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Background: A phase-down of amalgam in Australia is possible given the Australian Government intends to ratify the Minamata Convention. There is little research as to the influence of a dentist's knowledge on decision-making, which may be of use when determining the impact of any change.Methods: An online survey relating to aspects of and attitudes to use of direct restorative materials was distributed to all dentists who were members of the Australian Dental Association or Members or Fellows of the Royal Australasian College of Dental Surgeons.Results: There were 408 respondents. Fifty-eight per cent agreed that there was consistency in undergraduate teaching. Fifty-two per cent stated that there was a difference between undergraduate teaching and the 'real world'. Postgraduate education was ranked the most important influence on decision-making. Ninety-six per cent stated that knowledge of the evidence base is important and 89% believed that they practised evidence-based dentistry.Conclusions: Dental schools need to maintain teachers' and students' understanding of the evolving technology of direct restorative materials. There is a perceived disconnect between undergraduate teaching and the 'real' world. The evidence base is viewed as confusing, contradictory and not readily understandable. The creation of clinical guidelines would be useful. [ABSTRACT FROM AUTHOR]

Background: The Minamata Convention embodies a worldwide reduction in the production and use of mercury and mercury-containing products and processes, including a phase-down of dental amalgam. This will change the approach to the use of direct restorative materials in the near future. There is little research as to the influence of clinical factors on dentists' decision-making which may be of use when determining the impact of any change.Methods: An online survey relating to aspects of and attitudes to the use of direct restorative materials was distributed to all dentists who were members of the Australian Dental Association and/or members or fellows of the Royal Australasian College of Dental Surgeons. Data were statistically analysed.Results: There were 408 respondents to the survey. Eighty-seven per cent of respondents (strongly) disagreed that amalgam was a technically more difficult material to place compared with resin composite, 82% (strongly) disagreed that placement time for amalgam was longer than that for resin composite and 69% (strongly) disagreed that amalgam was more difficult to finish than resin composite. Eighty-three per cent of respondents stated they were confident in their ability to place amalgam restorations. Where physical properties were of importance, indirect restorations were preferred (e.g. parafunction) 54%. The factors considered most important when choosing a direct restorative material included moisture control and aesthetics; least important factors were cost and time to place.Conclusions: There is consensus that amalgam is not more technically difficult to use, place or finish than resin composite and vice versa. There is recognition that both amalgam and resin composite have limitations in terms of physical properties. When choosing a direct restorative material, clinical factors considered to be of greatest importance are moisture control, aesthetics and the need to apply minimally invasive approaches. There is little difference in the opinions of users and non-users of amalgam with respect to these findings. [ABSTRACT FROM AUTHOR]

Background: The clinical technique for sandwich restorations prescribes etching initially set auto cure glass ionomer cement (GIC) prior to placing a layer of resin bond to develop a weak mechanical bond between composite resin and GIC. Co-curing a resin modified glass ionomer cement (RMGIC) bond and composite resin to GIC may create a chemical bond and improve the bond strengths between these two materials. Methods: A total of 48 specimens were prepared, 12 in each of four categories. Capsulated GIC was placed into a mould and allowed to set for four minutes, etched for five seconds followed by placement of a resin bond and photo cured for five seconds over which a composite resin was puddled onto the resin bond and photo cured for 10 seconds. Capsulated GIC was placed into a mould and allowed to set for four minutes after which a sample of RMGIC (Riva LC) was prepared using twice the liquid powder ratio and painted over the surface of the set GIC using a micro brush. An increment of composite resin was added over the RMGIC and both materials were photo co-cured for 10 seconds. Capsulated GIC was placed into a mould and RMGIC (Riva LC) that had been prepared using twice the liquid powder was brushed over the GIC (prior to initial set) followed by the placement of a layer of composite resin and photo co-cured for 10 seconds. Capsulated GIC was placed into a mould and RMGIC (Fuji II LC) that had been prepared using twice the liquid powder was brushed over the GIC (prior to initial set) followed by the placement of a layer of composite resin and photo co-cured for 10 seconds. Shear testing of each of the samples was carried out and specimens were examined to determine the nature of the fracture. Selected samples were prepared for SEM investigation to observe the interfaces between the GIC and composite resin. Results: There were significantly lower bond strengths (P<0.05) amongst samples that had been etcp606202p60hed and bonded (2.42MPa) compared to the other samples that had been co-cure bonded with RMGIC (6.48–7.05MPa). There were no significant differences amongst the bond strengths of the samples co-cure bonded with RMGIC. Specimens prepared by the ‘etch and bond’ technique failed adhesively and co-cured specimens failed cohesively within the GIC. SEM investigation showed chemical bonds between RMGIC bond and GIC and composite resin. Conclusions: The co-cured RMGIC bonding system eliminates several placement steps and produces a significantly stronger chemical bond between GIC and composite resin than the ‘etch and bond’ technique. RMGIC bond and composite resin may be co-cured to GIC either before or after initial set has occurred. [ABSTRACT FROM AUTHOR]

Objectives: To review governmental guidelines on amalgam use worldwide and to assess trends in the usage of amalgam and composite materials in restoration of posterior teeth. Methods: A letter was sent to 24 government health agencies or representative organisations requesting details of regulations pertaining to amalgam use. A literature search was carried out in order to identify papers in which the incidence of amalgam and composite restorations was stated. Results: Ten replies were received, indicating few restrictions on the use of amalgam. Results obtained from published work appear to indicate that amalgam use is declining, but at rates which are unclear in many countries because of the paucity of published data. Amalgam use has been found to be decreasing in the USA, Australia and Scandinavia, with lesser decreases being apparent in the UK. Conclusions: There are few restrictions to the use of amalgam worldwide. In countries where data are available, such as USA, Australia and Scandinavia, amalgam use has been found to be decreasing, with smaller decreases being apparent in the UK. [ABSTRACT FROM AUTHOR]