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A rapid-cure polymerization of cure, including a terminal boil, with respect to transparency, residual monomer, mechanical properties, and generation of gaseous porosity. It was found that in order for porosity-free resin to be produced during rapid curing, a low concentration (approximately 0.26%) of benzoyl peroxide initiator in the powder component is vital, and a very small concentration (approximately 0.025%) of the chemical activator dimethyl-p-toluidine in the monomer component is an advantage. Mechanical properties were only influenced where substantial porosity existed, but it was recognized that a material "tailor-made" for rapid curing would be most welcome.

A comparison has been made of the effects on the gingivae of occlusally and gingivally approaching clasps. The effect on the gingivae has been assessed by measuring plaque accumulation, crevicular temperature and microbial distribution in patients and students wearing appliances. Habitual and nil oral hygiene regimes have been used to demonstrate changes. It was concluded that the gingivally approaching clasp is potentially damaging.

A sample of fifty-three partially dentate subjects who had had partial dentures provided in the last 3 years completed a personality questionnaire (Cattell's 16 PFQ). At the same time they completed a clinical questionnaire and were examined by two of the authors. The purpose of this was to assess the patients' satisfaction with their partial dentures. The results of the personality questionnaire showed that this group of partial denture wearers differed from the general population on only two factors. They were less intelligent and more self-sufficient. Interestingly they differed from a similar group of complete denture wearers on a further three factors. The partial denture group were more self-assured, self-sufficient and more relaxed. On the basis of the clinical questionnaire and examination, five partially dentate patients were found to be dissatisfied. Their personality scores were significantly more unstable than the satisfied group of partial denture wearers. Although based on a relatively small group, the results do suggest that personality may have a marked effect on the patients' adaption to partial dentures. When compared to a similar group of edentulous patients, marked differences were found, suggesting that the loss of the natural teeth in some individuals affects behaviour.

A review and evaluation of the literature on mastication has been undertaken. Part I discusses the form of the masticatory cycle in the natural and artificial dentitions, including the controversial question of whether tooth contact occurs during function. Part II reviews the literature concerning the speed of movement of the mandible, rate of chewing, and the forces developed in chewing. Part III describes masticatory efficiency and performance, the effect of food on masticatory function, and incorporates a summary of all these three papers.

Recently, the authors realized that an evaluation of the literature on mastication had never been undertaken, and it is hoped that this review presented in three parts, will be of value, not only to the dental clinician, but to other scientists working in associated fields. The first paper discusses the form of the masticatory cycle in the natural and artificial dentitions, including the controversial question of whether tooth contact occurs during function. The second paper reviews the literature concerning the speed of movement of the mandible, rate of chewing and the forces developed in chewing. The final paper describes masticatory efficiency and performance, the effect of food on masticatory function, and incorporates a summary of all these three papers.

This investigation examines the variation in strain on maxillary dentures worm by five subjects in clenching. Strain gauges were attached to each denture in four places. The strain was measured with the posterior teeth in their normal position and then again when these teeth had been moved buccally and palatally. The strain levels varied when the posterior teeth were moved palatally or buccally, but the tension or compression response of the gauges was consistent. The strain level agreed generally with those reported by other workers.

Two experiments were conducted to test the antiepileptic properties of CL 218-872, a triazolopyridizine reported to have anxiolytic and anticonvulsant effects without accompanying sedative and ataxic effects. In Experiment 1 pretreatment with CL 218-872, a recently synthesized and potent triazolopyridizine, reduced kainic acid-induced convulsions and subsequent neuropathology in rats given ip doses of 25 mg/kg or greater. CL 218-872 at doses of 50 mg/kg or greater was more effective than a high dose of diazepam (20 mg/kg) in blocking status epilepticus-like convulsions and the associated widespread neuropathological sequelae. Moreover, diazepam pretreatment was associated with a higher mortality rate than CL 218-872. In Experiment 2 the efficacy of intervention with 20 mg/kg diazepam was compared with that of 50 mg/kg CL 218-872 in suppressing ongoing convulsions and reducing subsequent brain damage following a convulsant dose of kainic acid. Although CL 218-872 and diazepam were equally effective behaviorally (i.e., in suppressing kainic acid-induced convulsions), CL 218-872 was superior in its ability to reduce subsequent neuropathology, especially in the hippocampus and neocortex. Because kainic acid has been suggested as a model for human status epilepticus, CL 218-872 may be a potentially therapeutic treatment for this disorder.