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Background or statement of the problem. Acrylic polymers, such as polymethyl methacrylate (PMMA), are widely used in the fabrication of removable dental prostheses due to their numerous advantages. These include adequate physical, mechanical, and aesthetic properties, low cost, easy fabrication, and biocompatibility. However, the lack of antimicrobial effects in denture base resins (DBRs) has garnered significant interest among dental researchers, particularly because PMMA lacks the ability to resist antimicrobial activity. Specifically, a recurring oral condition such as Candida-associated denture stomatitis (CADS) is difficult to eliminate because disease-causing yeast bacteria or fungi can penetrate the denture base materials. Furthermore, three-dimensional (3D) printing is rapidly emerging at the forefront of digital technology and permeating the dental profession, expanding treatment options for patients, such as fabricating dental prostheses. However, the surface properties of 3D printed materials have posed challenges in both general medicine and dentistry, primarily due to the potential for microbial adhesion to the material surface. To address this issue and mitigate the formation of biofilms on denture surfaces, previous studies have explored the incorporation of organic or inorganic antibacterial and antifungal agents into DBRs. Building upon this body of research, this study utilised phytochemical substances such as microencapsulated plant essential oils in 3D printing denture base materials. Objectives. The objectives of this project were: i. to incorporate microcapsules, containing biodegradable essential oil, into two 3D printed DBRs and investigate their effects on the physical and mechanical properties of the materials to ISO standards, ii. investigate the antimicrobial activity of the resulting materials, and to iii. investigate the cytotoxicity of the microcapsules. [...], Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Medicine & Dentistry, Griffith Health, Full Text

The development of bioactive materials that can mimic bone tissue has been an area of active research to try and improve the process of implant integration. Wool-derived keratin, a readily available natural polymer, has been shown in vivo to enhance bone healing and as such may be a novel material for use in the development of biomimetic devices. Coating titanium with keratin, therefore, may be a promising approach to achieve this, but effective bonding between keratin and titanium and the molecular response of osteoblasts to keratin has not been fully delineated. Using aminosilane (APTES) and glutaraldehyde (GA) to prepare the titanium surface, two coating strategies were employed in the present study i.e., solvent casting and molecular grafting, to try and improve the coating's chemical and mechanical properties and improve the interaction between keratin and adherent osteoblastic cells. This thesis had three main goals. First, to characterize the physiochemical and mechanical properties of the keratin coating using various analytical techniques. Second, to evaluate the cytocompatibility of the keratin coating with osteoblastic MG-63 cells in vitro. Finally, to investigate the bone healing response to keratin-coated titanium in vivo using a rat calvarial defect model. [...], Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Medicine & Dentistry, Griffith Health, Full Text

Aims: The present thesis aimed to study the interplay between periodontal disease and inflammatory bowel disease using a model where both diseases could co-exist in the same animal. Our specific aims were: 1) systematically review (SR) studies that evaluated the immunological traits of patients with both Inflammatory bowel disease (IBD) and periodontal disease; 2) investigate the impact of dextran sulphate sodium (DSS)-induced colitis (DIC) on histopathological and immunological outcomes in the periodontal tissues of Wistar rats; 3) investigate whether ligature-induced periodontitis (LIP) could affect the expression of Th1/Th2-related cytokines in the colon of Wistar rats; and 4) investigate the impact of non-surgical periodontal treatment (NSPT) on the expression of cytokines and chemokines in the intestine and gingival tissues of Wistar rats with DIC and LIP. [...], Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Medicine & Dentistry, Griffith Health, Full Text

Full Text, Thesis (Masters), Master of Medical Research (MMedRes), School of Pharmacy & Med Sci, Griffith Health, Bisphosphonates are a group of drugs widely used in medical practice to prevent bone destruction, occurring in diseases like osteoporosis and bone cancer. An unfortunate sideeffect of these potent drugs is the subsequent death of areas of bone in the jaw following minor local trauma, commonly occurring during dental treatment. This unique, but welldocumented, adverse effect is termed medication-related osteonecrosis of the jaws (MRONJ). While the precise cause of MRONJ is still unclear, research suggests the inhibition of new blood vessel formation, limiting the capacity for bone healing, may be a significant factor. Unfortunately, treatment options for MRONJ are very limited, and despite successful development of bone mimetic materials, most available materials do not induce sufficient formation of blood vessels. Adequate vascularisation is crucial for timely and adequate transport of nutrients and waste removal, and the provision of progenitor cells for tissue remodeling and repair. This study provides a rationale for a new innovative approach using a human-adipose derived microvessel (HAMV)-osteoblast construct, which will potentially support local bone regeneration and healing. This project takes the important first steps in vitro, investigating the growth, migration, and viability of the HAMV within a 3D hydrogel construct and assessing the influence of HAMV development on osteogenesis, in order to provide the data necessary for subsequent testing in a pre-clinical animal model. In this study, HAMV were seeded into tissue culture plates and cultured over 28 days, to evaluate the proliferation potential of the HAMV in a 3-dimensional (3D) collagen hydrogel construct. Growth, proliferation and morphological changes, including cell death, of HAMV were also visualised and were examined via LIVE/DEAD® assay with the aid of confocal microscopy. The human osteoblast cell line, MG63, was cultured in conditioned media derived from the HAMV cultures to understand the inf

Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Dentistry&Oral Hlth, Griffith Health, Biomaterial scaffolds engineered to facilitate osteogenesis which can subsequently remodel in a similar fashion to that of natural tissue, is an ideal clinical strategy for treating bone defects in the maxillofacial region. This study has developed, using a novel melt electrowriting (MEW) technique, various graded porous polycaprolactone (PCL) scaffolds able to imitate the bimodal structure of cortical and cancellous bone tissue in terms of their morphological pore structure. These scaffolds were subsequently shown to facilitate the proliferation of osteoblasts with significant alkaline phosphatase (ALP) activity. Scaffolds with a staggered architecture i.e. those where the corresponding fibers in different layers are offset horizontally during the printing process, increases the number of contact points, enables larger pores, facilitates cell attachment and creates a highly porous structure with interconnected networks favourable for improved cell migration and vascularization. MEW is a relatively new technology that fills a gap between conventional fused deposition modelling (FDM) 3D printing and solution electrospinning by affording significantly better control over the fabrication of the porosity in scaffolds. This is due to the high-resolution during printing of the fibers which enables small pore sizes in the desired porosity. PCL polymer with its advantages of less immunoreactivity following implantation and mechanically suitability for the support of bone cells, has flexibility in design and is widely used in bone applications. However poor bioactivity and cellular affinity as well as long-term degradation issues with PCL have been reported. A promising solution to overcome these drawbacks is fiber surface modification such as coating with bioactive inorganic components. hydroxyapatite (HAP) is the most stable form of calcium phosphate (CaP) used to improve the hydrophobic characteristics of PCL and enhance the binding affinity to the host tissue and promote

Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Dentistry&Oral Hlth, Griffith Health, Students in diverse health programs taught separately from each other with a focus on profession ‘specific’ content rather than comprehensive collaborative patient care promotes a limited understanding of and respect for the collaborative role of different health professionals when undertaking treatment planning and patient-centred care. This may result in oral health graduates educated within a uniprofessional context becoming ill-prepared to manage patients with complex conditions that require collaboration with different oral health professionals (OHPs) through a team-based patient-centred approach. As the potential value of interprofessional education (IPE) is strongly advocated in the literature, the Griffith University School of Dentistry and Oral Health (DOH) introduced the interprofessional teams-based treatment planning (TBTP) process in 2009 to address these educational challenges and facilitate IPE. The TBTP process incorporated student practice teams and an expansion of peer learning through collaboration between students enrolled in three different oral health programs, namely dentistry, dental technology and oral health therapy. It was perceived that shared learning, understanding of complementary knowledge, collaborative participation in managing patient care, and having knowledge/respect for each professions’ role were all necessary to improve communication and teamwork skills in a pre-qualification context in readiness for collaborative oral health practice. However, a systematic evaluation of the TBTP process, its contribution to student clinical learning and experiences, and whether those experiences contributed to advancing interprofessional competencies and capabilities at DOH has not been conducted since its commencement. This thesis documents an evaluation that researched the attitudes, perceptions and experiences of students, clinical teaching staff, patients and newly graduated OHPs involved with the TBTP process at DOH between 2012 and 2015