A study was made of three groups of materials used in dentistryq i. e. denture base acrylics, "Gel-type" tissue conditioners and epimine resins. Conventional denture base acrylic made by curing a dough of methyl methacrylate and poly(methyl methacrylate) beads is considerably weaker than homogeneous poly(methyl methacrylate). The reasons for this were revealed by a comparison of their fracture mechanics and morphology. Phase inhomogenuity was found in denture base acrylic, the interstitial phase having lower Mv and Young's modulus than the bead phase. A viscoelastic and autoradiographic study of the denture base acrylic revealed that the two phases were interpenetrating polymer networks. It was found possible to improve the strength of denture base acrylic by the addition of methacrylic acid thus improving the 19 v of the interstitial polymer. The combination of methacrylic acid and cross-linking agent also facilitated the control of phase stiffness. Improving the molecular weight and matching the phase stiffness produces a conventional denture base material of comparable strength to homogeneous poly(methyl methacrylate)o A study of the effects on "Gel-type" tissue conditioners of an oral environment revealed the reasons for their loss of compliance during clinical use. The alcohol desorption and water absorption characteristics of the gels were studied. prom such studies and a knowledge of their chemical composition conclusions were drawn regarding the best ccr. positions for tissue conditioner gels intended for long service in the mouth. Two epimine ccnpounds, an impression rubber and a temporary crown and bridge material were studied. Their physical properties and chemical composition were determined. A car. parison of known long term behaviour of analogous resins; canbined with the determined physical properties of the epimine resins studiedt revealed some of the clinical limitations of such systems.

An evolution in methods of identifying the causal mutations and candidate genes for Mendelian disorders has occurred recently. Though several studies have reported the causative mutations in non syndromic tooth agenesis, there are only two reports on autosomal recessive nonsyndromic tooth agenesis in consanguineous families. Since the consanguinity rate is high in tribal population of Saudi and Pakistan, this study identified consanguineous families in these populations to investigate the molecular basis of tooth agenesis. This study aimed to study the phenotype of familial tooth agenesis in Saudi and Pakistani families of consanguineous marriage, and to identify the causative mutations. A further aim was to investigate the influence of the agenesis gene on tooth size in one large Saudi family. Sixteen families with non-syndromic tooth agenesis, were clinically characterised for the pattern of inheritance, tooth agenesis severity and type of teeth affected. Genetic analysis including homozygosity mapping and exome sequencing was performed in eight families. Hand measurements of Saudi family tooth dimensions were made on dental study models. The most affected tooth type in studied families were the lower second premolar and upper lateral incisors. The homozygosity mapping approach failed to identify the regions of the diseased mutations in these families. The exome sequencing data revealed a heterozygous novel frameshift mutation in exon 2 of the MSX1 gene, c.750_751insACCGGCTGCC (p.A250fs) in one Saudi family and a homozygous novel mutation in exon 8 of the SMOC2 gene, c.681T>A (p.C227X), in the Pakistani family. It was found that there was a significant (p <.0.05) trend of reduction in the crown sizes both in the tooth agenesis group and their family members with no tooth agenesis compared to the control group. It is concluded that homozygosity mapping was not sensitive to identify the elusive tooth agenesis gene and whole exome sequencing technique is needed in future studies. The tooth measurement study indicates and confirms that crown size is closely related to tooth agensis.

Thesis (M.D.S.)--University of Adelaide, Dept. of Dentistry, 1991. / Typescript (Photocopy). Errata slip inserted. Includes bibliographical references (leaves 96-102).

Thesis (M.D.S.)--University of Adelaide, Dept. of Dentistry, 1999. / Bibliography: leaves 284-317.

Thesis (Ph. D.)--University of Sydney, 2002. / Includes list of published articles and presentations: leaves xxxii-xxxiii. Includes bibliographical references. Also available in print form.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains iii, 22 p. Includes abstract. Includes bibliographical references (p. 19-22).

Thesis (doctoral)--München, 1934.

Thesis (doctoral)--München, 1934.

Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains ii, 24 p. Includes abstract. Includes bibliographical references (p. 20-24).

(Thesis: M.A.) / In 2000, US Surgeon General David Satcher released a report on the severity of oral health disease in the high risk demographic. His grave report ushered in an era of oral health prevention programs utilizing a combination of education, mouth rinses, fluoride varnishes, dental sealants, and more invasive procedures. Given this wide range of acceptable treatment interventions available, the aim of this paper is to evaluate the effectiveness of certain treatments both by themselves and in tandem with one another on target high risk school age children. The first program we analyzed was a fluoride mouth rinse program based in North Carolina. While we found that although this program may have positive impacts on school age children in the future, it did not currently provide statistically significant benefits to these children. Access to Baby and Child Dentistry, a program in Washington State that used a multi-pronged prevention program involving education, fluoride varnishes, and glass ionomer sealants provided a much clearer benefit to reducing the overall dental caries experience in target school age children. Lastly, the ForsythKids Program, based in Massachusetts which utilized a comprehensive care model of caries prevention was shown to be effective in reducing the number of new caries in school age children. Their comprehensive care model consisted of providing the children with fluoride toothpaste, applying fluoride varnish, fitting glass ionomer sealants and temporary restorations. Armed with this information and based on a model involving four steps and two factors crucial in the successful implementation of an oral health prevention program, we hope to offer a foundation for future forays into both installing and maintaining an oral health prevention program.