Date: January 31, 2013 (Thursday)
Time: 12:45 p.m. to 1:45 p.m.
Venue: Lecture Theatre II, G/F, The Prince Philip Dental Hospital
Presenter: Miss Tian Tian, PhD Candidate (12:45 p.m. to 1:15 p.m.)
Title: Aspects of bonding between resin luting cements and glass ceramic materials
Abstract: Glass ceramics are widely used in dental restorations because of their excellent esthetic performance. Nowadays, there are increasing cases where the retention of restorations is reliant on bonding. Hence, the quality of bonding is of increasing importance, and is a dominant factor required for the long-term success of glass ceramic restorations. It is accepted that adhesion between ceramics and resin cements is provided by two major mechanisms: micromechanical attachment and chemical bonding. However, no wide agreement has been reached for optimal bonding. Furthermore, the ceramic and resin cement bond is subjected to a complex environment in the oral cavity being influenced by several extrinsic factors. Consequently, laboratory testing should simulate these variables to enable the development of superior materials and surface preparation methods that provide long-term durable bond strengths in the oral environment.
The aim of this study is to analyze laboratory studies investigating the resin cement bond to glass ceramics, to compare two bonding models using a microtensile bond strength test and to evaluate the effect of surface treatments on resin ceramic bonding as well as to evaluate the influence of different storage media on the ceramic/resin bond.
Presenter: Mr. Liu Quan, PhD Candidate (1:15 p.m. to 1:45 p.m.)
Title: Studies on bone minerals: micro/nano-structural and compositional investigations, assessments and simulations
Abstract: Skeleton is of great importance to vertebrates since bones are responsible for the supporting and moving of animal body, mineral storage as well as hematopoiesis. Biological apatite is the main inorganic component of biological hard tissue, including human bones and teeth. Because of such a similarity, animal bone-derived grafting materials have been used for bone reconstruction in dentistry and medicine. Given the clinical value of biological apatite, numerous studies about its basic knowledge and clinical performance have been done. However, some gaps, limitations and problems about the morphology, crystal size, solubility and biodegradation of biological apatite still remain. Hence, this study is to investigate the micro/nano-structure and chemical compositions of series of vertebrate bones; to assess the physiochemical properties of biological apatite; and to examine the effect of various ions to the solubility of biological apatite by taking hydroxyapatite as a simulative model, aiming at obtaining a comprehensive understanding of the physiochemical properties of bone minerals.