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The Histological Paradox: Methodology and Efficacy of Dental Sectioning

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Within the last two decades, the fields of dental anthropology and bioarchaeology have seen a drastic increase in the number of studies investigating the internal structures of human enamel in archaeological populations. Due to its relatively low cost and preparation time, combined with a high degree of accuracy, destructive histological analysis has become a common methodology in enamel research. However, despite its accuracy and presence within academic literature, institutions often reject applications to perform histological analysis as standard procedure. Most frequently this is justified because destructive analysis negatively impacts future research. As a result, many studies are forced to utilise published data or attempt to access the small number of dental histological slides already in existence. This paper details the processes and procedures followed during histological sampling, with the aim to provide an easily accessible reference for curators allowing them to make more informed decisions regarding requests to conduct histology on samples within their care. Moreover, this paper highlights the preservative methods available to researchers which, when employed, both limit the negative impact to future research and expand the type of material which institutions can provide access to. Access to these new materials provides curators with alternative responses to applications rather than rejecting proposals entirely. Methods include high quality resin casting, which allows for future metric and micro-wear analysis, and digital stitching methods for producing dental cross section databases which institutions can offer access to instead of further destructive sampling.
Content may be subject to copyright.
*Correspondence: cjda2@kent.ac.uk
1 University of Kent
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://doi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Papers from the Institute of Archaeology
The Histological Paradox: Methodology and Efficacy of
Dental Sectioning
Christopher Aris1,*
How to cite: Aris C. ‘The Histological Paradox: Methodology and Efficacy of Dental
Sectioning’. Papers from the Institute of Archaeology, 2020, 29(1): pp. 1–16. DOI:
10.14324/111.2041-9015.011
Published: 06/03/2020
Peer Review:
This article has been peer reviewed through the journal’s standard double-blind review.
Copyright:
© 2020, The Author(s). This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (CC-BY) 4.0 https://creativecommons.org/licenses/by/4.0/, which permits
unrestricted use, distribution and reproduction in any medium, provided the original author and source
are credited • DOI: [https://doi.org/10.14324/111.2041-9015.011].
Open Access:
Papers from the Institute of Archaeology is a peer-reviewed open access journal.
1 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
CONFERENCE PROCEEDINGS, DIGITAL DILEMMA 2018
The Histological Paradox: Methodology and Efficacy of
Dental Sectioning
Christopher Aris
Abstract: Within the last two decades, the fields of dental anthropology and bioarchaeology have
seen a drastic increase in the number of studies investigating the internal structures of human
enamel in archaeological populations. Due to its relatively low cost and preparation time,
combined with a high degree of accuracy, destructive histological analysis has become a common
methodology in enamel research. However, despite its accuracy and presence within academic
literature, institutions often reject applications to perform histological analysis as standard
procedure. Most frequently this is justified because destructive analysis negatively impacts future
research. As a result, many studies are forced to utilise published data or attempt to access the
small number of dental histological slides already in existence. This paper details the processes and
procedures followed during histological sampling, with the aim to provide an easily accessible
reference for curators allowing them to make more informed decisions regarding requests to
conduct histology on samples within their care. Moreover, this paper highlights the preservative
methods available to researchers which, when employed, both limit the negative impact to future
research and expand the type of material which institutions can provide access to. Access to these
new materials provides curators with alternative responses to applications rather than rejecting
proposals entirely. Methods include high quality resin casting, which allows for future metric and
micro-wear analysis, and digital stitching methods for producing dental cross section databases
which institutions can offer access to instead of further destructive sampling.
Keywords: dental sectioning, histology, human variation, sampling permission
Introduction
Dental anthropology is a rapidly expanding field with research spanning the breadth
of primate and hominin evolution, variation, and taxonomy (e.g. Beynon et al. 1991;
Schwartz 2000; Skinner et al. 2008), hominoid dietary variation, (e.g. Martin et al.
2003; Vogel et al. 2008; Lucas et al. 2013; Pampush et al. 2013; Le Luyer et al. 2014;
Le Luyer and Bayle 2017), and the impact of human health on dentition (e.g. Lukacs
1991, 1992, & 1999; Birch and Dean 2014; Primeau et al. 2015). This research relies
on analysis of both external and internal dental features with the study of internal
structures becoming progressively more frequent. Histology is the most commonly
2 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
used method to study internal tooth structures, as a plethora of information can be
gathered through the use of microscopy on histological samples, including: linear,
relative, and average enamel thickness (e.g Suwa and Kono 2005; Smith et al. 2006a;
Reid and Dean 2006; Olejniczak et al. 2008; Mahoney 2010), regional secretion and
growth rates of enamel (e.g. Lacruz and Bromage 2006; Smith et al. 2006b; Mahoney
2008), and enamel periodicity (e.g. Dean et al. 1993; Fitzgerald 1998; Smith et al.
2007; Mahoney 2008). Histology can therefore be seen to provide access to ample
data to justify its use. However, due to the destructive nature of histology, the
method can be unattractive to institutions curating dental material (e.g. museums
and universities) and can lead to the rejection of applications associated with
histology-based research projects. This paper will discuss this issue and how, thanks
to preservative and novel digital techniques, institutions would benefit from
rethinking their policies regarding histological analyses.
While this paper will encourage institutions to consider histological research
proposals, their concerns remain valid. This paper will address institution concerns
by providing alternatives and new methodologies that can be considered when
responding to histological applications. The ethical standards associated with
histological research on archaeological material will also be detailed. These will focus
on guardianship of produced and leftover material, the longevity of sectioned
specimens, and the benefits of histological analysis over non-destructive methods.
Background
The history of histological analysis within anthropology is long and multifaceted,
including the study of extant and extinct hominoids. Since the turn of the century,
many projects have focussed on the analysis of human remains. In the past,
morphology and growth rates of human enamel was thought to be relatively
consistent between populations. However, more recent research has begun to
identify intraspecific variation in enamel thickness measures (e.g. Reid and
Dean 2006; Smith et al. 2006a; Mahoney 2008; Le Luyer and Bayle 2017). These
discoveries have raised questions regarding the extent of intraspecific variation in
human enamel. Such questions can only be answered by conducting more expansive
histological analyses within archaeological and bioarchaeological research projects.
3 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
It is therefore pertinent to review the process of conducting a histological study of
human dentition, detail the modern methodologies associated with such analysis,
and discuss what this means for curators receiving associated applications.
Research into the internal structures of human dentition date back as far as 1873,
with the work of Retzius (1873), and other pioneer studies including Asper (1916)
and Gysi (1931). These early researchers took an ontogenetic approach to dental
analysis, working to outline the growth mechanisms which determine the
composition and structure of human enamel. Where the existence of these
mechanisms correlated with visible internal enamel structures, more recent research
has worked to compare them at an intraspecific level by conducting histological
analyses on archaeological human remains. Reid and Dean (2006) published the
most expansive study of this kind, sampling 326 molars and 352 anterior teeth
(canines and incisors) from five collections, including four archaeological
assemblages. Subsequent analyses revealed a wide range of enamel growth patterns
and enamel thicknesses between the populations (Reid and Dean 2006). Smith et al.
(2006a) identified the first significant intraspecific differences, between similar
interior enamel thickness features and different archaeological populations. Using
data from four of the five populations sampled by Reid and Dean (2006), Smith et
al. (2006a) identified significant differences in the third molar bi-cervical diameters
between South African, Northern American, and Northern English populations
(Smith et al. 2006a). Most recently Le Luyer and Bayle (2017) compared enamel
thickness features of 40 human upper second molars from the Palaeolithic,
Mesolithic, and Neolithic periods. Significant differences were reported in relative
enamel thickness and functional cusp expression between the Early Mesolithic and
Early Neolithic samples, which was suggested to be due to dietary shifts and the
transition to agriculture (Le Luyer and Bayle 2017).
Despite the breadth and volume of the dental histological studies cited above, results
are, for the most part, derived from a relatively small number of histological
collections of human dentition. These consist of a number of small archaeological
samples from a 10th century Slavic cemetery, Spitalfields Crypt (London),
St Gregory’s Priory (Canterbury) and Medieval Denmark and England, and larger
4 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
collections from Northern Europe and Southern Africa (Macho and Berner 1993;
Liversidge 1995; Dean and Scandrett 1996; Schwartz et al. 2001; Reid and
Dean 2006; Smith et al. 2007; Mahoney 2008; 2012). The relatively low number of
populations analysed, and their limited geographic variability, means our
understanding of how they reflect human dental variation is limited. Many internal
dental features which may significantly vary between human populations, particularly
those relating to enamel, can only be accessed through histological methods.
Therefore, future research will invariably require a wider application of histological
methods to archaeological populations. It is therefore important that curators fully
understand the methods and processes associated with histological sampling, and
appreciate its value both to their institution and to ongoing research.
Aims
This paper aims to: (1) Provide an easily comprehendible outline for the process of
histological analysis of human dentition; (2) present an exhaustive list of the data
made available from histological analysis of dental enamel; (3) discuss the better and
lesser-known preservative aspects of histology; (4) and the advantages of institutions
more routinely permitting such analyses on their collections.
Dental histology methodology
Preservative methods
Before any destructive sampling takes places, high resolution pictures are taken for
all aspects and angles of each tooth. Many histological analyses will also include the
production of a 1:1 resin cast using the same methods and materials used in dentistry
(e.g. Mahoney 2008). Casts are produced by creating a dental mould using silicone-
based light body putty (Coltene®). The mould is subsequently filled using a 4:1
hardener and epoxy resin solution (Buehler®), which dries over a 24 hour period to
produce the final cast. Finished casts can be measured against the original tooth by
taking select diameter measures of the crown and root. Where these are not identical,
the casting process is repeated until the required accuracy is achieved. Casts
produced using this method are more durable and easier to curate than the original
tooth (Schmidt 2001).
5 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Destructive stages
Once pictures and casts are produced, teeth are embedded in the same solution of
4:1 hardener and epoxy resin (Buehler®). Next, the embedded samples are cut at a
low speed, most commonly by a diamond-edged wafering blade and a precision
cutter (Buehler® IsoMet), through the required plane (typically longitudinally
through a dental cusp). Cut samples are mounted on glass microscope slides. The
mounted section is cut again so that the material adhered to the slide is around 2-
3 mm thick before being lapped using increasingly fine grinding pads, until between
100-120 µm thick. At this thickness, interior enamel features of enamel formation
can be observed using light microscopy. Accounting for the most common thickness
of wafering blades, and the volume of material destroyed through grinding, sectioned
material will lose between 2-4 mm of material permanently, alongside the remaining
dental material being sectioned into three pieces. Ground sections are then polished
using 0.3 µm aluminium oxide powder, which acts to remove any evidence of
lapping which obscures enamel features. Once polished, samples are placed within
an ultrasonic bath to remove any material debris, and subsequently dehydrated using
progressively higher concentrations of ethanol solutions. Finally the dental samples
are cleared (typically using Histoclear®) and mounted with a glass cover slip. Cover
slips are typically adhered using a mounting medium (DPX®) or an identical 4:1
epoxy resin solution. The use of a cover slip protects dental samples from outside
contaminants and preserves them indefinitely.
6 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Digital methods
Once complete, a histological sample can be observed and analysed under light or
polarised light microscopy. Recently developed software (Olympus cellSens) allows
for stitching methods to be conducted, where microscopic images are tracked and
recorded in live action while a microscope lens is in motion. This produces a
composite image of the whole dental cross-section, with specific save files recording
set scale parameters, allowing the slide to later be accessed and used for data
collection without the need of the slide itself. Enamel features used in
anthropological and bioarchaeological research can be observed under 20x
magnification, and current stitching techniques are accurate to magnifications above
40x. This means that stitching of human enamel sections is adequately reliable for
academic research.
Discussion
Data made available by histology
The above methodologies provide access to the internal structures of dentine and
enamel. These structures allow researchers to measure specific thicknesses of enamel
and their growth rates which cannot be observed from exterior analyses. Thickness
measures have particular value in analysing dietary variation between populations, as
enamel is known to thicken in response to hard or highly wearing diets in hominoids
(e.g. Dumont 1995; Martin et al. 2003; Pampush et al. 2013). However, thickness
measures can also be taken using non-destructive micro computed tomography
(CT). Conversely, growth rates of dentine (Kawasaki et al. 1979) and growth rates
and cross striations of enamel (Boyde 1963; Berkovitz et al. 2002), can only be
accurately measured through histological analyses. These growth lines are highly
regular in their formation and can thus be used to map variation in enamel growth
across dental crowns (e.g. Beynon et al. 1991; Lacruz and Bromage 2006), examine
the influence of external stimuli on enamel growth (e.g. Mahoney 2015), aid in ageing
remains (e.g. Boyde 1963; Antoine et al. 2009), examine the variation in growth
patterns between species (e.g. Schwartz et al. 2001; Smith et al. 2006b), and allow
enamel growth to be calculated at a daily rate (e.g. Beynon et al. 1991; Reid et al.
1998; Lacruz and Bromage 2006). Given the expansion of dental anthropological
research discussed previously, and the wealth of data made available only by
7 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
histological analysis, institutions should strongly consider the importance of
histological analysis when reviewing associated applications to sample material in
their care.
The wide use of histological methods in dental anthropology and bioarchaeology
speaks to its high applicability. However, experience in applying to conduct
histological analysis on human teeth shows that these requests can be rejected due
to the availability of non-destructive alternatives. The most commonly available
alternatives include radiography and micro-CT. In regards to radiography, research
has found it to be significantly less accurate when analysing incremental features and
thickness of teeth. In particular, radiographic analysis has been found to
overestimate the age of enamel mineralisation, and underestimate the time for crown
completion (Beynon et al. 1998). Micro-CT however can analyse teeth to a
comparable accuracy as histology (both to µm) when analysing enamel thickness (e.g.
Le Luyer and Bayle 2017). However, such analyses are exponentially more expensive
and are not widely accessible to many researchers, in particular PhD students and
early career researchers. Moreover, as stated above, micro-CT scans cannot provide
access to all the same data histological methods can. Applications to conduct
histological analyses should therefore still be strongly considered, despite the
existence of non-destructive methods, as these do not always offer accurate or viable
alternatives.
Preservative methods
Despite the preservative measures now taken in modern histological analyses of
human material, it is still undeniably destructive, and curators should take care when
reviewing applications to conduct such methods on valuable biological material.
However, what is evident to those whose research relies on histology is that many
institutions are not informed on the number of preservative methods that are
implemented alongside destructive histological sampling. Moreover, it should be
understood that standard guidelines for histological sampling of dentition permits
only one tooth per individual per project to be sectioned (Mitchell and Brickley
2004). This means no histological project poses a serious destructive risk to any
single set of individual remains.
8 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
One preservative method available is the production of a micro-CT scan of each
tooth before sampling. However, the equipment necessary for this is not widely
available, can be expensive and requires extensive training. As a result, early career
Figure 1: Images depicting the before and after products of histological analysis.
A. Photograph of a Roman maxillary first molar. B. High resolution photograph, with
identification card and scale, of a Medieval first incisor. C. Cross section of the dental crown of
the same Roman molar (A) produced using stitching software at 20x magnification. D. The
remaining embedded material of a Roman canine after histological sectioning. E. Microscopy
image taken from an Anglo-Saxon canine at 20x magnification displaying features of internal
enamel. F. Images of a 1:1 resin cast produced from the dental crown of a Medieval molar before
sectioning.
9 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
researchers and PhD students in particular may not have access to micro-CT
scanning. The method of producing a 1:1 scale dental cast, detailed previously,
provides a more readily available and less expensive preservative method, requiring
less training while retaining precision. While precision is necessary, accurate casts
can be produced with relative ease provided the tooth is thoroughly cleaned and care
is taken to produce a mould which is tight to the sample, encompassing every aspect
of the tooth. If care is taken, the detail of the cast allows future research to accurately
analyse micro-wear patterns, allowing for associated dietary and health studies (e.g.
Schimdt 2001; Mahoney 2007), and the study of external morphology and
morphometrics (e.g. Ferrario et al. 1993; Boaz and Gupta 2009). Alongside
producing additional material which institutions can add to their available
collections, the non-mounted remains of histological sampling can be utilised in
future research. As detailed in figure 1, the mesial and distal aspects of the tooth not
mounted for microscopic analysis remain embedded in resin. The dentine in
particular is viable for subsequent isotopic analysis once cleaned. The use of
embedded dentine material in isotopic analyses can be observed in the literature (e.g.
Beaumont et al., 2013; 2014). The accuracy of the isotopic data produced can vary
according to the thickness of material available, and the reliability can vary according
to the material used for embedding. However, when care is taken to retain and
document embedded material, curating institutions can allow isotopic research and
provide viable material without further destructive analysis on untarnished teeth. All
these methods provide additional material, or uses for returned material, which
institutions can provide access to for future research in addition to the cross-section
slide produced.
The value of digital material must also be emphasised when discussing the products
of histological analysis. Thanks to recent advances in microscopy software, digital
stitching techniques provide a further preservative method which can be utilised
when conducting histological sampling. This increases the accuracy of dental analysis
and furthers the preservation of additional valuable dental material. As discussed
previously, the produced composite images allow researchers to observe the dental
cross section in its entirety. This image can thus be used to take accurate
measurements of multiple dental features using the same program, thereby avoiding
10 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
incurring further error by having to manually create a collage of individually captured
images. When saved in a specific format, these images retain accurate scale
measurements of the sectioned material. This allows future researchers to access the
image and collect more metric and non-metric data without the need of the slide
itself, or most importantly, without needing to section another tooth. When these
images are curated alongside the main collection, this would allow institutions to
offer access to the digital files, thereby avoiding further destructive measures.
Conclusions
While destructive, when histological analysis is implemented alongside digital
techniques it provides affordable access to a wealth of valuable data and produces
both physical and digital resources that can be curated by institutions for future
research. It is also important to note that histological slides remain a part of their
original collection. Any additional materials produced (casts, digital images, etc.) are
also considered a part of the collection and are presented to the curating institution
at the culmination of research. Therefore, the resources made available to
institutions through histological analyses should be considered when reviewing
associated sampling applications, alongside the value of the resulting data. Museums,
universities, and other institutions curating human remains are thereby encouraged
to address their policies regarding histological-based projects. Moreover, it is clear
that both researchers and relevant institutions would benefit from application
systems more willing to approve histological analysis of curated material. A more
open discussion between histologists and curators based on both the potential
volume of novel data, and on the minimal impact their work has on future research,
would greatly benefit both parties and bioarchaeology as a field.
Acknowledgements: I would like to thank the Corinium Museum and the Universities
of Durham and Kent for granting permission to sample the teeth shown here as a part
of my wider research. Further thanks go to Hazel Moxham, Michael Rivera, Cara Hirst,
and Annie Robertson for helping me collect my thoughts for this report. Thanks also
go to the anonymous reviewers for their appreciation of the importance of the topic
and their invaluable feedback.
11 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Competing Interests: The author declared no potential conflicts of interests with
respect to the research, authorship, and/or the publication of this paper.
REFERENCES
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and an evaluation of the most likely sources of error in histological studies of
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DOI: https://doi.org/10.1111/j.1469-7580.2008.01010.x
Asper, H. 1916. Über die ‘‘braune Retzius’sche Parallelsteifung’’ im Schmelz der
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Beaumont, J, Geber, J, Powers, N, Wilson, A, LeeThorp, J & Montgomery, J. 2013.
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Beaumont, J, Gledhill, A & Montgomery, J. 2014. Isotope analysis of incremental
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Berkovitz, B K, Holland, G R & Moxiham, B J. 2002. Oral Anatomy, Histology and
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Beynon, A D, Dean, M C & Reid, D J. 1991. On thick and thin enamel in
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Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
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Dean, M C, Beynon, A D, Reid, D J & Whittaker, D K. 1993. A longitudinal study
of tooth growth in a single individual based on long-and short-period
incremental markings in dentine and enamel. International Journal of
Osteoarchaeology, 3(4): 249-264.
DOI: https://doi.org/10.1002/oa.1390030404
Dumont, E R. 1995. Enamel thickness and dietary adaptation among extant primates
and chiropterans. Journal of Mammalogy, 76(4): 1127-1136. DOI:
https://doi.org/10.2307/1382604
Ferrario, V F, Sforza, C, Miani Jr, A & Serrao, G. 1993. Dental arch asymmetry in
young healthy human subjects evaluated by Euclidean distance matrix
analysis. Archives of Oral Biology, 38(3): 189-194.
DOI: https://doi.org/10.1016/0003-9969(93)90027-J
FitzGerald, C M. 1998. Do enamel microstructures have regular time dependency?
Conclusions from the literature and a large-scale study. Journal of Human
Evolution, 35(4-5): 371-386. DOI: https://doi.org/10.1006/jhev.1998.0232
Gysi, A. 1931. Metabolism in adult enamel. Dental Dig, 37: 661-668.
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human dentine. Archives of oral biology, 24(12): 939-943. DOI:
https://doi.org/10.1016/0003-9969(79)90221-8
Lacruz, R S, & Bromage, T G. 2006. Appositional enamel growth in molars of South
African fossil hominids. Journal of Anatomy, 209(1): 13-20. DOI:
https://doi.org/10.1111/j.1469-7580.2006.00597.x
13 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Le Luyer, M & Bayle, P. 2017. Microevolution of outer and inner structures of upper
molars in Late Pleistocene and Early Holocene humans. Comptes Rendus
Palevol, 16(5-6) : 632-644.
DOI: https://doi.org/10.1016/j.crpv.2016.11.009
Le Luyer, M, Rottier, S & Bayle, P. 2014. Brief communication: Comparative
patterns of enamel thickness topography and oblique molar wear in two early
neolithic and medieval population samples. American Journal of Physical
Anthropology, 155(1): 162-172. DOI: https://doi.org/10.1002/ajpa.22562
Liversidge, H M. 1995. Crown formation times of the permanent dentition and root
extension rate in humans. In: Cecchi, J. M. Aspects of Dental Biology: Palaeontology,
Anthropology and Evolution. Florence: International Institute for the Origin of
Man. pp. 267-275.
Lucas, P W, Omar, R, Al-Fadhalah, K, Almusallam, A S, Henry, A G, Michael, S &
Atkins, A G. 2013. Mechanisms and causes of wear in tooth enamel:
implications for hominin diets. Journal of the Royal Society Interface, 10(80),
20120923. DOI: https://doi.org/10.1098/rsif.2012.0923
Lukacs, J R. 1991. Localized enamel hypoplasia of human deciduous canine teeth:
prevalence and pattern of expression in rural Pakistan. Human Biology, 63(4):
513-512. DOI: https://www.jstor.org/stable/41464196
Lukacs, J R. 1992. Dental paleopathology and agricultural intensification in South
Asia: new evidence from Bronze Age Harappa. American Journal of Physical
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Lukacs, J R. 1999. Enamel hypoplasia in deciduous teeth of great apes: Do
differences in defect prevalence imply differential levels of physiological
stress? American Journal of Physical Anthropology, 110(3): 351-363. DOI:
https://doi.org/10.1002/(SICI)1096-8644(199911)110:3<351::AID-
AJPA7>3.0.CO;2-2
Macho, G A & Berner, M E. 1993. Enamel thickness of human maxillary molars
reconsidered. American Journal of Physical Anthropology, 92(2): 189-200. DOI:
https://doi.org/10.1002/ajpa.1330920208
Mahoney, P. 2007. Human dental microwear from Ohalo II (22,50023,500 cal BP),
Southern Levant. American Journal of Physical Anthropology: The Official
14 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Publication of the American Association of Physical Anthropologists, 132(4): 489-500.
DOI: https://doi.org/10.1002/ajpa.20548
Mahoney, P. 2008. Intraspecific variation in M1 enamel development in modern
humans: implications for human evolution. Journal of Human Evolution, 55(1):
131-147.
DOI: https://doi.org/10.1016/j.jhevol.2008.02.004
Mahoney, P. 2010. Two-dimensional patterns of human enamel thickness on
deciduous (dm1, dm2) and permanent first (M1) mandibular molars. Archives of
Oral Biology, 55(2): 115-126.
DOI: https://doi.org/10.1016/j.archoralbio.2009.11.014
Mahoney, P. 2012. Incremental enamel development in modern human deciduous
anterior teeth. American Journal of Physical Anthropology, 147(4), 637-651. DOI:
https://doi.org/10.1002/ajpa.22029
Mahoney, P. 2015. Dental fast track: prenatal enamel growth, incisor eruption, and
weaning in human infants. American journal of physical anthropology, 156(3): 407-
421. DOI: https://doi.org/10.1002/ajpa.22666
Martin, L B, Olejniczak, A J & Maas, M C. 2003. Enamel thickness and
microstructure in pitheciin primates, with comments on dietary adaptations of
the middle Miocene hominoid Kenyapithecus. Journal of human evolution, 45(5):
351-367. DOI: https://doi.org/10.1016/j.jhevol.2003.08.005
Mitchell, D P & Brickley, M. 2004. Updated Guidelines to the Standard for
Recording Human Remains. Available at:
http://www.babao.org.uk/assets/Uploads-to-Web/14-Updated-Guidelines-
to-the-Standards-for-Recording-Human-Remains-digital.pdf [Last accessed on
30th November 2018]
Olejniczak, A J, Smith, T M, Feeney, R N, Macchiarelli, R, Mazurier, A, Bondioli, L
& Radovčić, J. 2008. Dental tissue proportions and enamel thickness in
Neandertal and modern human molars. Journal of Human Evolution, 55(1): 12-23.
DOI: https://doi.org/10.1016/j.jhevol.2007.11.004
Pampush, James D, Duque, C A, Burrows, B R, Daegling, D J, Kenney & Scott
McGraw, W. 2013. Homoplasy and thick enamel in primates. Journal of Human
Evolution, 64(3): 216-224. DOI: https://doi.org/10.1016/j.jhevol.2013.01.009
Primeau, C, Arge, S O, Boyer, C & Lynnerup, N. 2015. A test of inter-and intra-
observer error for an atlas method of combined histological data for the
15 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
evaluation of enamel hypoplasia. Journal of Archaeological Science: Reports, 2, 384-
388. DOI: https://doi.org/10.1016/j.jasrep.2015.03.007
Reid, D J & Dean, M C. 2006. Variation in modern human enamel formation
times. Journal of Human Evolution, 50(3): 329-346.
DOI: https://doi.org/10.1016/j.jhevol.2005.09.003
Reid, D J, Beynon, A D, & Ramirez Rozzi, F V R. 1998. Histological reconstruction
of dental development in four individuals from a medieval site in Picardie,
France. Journal of Human Evolution, 35(4-5): 463-477.
DOI: https://doi.org/10.1006/jhev.1998.0233
Retzius, A. 1837. Bemerkungen über den inneren Bau der Zähne. mit besonderer
Rücksicht auf dem in Zahnknochen vorkommenden Röhrenbau. (Müllers)
Archive of Anatomy and Physiology, 1837, 486-566.
Schmidt, C W. 2001. Dental microwear evidence for a dietary shift between two
nonmaize-reliant prehistoric human populations from Indiana. American
Journal of Physical Anthropology, 114(2): 139-145.
DOI: https://doi.org/10.1002/1096-8644(200102)114:2<139::AID-
AJPA1013>3.0.CO;2-9
Schwartz, G T. 2000. Taxonomic and functional aspects of the patterning of enamel
thickness distribution in extant large-bodied hominoids. American Journal of
Physical Anthropology, 111(2): 221-244.
DOI: https://doi.org/10.1002/(SICI)1096-8644(200002)111:2<221::AID-
AJPA8>3.0.CO;2-G
Schwartz, G T, Reid, D J, & Dean, C. 2001. Developmental aspects of sexual
dimorphism in hominoid canines. International Journal of Primatology, 22(5):
837-860. DOI: https://doi.org/10.1023/A:1012073601808
Skinner, M M, Gunz, P, Wood, B A & Hublin, J J. 2008. Enamel-dentine junction
(EDJ) morphology distinguishes the lower molars of Australopithecus
africanus and Paranthropus robustus. Journal of Human Evolution, 55(6): 979-
988. DOI: https://doi.org/10.1016/j.jhevol.2008.08.013
Smith, T M, Olejniczak, A J, Reid, D J, Ferrell, R J & Hublin, J J. 2006a. Modern
human molar enamel thickness and enameldentine junction shape. Archives of
Oral Biology, 51(11): 974-995.
DOI: https://doi.org/10.1016/j.archoralbio.2006.04.012
16 C. Aris
Gardner, A and Harrison, R 2017 Brexit, Archaeology and Heritage: Reections and
Agendas.
Papers from the Institute of Archaeology
,
27(1): Art. 28, pp. 1–2, DOI:
https://d oi.org/10.5334/pia-548
Closing Comment
We would like to thank the respondents
to our paper for their contributions to the
unfolding debate over Brexit and its rela-
tionship to archaeology and heritage. These
essays reflect in diverse ways the complex
intersection of the scholarly, the political and
the personal that has perhaps always been
with us, and increasingly commented upon,
but which Brexit has brought to a moment of
crisis from which we can only hope a positive
outcome is still salvageable. Since writing the
initial paper for this Forum in July of 2017,
events have moved forward in several ways,
although ironically in terms of the actual pro-
cess of exiting the EU remarkably little has
happened. More and more evidence is cer-
tainly emerging of the social and economic
problems that this process, should it reach
conclusion, will cause, whether in UK gen-
erally, in the rest of Europe (particularly in
Ireland; e.g. House of Lords 2016; The UK in a
Changing Europe 2017), or in our particular
sector (Schlanger 2017). More disturbingly,
perhaps, the tone of debate represented
in some media outlets has darkened even
further and universities in particular have
come under attack as bastions of ‘remain-
erism’. Just prior to writing this piece, the
Conservative politician Chris Heaton-Harris
MP was in the news for seeking information
about the teaching of Brexit-related issues in
all UK universities (BBC 2017a). Whatever the
motivation behind this, the front cover of the
Daily Mail on October 26th (headline, ‘Our
Remainer Universities’) followed up on this
story, and made it clear that for some on the
pro-Leave right-wing, universities are now
a major target for political attack. This can
be seen as part of a wider trend, pre-dating
the referendum and becoming widespread
across the western world (and certainly in
the US), of right-wing populists painting
universities – and, by extension, academic
and scientific knowledge – as simultaneously
liberal/left-biased and elitist (cf. Runciman
2016). Meanwhile, these same populist
movements appear to be, literally, on the
march, from Charlottesville in August (BBC
UCL Institute of Archaeology, GB
Corresponding author: Andrew Gardner
(andrew.gardner@ucl.ac.uk)
FORUM
Brexit, Archaeology and Heritage:
Reections and Agendas
Andrew Gardner and Rodney Harrison
This short report represents the closing comments to the forum covering Brexit,
Archaeology and Heritage.
Keywords: Archaeology; Brexit; Heritage; Funding; EU; Post-Truth
Smith, T M, Olejniczak, A J, Tafforeau, P, Reid, D J, Grine, F E & Hublin, J J.
2006b. Molar crown thickness, volume, and development in South African
Middle Stone Age humans. South African Journal of Science, 102(11-12): 513-517.
DOI: https://doi.org/10.1016/j.archoralbio.2006.04.012
Smith, T M, Reid, D J, Dean, M C, Olejniczak, A J, Ferrell, R J & Martin, L B. 2007.
New perspectives on chimpanzee and human molar crown development. In:
Bailey, S. E. and Hublin, J. J. Dental Perspectives on Human Evolution: State of the
Art Research in Dental Paleoanthropology. Dordrecht: Springer, pp. 177-192.
Suwa, G. E. N., & Kono, R. T. 2005. A micro-CT based study of linear enamel
thickness in the mesial cusp section of human molars: reevaluation of
methodology and assessment of within-tooth, serial, and individual
variation. Anthropological Science, 113(3): 273-289.
DOI: https://doi.org/10.1537/ase.050118
Vogel, E R, van Woerden, J T, Lucas, P W, Atmoko, S S U, van Schaik, C P &
Dominy, N. J. 2008. Functional ecology and evolution of hominoid molar
enamel thickness: Pan troglodytes schweinfurthii and Pongo pygmaeus
wurmbii. Journal of Human Evolution, 55(1): 60-74.
DOI: https://doi.org/10.1016/j.jhevol.2007.12.005
... This is especially pertinent given the use of Retzius periodicity (and associated perikymata counts) to investigate inter-species difference and evolutionary trajectories via dental analysis (e.g. Bocaege & Humphrey, 2016;Guatelli-Steinberg & Reid, 2010;Guatelli-Steinberg et al., 2018;Guatelli-Steinberg, Reid, Bishop, & Larsen, 2005;Modesto-Mata et al., 2017, 2020Ramirez Rozzi & Bermudez de Castro, 2004). Recent research has highlighted that Retzius periodicity can vary significantly between populations. ...
... One-to-one scale resin casts, followed by high resolution images, were produced before any destructive sampling was undertaken for each tooth analysed (Aris, 2020). Following this, standard thin section histological methods were used to produce a slide for each tooth, in order to implement polarised light microscopy (e.g. ...
... Following this, standard thin section histological methods were used to produce a slide for each tooth, in order to implement polarised light microscopy (e.g. Aris, 2020;Mahoney, 2008;Schwartz & Dean, 2005). ...
Article
Objective This study explored differences in the regional daily growth rates of human enamel between tooth types across a temporal transect in Britain. Methods Upper permanent central incisors (n = 81), upper permanent canines (n = 69), and upper and lower permanent first molars (n = 115) from Roman, Pre-Medieval, Medieval, and Modern day populations were analysed using histological methods. Daily secretion rates (DSRs) were collected for inner, mid, and outer regions of cuspal and lateral enamel for each tooth type and temporal sample. Variation in DSRs between the tooth types, within each population, was sought using Welch’s tests. Results Numerous significant differences were observed in DSRs between equivalent enamel regions of different tooth types. The majority of differences were observed between molars and the anterior teeth, but there were no obvious trends as to which typically grew faster/slower, nor was there any consistency across the temporal samples. In contrast, comparisons between incisors and canines yielded minimal differences and variation, when significant, was found to be enamel area- and sample-specific. Conclusions This study presents evidence for a high level of variation in DSRs between anterior teeth and first molars of the permanent dentition. This variation appears sporadic with no clear trend outside of anterior tooth comparisons, where analyses of the Late Pre-Medieval and Modern-day populations highlight how DSRs within cuspal and lateral enamel can vary independently.
... In these more recent analyses the use of comparative data sets from the pooled representative samples are limited in their utility (e.g., Aris et al., 2020b). In addition, while the production of new samples is useful to the field of dental anthropology, its destructive nature should be considered and pre-existing material used where possible and appropriate to help preserve dental remains wherever possible (Aris, 2020). ...
... The Pre-Medieval period in Thanet is associated with newly developing urban areas following Roman occupation (McKinley et al., 2015). Similar guides to these populations' context can be found in articles by Aris andcolleagues (2020a, 2020b). ...
... Before any tooth was sectioned as a part of producing the data set, resin casts were produced for each incisor, canine and molar using standard methods (Aris, 2020). Producing casts in this way allows for the reproduction of the surface morphology of dental crown, thus allowing for future researchers to analyse features not within the data such, such as crown morphology, microwear, and enamel surface features including perikymata and linear enamel hypoplasia. ...
Article
Full-text available
This article represents an open repository of human enamel data collected/reconstructed from seven populations covering a 2000 year time period in Britain via five temporally distinct periods. In total data was collected from 285 permanent teeth, including maxillary and mandibular first molars, and maxillary canines and first incisors. Data was gathered through thin histological methods using standard procedures for sectioning human dental material. In regards to enamel growth, data is collected for daily secretion rates (DSRs) for the inner, mid, and outer areas of lateral and cuspal enamel. For enamel thickness average (AET) and relative (RET) enamel thickness, cuspal linear thickness (CT), and lateral linear thickness (LT) was collected. Alongside the data presented this article also provides clear and transparent explanations for all the methods involved in its production, in order to ensure understanding of the rigorous protocol and consistency associated with the data provided. The novel data is also contextualised with a compilation of equivalent data published in past articles.
... Resin casts were produced for each incisor prior to any destructive analysis, and were produced using standard methods (Aris, 2020). The casts reproduced the surface morphology of the tooth crown allowing for future study of microwear, crown morphology, and enamel surface features including linear enamel hypoplasia and perikymata. ...
... Thin sections were produced using standard histological procedures (e.g. Schwartz et al., 2005;Mahoney, 2008;Aris, 2020). The incisors were embedded in an epoxy resin and hardener mixture (Buehler ® ) to minimise the chance of the teeth fracturing during sectioning. ...
Article
Full-text available
This study investigates enamel growth of a modern-day human upper first incisor (S197) possessing an accessory cusp. Growth rates collected from the accessory enamel are compared to data collected from the primary cusp and healthy incisors from the same population. Upper first incisors (n=12) and S197 were analysed using histological methods. Daily secretion rates (DSRs) were calculated for inner, mid, and outer regions of cuspal and lateral sites. Additional DSRs were calculated for equivalent regions of S197’s accessory cusp. S197’s primary cusp DSRs were significantly faster than the accessory cusp for all lateral regions, but significantly slower in the inner and mid cuspal regions. S197’s primary cusp DSRs were also significantly faster than the healthy incisor sample for all lateral regions, but significantly slower in the inner and mid cuspal regions. The DSRs of the healthy sample were significantly faster than those of S197’s accessory cusp for all lateral regions, but significantly slower in the inner cuspal region. This case study displays that human teeth possessing accessory cusps can present varying DSRs to healthy teeth of the same population, and that accessory enamel growth may not follow the same pattern of increasing DSRs along the length of enamel prisms.
... Before conducting destructive analysis, high resolution images and one-to-one scale resin casts were produced for each tooth (Aris, 2020). ...
... Standard histological methods were used to produce thin sections for each tooth (e.g., Aris, 2020;Mahoney, 2008;Schwartz & Dean, 2005). First, each tooth was embedded in a four-to-one hardener and epoxy resin solution (Buehler ® ). ...
Article
Full-text available
Objective This study explored biological sex differences in the regional daily growth rates of human anterior enamel from modern and ancient populations in Britain. Methods Maxillary permanent incisors (n = 80) and canines (n = 69) from Roman, Anglo‐Saxon, Medieval, and Modern day populations were analyzed using histological methods. Daily secretion rates (DSRs) were collected for inner, mid, and outer regions of cuspal and lateral enamel. Modern day samples were of known sex, archeological individuals had sex determined using standard osteological methods. Variation in DSRs between the sexes, both between and within populations, was sought using parametric and nonparametric tests. Results When all samples were pooled, there was no significant difference between males and females. Similarly no significant differences in DSRs were identified between male and females within each population. When DSRs were compared between the populations, DSRs decreased from the more ancient to the more recent populations for males, and for females. More interpopulation differences were observed in males. Discussion This study presents evidence for the relative consistency of enamel DSRs between male and female groups within each British population. Interpopulation analyses found DSRs slowed significantly between Roman and modern day populations for both sexes, with male DSRs showing the greatest variation between populations.
Article
Full-text available
The histological identification of interglobular dentine (IGD) in archeological human remains with macroscopic evidence of rickets has opened a promising new avenue for the investigation of metabolic disease in the past. Recent paleopathological studies have shown that histological analysis of archeological human teeth may allow the identification of periods of vitamin D deficiency occurring within very narrow developmental windows, yielding new information on the seasonality or even maternal-fetal transmission of this disease. However, currently available techniques for recording IGD rely on subjective scoring systems or visual estimations, potentially leaving them open to inter and intra-observer error and rendering comparisons of datasets difficult. Here we describe a new imaging protocol that utilizes open access software and may yield more objective and quantitative data on the amount of IGD present within a dentinal region of interest. We demonstrate that grayscale histograms in FIJI®/ImageJ® might be used to provide less subjective estimates of the percentage of a region of interest affected by IGD. Application of this technique may enable more accurate comparison of datasets between researchers.
Article
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Objectives: This study explores variation and trends in first molar enamel thickness and daily enamel secretion rates over a 2000 year period in Britain. Methods: Permanent first molars (n = 89) from the Roman, Anglo-Saxon, and Medieval periods, as well as modern-day Britain, were analyzed using standard histological methods. Relative enamel thickness (RET) and linear measurements of cuspal and lateral thickness were calculated for mesial cusps. Daily secretion rates (DSRs) were calculated for inner, mid, and outer enamel regions in both cuspal and lateral enamel. Significant differences and trends were identified between samples using nonparametric statistical tests. Results: Enamel thickness differed between some populations, but no temporal trends were identified. Early Anglo-Saxon molars had significantly thinner RET than both Late Anglo-Saxon (p < .00) and Medieval (p < .00) molars. Lateral enamel from the Roman molars was significantly thinner than the modern-day sample (p = .04). In contrast, a significant slowing trend in DSRs was observed across the more ancient to modern-day samples in every measured region except the mid-lateral enamel region. Discussion: This study presents the first evidence for a gradual slowing in the daily rate that enamel is secreted in molars over the past 2000 years in Britain. However, this trend was not matched by consistent or significant positive or negative shifts in enamel thickness. These findings suggest that modern human molars of similar enamel thickness, from different modern and ancient populations, formed at different rates.
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Correlation between the timing of permanent first molar eruption and weaning age in extant primates has provided a way to infer a life history event in fossil species, but recent debate has questioned whether the same link is present in human infants. Deciduous incisors erupt at an age when breast milk can be supplemented with additional foods (mixed feeding), and weaning is typically complete before permanent first molars erupt. Here, I use histological methods to calculate the prenatal rate by which enamel increases in thickness and height on human deciduous incisors, canines, and molars (n = 125). Growth trajectories for each tooth type are related to the trimesters and assessed against the eruption sequence and final crown height. Analyses show that central incisors initiate early in the second trimester with significantly faster secretion rates relative to canines and second molars, which initiate closer to birth. Even though initial extension rates were correlated with crown height and scaled with positive allometry within each tooth class, the relatively short incisors still increased in height at a significantly faster rate than the taller canines and molars. The incisor prenatal "fast track" produces a greater proportion of the crown before birth than all other tooth types. This growth mechanism likely facilitates early incisor eruption at a time when the mixed feeding of infants can be initiated as part of the weaning process. Findings provide a basis from which to explore new links between developmental trends along the tooth row and mixed feeding age in other primates. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.
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Enamel thickness has been linked to functional aspects of masticatory biomechanics and has been demonstrated to be an evolutionary plastic trait, selectively responsive to dietary changes, wear and tooth fracture. European Late Paleolithic and Mesolithic hunter-gatherers mainly show a flat wear pattern, while oblique molar wear has been reported as characteristic of Neolithic agriculturalists. We investigate the relationships between enamel thickness distribution and molar wear pattern in two Neolithic and medieval populations. Under the assumption that dietary and/or non-dietary constraints result in directional selective pressure leading to variations in enamel thickness, we test the hypothesis that these two populations will exhibit significant differences in wear and enamel thickness patterns. Occlusal wear patterns were scored in upper permanent second molars (UM2) of 64 Neolithic and 311 medieval subadult and adult individuals. Enamel thickness was evaluated by microtomography in subsamples of 17 Neolithic and 25 medieval individuals. Eight variables describing enamel thickness were assessed. The results show that oblique molar wear is dominant in the Neolithic sample (87%), while oblique wear affects only a minority (42%) of the medieval sample. Moreover, in the Neolithic molars, where buccolingually directed oblique wear is dominant and greatest enamel lost occurs in the distolingual quadrant, thickest enamel is found where occlusal stresses are the most important-on the distolingual cusp. These results reveal a correlation between molar wear pattern and enamel thickness that has been associated to dietary changes. In particular, relatively thicker molar enamel may have evolved as a plastic response to resist wear. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.
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Knowledge of deciduous crown formation times is useful in forensic anthropology and when aging juvenile remains from an archaeological context. Until now, histological techniques for calculating enamel formation times in deciduous teeth have been completely dependent on being able to visualise clear daily incremental markings. In the first part of this study we took twenty deciduous teeth where daily incremental markings were easily visible on both aspects of the crown and used these as the basis for generating regression equations to predict enamel formation times. We were then able to use these regression equations to calculate deciduous crown formation times in a further fifty deciduous teeth where it was not possible to see daily increments. We present here new data for deciduous crown formation times based on these regression equations. In the second part of this study these regression formulae were applied blind to teeth from two individuals with known medical histories. The formulae were able to successfully determine the times of prenatal and postnatal enamel formation relative to the neonatal line and also to correctly estimate the ages at which accentuated ‘stress lines’ occurred during the period of deciduous crown formation.
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Enamel thickness was investigated in the mesial cusp section of 167 unworn human molars by means of non-destructive micro-CT based methodology. Serial sections of the entire crown were taken at a voxel resolution of 28 microns, and the initial volume data set of each molar was standardized in orientation to obtain a vertical section that accurately contains the dentine tips of the two mesial cusps. Enamel thickness at the cusp tips, occlusal basin, and lateral crown face was measured in the mesial cusp section and in sections offset from that section by 0.6 mm. We found that thickness at the cusp tips may be overestimated in offset sections by up to about I mm, and those of the occlusal basin overestimated or underestimated by up to about 0.5 mm. We also found that maximum 'radial' thickness of the lateral crown face was least affected by section position, usually with discrepancies of less than about 0.1-0.2 mm. In all serial positions in both upper and lower molars, a 'functional' (lingual in uppers and buccal in lowers) to 'non-functional' side gradient in enamel thickness was observed in cusp tip, occlusal basin, and lateral crown face enamel, with the exception of the characteristically thin enamel at the protoconid and paracone cusp tips. Serial differences in thickness were seen between the thinner M1 and the two posterior molars in many but not all measures of thickness, the pattern of which appears to be influenced by the thin M I mesiobuccal cusp enamel. Individual variation of maximum lateral thickness, the least variable measure of thickness, was found to be substantial (a 30-60% range) even with serial and buccolingual positions controlled. Correlation between whole crown average enamel thickness and maximum lateral thickness was high, indicating that the latter is a potentially useful predictor of overall enamel thickness of the molar crown. The present results indicate that interspecific comparisons of enamel thickness must be made with careful attention to positional placement of thickness measures, potential serial differences, and intraspecific variation.