program started, she experience an acute gum infection that was so painful she sought emergency help.
  • When Dr. Sadeghi explained to her the risks, benefits and alternatives to extracting her wisdom tooth, she would have understood all about the pain from her past experience
  • A reasonable person in her circumstances would have wanted to avoid having recurring infections while on the job
  • Ms. Warlow trusted and relied upon the advice of health professionals in the past
  • Ms. Warlow consented to the surgery knowing that there was a 1.5-2% risk of temporary or permanent nerve injury that could result in altered sensation, numbness and/or pins and needles.

For those reasons, the Court held that a reasonable person in Ms. Warlow’s shoes would have still gone through with the treatment even if adequate disclosure of the risks had been made.  As such, the case was dismissed against Dr. Sadeghi.

In Closing, the Court wrote:

84      As Ms. Warlow has not established the elements required to prove lack of informed consent, it follows that she cannot succeed in her negligence claim. In arriving at that conclusion I want to be very clear that Ms. Warlow did nothing wrong. She acted rationally and reasonably in response to her mouth pain by seeking out, obtaining, and relying upon the advice and assistance of appropriate professionals. There was no way that she — or Dr. Sadeghi — could have foreseen the consequences of the surgery. Ms. Warlow’s injury has been devastating. The fact that her claim has not succeeded means that, going forward, she will also likely have to cope with significant financial hardship. Although the law of negligence does not afford her a remedy, I say this to acknowledge the harsh reality of Ms. Warlow’s situation.

85      Ms. Warlow’s claim is dismissed. If the parties cannot agree on costs, they may apply to me to speak to them.


  1. Don’t Sugar Coat The Risks.  Use the Right Language, Even If It’s Not Part of Your Vocabulary.  Make It Part Of Your Vocabulary.
  2. Have Really Really Good Charting.  Extremely detailed because this will protect you in the future.
  3. Make Sure To Talk About Alternatives, Benefits, Risks.
  4. Continue To Do Research On Risks because this will help you disclose them / possibly quantify them.

P.S. if you’re curious about the current state of laws concerning obtaining INFORMED CONSENT, here’s the BC Supreme Court’s review of the jurisprudence:


39      Since 1980, the Supreme Court of Canada has affirmed that the law of informed consent protects the patient’s right to know and requires a high standard of disclosure: see Reibl v. Hughes, [1980] 2 S.C.R. 880; Hopp v. Lepp, [1980] 2 S.C.R. 192. In other words, the paternalistic approach, under which the professional was considered to be best placed to decide what treatment is in the patient’s best interest, has been rejected in favour of a patient-centred approach: Arndt v. Smith, [1997] 2 S.C.R. 539 at 553.

40      In Chen v. Ross, 2014 BCSC 374, aff’d 2015 BCCA 250, Justice Ballance explained what a health professional must disclose in order to ensure the patient has provided informed consent. She emphasized at paras. 303-304 that even remote risks that carry very serious consequences must be disclosed:

[303] Before obtaining a patient’s consent and implementing a course of treatment, the doctor must disclose to the patient the nature of the proposed treatment, its gravity, and any associated material, special and unusual risks that a reasonable person in the patient’s shoes would want to know: Reibl. In addition to informing the patient about the frequency or statistical chance of a material or special risk arising, the physician must also explain the nature and severity of the injury that could ensue: Brock v. Anderson, 2003 BCSC 1359.

[304] In the aftermath of Reibl, the courts have taken an expansive approach in characterizing risks that carry serious consequences as constituting material risks. In the result, the duty to disclose necessitates informing a patient of even a statistically remote risk where the potential consequences of it are sufficiently serious that a reasonable patient would likely consider it to be significant: Brito (Guardian ad litem of) v. Woolley, 2003 BCCA 397, leave to appeal to S.C.C. refused, [2003] S.C.C.A. No. 418, 2004 CarswellBC 880 (S.C.C.).

41      This does not include every conceivable risk. Risks that are not reasonably foreseeable need not be disclosed: Lewis N. Klar et al., Remedies in Tort (Toronto: Thomson Reuters, 2018) (loose-leaf updated 2018, release 6), vol. 2, c. 1, part III at para. 144. The fact that a risk subsequently materializes does not prove that it should have been disclosed. Equally, the fact that it is standard professional practice not to disclose a particular risk does not mean that disclosure is not required: Ediger (Guardian ad litem of) v. Johnston2009 BCSC 386 at paras. 148-155.

42      Inadequate disclosure is therefore the first element a plaintiff must establish on a negligence claim based on an alleged lack of informed consent. In addressing this element, the court must consider what risks had to be disclosed and whether they were adequately disclosed.

43      Even if the plaintiff establishes that a risk that was not disclosed (or not adequately disclosed) ought to have been disclosed, the plaintiff must prove a second element to establish lack of informed consent. He or she must also show that adequate disclosure would have made a difference — that is, knowing the undisclosed risk would have caused him or her to decline the proposed treatment. The courts have adopted a “modified objective test” to answer this question. The court must decide whether a reasonable person in the plaintiff’s shoes, “being the average prudent person who possesses the plaintiff’s reasonable beliefs, fears, desires and expectations,” would have withheld consent if the risks had been adequately disclosed: Arndt at 544; Chen at para. 307. This is a highly fact-based inquiry. Any questions the plaintiff asks during the informed consent discussion will be relevant, as will the plaintiff’s own testimony about how adequate disclosure would have affected his or her decision: Arndt at 550.

44      In summary, to establish a claim in negligence based on a lack of informed consent, a plaintiff must prove each of the following elements on a balance of probabilities:

a) A risk that should have been disclosed to the plaintiff was not disclosed or not adequately disclosed in advance of the procedure; and

b) A reasonable person in the plaintiff’s circumstances would not have consented to the procedure if properly advised of that risk.

The Content of this post is provided for informational purposes only. It is not intended to be legal, financial, tax, or other professional advice of any kind. You are advised to contact DMC (or other counsel) to seek specific legal advice concerning your individual situation.