摘要:

summaryThe effect of controlled oral hygiene was studied in 31 elderly overdenture patients involving 72 abutments over a period of 5 years. Intensive instruction and motivation in oral hygiene care were carried out prior to prosthodontic treatment and two to four times yearly during the study period. The initial dental and periodontal conditions were very poor, with a mean loss of proximal bone adjacent to the abutments of 61%. During the study period, it was possible to maintain mean plaque index scores of 0.45−0.73 and mean gingival index scores of 0.89−0.95 adjacent to the abutments. There was no relationship between the patients' initial plaque index score and the oral and denture hygiene observed during the study. There was spontaneous regression of 4–5 mm periodontal pockets, whereas deeper pockets persisted. Seven abutments were extracted due to periodontal complications. Caries was a minor problem which could be controlled by hygienic measures, topical fluoride or fillings. The present study has shown that it was possible to maintain teeth as overdenture abutments to a large extent in elderly patients initially having a poor dental and periodontal s

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00203.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryAny crown or inlay preparation will be accompanied with pulpal involvement and possible altered biomechanical and/or viscoelastic properties concerning the treated tooth. This study was aimed to assess this influence in terms of differences in interocclusal discrimination threshold value, before and after rehabilitation with gold inlays and by composite resin bonded ceramic inlays. Twenty patients were included and treated with one gold and three ceramic inlays each. For purposes of determining the discrimination threshold between the inlays and antagonizing teeth, plastic foils of different thicknesses were used. Each inlay position, as well as a pair of control teeth, were tested before and after treatment. Before rehabilitation an interocclusal and discrimination threshold of 24μm at the level of 80% right answers were determined. Treatment with inlays, however, resulted in a significantly different and increased threshold for every tooth/inlays combination. No significant differences between the sessions were recorded for the control teeth. It could be concluded that, in the short term, an oral rehabilitation with inlays and in particular bonded inlays will influence mechanosensitive afferents

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00204.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryVarious methods of diagnosing occlusal caries have been described, but only visual, clinical examination and radiographic examination are commonly used in dental practice. This laboratory study investigated the ability of 12 examiners to detect the presence or absence of occlusal caries in 48 extracted molar teeth using these two techniques. The presence or absence of caries was subsequently verified by sectioning the teeth. Diagnosis from visual examination was poor, only 48.7% of lesions in dentine being detected. Radiographic diagnosis was better with 62.2% of dentine lesions being found. However, this increase in sensitivity of the diagnosis was accompanied by a decrease in specificity with the number of false positive diagnoses increasing when the radiograph was used. Therefore, although the bite‐wing radiograph may be regarded as a safety net for the diagnosis of occlusal caries, it must be interpreted with caution bearing in mind the possibility of false positive diagnose

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00205.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryVarious spatial and morphological aspects of the temporomandibular joint may be involved in the development of TMJ sounds. The present study examines their contribution to the prediction of sounds. A non‐patient sample was studied using sensitive sounds measurement and panoramic radiography. It was found that temporomandibular joint sounds are common in asymptomatic subjects showing substantial variation in several spatial and morphological parameters. An autonomous contribution of spatial relationships, asymmetries or morphology of bony structures to the prediction of joint sounds could not be detected. When unilateral sounds were present, they were more likely to be found on the side with the less steep condylar movement path. Joint imaging is not indicated in the detection of relationships between bony structures and their eventual asymmetries and joint sound

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00206.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryPins and root canal posts are generally considered indispensible aids in clinical restorative dentistry. To secure the long‐term efficiency of pins and posts, such devices should be of sufficient strength to carry the relevant loads. It is, however, essential that their properties do not decline as a consequence of corrosion, or that corrosion of metallic pins and posts does not cause unfavourable effect in contacting biological tissues. The microstructure of certain commercially available dental retention pins and prefabricated root canal posts has been investigated using optical microscopy and standard metallographic techniques. The specimens were then examined by scanning electron microscope and energy dispersive X‐ray analysis (EDAX). The results indicate differences in microstructure and condition between the types examined. The results also showed the presence of included particles in some pins and posts. These differences and the presence of inclusions may have an important bearing on service life and corrosion resista

