Ever since the safety of amalgam became a public controversy in the 1990s, a good number of Dr Barnes’s patients had raised concerns about the amalgam restorations that he had put in their teeth. They feared that mercury from the restorations might precipitate any number of immunologic disturbances, including multiple sclerosis. Dr Barnes had read as much as he could about this controversy and had concluded that the American Dental Association (ADA) was correct: There was no objective evidence to substantiate these concerns. On the other hand, he personally felt that there might well be a reasonable basis for concern and that there was insufficient evidence to absolutely rule out the possibility that the mercury was a problem.

Dr Barnes was not happy about the prospect of removing the amalgam restorations that he had placed over the years. Amalgam had been in use for more than 100 years and was being improved upon all the time. Furthermore, he felt that the alternative materials, despite significant improvements, were often still less satisfactory than amalgam. He decided to take the position recommended by the ADA. He would remove the amalgam restorations if requested by his patients, but only after a thorough discussion about the problems of the alternatives. He also decided that if a patient raised no concerns, he would not discuss the issue at all. However, the latter decision bothered him. He felt that the absence of definitive evidence of harm did not necessarily certify that the amalgam restorations were completely harmless, either. Dr Barnes began to wonder if he should inform his “quiet” patients about his concerns.

DISCUSSION:

One of the elements of informed consent is an explanation of the treatment options. Thus, Dr Barnes must decide whether to present the alternatives to the use of amalgam. To resolve his dilemma, Dr Barnes can decide whether to follow the professional standard or the reasonable person standard. If he uses the professional standard, it is clear that he could follow the path recommended by the ADA and taken by the great majority of his colleagues.

If he uses the reasonable person standard, it is not as clear what he should do. The question is whether a reasonable person would need to know that: (1) there has been recent widespread public discussion about the safety of amalgam restorations, (2) the ADA has responded by reaffirming amalgam’s safety, and (3) while Dr Barnes basically agrees with the profession, he is not totally satisfied that all of the evidence is yet available. Should Dr Barnes discuss the amalgam controversy with his patients, even if they do not mention it? If he relies on the professional standard, he will need to explain only the treatment options that were mentioned by his colleagues. If, however, he adopts the now-preferred reasonable person standard, he will need to determine whether reasonable patients would want the additional information about the treatment options and to provide it if they do.

Mrs Dorothy Wolfe was 40 years old, lived in a wealthy suburb of a large midwestern city, and knew that she needed periodontal care. Because she was insured by a major insurance company, she checked her roster of participating periodontists and selected Dr Margaret Wozniack from a list of three.

On her first visit, Dr Wozniack explained that Mrs Wolfe needed extensive scaling and curettage. This would be accomplished in two more visits. The cost would be $75 for the diagnostic visit and $450 for each of the other two visits, for a total of $975. After each visit, Mrs Wolfe paid $225; her insurance would cover the rest.

The treatment went well. However, Mrs Wolfe never saw Dr Wozniack after the initial consultation; the entire treatment was done by the hygienist. This bothered Mrs Wolfe, but she was unsure about the standards of treatment and never complained.

While paying after the last visit, the receptionist said that Dr Wozniack wanted to see Mrs Wolfe in a month for a follow-up visit. Mrs Wolfe agreed. On her return she was pleased that Dr Wozniack actually examined her, checking both her periodontium and her occlusion. As Mrs Wolfe was leaving, the receptionist informed her that she owed $125 for the visit. Mrs Wolfe angrily refused to pay, saying that it was not part of the original treatment plan. She discussed her complaint with the peer review committee of the dental society. The committee chair then called Dr Wozniack to try to arrive at an equitable settlement.

DISCUSSION:

This case raises issues involving the first three elements of an informed consent. Consider first the treatment alternatives. The treatments involved in this case are not terribly unusual. Dr Wozniack may even consider this to be a case where no consent is required. In fact, she did give Mrs Wolfe some information about her proposed treatment plan. She told her she wanted to do scaling and curettage and that it could be accomplished in two visits. She also quoted her a $975 fee. Should Dr Wozniack approach this interaction as one in which she is telling her patient what she is going to do, or as one in which she is proposing a treatment plan to which the patient may or may not consent?

