Publications by authors named "Andrew G Mason"

Objectives: This in vitro work investigates the potential of ostrich eggshell as a substitute for extracted human teeth in preliminary screening studies on dental erosion. Additionally, it aims to demonstrate the potential of ostrich eggshell compared to human enamel in evaluating the efficacy of a preventive agent in protecting against dental erosion, using an artificial mouth model.

Methods: The experiment utilized 96 erosion testing specimens from each substrate, human enamel, and ostrich eggshell.

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The aim of this study is to identify topics (knowledge and skills) from the dental curricula that would benefit from having a 3D learning resource using an exploratory sequential design method. The first phase targeted stakeholders from a Scottish dental school. Seven focus groups and three interviews disclosed 97 suitable topics for 3D technology development.

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This work reports upon the design, build and operation of an artificial environment (Saltus) that sought to simulate the process of in vivo dental erosion upon human enamel. A novel testing environment, housed 8 erosion testing substrate specimens, that on separate occasions were subject to 4 different experimental diets, of increasing erosive challenge, simulating the consumption of an acidic beverage. Each set of specimens was subjected to one of the experimental diets only.

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Introduction: The aims of this study were to establish a safe technique for selective stimulation of nerves in human tooth-pulp during long experiments and to validate its use even with stimuli of high intensities.

Methods: A custom-made veneer containing 2 silver wire-conductive cream electrodes was attached with cement to the labial surface of an upper central incisor tooth. A variety of stimulus intensities were applied, and sensory and reflex responses from jaw-closing muscles were recorded.

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Pushing a tooth results in movement of the tooth and reflex inhibition of activity in jaw-closing muscles. The aims of this study were to determine how much tooth movement is required to elicit such reflexes and whether this is dependent on the point of force application to the tooth. Eight experiments were performed on six volunteer subjects.

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Inhibitory jaw reflexes are believed to be important for protecting the teeth and temporo-mandibular structures from damage during sudden or forceful biting or mastication. Accordingly, alterations in these reflexes are sometimes implicated in aetiologies proposed for oro-facial pain syndromes, although the association is not well-established. We now aim to develop a method for quantifying objectively inhibitory jaw reflexes evoked by natural tooth contact.

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Aims: This investigation sought to: (a) determine the agents used by nine dentists to treat dentine hypersensitivity and measure their effectiveness; (b) evaluate the adoptive ease and apparent success of the most effective treatment when used by all nine dentists; and (c) validate a novel categorical ranking score for dentine hypersensitivity.

Methods: A clinical audit methodology was used in the setting of general dental practice. In the initial data-collection round, patients presenting with dentine hypersensitivity were treated using the dentist's favoured regimen.

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Objective: In humans, stimulation of nerves in or around teeth can evoke inhibitory jaw reflexes. Previous studies had suggested that there may be subtle differences in the timings of the responses. The aim of the present study was to investigate this by comparing reflexes evoked by electrical stimulation of a tooth and of the adjacent tissues in individual subjects.

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In humans, inhibitory jaw reflexes can be depressed by painful stimulation of remote parts of the body. The underlying mechanisms may involve diffuse noxious inhibitory controls (DNIC). Animal experiments have shown that the neurons which may mediate DNIC show spatial encoding (i.

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In human beings, inhibitory jaw reflexes can be depressed by painful stimulation of remote parts of the body. Since similar effects can be produced by the stress of anticipating pain, we wished to investigate whether the effects of remote painful stimuli are dependent on stress. EMG recordings were made from a masseter muscle while subjects maintained activity in the muscle at approximately 12.

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Because loading during chewing is not totally predictable and jaw-closing muscles are strong and act over short distances, feedback from oral receptors is important in the control of mastication. Information on such feedback can be obtained by studying reflexes in jaw muscle EMGs. This review will deal with the contribution of reflex mechanisms to modifying motor neuron activity during chewing, and the dependency of reflex sensitivity on motor task, phase of movement, and site of stimulation.

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This paper describes a new protocol that addresses the question of whether, in human experiments, modulatory effects of remote nociceptive conditioning stimuli on reflex responses are mediated by the stress induced by the conditioning stimuli. The protocol has been illustrated by a study into the effect of a remote nociceptive conditioning stimulus on an inhibitory jaw reflex. Electromyograms were recorded from an active masseter muscle and inhibitory reflexes were evoked by applying electrical stimuli to the upper lip.

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The purpose of the study was to investigate whether jaw reflexes evoked by selective stimulation of periodontal ligament me canoreceptors are susceptible to modulation by remote noxious stimulation. Experiments were performed on 10 volunteer subjects. Skin surface recordings were made from the jaw-closing masseter muscle.

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