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Biomedical subjects

A H Brook

Publications and source records attributed to A H Brook.

81 records · Page 5Linked to original sources
PubMedDate not supplied

Reproducibility of quantitative measurement of white enamel demineralisation by image analysis.

The reproducibility of measuring artificial enamel white spot lesions from captured photographic images using computerised image analysis was assessed. Enamel lesions were induced on the buccal surface of 22 human teeth over periods of 3, 7 and 14 days. Standardised photographs were taken from above and below the occlusal plane. These were repeated after 2 weeks. The photographs were converted into TIFF images and mean grey scale levels of the areas of etched enamel were measured using computerised image analysis. Assessment of repeat readings of the same slide showed good reproducibility for photographs taken below the occlusal plane. The limits of agreement showed reasonable agreement between readings carried out on two slides of the same tooth. Capturing TIFF images via 35-mm film and measuring grey scale levels by computerised image analysis is a useful method of quantitative study of early enamel demineralisation. This may be developed for application in the clinical setting.

Adult↗
PubMedDate not supplied

Synergy of binary poly(oxypropylene-oxyethylene) copolymers in reducing retention of Streptococcus sanguis to hydroxyapatite.

Binary poly(oxypropylene-oxyethylene) block copolymer systems have been investigated as a non-bactericidal approach to reduce the retention of an oral bacterium, Streptococcus sanguis. Using a previously validated hydroxyapatite-coated microtitre model to simulate the tooth, the performance of copolymer pairs was measured experimentally. A synergy index and an efficacy index were defined to describe the reduction of bacterial retention by the binary systems that comprise the copolymer pairs. Relationships between the synergy and efficacy indices and their associated compositions are given. The results obtained have been rationalised using a previously developed theoretical approach in conjunction with the binding energetics of species to surfaces.

Bacterial Adhesion↗