The answer will depend, in part, on whether she perceives the situation as one in which there are alternatives. Are there any alternatives in this case? Could the treatment have been done in a different number of visits? Could additional procedures be done or some omitted? Could Mrs Wolfe have simply decided against the entire plan? Were there significant variations in the technique that would have involved different risks, benefits, discomfort, or costs? Keeping in mind that one possible option for Mrs Wolfe would be to decline all treatment, an argument can be made that the assumption of only one possible course of action is probably unreasonable. If so, Dr Wozniack could propose what she thinks is the best course and attempt to obtain Mrs Wolfe’s consent.

There is another option, which Donald Sadowsky calls “multiple prescription dentistry.”¹² Dentists can present a number of treatment plans that are within the range of plausibility, each of which might make sense for some patients but not others. The approach is built on the assumption that there is no single, definitive treatment plan that is objectively the best for patients. It might also be used when a dentist recognizes that, even if there is a single “best” course, that course may not be rational for a patient given his or her economic, social, and psychological situation.

Under multiple prescription dentistry, the concept of informed consent as practiced by many dentists does not really apply. To these individuals, informed consent implies that the dentist will first make a choice and then ask the patient to approve it. With the multiple prescription concept, however, if the dentist realizes that there are several possible options or suboptions within reason, he or she may feel compelled to refrain from presuming to know which is best for a particular patient.

Under the professional standard, Dr Wozniack would need to determine what her colleagues would have told Mrs Wolfe. She would need to decide whether they would have mentioned the cost, the follow-up visit, the fact that the hygienist would perform all of the treatment proposed, and any variations in what could be done for Mrs Wolfe. Under the reasonable person standard, Dr Wozniack would have to determine what a reasonable person in Mrs Wolfe’s situation would want to know about each of these items.

This case also introduces a second element of informed consent: an explanation of who will perform the procedures. When Mrs Wolfe agreed to the proposed treatment plan, she apparently assumed that Dr Wozniack would perform the procedures and may well have based her judgment about the reasonableness of the cost on that assumption. If someone other than the dentist will perform any of the procedures, the patient has a right to understand that fact. Sometimes it may be obvious, as when a hygienist provides routine scaling and cleaning, but in other cases a patient would have no basis for knowing. An informed consent must include adequate understanding of who will perform all aspects of the care.

Finally, the case introduces a third element of an adequately informed consent: accurate information about the charges. It seems clear that if Dr Wozniack planned to include a follow-up examination in the treatment plan, it should have been disclosed to Mrs Wolfe as part of the overall proposal with the cost included so that she could agree to the total anticipated fee. Only those elements that legitimately could not be anticipated in advance should be added to the treatment plan at a later time. If Dr Wozniack intentionally left out the follow-up visit in order to make the cost seem lower than what was actually expected, consent was surely inadequate.

Tammy Williams, an 8-year-old patient of Dr Bob Zarnecki, was referred to Dr Joe Corbin, a pediatric dentist, for removal of an abscessed mandibular primary molar. Tammy had become very upset when Dr Zarnecki had attempted local anesthesia. At first he referred her to an oral surgeon for extraction under general anesthesia. However, Tammy’s mother, Mrs Williams, refused because her sister had almost died while having extractions under general anesthesia. Dr Zarnecki then referred Tammy to Dr Corbin for the extraction with nitrous oxide conscious sedation, no other treatment being necessary.

Dr Corbin’s examination confirmed the presence of a draining abscess. He explained the risks of nitrous oxide and how it differed from general anesthesia. Mrs Williams was still apprehensive and authorized its use only if absolutely necessary.

On the day of the procedure, nitrous oxide was, in fact, necessary. However, the extraction occurred without significant incident. During the treatment Dr Corbin noted that the first permanent molars were deeply grooved and somewhat hypoplastic. They needed sealants. Dr Corbin knew that Dr Zarnecki did not use sealants because he did not think that they worked.

Dr Corbin wondered whether he should tell Mrs Williams that he thought that sealants were highly indicated for Tammy. He knew that if he did, he would most likely offend Dr Zarnecki. Dr Corbin decided to state his views. He explained that sealants have been proven to prevent decay but that not all dentists used them. However, because Tammy was quite fearful of injections, he advised that she have the sealants applied.

