Dentistry Commons^™

Antimicrobial Peptide Coating Of Dental Implants: Biocompatibility Assessment Of Recombinant Human Beta Defensin-2 For Human Cells, Patrick Warnke, Eske Voss, Paul Russo, Sebastien Stephens, Michael Kleine, Hendrik Terheyden, Qin Liu

Qin Liu

Purpose: Artificial materials such as dental implants are at risk of bacterial contamination in the oral cavity. Human beta defensins (HBDs), small cationic antimicrobial peptides that exert a broad-spectrum antibacterial function at epithelial surfaces and within some mesenchymal tissues, could probably help to reduce such contamination. HBDs also have protective immunomodulatory effects and have been reported to promote bone remodeling. The aim of this study, therefore, was to investigate the influence of recombinant HBD-2 on the proliferation and survival of cells in culture.

Materials and Methods: Human mesenchymal stem cells (hMSCs), human osteoblasts, human keratinocytes (control), and the HeLa cancer …

Glass-Ceramics For Non-Metallic Dental Implant Applications, Selma Saadaldin

Electronic Thesis and Dissertation Repository

Metallic dental implants are an important treatment for the replacement of missing teeth. However, for esthetic and environmental issues, there is a need to develop non-metallic dental implant materials. In this thesis, two novel glass-ceramics (GCs), miserite and wollastonite, were synthesized for one-piece dental implant applications. Glasses were synthesized by wet chemical methods, followed by calcination, melting and quenching. The crystallization kinetics of these glasses were determined by differential thermal analysis (DTA). GC specimens were produced by cold pressing of the glass powder and sintering using schedules determined by DTA. The crystalline phases and microstructure of the GC samples were …

Comparing Velscope Vx And Traditional Oral Exams In Shisha (Hookah) Smokers: A Pilot Study, Amanda E. Kimball

Dental Hygiene Theses & Dissertations

The purpose of this study was to compare oral findings using two exam types, the VELscope Vx® screening device versus a modified oral examination in detecting oral potentially malignant lesions in shisha smokers.

Methods: Thirty-one participants who reported currently smoking shisha and tobacco were recruited. Participants were identified for smoking habits to include two groups, to include those who reported smoking shisha exclusively and those who reported smoking shisha and tobacco. Each group received both exam types; examiners used a standardized protocol. A health history questionnaire was also collected to assess participant's oral cancer risk factors such as age, race, …

Protaper Rotary Instrument Fracture During Root Canal Preparation: A Comparison Between Rotary And Hybrid Techniques, Huma Farid, Farhan Raza Khan, Munawar Rahman

Section of Dental-Oral Maxillofacial Surgery

AIMS:

This study aimed to compare the frequency of ProTaper rotary instrument fracture with rotary (conventional) and hybrid (rotary and hand files) canal preparation techniques. Secondary objectives were to determine whether there was an association of ProTaper file fracture with the canal curvature and to compare the mean time required for canal preparation in the two techniques.

METHODS:

An in vitro experiment was conducted on 216 buccal canals of extracted maxillary and mandibular first molars. After creating an access cavity and a glide path for each canal, a periapical radiograph was taken and the canal curvature was measured with Schneider's …

Advantage Of Combined Amalgam-Composite Restoration: In Vitro Leakage Study, Ahmed A. Madfa

Ahmed A. Madfa

Purpose: Evalute the leakage of Class II box composite restorations and compared with composite lined by flowable composite and combined amalgam-composite restoration. Method: Fifty-four Class II box shaped cavities were on the distal (1 mm below CEJ) surfaces, 18 cavities for each. Scotchbond Multi-Purpose adhesive system, Filtek Z250 composite, and a metal band system were used for all. After thermocycling test (1000 cycles, 5–55°C with 30 s) and dye immersion, the teeth were sectioned longitudinally in a mesio-distal direction and dye penetration was recorded. Results: Combine amalgam-composite restorations showed less gingival leakage than composite alone and composite lined by flowable …

Application Of Calcium Phosphate Materials In Dentistry, Ahmed A. Madfa

Ahmed A. Madfa

Calcium phosphate materials are similar to bone in composition and in having bioactive and osteoconductive properties. Calcium phosphate materials in different forms, as cements, composites, and coatings, are used in many medical and dental applications. This paper reviews the applications of these materials in dentistry. It presents a brief history, dental applications, and methods for improving their mechanical properties. Notable research is highlighted regarding (1) application of calcium phosphate into various fields in dentistry; (2) improving mechanical properties of calcium phosphate; (3) biomimetic process and functionally graded materials. This paper deals with most common types of the calcium phosphate materials …

Micromechanical Analysis Of Nanoparticle-Reinforced Dental Composites, Yi Hua, Linxia Gu, Hidehiko Watanabe

Department of Mechanical and Materials Engineering: Faculty Publications

The mechanical behavior of TiO₂ nanoparticle-reinforced resin-based dental composites was characterized in this work using a three-dimensional nanoscale representative volume element. The impacts of nanoparticle volume fraction, aspect ratio, stiffness, and interphase zone between the resin matrix and nanoparticle on the bulk properties of the composite were characterized. Results clearly demonstrated the mechanical advantage of nanocomposites in comparison to microfiber-reinforced composites. The bulk response of the nanocomposite could be further enhanced with the increased nanoparticle volume fraction, or aspect ratio, while the influence of nanoparticle stiffness was minimal. The effective Young’s modulus and yield strength of the composite was …

Characterising The Deformation Behaviour Of Human Tooth Enamel At The Microscale, Simona O'Brien

Theses: Doctorates and Masters

Enamel plays an important role in tooth function. Optimal combinations of composition and structure endow enamel with unique mechanical properties that remain largely unexplored. Specifically, more detailed understanding of the loadbearing ability of enamel is needed to mimic it synthetically and to design next generation biocomposite materials. This research investigates the variables that influence deformation behaviour of tooth enamel in relation to its hierarchical structure. Initially, a new method was developed for preparing flat, finely polished tooth samples that were maintained in their normal hydrated state for nanoindentation testing. In contrast to conventional methods, which commonly utilise either inappropriate or …