Navigation Links
Reptilian root canal: U of T Mississauga study reveals infection in jaw of ancient fossil

A reptile that lived 275-million years ago in what is now Oklahoma is giving paleontologists a glimpse of the oldest known toothache.

Led by Professor Robert Reisz, the chair of the Department of Biology at the University of Toronto Mississauga, scientists found evidence of bone damage due to oral infection in Paleozoic reptiles as they adapted to living on land. Their findings, published online in the journal Naturwissenschaften The Nature of Science, predate the previous record for oral and dental disease in a terrestrial vertebrate by nearly 200 million years.

"Not only does this fossil extend our understanding of dental disease, it reveals the advantages and disadvantages that certain creatures faced as their teeth evolved to feed on both meat and plants," says Reisz. "In this case, as with humans, it may have increased their susceptibility to oral infections."

The researchers investigated the jaws of several well-preserved specimens of Labidosaurus hamatus, a 275-million-year-old terrestrial reptile from North America. One specimen stood out because of missing teeth and associated erosion of the jaw bone. With the aid of CT-scanning, Reisz and colleagues found evidence of a massive infection. This resulted in the loss of several teeth, as well as bone destruction in the jaw in the form of an abscess and internal loss of bone tissue.

As the ancestors of advanced reptiles adapted to life on land, many evolved dental and cranial specializations to feed more efficiently on other animals and to incorporate high-fiber plant leaves and stems into their diet. The primitive dental pattern in which teeth were loosely attached to the jaws and continuously replaced, changed in some animals. Teeth became strongly attached to the jaw, with little or no tooth replacement. This was clearly advantageous to some early reptiles, allowing them to chew their food and thus improve nutrient absorption. The abundance and global distribution of Labidosauris and its kin suggest that it was an evolutionary success.

However, Reisz and his colleagues suggest that as this reptile lost the ability to replace teeth, the likelihood of infections of the jaw, resulting from damage to the teeth, increased substantially. This is because prolonged exposure of the dental pulp cavity of heavily worn or damaged teeth to oral bacteria was much greater than in other animals that quickly replaced their teeth.

Reisz notes that human susceptibility to oral infection has some parallels to those of ancient reptiles that evolved to eat a diet incorporating plants in addition to meat. "Our findings suggest that our own human system of having just two sets of teeth, baby and permanent, although of obvious advantage because of its ability to chew and process many different types of food, is more susceptible to infection than that of our distant ancestors that had a continuous cycle of tooth replacement."


Contact: Nicolle Wahl
University of Toronto

Related biology news :

1. Mississauga teacher awarded prize for excellence in teaching genomics
2. Disrupting a destructive duo: U of T Mississauga researchers inhibit cancer proteins
3. Nationwide study finds US meat and poultry is widely contaminated
4. New study finds stronger regulations of in vitro fertilization may save lives
5. Study: Algae could replace 17 percent of US oil imports
6. Scots carbon emissions could be halved in decades, study suggests
7. Alcohol helps the brain remember, says new study
8. Study provides new way to classify E. coli bacteria and test for fecal contamination
9. UNC study helps clarify link between high-fat diet and type 2 diabetes
10. Clinical study suggests estrogen levels and breast health can be altered
11. New genetic study helps to solve Darwins mystery about the ancient evolution of flowering plants
Post Your Comments:
Related Image:
Reptilian root canal: U of T Mississauga study reveals infection in jaw of ancient fossil
(Date:11/19/2015)...  Based on its in-depth analysis of the biometric ... the 2015 Global Frost & Sullivan Award for Product ... this award to the company that has developed the ... the market it serves. The award recognizes the extent ... customer base demands, the overall impact it has in ...
(Date:11/17/2015)... Paris , qui ... Paris , qui s,est tenu du ... leader de l,innovation biométrique, a inventé le premier scanner ... sur la même surface de balayage. Jusqu,ici, deux scanners ... les empreintes digitales. Désormais, un seul scanner est en ...
(Date:11/12/2015)... , Nov. 12, 2015  Arxspan has ... of MIT and Harvard for use of its ... information management tools. The partnership will support the ... biological and chemical research information internally and with ... be used for managing the Institute,s electronic laboratory ...
Breaking Biology News(10 mins):
(Date:11/24/2015)...  Clintrax Global, Inc., a worldwide provider of clinical research services ... that the company has set a new quarterly earnings record in ... growth posted for Q3 of 2014 to Q3 of 2015.   ... , with the establishment of an Asia-Pacific ... United Kingdom and Mexico , ...
(Date:11/24/2015)... ... 24, 2015 , ... The Academy of Model Aeronautics (AMA), led by its ... as Multirotor Grand Prix, to represent the First–Person View (FPV) racing community. , FPV ... embraced this type of racing and several new model aviation pilots have joined the ...
(Date:11/24/2015)... 2015  Tikcro Technologies Ltd. (OTCQB: TIKRF) today announced that its Annual ... 11:00 a.m. Israel time, at the law offices ... Street, 36 th Floor, Tel Aviv, Israel . ... and Izhak Tamir to the Board of Directors; , ... , approval of an amendment to certain terms of options granted ...
(Date:11/24/2015)... ... November 24, 2015 , ... In ... paramount. Insertion points for in-line sensors can represent a weak spot where leaking ... 781/784 series of retractable sensor housings , which are designed to tolerate extreme ...
Breaking Biology Technology: