摘要:

Qualitative and quantitative features of mammalian tooth enamel structure are increasingly being used in taxonomic and phylogenetic analyses, although the variability shown by these traits has not received adequate consideration. This study evaluates the variability displayed by nine quantitative parameters in deep, intermediate, and superficial molar enamel in the closely related bovidsOuis ariesandCapra hircus.These parameters are assessed in terms of the absolute and/or relative variability evinced at a given depth within a single individual. among conspecific individuals, and between species samples. The degrees of relative variability expressed at a given depth are comparable among conspecific individuals and between taxonomic samples. Nevertheless, in many instances, there are significant differences in absolute variability amongst individuals. Also, in four parameters for which individual specimen averages could be calculated, the equality of these means among conspecifics can be rejected. Variability is not equivalent at different enamel depths. The null hypothesis of equality of individual, conspecific variances can be rejected most commonly for parameters measured in deep and superficial enamel, and coefficients of variation also tend to be higher for deep and superficial enamel than for enamel of intermediate depth. The greater variability displayed by deep and especially superficial enamel may be related to the initial onset and the terminal phase of ameloblastic secretory activity. Taxonomic and phylogenetic analyses that utilize quantitative data on enamel structure are valid only if comparisons have been made at equivalent enamel depths.

ISSN:0001-6357    

DOI:10.3109/00016358709094349

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Thirteen adolescents with intact dentitions and 16 with restored dentitions were re-examined after 3 years for signs and symptoms of mandibular dysfunction. In accordance with the results of the first examination, a lower prevalence and degree of clinically recorded dysfunction was found at the follow-up study in subjects with intact teeth than in those with dental restorations. This difference was especially explained by more muscle tenderness recorded in the individuals with restored dentitions than in those with intact teeth. However, the reported symptoms were as a rule mild and relatively evenly distributed in the two groups.

ISSN:0001-6357    

DOI:10.3109/00016358709094350

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

A group of 96 individuals 13 to 15 years of age, with intact teeth, was compared with a control group of 129 individuals with dental restorations, with regard to reported symptoms and functional recordings of the stomatognathic system. Differences between the groups were established, with higher scores in the dentally treated group with regard to the occurrence of headache, distance between the retruded contact position (RCP) and the intercuspal contact position (ICP), lateral slide between RCP and ICP more than or equal to 0.5 mm, and attrition recorded as dentin facets in the lower first molars. The prevalence of different malocclusions was very similar in the groups, and there were practically no sex differences. The findings are not contradictory to the hypothesis that fillings may be related to mandibular dysfunction, but more studies are necessary to explain fully the mechanisms involved.

ISSN:0001-6357    

DOI:10.3109/00016358709094351

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Fifty-four consecutive patients were examined by means of a self-administered questionnaire with questions related to general health and subjective symptoms. In addition, a clinical stomatognathic evaluation was carried out including palpation of the temporomandibular joints (TMJ) and the masticatory muscles and functional analysis of occlusion and mandibular mobility. High frequencies of general diseases were reported. The dominant subjective symptom was headache (62%), which often appeared daily. Symptoms such as pain from the teeth, pain in the face/jaws, and burning sensations in the tongue or oral cavity all appeared in more than half of the sample. The patients were frequently aware of parafunctions such as clenching of the teeth and tongue press. None of the investigated persons were completely free of clinical signs of dysfunction. The most frequent clinical finding was palpation tenderness in the masticatory muscles (96%), generally located in the masseter, temporal, and lateral pterygoid muscles. In more than half of the material TMJ findings were recorded, and more than one-third had TMJ pain. In 35% mandibular mobility was reduced. Occlusal interferences on retrusion and on the mediotrusion side were frequent findings. Impaired general state of health and multiple signs and symptoms of mandibular dysfunction were thus frequent findings in these polysymptomatic patients. Three-fourths of the patients needed treatment for mandibular dysfunction, indicating that great consideration must be made for the functional status of the masticatory system in clinical evaluation of so-called‘oral galvanists’.

ISSN:0001-6357    

DOI:10.3109/00016358709094352

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

We have recently isolated several groups of bacteriophages infectingActinobacillus actino-mycetemcomitansfrom periodontal lesions in patients with rapidly destructive periodontitis. Bacteriophage infection of these bacteria in these patients was restricted to periodontal pockets showing radiographic evidence of recent bone loss and suggests an association between phage-infectedA. actinomycetemcomitansand active periodontal disease. On the basis of the biological activity of bacteriophages we propose a working hypothesis to explain the mechanism by which a phage may increase bacterial virulence in periodontal disease.

ISSN:0001-6357    

DOI:10.3109/00016358709094353

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

The purpose of the present study was to determine the relative importance of a set of predictors for the radiographic change in alveolar bone level over 2 years in a group of 180 subjects and to assess the fit of the applied multivariate model. The included predictors were age, sex, initial bone level, type of initial lesion, tooth type, proximal tooth surface, calculus, and the presence of metal crowns or proximal fillings. The multivariate method of choice was multiple classification analysis. The results indicated that in descending order tooth type, initial bone level, and age were the most important predictors. Sex, calculus, and crown and filling margins also showed significant direct effects (beta) on longitudinal bone loss (p<0.05). However, their relative importance was far less than that of tooth type, initial bone level, and age. Proximal side showed no significant direct effect. Using seven predictors, the applied multivariate model explained 20% of the variance in longitudinal bone loss.

ISSN:0001-6357    

DOI:10.3109/00016358709094354

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Forty-seven Danish and 50 Finnish patients with familial adenomatous polyposis coli (FPC) were studied by panoramic tomography (PTG) of the mandible, which showed dental abnormalities in 17% of the cases. Eleven patients (11%) had supernumerary teeth and/or compound osteomas, and nine patients (9%) had impacted permanent teeth. The frequency of the dental anomalies was statistically significantly higher in FPC patients than in the normal population; it is therefore concluded that this dental abnormality should be included in the list of extracolonic manifestations that may occur in any FPC patient. The frequency of dental anomalies was higher in Finnish than in Danish patients, probably owing to a higher frequency of extracolonic manifestations in the Finnish series. DCompound osteomas; cysls; impacted teeth; odontomas; polyposis coli familiaris; supernumerary teeth

ISSN:0001-6357    

DOI:10.3109/00016358709094355

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor