Quick Tips: Identifying Dental Diseases – Dental/Enamel Hypoplasia.

In our previous Quick Tip post on identifying dental diseases, we gave a basic overview on the different diseases that are observed. If you haven’t read it, you can find it by clicking here.

Dental hypoplasia is a condition that affects the enamel of a tooth. It is characterised by pits, grooves and transverse lines which are visible on the surface of tooth crowns. The lines, grooves and pits that are observed are defects in the enamels development. These defects occur when the enamel formation, also known as amelogenesis, is disturbed by a temporary stress to the organism which upsets the ameloblastic activity. Factors which can cause such stress and therefore disrupt the amelogenesis include; fever, malnutrition, and hypocalcemia.

Figure 1: An example of linear enamel hypoplasia.

Figure 1: An example of linear enamel hypoplasia.

It has been noted that enamel hypoplasia is more regularly seen on anterior teeth than on molars or premolars, and that the middle and cervical portions of enamel crowns tend to show more defects than the incisal third. This is due to the amelogenesis beginning at the occlusal apex of each tooth crown and proceeding rootward, towards where the crown then meets the root at the cervicoenamel line.

Figure 2: Anatomy of a tooth. Note the top third is known as either the occlusal third if in molars, or the incisal third when the tooth is an incisor or canine.

Figure 2: Anatomy of a tooth. Note the top third is known as either the occlusal third if in molars, or the incisal third when the tooth is an incisor or canine.

By studying these incidents of enamel hypoplasia within a population sample, we can be provided with valuable information regarding patterns of dietary stress and disease that may have occurred within the community.

References:

Lukacs, J.R. 1989. Dental paleopathology: methods for reconstructing dietary patterns. In M.Y. Iscan and K.A.R. Kennedy (eds), Reconstruction of life from the skeleton. New York, Alan Liss, pp. 261-86.

Ubelaker, D.H. 1989. Human Skeletal Remains: Excavation, Analysis, Interpretation (2nd Ed.). Washington, DC: Taraxacum.

White, T.D., Folkens, P.A. 2005. The Human Bone Manual. San Diego, CA: Academic Press. Pg 392-398.

This is the second post of the Quick Tips series on identifying dental diseases. The next post in this series will focus on how to identify dental caries and highlight the cause of this dental disease.

To read more Quick Tips in the meantime click here, or to learn about basic fracture types and their characteristics/origins click here!

Advertisements

Textbook of the Week: Forensic Archaeology Advances in Theory and Practice.

Every week we highlight one archaeology/anthropology textbook from our suggested readings, a full list of our suggested resources can be found here, on our Useful Literature page.

5191V5QW55L._SY344_BO1,204,203,200_

Forensic Archaeology Advances in Theory and Practice (UK/Europe Link)
Forensic Archaeology Advances in Theory and Practice (US/Worldwide Link)
by John Hunter & Margaret Cox. Rating: ****

“This text book is easy to follow, so perfect for beginners or first year students. It uses numerous case studies and illustrations to show you how to apply it in practice, meaning that you can fully grasp what situation to use it in and how to correctly apply it.

If you’re a student – check out our ‘Quick Tips’ posts where we breakdown topics of AAFS into bite-sized chunks. We’re currently covering how to age and how to estimate the biological sex of skeletal remains, and also how to identify dental diseases!

Quick Tips: Identifying Dental Diseases – The Basics.

Quick Tips: Identifying Dental Diseases – The Basics.

In a previous Quick Tip post we briefly touched on teeth in anthropology/archaeology by providing a basic answer to the question, “What can an anthropologist tell from the examination of teeth?”, which can be found by clicking here.

“No structures of the human body are more likely to disintegrate during life than teeth, yet after death none have greater tenacity against decay” – Wells, 1964.

Teeth are the hardest and most chemically stable tissues in the body; because of this, they’re sometimes the only part of a skeletal remain to withstand the excavation. Even though teeth are the most robust structures of a skeleton, there are numerous diseases that can affect them. This is due to teeth interacting directly with the environment and therefore are vulnerable to damage from physical and biological influences. It is from these diseases, that archaeologists and anthropologists can learn a wealth of information on an individual or population’s diet, oral hygiene, dental care and occupation.

Lukacs, 1989, classified dental diseases into four categories, which are;

  • Infectious – This is one of the more common disease types found within archaeological populations. An example of an infectious dental disease is caries.
  • Degenerative – This is where the dental disease occurs over time as the person ages. An example of degenerative dental disease includes recession of the jaw bone.
  • Developmental –These dental diseases develop due to environmental and lifestyle factors, such as malnutrition. An example of this type of disease is enamel hypoplasia.
  • Genetic – These types of diseases are caused by genetic anomalies.

The main dental diseases that are observed within an archaeological or anthropological context are;

If the dental disease listed above is a link, it means that I have already covered it in an individual blog post and can be found by following the link.

Each of these dental diseases has their own characteristics which allows them to be easily distinguished from one and another. In the next few posts of this Quick Tips series, we will be focusing on each dental disease individually, and highlighting their aetiology and physical characteristics.

References:

Buikstra, J.E., Ubelaker, D.H. 1994. Standards for Data Collection From Human Skeletal Remains. Fayetteville, Arkansas: Arkansas Archaeological Survey Report Number 44.

Lukacs, J.R. 1989. Dental paleopathology: methods for reconstructing dietary patterns. In M.Y. Iscan and K.A.R. Kennedy (eds), Reconstruction of life from the skeleton. New York, Alan Liss. Pg 261-86.

Ubelaker, D.H. 1989. Human Skeletal Remains: Excavation, Analysis, Interpretation (2nd Ed.). Washington, DC: Taraxacum.

Wells, C. 1964. Bones, bodies and disease. London, Thames and Hudson.

White, T.D., Folkens, P.A. 2005. The Human Bone Manual. San Diego, CA: Academic Press. Pg 392-398.

This is the first post of the Quick Tips series on identifying dental diseases. The next post in this series will focus on how to identify dental/enamel hypoplasia and highlight the cause of this dental disease.

To read more Quick Tips in the meantime, click here, or to learn about basic fracture types and their characteristics/origins click here!

Quick Tips: How to Estimate the Biological Sex of a Human Skeleton – Pelvic Dimorphism.

This is the 3rd blog post in this Quick Tips series on estimating the biological sex of human skeletal remains. If you haven’t read the first post on the basics of sexing skeletal remains, click here to start at the beginning or if you skipped the 2nd post focusing on the skull method if sex estimation, click here.

When it comes to sexing skeletal remains by the pelvic elements there are a few trends, as stated in the first blog post in this series, the female pelvic bones, specifically the sacra and ossa coxa are smaller and less robust than their male counterparts.

Figure 1: Side by side size comparison of a male (left) and female (right) pelvis.

Figure 1: Side by side size comparison of a male (left) and female (right) pelvis.

Although the female pelvic components are smaller in general, many aspects of the female pelvis are wider than males. The pelvic inlets on a female are relatively wider than those of males, as well as the greater sciatic notches – which is thought to aid childbirth.

Figure 2: Basic annotated diagram of the pelvis.

Figure 2: Basic labelled diagram of the pelvic anatomy.

There are numerous features of the pelvic bones that are examined to identify the biological sex of an individual, alongside the trends stated about. These features are as follows;

  • The ventral arc.
  • The subpubic concavity.
  • The medial aspect of the ischiopubic ramus.
  • The greater sciatic notch.

The first three features listed above, are known as the Phenice method – which was proposed by T. W. Phenice in 1969. His paper, “A Newly Developed Visual Method of Sexing the Os Pubis”, contributed greatly to the method of visual determination of sex, as beforehand the methods were subjective and based largely on the osteologist’s experience. The Phenice method should only be used for fully adult skeletal remains, where it is 96 to 100% accurate.

The ventral arc is a slightly raised ridge of bone that sweeps inferiorly and laterally across the central surface of the pubis. It joins with the medial border of the ischiopubic ramus. The ventral arc is only present in females, although males may have raised ridges in this area, but these do not take the wide, evenly arching appearance of the ventral arc.

Figure 2: The ventral arc is characterised by a slightly raised ridge of bone. Males do not exhibit the ventral arc, where as females do.

Figure 3: The ventral arc is characterised by a slightly raised ridge of bone. Males (left) do not exhibit the ventral arc, where as females (right) do.

To observe the subpubic concavity, you should turn the pubis so that the convex dorsal surface if facing you. Then you should view the medial edge of the ischiopubic ramus. Females display a subpubic concavity here where the edge of the ramus is concaved, whereas males tend to have straight edges or very slightly concaved.

Figure 4: Females display a subpubic concavity here where the edge of the ramus is concaved, whereas males tend to have straight edges or very slightly concaved.

Figure 4: Females (right) display a subpubic concavity here where the edge of the ramus is concaved, whereas males (left) tend to have straight edges or very slightly concaved.

To observe the medial aspect of the ischiopubic ramus, you should turn the pubis 90° so that the symphyseal surface is directly facing you. View the part of the ramus that is directly inferior to the pubis symphysis. In females, the ramus has a sharp, narrow edge, whereas in males it is flat and blunt.

