What Can A New Zealand Reptile Tell Us About False Teeth?

Using a moving 3D computer model based on the skull and teeth of a New Zealand reptile called tuatara, a BBSRC-funded team from the University of Hull, University College London and the Hull York Medical School has revealed how damage to dental implants and jaw joints may be prevented by sophisticated interplay between our jaws, muscles and brain. This research will appear in a future edition of the Journal of Biomechanics.

The tuatara is a lizard-like reptile that has iconic status in its homeland of New Zealand because its ancestors were widespread at the time of the dinosaurs. Unlike mammals and crocodiles which have teeth held in sockets by a flexible ligament, tuatara have teeth that are fused to their jaw bone - they have no ligament, much like modern dental implants.

BBSRC postdoctoral fellow Dr Neil Curtis from the University of Hull said "Humans and many other animals prevent damage to their teeth and jaws when eating because the ligament that holds each tooth in place also feeds back to the brain to warn against biting too hard."

Dr Marc Jones from UCL, also a BBSRC postdoctoral fellow, added "In the sugar-rich western world many people end up losing their teeth and have to live with dentures or dental implants instead. They've also lost the periodontal ligament that would attach their teeth so we wanted to know how their brains can tell what's going on when they are eating."

The team has created a 3-D computer model of the skull of the tuatara to investigate the feedback that occurs between the jaw joints and muscles in a creature that lacks periodontal ligaments. "Tuataras live happily for over 60 years in the wild without replacing their teeth because they have the ability to unconsciously measure the forces in their jaw joint and adjust the strength of the jaw muscle contractions accordingly", said Dr Curtis.

Although this explains why tuatara and people with false teeth manage not to break their teeth and don't end up with jaw joint disorders, it is still clear that having a periodontal ligament is very useful, in particular for fine tuning chewing movements. This may explain why it has evolved independently in the ancestors of mammals, crocodiles, dinosaurs, and even some fish.

There is anecdotal evidence to suggest that people with implants and dentures may make food choices related to their lack of periodontal ligament. However, the tuatara pursues a broad diet on the islands where they live including beetles, spiders, snails, frogs and occasionally young seabirds.

Professor Douglas Kell, BBSRC Chief Executive said "To support the extension of health and wellbeing into old age, it is vital that we appreciate how we as human beings have developed our extraordinary ability to adapt to adverse situations. This work allows us to understand some of the complexities of the feedback and responses occurring in healthy human bodies and brains. It is impossible in evolution to predict future innovations such as dental implants and yet this research indicates a level of redundancy in our biology that opens opportunities to support long term health and wellbeing."

Source: Nancy Mendoza- Biotechnology and Biological Sciences Research Council

Who Hasn't Had Dental Cavities?

A research study has for the first time revealed data about dental cavities, periodontal disease, oral treatment needs, the use of dental prostheses and dental hygiene habits among the adult population in the Valencia region. The results show that 90% of people have cavities and 20-35% need prostheses.

"These data will make it possible to draw comparisons with other studies carried out in other autonomous regions and nationwide ones", José Manuel Almerich, co-author of the study and a scientist at the University of Valencia (UV), tells SINC.

The study, published in the journal Medicina Oral, Patología Oral y Cirugía Bucal, for the first time provides data about the situation with regard to cavities, periodontal disease, oral treatment requirements and the use of dental prostheses in two age cohorts (35-44 and 65-74) in the adult population of Valencia. The study also includes an analysis of these people's oral hygiene habits.

The prevalence of cavities was above 90% in the two samples studies. Social class and educational levels have an impact on the presence of cavities, with those with lower social and education levels having more cavities. Nationality also has an impact, with foreigners having more untreated cavities.

Among the people aged 65 to 74, 20.7% are 'totally toothless'. "From these data we can deduce that the dental status of the institutionalized geriatric population is significantly worse than that of elderly adults living in their homes", says Almerich.

In terms of periodontal disease, the second most prevalent problem, the most disadvantaged social classes again present the worst health status, while the need for dental prostheses fluctuates between 20-35% for the entire population studied, increasing in the older age group.

Bad habits starting in childhood

The study confirms our poor dental hygiene habits and rare visits to the dentist. "Preventive efforts should be aimed at raising awareness about the need for early diagnosis of problems and the best possible oral hygiene", the Valencian researcher suggests.

The findings of this study underline the need to improve dental care among adults. The authors highlight the need to develop new policies that will improve prevention as well as dental care measures "that will make it possible to improve the bucodental map within a few years".

Source: Plataforma SINC 

Want To Be Sexy? Improve Your Oral Hygiene

If you're thinking about being romantic tonight, you might want to make sure your oral hygiene is in check. Based on a new survey, oral hygiene is significantly preferred over the traditional romantic overtures to set the mood, such as dimming the lights, lighting candles, wearing perfume or playing romantic music.

"The results of this study reinforced some of what we already knew - that most consumers simply don't like to floss with string - but we were surprised at how important oral hygiene was in order to be attractive to your significant other"

The national survey, which was fielded by Kelton Research, examined Americans' views on oral healthcare and revealed that a clean mouth was most important in maintaining a healthy relationship. Close to six in ten, or 59 percent, would be most disturbed by their partner not brushing or flossing his or her teeth for a week, as compared to only 24 percent who would be most perturbed if their significant other passed on wearing deodorant. Far fewer were bothered by their partner skipping shaving, hair combing or trimming toe nails for a week, at nine percent, six percent and two percent, respectively.

The Waterpik® Sexy Smile Survey also found that while they are quick to judge the flossing habits of their significant others, the majority of Americans actually have a lot of ups and downs in their own relationship with floss. Key findings on flossing and oral healthcare include:

- Only When I'm Desperate. Americans are most likely to floss just before visiting the dentist (51 percent), and when they have food stuck in between their teeth or have bad breath (64 percent), which could mean their mouths are not as fresh as they should be most other times!

- Below Grade. Nearly six in ten (58 percent) Americans say they deserve a C or lower for the efforts they make to floss their teeth on a daily basis. In fact, about one in five (18 percent) give themselves a failing grade.

- Unpleasant Act. Among people who floss their teeth, close to six in ten (57 percent) say that floss makes their gums bleed, it gets stuck between their teeth, (52 percent), and it caused little bits of food to fly onto the mirror (42 percent). Yuck!

- We Want an Alternative. In fact, Americans would pay an average of $53 for an alternative to regular string floss (which you can usually get for free from your dentist) if it meant that the process was faster, easier and more effective.

"The results of this study reinforced some of what we already knew - that most consumers simply don't like to floss with string - but we were surprised at how important oral hygiene was in order to be attractive to your significant other," said Jay McCulloch, Vice President of Marketing for Water Pik Oral Health Products.

About The Water Survey

The Waterpik® Sexy Smile Survey was conducted by Kelton Research between September 10 and September 16, 2010 among 1,001 U.S. adults using an email invitation and an online survey. Quotas are set to ensure reliable and accurate representation of the total U.S. population ages 18 and over. Results of any sample are subject to sampling variation. The magnitude of the variation is measurable and is affected by the number of interviews and the level of the percentages expressing the results. In this particular study, the chances are 95 in 100 that a survey result does not vary, plus or minus, by more than 3.1 percentage points from the result that would be obtained if interviews had been conducted with all persons in the universe represented by the sample.

Source: Kelton Research- Water Pik, Inc.