Identification Of Porphyromonas Gingivalis Genes Required For Iron/haem Acquisition And Biofilm Formation
Funder
National Health and Medical Research Council
Funding Amount
$476,836.00
Summary
Periodontal diseases are some of the most common bacterial diseases of humans and along with dental caries, account for approximately 90% of all tooth loss in the Australian population. A recent survey of oral health in Australia found that in the 30-34 age group over 20% of people had moderate to severe periodontal disease, indicating that periodontitis is a major public health problem. Specific bacteria, especially Porphyromonas gingivalis, that grow as bacterial biofilms (dental plaque) cause ....Periodontal diseases are some of the most common bacterial diseases of humans and along with dental caries, account for approximately 90% of all tooth loss in the Australian population. A recent survey of oral health in Australia found that in the 30-34 age group over 20% of people had moderate to severe periodontal disease, indicating that periodontitis is a major public health problem. Specific bacteria, especially Porphyromonas gingivalis, that grow as bacterial biofilms (dental plaque) cause periodontal disease. In this study we will utilise the latest technology available to determine which genes of the bacterium are important for biofilm growth, iron acquisition and virulence in an animal model. We will investigate how the bacterium acquires iron, as there is usually little available iron for bacterial growth on human tissues and the ability of the bacterium to free itself from this iron limitation is associated with pathogenicity. The determination of the role of iron availability in biofilm formation and virulence of the bacterium will help us to understand the changes that occur in the initiation of disease and may allow the development of early intervention strategies. The significance of this work is that we will gain an understanding of how this bacterium functions as an opportunistic human pathogen. We will determine which genes are essential for growth as a biofilm and to produce disease in an animal model. This will enable the development of therapeutic and prophylactic interventions targeted to specific bacterial gene products required to produce disease.Read moreRead less
The Impact Of Declining Tooth Loss On Oral Health Status And Dental Care Utilisation
Funder
National Health and Medical Research Council
Funding Amount
$144,375.00
Summary
Improved oral health has been well documented in Australia. Over recent decades the average number of decayed teeth among children has decreased. Among adults, the percentage with no natural teeth has also exhibited a decrease over time. While increased retention of natural teeth is an indicator of improved oral health status within the population, there may be some unexpected consequences of this success. Improved oral health has been associated with increased rather then decreased use of servi ....Improved oral health has been well documented in Australia. Over recent decades the average number of decayed teeth among children has decreased. Among adults, the percentage with no natural teeth has also exhibited a decrease over time. While increased retention of natural teeth is an indicator of improved oral health status within the population, there may be some unexpected consequences of this success. Improved oral health has been associated with increased rather then decreased use of services. Improvements in oral health manifested in the form of greater tooth retention, coupled with demographic trends towards growth in the population, may lead to an increased risk of oral disease with flow on effects on need and demand for care. Findings from one cross-sectional study in the USA have shown that people who retained higher numbers of teeth had more periodontal disease and dental caries experience, and reported a past pattern of visiting the dentist more frequently. The specific aims of this project are to examine the association of the number of natural teeth among middle-aged Australians with their oral health status, treatment needs and subsequent use of dental services. The outcome of this project will provide answers to two research questions. Firstly, it will see whether the retention of more teeth among adults is associated with higher levels of oral disease. Secondly, by following people over time it will be able to detect whether those who are retaining more teeth into adult age ranges have higher levels of use of dental services than their counterparts with fewer teeth. The answers to both of these research questions has significance for policy and planning in the area of dental public health by providing evidence as to the size and direction of expected future demand for and use of dental services in Australia.Read moreRead less
Control Of Mastication By Periodontal Mechanoreceptors In Man
Funder
National Health and Medical Research Council
Funding Amount
$169,990.00
Summary
Despite the importance in chewing and speech, very little is known regarding the fine control of jaw muscles. A thorough understanding of the control of the jaw muscles is at the base of improved diagnosis and treatment of many chewing disorders. For example: We still do not understand the causes of the jaw muscle-joint pain disorder (temporomandibular dysfunction) which accounts for about 5 % of total dental patients. The current treatments, including pain killers, night plates and massage cure ....Despite the importance in chewing and speech, very little is known regarding the fine control of jaw muscles. A thorough understanding of the control of the jaw muscles is at the base of improved diagnosis and treatment of many chewing disorders. For example: We still do not understand the causes of the jaw muscle-joint pain disorder (temporomandibular dysfunction) which accounts for about 5 % of total dental patients. The current treatments, including pain killers, night plates and massage cure only about half of all patients. Improved diagnosis and treatment techniques require more precise elaboration of the neural and muscular mechanisms of chewing. Why do the chewing forces in toothless individuals, despite well fitting dentures, fall to about 20 % of the value in teethed individuals? Do jaw muscles in these subjects weaken because they get less feedback from the receptors around the teeth? How does the chewing force automatically adjust to overcome sudden or gradual changes in the characteristics of foodstuff? Although bite to bite changes in the chewing force is observed in subjects with natural teeth, no such changes occur in toothless subjects or subjects chewing with implanted bridges. How do the receptors adjust the activation of jaw muscles so that bite force is applied in the right direction and right amount at each bite? The aim of this study is to define the importance of the periodontal mechanoreceptors (tiny nerve cells that are situated between the roots of the teeth and the jaw bone that signal bite force to the brain) in the control of jaw muscles. This study will, therefore, illustrate the importance of keeping the teeth and gums healthy for the development of strong, smooth and well-controlled chewing forces, and potentially create opportunities to improve chewing (and thereby quality of life) in toothless individuals or those experiencing other difficulties in chewing.Read moreRead less
Effect Of Prostaglandin E2 On The Periodontium And Alveolar Bone Formation
Funder
National Health and Medical Research Council
Funding Amount
$211,527.00
Summary
Dental disease affecting the supporting structures of teeth (the periodontium), is prevalent in our society. Periodontal disease results in destruction of bone around teeth, loosening of teeth, compromised chewing function, and tooth loss. Over the last twenty years reports into the effects of prostaglandin E2 (PGE2) on the skeleton have been divided and controversial. While historically PGE2 has been reported to promote bone resorption, more recently it has been demonstrated that when PGE is pl ....Dental disease affecting the supporting structures of teeth (the periodontium), is prevalent in our society. Periodontal disease results in destruction of bone around teeth, loosening of teeth, compromised chewing function, and tooth loss. Over the last twenty years reports into the effects of prostaglandin E2 (PGE2) on the skeleton have been divided and controversial. While historically PGE2 has been reported to promote bone resorption, more recently it has been demonstrated that when PGE is placed in contact with mandibular bone, adjacent to erupted teeth, new bone and cementum formation occurs. The ability of PGE2 to induce new bone formation indicates a potential use for PGE2 in the management of bone loss associated with periodontal diseases, and the formation of new bone around dental implants, and around teeth following orthodontic movement. Growth factors are active in healing and have valuable applications in augmenting wound repair. Osseous and dental tissues are rich in growth factors, and these factors are involved with the regulation of bone metabolism as well as tissue repair, thus the action of PGE2 on the periodontium is most likely regulated via these factors. Since regeneration of the periodontium is a fundamental goal of dentistry, any treatment which leads to predictable formation of new connective tissues and their long term stability would be a major clinical advance.Read moreRead less