BACKGROUND: Dental Ethics is still in its infancy. More research investigating ethical issues in dental practice is required, and subjecting dentists to critique by their peers is one available strategy. METHODS: A prioritized list of ethical issues had been derived in a previous qualitative study aimed at examining the concerns of a group of Iranian dentists about ethical issues in dental practice. The current study used the most highly ranked issues to develop a series of ethical vignettes and accompanying questionnaire. Dentists were asked to rate each of four or five possible actions in response to every vignette, according to the expected prevalence of behaviour among Iranian dentists and its degree of ethical soundness. Two hundred and four Iranian dentists, predominantly general practitioners, participated in the study. RESULTS AND CONCLUSIONS: The three top themes, all directly related to clinical dental practice, were: not taking responsibility for one's errors, performing procedures without adequate competence, and over-treatment (or unnecessary treatment). Less important issues included: unprincipled behaviour towards disadvantaged patients, unprofessional discussion of a colleague's work, and inappropriate manners towards patients. The female respondents showed more concern regarding the prevalence of unethical behaviour of dental professionals than did their male peers.

In this paper, we compute piecewise constant bounds on the solution of mixed nonlinear Volterra-Fredholm integral equations. The enclosures are in the form of intervals which are guaranteed to contain the exact solution considering all round-off and truncation errors, so the width of interval solutions allows us to control the error estimation. An iterative algorithm to improve the accuracy of initial enclosures is given and its convergence are also investigated. Our numerical experiments show that the precision of interval solutions are reasonable in comparison to the classical methods and the obtained conditions and initial enclosure of the proposed algorithm are not restrictive. Mathematical subject classification: 65G20, 45G10, 65G40.