Cellular responses to metal ions released from implants.

In the process of calcified tissue formation, cells secrete a protein-rich matrix into which they add a metal ion that nucleates in the presence of phosphorus to form an inorganic salt (usually calcium hydroxyapatite). Cellular and tissue responses to metal ions-released from implants, for example-can therefore be considered from the perspective of how cells handle calcium ions. A critical factor in determining cellular toxicity will be free ion concentrations and the competitive interactions that occur in a physicochemical manner. Three of the parameters used to assess the biocompatibility of implant materials are (1) the ability to influence mitotic activity, (2) intercellular adhesion, and (3) promotion of cell death. A spectrum of responses to free intracellular calcium ions can be identified, ranging from presence of the ion being essential for cell division through to an excess of the free ion that results in cell death (apoptosis). In between these extremes, cells may become postmitotic and express phenotypic variations as they adapt to their environment and establish equilibrium to maintain intracellular calcium homeostasis. The response of cells to implants can be linked to ions released and interactions between these and other ions and/or molecules present in the tissues, similar to the manner in which cells handle calcium ions.

Dental therapists and dental hygienists educated for the New Zealand environment.

New Zealand has a long history of dental care provided by school dental nurses, now known as dental therapists. The nature of their training courses, although delivered in different centers, had remained relatively constant until 1999 when educational responsibility was transferred to the universities. Dental hygienists were not trained in New Zealand until 1994, with the exception of the New Zealand Army hygienists. Since 2001, the education of both dental therapists and dental hygienists has been the responsibility of the universities. Significant and progressive changes in educational delivery have occurred since then, which have culminated in three-year degree qualifications for dual-trained oral health professionals. Factors influencing this change included increased professionalism associated with the new legislative requirements for registration, workforce shortages, and enhanced educational and clinical practice requirements. The Bachelor of Oral Health degree at the University of Otago has an added emphasis on social sciences and incorporates aspects of learning relating to New Zealand's cultural heritage. We explore in this article the rationale for the introduction of a Bachelor of Oral Health in New Zealand and how it is designed to equip graduates as professionals in oral health.

Dental therapists: a global perspective.

In 1921, New Zealand began training school dental nurses, subsequently deploying them throughout the country in school-based clinics providing basic dental care for children. The concept of training dental nurses, later to be designated dental therapists, was adopted by other countries as a means of improving access to care, particularly for children. This paper profiles six countries that utilise dental therapists, with a description of the training that therapists receive in these countries, and the context in which they practice. Based on available demographic information, it also updates the number of dental therapists practising globally, as well as the countries in which they practice. In several countries, dental therapy is now being integrated with dental hygiene in training and practice to create a new type of professional complementary to a dentist. Increasingly, dental therapists are permitted to treat adults as well as children. The paper also describes the status of a current initiative to introduce dental therapy to the United States. It concludes by suggesting that dental therapists can become valued members of the dental team throughout the world, helping to improve access to care and reducing existing disparities in oral health.

Review of oral pathology service, Medlab Dental, University of Otago, 2002-2005.

The School of Dentistry of the University of Otago operates a diagnostic oral pathology service, Medlab Dental, as a joint venture with the private pathology service Medlab South. This report reviews the use of the service in 2005 and provides information on current activities that highlights the importance of oral pathology diagnostic services in patient management.

Surface-active fungicidal D-peptide inhibitors of the plasma membrane proton pump that block azole resistance.

A 1.8-million-member D-octapeptide combinatorial library was constructed in which each member comprised a diversity-containing N-terminal pentapeptide and a C-terminal amidated triarginine motif. The C-terminal motif concentrated the library members at the fungal cell surface. A primary screen for inhibitors of Saccharomyces cerevisiae and Candida albicans growth, together with an in vitro secondary screen with the S. cerevisiae plasma membrane ATPase (Pma1p) as a target, identified the antifungal D-octapeptide BM0 (D-NH(2)-RFWWFRRR-CONH(2)). Optimization of BM0 led to the construction of BM2 (D-NH(2)-RRRFWWFRRR-CONH(2)), which had broad-spectrum fungicidal activity against S. cerevisiae, Candida species, and Cryptococcus neoformans; bound strongly to the surfaces of fungal cells; inhibited the physiological activity of Pma1p; and appeared to target Pma1p, with 50% inhibitory concentrations in the range of 0.5 to 2.5 microM. At sub-MICs (<5 microM), BM2 chemosensitized to fluconazole (FLC) S. cerevisiae strains functionally hyperexpressing fungal lanosterol 14alpha-demethylase and resistance-conferring transporters of azole drugs. BM2 chemosensitized to FLC some FLC-resistant clinical isolates of C. albicans and C. dubliniensis and chemosensitized to itraconazole clinical isolates of C. krusei that are intrinsically resistant to FLC. The growth-inhibitory concentrations of BM2 did not cause fungal cell permeabilization, significant hemolysis of red blood cells, or the death of cultured HEp-2 epithelial cells. BM2 represents a novel class of broad-spectrum, surface-active, Pma1p-targeting fungicides which increases the potencies of azole drugs and circumvents azole resistance.