Reduction of healthy teeth in nonhuman primates

I would like to thank the authors of the recent report¹ describing a capuchin monkey with multiple canine tooth root abscesses following crown reduction of the canine teeth. The report aptly demonstrates one of the reasons why the AVMA opposes the reduction of healthy teeth in nonhuman primates and carnivores.² However, I believe there may be a better take-home lesson than the one suggested by the authors. An owner's request for tooth reduction or removal to prevent injuries from aggression can, I believe, be interpreted as tacit acknowledgement that the owner is unable to handle the animal safely. Owners who wish to keep dangerous animals are ethically responsible for learning safe handling methods. Thus, veterinarians faced with these types of requests should instead refer owners to a certified behaviorist familiar with techniques for handling aggressive animals. If behavioral modification cannot ensure safe handling, a technique called “protected contact” that is used by zoos to ensure the safe handling of dangerous animals should be considered as an alternative.

Note that these principles apply to all dangerous animals, including domestic animals. The authors incorrectly state that the AVMA policy applies to “removal or reduction of healthy teeth in captive nonhuman primates or exotic and wild (indigenous) carnivores.” In fact, the policy applies to all carnivores, including domestic dogs and cats.³

V. Wensley Koch, dvm

Loveland, Colo

The authors respond:

On behalf of the authors, I want to thank Dr. Koch for her thought-provoking comments regarding our recent publication. Dr. Koch brings up an excellent point that pet owners who request canine tooth reduction or removal in nonhuman primates and carnivores are likely unable to handle those animals safely. I wholeheartedly agree. Requests for these procedures certainly make me concerned about the ability of a pet owner to understand the behavioral and welfare needs of the animal. I agree that working with a certified behaviorist would be preferred in these circumstances, when available.

In this particular case, the pet monkey was brought to The University of Georgia Veterinary Teaching Hospital after already having had its canine teeth reduced several months previously. We witnessed one of the unfortunate complications (tooth root abscesses) associated with canine tooth reduction without appropriate endodontic repair. Our impetus for submitting this manuscript was to emphasize that, in addition to the welfare concerns surrounding this practice, there are serious medical complications that veterinarians should be aware of. We strongly recommend that canine tooth reduction be performed by an experienced veterinary dentist and only when medically necessary or for approved scientific research. Please note that the University of Georgia Veterinary Teaching Hospital will not perform this procedure, because it is considered a mutilation surgery by the Royal College of Veterinary Surgeons. Their policy¹ is as follows:

“Monkeys: This procedure is only acceptable if carried out by a veterinary surgeon in order to protect the animal itself—for example, if it is prone to damage itself badly by self-mutilation or if it has a tooth or jaw infection. Teeth cutting/removal should not be carried out in order to protect the owner or his property. Under such circumstances the proper course of action is either to house the animal properly or to transfer it to other premises.”

Holly Burchfield, dvm

Atlanta, Ga

Questions study of acupuncture for dogs with hip dysplasia

Teixeira et al,¹ in their recent study on dogs with hip dysplasia treated with acupuncture, carprofen, or a placebo, reported that “acupuncture and carprofen both decreased lameness in dogs with HD, but only acupuncture alleviated HD-related pain” and concluded that “acupuncture performed with the protocol and acupoints used in this study appears to be a viable option for improving quality of life in dogs with HD.” Their results, however, do not support this conclusion, and the outcome measures the authors evaluated did not show any clinical benefit of acupuncture compared with a placebo.

The study incorporated three subjective outcome measures (Helsinki Chronic Pain Index, Canine Brief Pain Inventory, and visual analogue scales for pain and degree of lameness) and one objective measure (kinetic force plate analysis). These were compared within and across treatments at multiple times before, during, and after treatment, resulting in a large number of comparisons.

According to the authors, “there was no difference in the HCPI, CBPI, and VAS data among the 3 treatments at any time point” and “kinetic evaluation findings did not differ among the groups.” All groups showed variations and improvement. Overall, however, those treated with acupuncture did no better than the other groups, including the placebo group.

A few post hoc comparisons were reported showing statistical differences between the acupuncture group and the placebo or carprofen group, but these were the exceptions, and most such potential comparisons failed to show any difference. This sort of selective use of statistical testing to create an impression of effect when the bulk of the data show no effect is misleading and illustrates a widespread practice the American Statistical Association has formally condemned: “Cherry-picking promising findings, also known by such terms as data dredging, significance chasing, significance questing, selective inference, and ‘p-hacking,’ leads to a spurious excess of statistically significant results in the published literature and should be vigorously avoided. … Whenever a researcher chooses what to present based on statistical results, valid interpretation of those results is severely compromised.”²

The authors used carprofen as a positive control in their study. There is robust evidence that carprofen and other NSAIDs are effective analgesics in dogs with osteoarthritis.^3,4 It is surprising, therefore, that carprofen had no apparent effect beyond placebo, and this calls into question the accuracy of the outcome measures used by Teixeira et al.