DISCUSSION:

Here two different consent issues could be singled out for special attention. First, Dr Corbin needs to determine what information to transmit in regard to treatment alternatives—what he should say about local anesthesia, nitrous oxide, and general anesthesia options. There may be risks that Dr Corbin’s colleagues generally do not discuss with patients but that reasonable patients would nevertheless wish to know about. There may be other treatment options or variations on these options that might be disclosed under any of the three standards. It is clear that the risks of general anesthesia and nitrous oxide need to be discussed, but, given Mrs Williams’ level of concern, Dr Corbin probably should discuss the use of local anesthesia as well. Local anesthesia for dental procedures is familiar to most people and its successful use is so widespread that it is generally considered safe by the public. Yet, as with any agent, it can cause problems that include toxic effects, allergic reactions, and even death. On the other hand, the toxic effects only occur when local anesthesia is used in excessive quantities; the frequency of any kind of allergic effect is less than 0.0001% and the frequency of death is approximately one death per trillion injections.

How can dentists decide upon the minimal criteria for the discussion of risks? The answer, as suggested by Hirsch and Gert,⁹ lies in a combination of the frequency and intensity of the problem. Judgments are made starting with the idea that problems that are rare and inconsequential need not be disclosed. Somewhere on an ascending scale, a possible outcome will be sufficiently frequent and serious that reasonable people need to know about it. In the case of local anesthesia, it is generally agreed that patients who have not had it before should be told that their soft tissues will feel numb for a couple of hours. At the same time, most dentists feel that because the frequency of serious side effects is very rare, specific discussions of the risks are not necessary. Thus, relying on the professional standard, Dr Corbin probably does not need to disclose them. However, it is still an open question whether the typical patient would want to know about them. Even rare side effects may need to be discussed, especially if the effect is very serious, such as death. A dentist might conclude that a risk of one per trillion is so remote that reasonable patients would not find the information relevant to their decision to consent. Still, Mrs Williams’s unusual concern may require disclosure based on the subjective standard.

The second consent issue concerns the sealants. Under the professional standard, the appropriate question is whether other pediatric dentists receiving such referrals would raise the sealant option. Knowing that the referring dentist does not use sealants might dissuade dentists from raising the issue. However, the problem here is that the usual practice does not seem to be the appropriate basis for deciding whether to bring up the sealant topic with Mrs Williams.

Under a reasonable person standard the key question is whether it is likely that a typical reasonable patient (or in this case, reasonable parent) would want to know about the sealants. If so, what would she want to know? It seems quite likely that Mrs Williams would want to know Dr Corbin’s opinion that they are “highly indicated.” She probably would also want to know that the family’s primary dentist disagrees. If Dr Corbin decides that Mrs Williams would want to know about the sealant option, bringing it up could involve an apparent conflict with the ADA’s Principles of Ethics and Code of Professional Conduct, which states that only the treatment that is requested by the referring dentist should be performed on referred patients. Because the ADA Code also commits the dentist to working for the patient’s welfare, this may be a case in which Dr Corbin must violate one or the other of the Code’s provisions. If Dr Corbin thinks the sealants are in Tammy’s interest and that Mrs Williams would want to know about the option, he seems duty-bound to bring the subject up.

The University of Washington collaborated with the University of Lisbon in Portugal to do a study funded by the National Institute for Dental and Craniofacial Research (NIDCR). The topic of the study was the safety of dental amalgam, a longstanding problem that still had no definitive resolution. Although government panels still recommended the use of amalgam in the absence of good evidence of harmful health effects, they also pointed out that more research on health effects was necessary.

The study was to involve 500 children, ages 8 to 10, in the Casa Pia school system in Lisbon. Eligible children would have dental caries and no previous exposure to amalgam. The children would be randomly assigned to two groups, one of which would receive amalgam for the restoration of large posterior lesions, with alternative materials (mainly composites) used elsewhere. The other group would receive alternative materials for all lesions. Each year, all of the participants would undergo a number of neurobehavioral and neurological tests as well as urinary mercury analyses.

