摘要:

SummaryClassification is necessary to most forms of thought, and the scientific method requires particular refinement of this process in order to formulate its laws. But there is nothing fundamental about any classification; its categories are chosen for a particular purpose only, and often at least some of the subjects do not fall readily into any class. Furthermore, since only few of an individual's characteristics are used as classifying attributes, individuals themselves become submerged in the classes, and their individuality lost in the scientific laws that arise therefrom. Desiderata of science and uniqueness are therefore opposed—and they are irreconcilable because absolute knowledge is either non‐existent or unattainable. Thus, the decision as to whether an individual patient is healthy or diseased must be made on the basis of diagnostic laws which, as far as the individual is concerned, are inaccurate and may turn out to be spurious or even meaningless. These laws are therefore only guide‐lines which must be ‘re‐individuated’ in clinical practice. In essence, the individual's health depends on the individua

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00162.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryIn this study the perception of chewing is investigated in forty‐three subjects with a shortened dental arch (SDA) by means of an interview. A group of fifty‐four subjects with a complete dentition was used as a control group. The aim was: (i) do subjects with a SDA have a higher risk of chewing problems, and (ii) do they have different food perception and food selection leading to change in their diet?The results show that for subjects with a SDA the chewing function, food perception, food selection and actual food consumption are hindered within an acceptable deg

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00163.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryIn this laboratory study, the effect of retention grooves in the proximal portion of class II cavities on the marginal microleakage using light‐cured composite resin was examined. The retention grooves were placed at the axio‐facial and axio‐lingual line angles and in the gingival floor of the cavities.The teeth were restored with Herculite composite resin with etching and dentine bonding and polymerized in two different ways: (i) a single mass of restorative material was polymerized all at once; and (ii) incrementally placed amounts of restorative material were each polymerized separately until the cavity was completely filled.Marginal microleakage was evaluated by the degree of dye penetration at the gingival margin of the restorations after suitable thermocycling procedures.It was concluded that marginal microleakage was significantly reduced when the composite resin was placed and polymerized incrementally, and that no advantage was gained from retention grooves with this incremental technique. However, when polymerizing in one single mass of material, retention grooves were found to be necessary in order to reduce marginal microleakage at the gingival

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00164.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryThe effect of three different powder/liquid ratios of one zinc phosphate cement on the early retention of a standard crown on metal and tooth dies was investigated. Two different seating pressures were evaluated. The results indicate that the effect of variation in the powder/liquid was not significant. The part played by the seating force was significant, the higher seating force resulting in a greater force being required for displacement after 1h. Greater forces of removal were required when tooth dies were used.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00165.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryIn order to assess the tissue compatibility of the hybrid materials for the dental implant (hydroxyapatite, titanium oxide and titanium nitride coated titanium alloys), tissue response to these materials implanted in the rat subcutaneous tissue was histologically examined. Initial inflammatory response was less evident in titanium oxide coated and non‐coated titanium alloys. All materials were encapsulated by thin fibrous connective tissues. The membrane thickness of hydroxyapatite coated titanium alloy was significantly higher than that of titanium nitride coated one. These results suggest that all materials possess favourable tissue compatibility and may encourage clinical use as the dental implan

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00166.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryThree dental amalgams were mixed in a number of different mixing capsules. Compressive strength specimens were prepared using a clinically relevant technique and tested at 1 h and 7 days. The results showed that the early compressive strength of an alloy was influenced by the mixing capsule, and suggested that internal capsule geometry may be an important contributary factor in capsule performance. With one exception, there was a marked difference between the compressive strengths produced under the present method and those reported by manufacturers under test conditions laid down in standards specifications.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00167.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryTwenty‐two human subjects performed sustained voluntary contractions of the mandibular elevator muscles firstly without and secondly with visual biofeedback. The level of electromyographic activity of the masseter muscle during the second clench exceeded that during the first clench by a mean of 36%. This differential indicates the ability of the subjects to override the central factors which normally limit muscle activity during a fatiguing contractio

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00168.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryThe aim of this study was to measure the rise in temperature during: (i) a single cycle of a curing light unit, (ii) the polymerization of a layer of light‐cured lining material, and (iii) the polymerization of a light‐cured posterior composite material, and also during combinations of these individual procedures. Experimental work was undertakenin vitroand measurements were made using a thermocouple placed centrally in an insulated PTFE well. Large temperature rises occurred with the use of the curing light alone. The lining material itself did not contribute significantly to the rise in temperature during curing, nor did it provide thermal insulation from the output temperature emitted by the light guide. The presence of a layer of posterior composite reduced the temperature transmitted from the light but the residual temperature rise transmitted was still of such a magnitude as to cause concern regarding possible thermal injury to the p

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00169.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryTwenty‐five subjects of three nationalities carried out Gothic arch tracings. Measurements between the side arms were compared with the upper intercuspid distances measured in the same subjects. A relationship was found which may be of value in the setting up of anterior maxillary denture teet

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00170.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

SummaryMandibular movement and masticatory performance were evaluated in the edentulous patients with an experimental denture using posterior artificial teeth of different occlusal schemes in order to determine the criterion for the selection of posterior artificial teeth.Lower masticatory performance was observed with non‐anatomic posterior teeth than with semi‐anatomic or anatomic ones regardless of the condition of residual ridge and inclination of the horizontal condylar guidance. The value of the lateral component of the masticatory cycle was closely related to the inclination of the cusp and the value of masticatory performance. This suggested strongly that the component could be a criteria for the selection of the type of the artificial posterior te

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1988.tb00171.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY