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The shear bond strength of three adhesives, Panavia 21, Superbond, All Bond CB Cement, and a dual cure resin (Variolink), to Ni-Cr-Be (Rexillium III), Midigold (Type III gold) and Amalgam (Sybraloy) were determined. Fifteen samples were prepared using 800 grit abrasive papers for Ni-Cr and Midi-Gold, and 100 grit papers for amalgam. Ni-Cr-Be and Midi-Gold samples were sandblasted for 30 s and steam cleaned for 10 s. The adhesives were bonded to the samples using gelatine capsules and were matured for 24 h in water at 37 degrees C. The samples were debonded in shear using an Instron at a cross-head speed of 1 mm/min. The data was analysed using ANOVA and a Tukey test. The bond strength of Superbond to both metal alloys was significantly higher (P0.05) than any of the materials tested, with the exception Panavia 21 to gold. The bond strength of All Bond CB cement had shown to be not significant difference from those of Panavia 21 and Variolink, when bonded to Rexillium and Midi-Gold, respectively. The bond strength of All Bond CB Cement to amalgam was significantly greater (P0.05) than those of the other materials tested. The shear bond strength to gold showed lower bonding for all adhesives when compared with Rexillium (P.001). The ranking of bond strength to both alloys was as follows: SuperbondPanavia 21All Bond CBVariolink. The nature of substrate to be used for bonding and the adhesive material itself are important factors in bonding which can be achieved between cast metals and prepared teeth with amalgam filling. Superbond should be successful as an adhesive for the attachment of all substrates tested, with the possible exception of amalgam, for which All Bond CB Cement gives the best result.

The Swiss Health Surveys are conducted every 5 yr, and alternate surveys contain information on oral health. Worldwide the population is ageing and oral health is improving. The aim of this study was to identify if these trends are continuing in a relatively affluent society with low levels of edentulousness. Participants in the 1992 and 2002 surveys completed a written questionnaire including items on oral health (response rates 75% and 86% respectively). Data were weighted and bivariate analyses were performed to calculate the average number of missing teeth and the prevalence of different prosthetic dental restorations for each cohort. Over the 10-yr period the proportion of subjects retaining all natural teeth increased, and the mean number of teeth increased, on average, by 1.3. Among those who required prosthetic dental restorations, fixed restorations increased and complete denture use was reduced. Strikingly, 4.4% of this sample reported having oral implants in 2002. Greater numbers of missing teeth and a higher prevalence of use of removable prostheses were still seen in women, in those who had only completed compulsory education, in subjects from families with low income, in those who smoke, and in those who were overweight, in 2002.

The aim of this study was to investigate the impact of both population age changes and falling edentulism rate on the denture market in three European countries.Detailed information on the rate of edentulism for only three European countries (Finland, Sweden, and the UK) was available. For the UK and Sweden, published predicted rates of edentulism for the future decades were used, whereas predictions for Finland were computed using published edentulism rates. Edentulousness in one jaw was also predicted and included in the computation. Demographic projections were taken from government agency websites.The denture market will decrease in the three countries. Sweden, where edentulism is already low, will experience the largest percentage decrease (60%) over 20 years, but, in absolute number, the change will be of smaller magnitude than that in the UK and Finland. The range of projections for Finland was large, reflecting the difficulty of predicting trends with incomplete information. Within the limitations of this study's design, the impact of population age changes will not increase the denture market in Europe, even with the most pessimistic projections for edentulism rate.The complete denture market in Europe will fall despite changing age demographics. The falling rates are large enough to markedly affect future patterns of treatment provision and training.

In this study, the penetration of three proprietary dentine-bonding agents (PrimeBond 2.1, Single Bond, Liner Bond 2) and experimental dentine-bonding systems incorporating an antibacterial monomer, 12-methacryloyloxydodecylpyridinium bromide (MDPB), into artificial root caries lesions was evaluated, and the bactericidal activity of each material against Streptococcus mutans or Lactobacillus casei impregnated into demineralized dentine blocks was assessed. All of the commercial dentine-bonding agents were capable of penetrating into the artificial carious lesions to more than 150 microm. The depth of penetration of the experimental systems, which were based on Liner Bond 2, was not significantly different from that of their parent product. Liner Bond 2 primer exhibited the greatest bactericidal effects among the three proprietary dentine-bonding agents tested. Bactericidal activities of experimental primers containing MDPB were greater than those of any other products, and the application of 4% MDPB-containing primer resulted in complete killing of bacteria in demineralized dentine. The results indicate that the penetration of dentine-bonding agents into extensively demineralized root dentine is possible in vitro, and the experimental dentine-bonding systems containing the antibacterial monomer MDPB are capable of killing bacteria within demineralized dentine. This could be of benefit when managing root caries lesions.

Objective To compile an inventory of data from clinical studies on anterior veneer restorations, with special reference to clinical trials to produce a mean survival result using a meta-analysis. Data sources Medline search 1983 to November 1996 using key words ‘dental’ and ‘Veneer’. Study selection A two-stage selection was employed. Initially all non-clinical studies case reports and descriptive papers were excluded. Subsequently all papers which did not meet the following criteria were excluded: English language, 2-year or more follow-up, type, number and location of restoration noted, number of patients stated together with type of restoration, study outcome shown as failure or survival. A quality scoring system was applied to the selected papers and used in combination with the sample size for combining the studies. Results Initially 1056 studies were identified after the initial selection 25 clinical studies remained; this was reduced to 15 at the subsequent selection. Two further studies were excluded, as their data did not allow calculation of survival curves. The cumulative proportion of survival for porcelain and pre-formed acrylic veneer restoration after 3 years is shown in the table below. Conclusion Porcelain veneers show acceptable longevity after 3 years, which appears better than the preformed acrylic type. The evaluative and statistical analysis of clinical veneer restoration studies may be improved. Kreulen C M, Creugers N H J, Meijering A C. Meta-analysis of anterior veneer restorations in clinical studies. J Dent 1998; 26: 345–353