Figure 5: In females (right), the medial aspect of the ischiopubic ramus has a sharp, narrow edge, whereas in males (left) it is flat and blunt.

Figure 5: In females (right), the medial aspect of the ischiopubic ramus has a sharp, narrow edge, whereas in males (left) it is flat and blunt.

As with the five features of the skull used to sex a skeleton in the previous, the greater sciatic notch has also been given a numerical score from 1 to 5 relating to the level of expression. It has been generally found that female os coxae are more likely to exhibit a lower level of expression, whereas male os coxae are more likely to have higher levels of expression.

Figure 6:

Figure 6: It has been generally found that female os coxae are more likely to exhibit a lower level of expression, whereas male os coxae are more likely to have higher levels of expression, when it comes to the greater sciatic notch.

To obtain the best results whist examining the os coxae, it should be held in the same orientation as the pictured above. This allows you to match the angle of the greater sciatic to the closest expression that represents it. It should be noted that this method is usually used as a secondary indicator.

References:

Buikstra, J.E., Ubelaker, D.H. 1994. Standards for Data Collection From Human Skeletal Remains. Fayetteville, Arkansas: Arkansas Archaeological Survey Report Number 44.

Ubelaker, D.H. 1989. Human Skeletal Remains: Excavation, Analysis, Interpretation (2nd Ed.). Washington, DC: Taraxacum.

White, T.D., Folkens, P.A. 2005. The Human Bone Manual. San Diego, CA: Academic Press. Pg 392-398.

This is the third post of the Quick Tips series on sex determination of skeletal remains. The next post in this series will focus on the use of DNA to determine biological sex. To read more Quick Tips in the meantime, click here

Textbook of the Week: Archaeology in Practice.

Every week we highlight one archaeology/anthropology textbook from our suggested readings, a full list of our suggested resources can be found here, on our Useful Literature page.

ImageArchaeology in Practice: A Student Guide to Archaeological Analyses (UK/Europe Link)

Archaeology in Practice: A Student Guide to Archaeological Analyses (US/Worldwide Link)

by Jane Balme and Alistair Paterson. Rating: ****

“This is THE book for how to apply archaeological methods in real life contexts. It is easy to follow, so perfect for first year students as it uses numerous case studies and illustrations to show you how to apply it in practice. I used this during my studies to wrap my head around how methods can be applied – which helped when methods were only briefly discussed in theory during my lectures.”

If you’re new to the realm of archaeological, anthropological and forensic sciences (AAFS), or are a student needing sturdy and reliable references, or wondering “what archaeology or anthropology textbooks to buy? Check out our new ‘Useful Literature’ page!

Image

Textbook of the Week: Archaeology of Disease.

Every week we highlight one archaeology/anthropology textbook from our suggested readings, a full list of our suggested resources can be found here, on our Useful Literature page.

ImageThe Archaeology of Disease (UK/Europe)

The Archaeology of Disease (US/Worldwide Link)
(Click the links to have a peek inside the book)

by Charlotte Roberts and Keith Manchester. Rating: *****

“This is a essential if you’re studying diseases or taphonomy. It is fully illustrated with amazing case studies to display all diseases – ranging from simple fractures to malnutrition and infections.
Brilliant book, helped me a lot with my university Anthropology unit where I had to examine a bone and conclude which illness it had.”

If you’re new to the realm of archaeological, anthropological and forensic sciences (AAFS), or are a student needing sturdy and reliable references, or wondering “what archaeology or anthropology textbooks to buy? Check out our new ‘Useful Literature’ page!

Image

Textbook of the Week: Archaeology: Theories, Methods & Practice.

Every week we highlight one archaeology/anthropology textbook from our suggested readings, a full list of our suggested resources can be found here, on our Useful Literature page.

ImageArchaeology: Theories, Methods and Practice (UK/Europe Link)

Archaeology Essentials: Theories, Methods, and Practice (Second Edition) (US/Worldwide Link)

by Colin Renfrew and Paul Bahn. Rating: *****

“This book is highly acclaimed and is the ultimate archaeology bible for students, or people new to archaeology and want to get stuck right in. After being recommended it by two of my University lecturers, I took it out from the library to use for my assignments so many times I ended up buying it.”

If you’re new to the realm of archaeological, anthropological and forensic sciences (AAFS), or are a student needing sturdy and reliable references, or wondering “what archaeology or anthropology textbooks to buy? Check out our new ‘Useful Literature’ page!

Image