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00207.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryAnin vitroexperimental model has been developed for erosive lesion formation in dental enamel which can mimicin vivoconditions at the tooth surface. The features of this model provide a very reproducible method of producing erosive lesions in several teeth under identical conditions which can be varied to allow examination of a number of different parameters. A replica impression technique has also been developed for subsequent non‐destructive microscopic examination of the lesions and comparison within vivolesion

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00208.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryThis investigation determined the efficiency and rate of cure of polymeric luting agents when cured under manufacturers' instructions with the appropriate visible light source, and under conditions where light was excluded and curing was reliant on the chemical reaction only. Indentation hardness was used as a reflection of conversion. There was a rapid increase in hardness immediately after light curing followed by a steady increase in hardness over the next 24h. The non‐irradiated chemically cured samples exhibited steadily increasing hardness over 24h, but were too soft to test in the initial 30 min. Hardness values were extrapolated to obtain predicted values of flexural strength. Dual curing was more effective than chemical curing alone. The results suggest that the formulation of dual cure materials is a balance between high levels of conversion in all aspects of the restoration and colour instability due to amine degradation. Clinically there may be poorly cured areas in the deeper aspects of a deep cavit

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00209.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryThree subject groups who have shown different biting forces were examined in order to investigate whether the physiological phenomenon that the duration of the silent period (SPD) of the masseter muscle would be influenced by background activities of the muscles. They were classified into child (CN,n= 10) and adult groups; the adult group was then further subdivided according to the strength of maximum biting force into a normal group (AN,n= 10) and a low biting force group with some symptoms (AS,n= 5). SPD was observed in maximum) and biting on a transducer (50N, 100N and maximum). With increase of muscle activities, SPD was significantly decreased in the AN and CN groups, whereas no significant changes were found in the AS group. When comparing SPDs among the three groups at the same voluntary effort, the AN group exhibited the shortest SPD followed by the CN and AS groups. The results suggest that SPD was positively influenced by the strength of the background activities of the muscles and that immaturity of the masseters in terms of muscle activity could affect the SPD.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00210.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summarySurface electromography was used to study the function of the anterior temporal, surface masseter, deep masseter and anterior digastric muscles of 14 patients after complete rehabilitation of occlusion with fixed prostheses and/or removable partial prostheses. All patients had a balanced occlusion with protection by non‐working side contacts during lateral excursion. Mean resting myoelectric activity was 2.5‐3.8 μV, showing no hypertonia or muscular spasm. When patients clenched their teeth (i.e. exerted maximum voluntary occlusal force in centric occlusion), the anterior temporal muscles were the most active, followed by the surface masseters; the digastrics were significantly less active. During lateral displacements, the muscles exhibiting significantly higher potentials than the other muscles monitored were the working side anterior temporal muscle and the contralateral surface masseter. During mastication, the muscle that was most active in relation to its contralateral homologue was the working side surface masseter, the difference between the two being statistically signifi

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00211.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

summaryThe primary author, an experienced dentist, cut bovine enamel and dentine horizontally and vertically with diamond points driven by an air‐turbine, while the rotational cutting speeds and applied loads were simultaneously monitored. Three cutting techniques employed here were successive cutting with moderate force (S‐m); intermittent cutting with moderate force (I‐m); and intermittent cutting with a smaller force (I‐s). It was found that the cut contact time of S‐m, I‐m, and I‐s cuts were about 10s, 0.4s and 0.25s, respectively. The maximum applied load during cutting varied, depending upon the cutting direction and the cutting technique. Vertical S‐m cut of enamel resulted in the largest applied load of around 105g, while horizontal I‐s cut of dentine brought about the minimum (approximately 35g). Cutting volumes of dentine tended to exceed those of enamel. It was confirmed that the I‐m cut produced larger cutting effectiveness of diamond points on both enamel and dentine compar

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1995.tb00212.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY