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Background: Age-adjusted death rates for coronary heart disease (CHD) have been decreasing in populations of developed countries. At the same time, CHD in the Asia-Pacific region appears to be increasing in parallel with the 'Westernisation' of diet and lifestyle. More epidemiological information is needed from the Asia-Pacific region in order to be able to predict trends in CHD and to plan resources for treatment. In this paper we outline the study design of a survey of coronary heart disease risk factors in Asia-Pacific countries., Aims: To ascertain and compare in 10 countries: (i) rates of measurement of risk factors; (ii) levels of risk factors, and (iii) management of risk factors., Methods: A retrospective survey was conducted in 180 randomly selected hospitals using a population-weighted sampling frame. Participating countries were Australia, Indonesia, Japan, Korea, Malaysia, New Zealand, the Philippines, Singapore, Taiwan and Thailand. Data covered a 6-month period from the patient's admission to hospital with myocardial infarction or unstable angina. Data included measures of hypertension, smoking, obesity, diabetes, dyslipidaemia and family history of coronary disease. The study design incorporated rigorous quality-assurance methods to ensure reliability., Conclusions: The study will provide data comparable to those from studies in Europe and the USA. Together, these studies will provide an international perspective on coronary risk factors.

Intentional tooth replantation is a last-resort procedure, recommended only when all other techniques, short of tooth extraction, have been exhausted or are impractical. Although most endodontic textbooks describe the procedure, and many reports of intentional replantation have appeared in the dental literature, none have reported use of the technique to retain a removable partial denture abutment tooth. This article presents such a case and the rationale for the decision to intentionally replant. Eighteen-month follow-up clinical and radiographic results are presented.

Different quantities and sizes of peanuts were offered to six human subjects for mastication at two or three experimental sessions during which jaw movements and chewing cycle duration were measured. The amplitude of vertical movement and cycle duration depended on the position of a chew in a sequence of chews (masticatory sequence). Cycle duration also depended on the position of a given masticatory sequence during the first experimental session, the earlier sequences tending to be longer. Lateral jaw movements fluctuated about a reasonably constant value during a sequence and were unaffected by different food inputs. The amplitude of vertical movements increased markedly with an increase in food weight but was unaffected by change in the initial food particle size. These results were analyzed in the light of previous reports on the comminution of peanuts. It is hypothesized that observed jaw movements were unrelated to food particle size but that the amplitude of each vertical movement depended on the volume of food that was broken by the teeth during the next closing stroke. This food volume was provided and selected by bulk movements of the tongue during the preceding jaw opening.

Because residual monomer may cause tissue irritation, we investigated two self-curing acrylic denture-base materials--one a compression type, and the other a pourable material--by means of gas-liquid chromatography. Both exhibited higher residual monomer levels than did heat-cured acrylics, with thick sections having lower values than did thin sections. The pourable material showed lower values than did the compression variety.

All denture base materials are subjected to abrasion during function, but this will be greatest under certain denture cleansing regimens. Two new materials, a 'pour type' and a compression moulding acrylic resin were subjected to mechanical brushing with denture cleansers. It was found that abrasion resistance of the two materials was of the same order, and weight loss was greatest with one of the paste cleansers.

The mycologic findings of Candida albicans or culturally similar yeasts in 70% of the subject sample is consistent with those of other researchers. It is, however, only one of several etiologic factors requiring concomitant study to obtain meaningful results. Use of an antimycotic denture adhesive did not prove to be effective in the treatment of denture stomatitis. Although in the trial it appeared that marginally better results were obtained with the amphotericin medicated adhesive, this could not be substantiated statistically. On retrospective testing in the laboratory, both medicated and placebo materials were found to have an inhibiting effect on the growth of C. albicans. However, it was considered that the beneficial effects noted were probably due to the adhesive and lubricant effects of the test materials in reducing denture trauma in function.

The evaluation of the collated results demonstrated that 86% to 90% of the subjects examined did not have identical dimensions or form of the left and right maxillary central incisors. In over 60% of these subjects the differences were quite substantial.

A investigation of 64 Angle Class I, skeletal Class I dental students showed that the interalar nasal width is a reliable guide for selecting the mold of anterior teeth, and that the incisive papilla provides a stable anatomic landmark for arranging the labial surfaces of the central incisors at 10 mm anterior to the posterior border of the papilla. The mesiodistal width of the set of anterior teeth (four incisor and the mesial halves of the canines) should be determined by adding 7 mm to the patient's nasal width (Fig. 8). The tips of canines on the horizontal plane, should be set on a line which passes through the posterior border of the incisive papilla (Fig. 9). The distance between them should equal the patient's nasal width, so that from the frontal view they would each seem to lie on a perpendicular line drawn from each of ala of the nose (Fig. 6).

It is important that denture base materials should be colour stable, yet some self curing materials do not fulfill this requirement. Two newly introduced materials, one a 'pour type' resin, were investigated using a sophisticated colorimetric instrument to assess colour changes that might result from contact with water and denture cleansers. Both materials showed measurable colour changes following a two week soaking period, but these were barely perceptible to the eye. The possible reasons for colour instability are discussed.

The outline forms of both maxillary central incisor teeth were compared with the "actual" and "apparent" face-forms in 70 subjects, to determine whether a close similarity of face-forms and tooth forms exists, which would support the "law of harmony" method for the selection of replacement of teeth. The results of the investigation do not support the contention of Williams but rather invalidate this method of teeth selection because more than two-thirds of the individuals showed no similarity between face-form and incisor tooth form.