Given the apparent lack of efficacy of the positive control and the failure to identify meaningful differences between treatment groups in nearly all outcome measures, the most appropriate conclusion is that this study does not provide evidence to support the use of acupuncture for dogs with hip dysplasia. The data are far more compatible with the hypothesis of no difference between treatment and placebo, and the improvement seen in all groups was likely the result of nonspecific clinical trial effects (eg, the Hawthorne effect⁵) and natural variation over time.

Negative research findings are just as important and useful as data that do show efficacy. This study is a valuable contribution to our understanding of the potential role of acupuncture in the treatment of hip dysplasia. But it is misleading to characterize the results as supporting the use of this acupuncture protocol to treat pain or lameness associated with this disorder.

Brennen McKenzie, ma, msc, vmd

Adobe Animal Hospital

Los Altos, Calif

The author responds:

Dr. McKenzie is correct that in our study¹ of dogs with hip dysplasia treated with acupuncture, carprofen, or a placebo, results for our subjective (Helsinki Chronic Pain Index, Canine Brief Pain Inventory, and visual analogue scales for pain and degree of lameness) and objective (kinetic variables obtained with a pressure platform) outcome measures did not differ among groups at any time point. In addition, results of kinetic evaluations did not differ over time in any of the groups.

Nevertheless, we did detect some differences among groups. For instance, the percentage of dogs with at least a 30% improvement in CBPI score, compared with baseline score, was significantly (P = 0.034) higher for dogs treated with acupuncture (13/15) than for dogs treated with a placebo (7/16), although not significantly (P = 0.446) different from the percentage for dogs treated with carprofen (11/16). Only 2 dogs required rescue analgesia, and both were in the carprofen group. In addition, only dogs in the acupuncture treatment group were found to have significant improvements in CBPI scores (total score and pain severity and pain interference subscores) and the VAS score for pain at various times, compared with baseline scores, and only dogs in the acupuncture and carprofen groups had improvements in the VAS score for locomotion. Therefore, we do not agree that the statistical testing created “an impression of effect,” as suggested by Dr. McKenzie.

We are aware that carprofen and other NSAIDs have been reported to be effective analgesics in dogs with osteoarthritis, and we do not have an explanation for why dogs in the carprofen group in our study did not perform better than dogs in the placebo group. However, in one of the reviews supporting the efficacy of NSAIDs in the treatment of osteoarthritis mentioned by Dr McKenzie, Innes et al² reported that none of the selected studies met all 3 of their criteria for inclusion of essential elements for evidence-based medicine. Therefore, the efficacy of NSAIDs should perhaps be questioned and we should possibly seek new strategies to treat osteoarthritis.

The authors have considerable experience in working with acupuncture and conventional medical approaches to treat dogs with chronic neurologic and musculoskeletal diseases, and our clinical impressions support the benefit of acupuncture. Therefore, we feel confident in our conclusion that acupuncture may be a viable option for improving the quality of life in dogs with hip dysplasia. However, we understand that conventional medicine, including NSAIDs, is very important as a multimodal approach to alleviate chronic pain and argue that we should use all possible therapeutic tools to treat our patients.

Stelio P. L. Luna, dvm, phd

Department of Veterinary Surgery and Anesthesiology

Faculty of Veterinary Medicine and Animal Science

São Paulo State University Botucatu, Brazil

Developing diversity in veterinary medicine

As the veterinary profession evolves in response to the myriad political, social, economic, and scientific changes it faces, it must become more diverse. We are long overdue.

We should be proud of many aspects of our profession. The fact that we are the whitest profession in America is not one of them, though, and we must become more representative of the communities we serve. Embracing diversity will create a profession in which differences are not only respected and appreciated but also leveraged as sources of creativity and advancement. The veterinary profession needs to become more innovative—professionally, economically, and socially—and diversity is vital to that effort. It brings multiple perspectives, a more heterogenous approach to problem solving, and greater social intelligence to solutions.

Unfortunately, the attitude that “we will admit all qualified applicants into veterinary training programs regardless of their background” has not broadened our demography. The fact that there are few diverse, qualified applicants may not reflect a lack of interest or experience. Instead, it may be the result of a lack of opportunity, lack of resources, lack of applicant confidence, or lack of inspiration and mentorship. All of us, as veterinarians, have the ability and responsibility to increase opportunity and inspire the next generation of colleagues.

It takes work and dedication to effect this change. We all encounter children in our professional world, often daily, and many are from diverse backgrounds. Simple, seemingly unimportant actions, such as sharing an opportunity to listen to a dog's heartbeat with a stethoscope, looking at ear mites or blood smears through a microscope, or explaining a radiograph with a child, can have an immense, lifelong impact. When was the last time you engaged a group of students from an underserved school in a discussion of the excitement and rewards associated with the veterinary profession? There are so many young potential veterinarians who have the intellectual capacity and the untapped interest to join our profession, but they aren't being recognized. Some may actually feel that they aren't welcome in the veterinary profession.

The time has come for all of us to step up and help move our profession forward. The current paradigm for broadening our palette isn't working, and it can't without active effort by all of us. There is no excuse for us to deny the importance of diversity within this amazing profession.

Michael J. Murray, dvm

Director of Veterinary Services

Monterey Bay Aquarium

Monterey, Calif