EDITORIAL
Animal testing: a re-evaluation of what it means to
Endodontology
V. Nagendrababu
1
, P. E. Murray
2
, A. Kishen
3
, M. H. Nekoofar
4,5
, J. A. P. de Figueiredo
6
&
P. M. H. Dummer
5
1
Division of Clinical Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia;
2
Department of
Periodontics, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL, USA;
3
University of Toronto,
Toronto, Ontario, Canada;
4
Department of Endodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran,
Iran;
5
School of Dentistry, College of Biomedical and Life Sciences, Cardiff University, Cardiff, UK; and
6
Federal University of
Rio Grande do Sul, Porto Alegre, RGS, Brazil
Animal testing has a long history in the biological eval-
uation of medical devices used in Dentistry (ISO 7405).
Indeed, tests on animals have been used to develop new
interventions, materials, devices and drugs as they tend
to provide information on their biological mechanisms
of action, as well as their efficacy and side-effects before
human applications (Singh et al. 2016). As an exam-
ple, animal studies supported the basis for the under-
standing of orofacial development (Sharpe 1995).
However, animal tests are not essential and may be
prohibited by international and local laws, for example,
the European Union animal testing ban for cosmetics
(EU Regulation No 1223/2009) and the California Cru-
elty-Free Cosmetics Act (SB-1249). The animal testing
bans indicate a public policy shift away from animal
testing, to placing more reliance on the results from
lab-on chip, organ-on-chip, human cell-based studies
and clinical trials, to reduce the number of animals that
are sacrificed and protect patient or consumer health
and safety (Kimura et al. 2018).
It has been estimated that 115 million animals are
used for research testing worldwide each year, mostly in
the United States, Japan, China, Australia, France,
Canada, the United Kingdom, Germany and Brazil (Tay-
lor et al. 2008). Animal testing is not in decline, and in
many parts of the world it is on the increase or remains
at the same level as in the 1980s or 1990s (Taylor et al.
2008). The most common animals used in testing are
mice, rats, birds, sheep, guinea-pigs, monkeys, dogs,
cats, pigs, goats and cows. Up to 97% of dog and cat
owners regard their animals as a member of their family
(Risely-Curtiss et al. 2006). Moving forward, it cannot
be acceptable to publish tests done on dogs and cats,
because they are most often viewed as family members,
not laboratory animals.
Animal testing can be made more morally and ethi-
cally acceptable, by trusting animal welfare to the
extensive regulations governing animal tests. How-
ever, more protections to prevent animal pain and
suffering are mandatory, in addition to the safety net
of animal welfare regulations. Today, there can be no
ethical justification to publish articles where there
was a lack of pain monitoring, and where the pain
relief measures appeared to be inadequate, to prevent
avoidable animal suffering.
Poor quality animal studies tend to produce clini-
cally unreliable results (Pound & Bracken 2014,
Singh et al. 2016), which can defeat the purpose of
animal testing, rendering it useless. Steps to improve
the quality of animal research, the ARRIVE (Animal
Research: Reporting In Vivo Experiments) guidelines
(Kilkenny et al. 2010) and the SYRCLE (Systematic
Review Centre for Laboratory animal Experimenta-
tion) risk of bias tool (Hooijmans et al. 2014) were
developed to guide researchers. However, animal
studies in Endodontology often need exclusive infor-
mation related to the specialty. Hence, we are propos-
ing new guidelines named: ‘Preferred Reporting Items
for Animal Studies in Endodontology (PRIASE)’,
which can improve the quality of animal welfare and
results, thereby improving the effectiveness,
Correspondence: Paul M. H. Dummer School of Dentistry,
College of Biomedical and Life Sciences, Cardiff University,
Cardiff, UK. (e-mail:dummer@cardif.ac.uk).
International Endodontic Journal, 52, 1253–1254, 2019 © 2019 International Endodontic Journal. Published by John Wiley & Sons Ltd
doi:10.1111/iej.13137
1253