摘要:

SummaryResults of a study of 215 male subjects from Siwa oasis are presented. The Siwian community is representative of the Bedouin communities in the Egyptian western desert. The population belongs to a characteristic ethnic group, living in a primitive way. The most prevalent symptoms were headache (29%), pain in the ear (24%) and clicking joint sounds (19%); 84% of the subjects suffered from tenderness of one or more of the masticatory muscles; 8% of the subjects had painful movements of the mandible.The results extend knowledge of the distribution of jaw dysfunction complaints into hitherto uninvestigated communities.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01468.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryToothpaste solution exerts an inhibitory effect on dissolution of enamel in acidic solution. The presence of a detergent will not predispose enamel to acid dissolution or affect the inhibitory effect of fluoride on dissolution.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01469.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryYoung adults (Md 24) and Adults (Md 41) were examined with respect to the distribution of occlusal contacts in molars, premolars and anterior teeth when exerting light and hard pressure respectively in the habitual intercuspal position.There was no difference between the right and left side and the number of contacts per tooth was low. In all groups of teeth there was a smaller number of contacts at light pressure. The lower number of contacts at light pressure in Adults when comparing with Young adults was related only to the anterior teeth. The increase of the number of contacts at hard pressure was greater for the anterior teeth than for the molars. In cases where there was a greater number of contacts present on one side, the distribution did not alter significantly when changing from light to hard pressure. Neither did the articulator‐adjusted intercuspal position differ significantly in this respect from the clinically recorded intercuspal position at hard pressure. A further result was that about 50% of the individuals had 60% or more contacts on one side at light pressure.These findings stress the importance of meticulous care when performing occlusal adjustment, as the number of contacts per tooth is low and indicates the need for observing the difference between light and hard pressur

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01470.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryMechanical attachments used to improve retention of overdentures have their limitations. With the recent development of the cobalt‐samarium magnet an alternative method of achieving increased overdenture retention is offered. The most suitable form of magnet appears to be of a reverse split pole design with a ferromagnetic disc or keeper which will ensure a closed magnetic field. Clinical techniques involve conventional endodontic therapy, and the basic method of overdenture construction can be followed with only minor modificatio

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01471.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryThe effect of γ1and γ2on the creep deformation of dental amalgams has been investigated. It has been shown that the creep of a conventional amalgam is not dependent on γ1as was previously reported. Rather it is strongly influenced by γ2and its volume fraction. It has been speculated that Sn‐rich grain boundaries also enhance creep by facilitating grain boundary sliding. The reported correlation between creep and marginal fracture has been explained in terms of this dependence of creep on corrosionprone Sn‐rich microstructural constituents of a

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01472.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryAn investigation was conducted to determine the reproducibility of the position of a maxillary cast in two widely‐used semi‐adjustable articulators when a face‐bow transfer was repeated ten times for the same individual.The results obtained with the Dentatus AEB, Whipmix Quickmount and Almore transfer bows were compared. The variations in cast position rarely exceeded ±1.0 mm in any of three planes of space and although the results suggested a ranking in accuracy of the three instruments, all were considered clinically acceptable.On the basis of the results observed, face‐bow transfer appears to be a reliable clinical procedure and accuracy in the determination of reference locations is unlikely to be negated by subsequent transfer errors, provided that appropriate care is

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01473.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryTwo methods for determining internal stresses in tooth structures were compared under a specific load condition. The numerical method of the finite element method has a definite number of advantages over the experimental photoelastic method. The numerical results obtained by the first method are in reasonable conformity with those obtained by the latter. In addition the sensitivity of the finite element method towards variation of a number of relevant parameters has been studied.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01474.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SummaryEight human subjects exercised maximum voluntary tooth clenching until there was complete exhaustion of the contracting jaw muscles (isometric endurance time). During the isometric muscle contractions the myoelectrical currents of the masseter and anterior temporalis muscle were sampled by bipolar surface electrodes, integrated, and cumulatively stored. The myoelectrical activity was studied at recording thresholds of 1 μV and 40 μV, i.e. all action potentials below threshold level were ignored. The observations suggested that the number of fast glycolytic and fast oxidative glycolytic motor units in the masseter muscle might have exceeded that in the anterior temporalis muscle; and/or the size of the masseter muscle units might have been larger than that of the anterior temporalis muscle unit

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1983.tb01475.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY