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Biomedical subjects

A M Boyle

Publications and source records attributed to A M Boyle.

7 recordsLinked to original sources
PubMed1995

The effect of tray material and surface condition on the shear bond strength of impression materials.

This study compared the adhesive shear bond strength of three selected impression materials with that of thermoplastic and acrylic resin tray materials as a function of surface preparation. Polyether (Impregum), polyvinylsiloxane (Reprosil), and polysulfide (Permlastic) impression materials were evaluated on smooth, rough, and contaminated tray surfaces. Smooth surface samples were formed against glass and served as the control groups. Experimental groups consisted of samples contaminated with artificial saliva and rough surface samples that were abraded with 110 microns of Al203. A total of 126 samples were subdivided into 18 groups of seven specimens each. Each sample consisted of a 1 inch square, 3 mm thick mass of an impression material sandwiched between the prepared surfaces of a pair of resin plates. Each specimen was tested in a universal testing machine for adhesive shear bond strength. Data were analyzed with three-way analysis of variance and Scheffe's test. The results indicated that the thermoplastic resin material had better adhesive properties than the acrylic resin. For both tray materials mean adhesive shear bond strengths for Impregum and Reprosil were significantly greater than those of Permlastic. Tray surface contaminated with saliva decreased the adhesive shear strength at the tray adhesive impression interface.

Acrylic Resins↗
PubMed1987

Mechanisms of tooth eruption in a computer-generated analysis of functional jaw deformations in man.

Two mechanisms that contribute to tooth eruption are proposed from analysis of the human jaws as elastic structures which are deformed intermittently under functional occlusal loads. One possible source of eruptive force is the transient pressure gradient established within each jaw as it is deformed. The second source, suggested by the computer model, is a consequence of the tension placed on periodontal-ligament fibres as individual tooth-sockets are distorted within the deformed jaws.

Bite Force↗
PubMed1986

Assessing psychomotor skills: the role of the Crawford Small Parts Dexterity Test as a screening instrument.

The Crawford Small Parts Dexterity Test, a performance test designed to measure eye-hand coordination, was administered to 71 freshman dental students prior to their first-semester classes and again in their senior year. Zero-order and stepwise multiple regression analyses compared the predictor variables commonly used for dental school admissions decisions and the dexterity test scores with the mean performance in four preclinical laboratory courses and overall dental school performance. The results indicate that CSPDT assessment may improve selection accuracy when used with current measures. Significant gender interaction effects were observed.

Aptitude Tests↗
PubMed1976

Genetics, drug dependence and schizophrenia.

It has been suggested that drug dependence is a substitute for schizophrenia in young patients and that drug dependence protects them from schizophrenic breakdown. Assuming the correctness of the genetic basis for schizophrenia, it was postulated that persons known to be dependent on heroin would have a higher genetic loading for schizophrenia if the hypothesis was true. An examination of the family backgrounds of 82 drug dependent persons failed to find supporting evidence for the belief that drug dependence is a substitute for schizophrenia in young persons.

Adolescent↗