Dye-assisted diode laser ablation of carious enamel and dentine.

Carious dentine and enamel from extracted human teeth were ablated using a semiconductor diode laser in conjunction with an applied dye, indocyanine green. This technique offers selective ablation with minimal risk of thermal damage to surrounding dental tissues because uptake of the dye and its irradiation by the laser together control the ablation. In this study, various laser powers and dye concentrations were used to ablate previously extracted human teeth with moderate caries.

Stable lead isotopes in teeth as indicators of past domicile--a potential new tool in forensic science?

A pilot study using stable lead isotope analyses has shown that permanent and deciduous teeth from Eastern and Southern European subjects have completely different lead isotopic compositions to those of Australian subjects. There are statistically significant differences between groups of teeth from subjects from the former Soviet Union (CIS), the former Yugoslavia, United Kingdom, and Lebanon. The isotopic analyses confirm the stability of lead in enamel but suggest that there is exchange of European lead with Australian lead in dentine amounting to about 1% per year.

Lead exchange in teeth and bone--a pilot study using stable lead isotopes.

Stable lead isotopes and lead concentrations were measured in the enamel and dentine of permanent (n = 37) and deciduous teeth (n = 14) from 47 European immigrants to Australia to determine whether lead exchange occurs in teeth and how it relates to lead exchange in bone. Enamel exhibits no exchange of its European-origin lead with lead from the Australian environment. In contrast, dentine lead exchanges with Australian lead to the extent of approximately 1% per year.

Lasers--panacea or paradox?

The first lasers were quite unsuitable for dental use, but the last 30 years have seen the development of a variety of lasers which allow dentists to cut soft tissue without bleeding, remove caries, cut cavities in teeth (usually without pain), cure composite resins rapidly, weld metals with precision, desensitize teeth, sterilize exposed pulps and tissue surfaces and treat skin lesions. Future research may explain why 'soft' lasers appear to promote healing and alleviate joint and muscle pain. There are now many published reports in refereed dental journals covering the various aspects of laser dentistry.

Cleansing and surface modifying agents on implants: fixation and related aspects of aesthetics.

With the prognosis of dental implant replacement of missing teeth becoming better each year, practitioners are focusing their attention on the aesthetic aspects of implantology. However, improvement in aesthetics is only possible with the improvement in implant technology, surgical techniques and prosthodontic procedures. This study aimed at evaluating the effects of various physical and chemical agents on the implant surface; with the view of obtaining increased surface area and biocompatibility.

The captive screw retained sectional denture.

Sectional dentures, where retention is gained, not by flexible metal arms engaging "desirable" undercuts, have occasionally been described in the dental literature. The captive screw retained sectional denture described here is an effective replacement for one or two missing teeth in selected patients. It consists of separate labial and lingual sections, which, when assembled, provide an aesthetic appearance, functional occlusion and excellent retention, with a minimum of abutment tooth preparation and at low cost.

Magnet overdentures.

Magnets were first used for overdenture retention in 1977. A novelty then, they are now an accepted alternative to conventional attachments, and available commercially from a number of manufacturers. Nearly all of them use a "closed field" magnet configuration, which provides optimum retention and eliminates any possibility of magnetic field effects on tissues.

Overdentures with magnetic attachments.

Magnets were used only occasionally for dental purposes several decades ago. Since the advent of rare earth magnet alloys, however, intraoral magnets are shaping the course of aesthetics and retention for both complete and removable partial overdentures. Their benefits include simplicity, low cost, self-adjustment, inherent stress breaking, automatic reseating after denture displacement, comparative freedom of lateral denture movement, a low potential for trauma to the retained roots, and elimination of the need for adjustment in service.

Magnetic denture retention systems: inexpensive and efficient.

A magnetic retention system has been used in more than 6000 complete and partial overdentures, sectional dentures and implant overdentures, with excellent clinical results and patient acceptability. For the overdenture application, decoronated, root-treated teeth are fitted with preformed or cast magnetisable alloy root elements, or 'keepers'. Following conventional denture construction, paired cobalt/samarium magnets in a special configuration are cured into the denture base so that with the denture inserted, the magnets grip the root elements with a retentive force of approximately 300 g per root.

Recent developments in dental plaque disclosants.

The use of erythrosin and fluorescein for disclosing dental plaque in 81 children aged 11-14 years and in 17 young men is reported. Erythrosin stained all plaque. When fluroescein was used, plaque, whether mature or recently exposed to sugars was disclosed under ultra-violet light.

The use of closed circuit television in the teaching of dental technology.

A low cost, single-operator, four-camera, closed-circuit television system was developed to teach dental technology to large classes (120) of second and third year (pre-clinical) undergraduates. Its use permits demonstrations to be conducted, recorded and played back, with no electronic knowledge, little training, and a minimum of preparation and assistance. The field of view is from above the demonstration table, and is selected by pushing button in the size range, 30 cm x 20 cm down to 3cm x 2cm.

Latency and inhibition of human masticatory muscles following stimuli.

Latency-inhibition behavior was always produced in contracting anterior temporal muscles following the application of various stimuli to the teeth and jaws of 31 subjects. Statistically significant differences in duration were generally observed with different procedures. In half of the subjects, the first one or two closures in a sequence of repetitive tapping evoked a longer period of inhibition than subsequent closures.