The study was ready to begin when an ethicist on the Data Safety and Monitoring Board expressed concern about the consent process. About 20 percent of the Casa Pia students were wards of the state, either because of their status as orphans or because of unstable family situations. For these students, the director of the Casa Pia school system was authorized to give consent—one person for about 170 children!

At first, the investigators considered finding an alternative way to obtain consent for the 20 percent in question. However, the director was a highly respected member of the Lisbon community and to risk insulting his ability to meet this responsibility adequately might have been damaging, both to the director and to the study. Furthermore, the director previously had, in fact, been designated as the children’s legal guardian.

The investigators saw this as an important issue because they felt it dealt with the balance between expecting benefits in research on the one hand and the need to protect a potentially vulnerable population on the other.

DISCUSSION:

This case poses several important consent issues. The first is determining which elements of this intervention are research and how to explain that to the parties responsible for the consent. One may view the use of amalgam materials as a current standard practice, so the mere fact that the children in the experimental group would receive amalgam does not constitute research. Alternatively, if the concerns about amalgam were so great that they were no longer classified as standard practice, then they would have to be described as research interventions. Of course, even if the amalgam restorations were considered standard practice, the treatments would still require consent just like any other therapy and the controversy over the risks of amalgam would have to be presented. Determining how to obtain that consent is, as we shall see below, rather complicated in this case. Likewise, the same issue arises with respect to the use of composites, which, like the use of amalgam, also constitutes a standard practice and therefore does not have to be presented as research.

At least two features of these interventions appear to be research—that is, undertaken for the purpose of producing generalizable knowledge. The randomization of children to receive amalgam or composite for their posterior lesions is the first. The subjects and their surrogate, the director of the Casa Pia school system, need to know that they are being assigned at random to a treatment group. This is something that would never be done in routine therapy; it potentially undercuts the clinician’s judgment about which of the two materials is preferred in individual cases.

Presenting the risks of these two options is also complex. If amalgam had been questioned (which is the premise that led to the study), then its suspected risks must be presented, but any potential risks of the composite must be presented as well. Labeling any of these risks as “research risks” will depend on whether one considers one or the other treatment a deviation from standard practice.

The second major intervention that is research and must be identified as such is the neurobehavioral and neurological tests and urinary mercury analyses that will occur once the restorations have been placed. Both the students and their surrogate need to know that these procedures are not required for regular therapy.

Even if the investigators can properly identify those interventions that constitute research, they still need to determine whether they have an adequate consent process. Since this study is taking place in Portugal, it must meet all Portuguese requirements. But because the research is being conducted by the University of Washington and is funded by the NIDCR, it must also meet American standards, including approval by the University of Washington institutional review board, which governs all of its research, and by the NIDCR.

The subjects of this study are children between 8 and 10 years of age. They cannot themselves give an adequately informed consent, but they can be expected to give their assent and should be excluded from the study if they refuse. The concepts of consent and assent from minors is discussed in Case 36.

In addition to meeting Portuguese and American standards for consent or assent from the children, adequate consent must also be obtained from the children’s parents or surrogate. That is what led to the controversy over the involvement of the director of the Casa Pia school system. As the legal guardian for a portion of the children, he would be the one to give the consent if anyone could. Because the study involves research procedures on patients who cannot themselves give consent and because it involves some potential risks (including the risk of exposure to mercury from the amalgam when other treatment options were available), there is controversy over whether parents or guardians can give consent or permission for their children to enter the study, The American norm is that parents can give permission provided that the risk is related to treatment for a condition from which the children suffer and is only a minor increment above the risks of ordinary life. Because the children have caries lesions and the risk of the amalgam is, at most, minor, the study seems to meet this standard; the parents could give permission if they wanted to.

The problem is more complex for the children in the Casa Pia school system who belong to a particularly vulnerable group—orphans or children otherwise separated from their families. Relying on a surrogate, even a legal guardian, to approve the children’s entry into a research project is controversial. Some hold that it is only permissible if the study could not be done on children from intact families. Others hold that it can include vulnerable subjects, provided that other children from intact families are included as well. The safest course would have been to exclude those Casa Pia children who were wards of the state and any others who do not have parental involvement in the consent process.