Biomedical subjects

T Eger

Publications and source records attributed to T Eger.

23 records · Page 2Linked to original sources

PubMed1996

Ultrasonic determination of gingival thickness. Subject variation and influence of tooth type and clinical features.

The objectives of the present study were (I) to determine the validity and reliability of measuring gingival thickness (GTH) with a recently developed, commercially available ultrasonic device; (II) to measure GTH in relation to tooth type and age of proband; (III) to correlate GTH with varying forms of premolars, canines and incisors. Ultrasonic measurements were performed in 200 periodontally healthy, male probands representing 3 different age groups (20-25, 40-45, 55-60 years). In the maxilla, mean GTH varied between 0.9 mm (canines, 1st molars) and 1.3 mm (2nd molars). In the mandible respective mean values ranged between 0.8 mm (canines) and 1.5 mm (2nd molars). No differences in means and standard deviations (0.36-0.39 mm) were observed in different age groups. In order to correlate GTH with other clinical parameters and form of tooth, in 42 probands of the youngest age group, presenting with no attrition or abrasion, no artificial crown restorations and (following prophylaxis) no overt gingivitis and no periodontal probing depth in excess of 3 mm, detailed clinical measurements and stone model cast analyses were performed. By stepwise multiple linear regression analysis, 24% (p < 0.0001) of the variation of GTH was explained by probing depth, recession, width of gingiva and tooth type. The ratio of the width of the crown to its length was not included into the model. When performing analysis of covariance with the subject as factor, the model was improved, now explaining 41% of the variation of GTH. In this model, the influence of periodontal probing depth was decreased, and recession was not included. It was concluded that there are individual differences in GTH (i.e., different biotypes). However, thickness mainly depends on tooth type and is correlated with width of gingiva. There appears to be no association with shape and form of the tooth. Validity and reliability of measuring GTH with the ultrasonic device was found to be excellent.

Adult↗

PubMed1996

Potential diagnostic value of sampling oral mucosal surfaces for Actinobacillus actinomycetemcomitans in young adults.

Actinobacillus actinomycetemcomitans has been implicated in the pathogenesis of several forms of early onset and refractory adult periodontitis. Early diagnosis of colonization of the oral cavity might be of importance in order to initiate preventive measures. The aim of the present study was to determine the potential diagnostic value of oral mucosal and salivary tests to identify, among healthy young men with no or minor periodontal disease, individuals colonized by A. actinomycetemcomitans. Two hundred and one male recruits, 18-25 yr of age, took part in the present study. Mean values of periodontal parameters suggested only minor periodontal disease. Of the sites, 64.8 +/- 17.6% (mean +/- SD) had a periodontal probing depth (PPD) of 1 or 2 mm, only 1.6 +/- 2.9% deep sites of > or = 5 mm were detected. More than 1000 subgingival and extracrevicular samples were selectively cultivated for A. actinomycetemcomitans. The organism was isolated in 55 subjects (27%). The odds for presence of at least 1 deep site of 5 mm was increased by a factor 1.99 if A. actinomycetemcomitans, could be recovered. In identifying subjects colonized by A. actinomycetemcomitans, diagnostic test parameters sensitivity and predictive value for a negative test were 74.5 +/- 5.9% and 91.1 +/- 2.3%, respectively, for both saliva and dorsum of tongue samples. In contrast, pooled subgingival plaque from mesial surfaces of 1st molars was only 34.5 +/- 6.4% sensitive; the negative predictive value was 80.2 +/- 3.0%. The results point to a high diagnostic value of oral mucosal and especially saliva samples to identify young adult individuals colonized by A. actinomycetemcomitans.

Adolescent↗

PubMed1996

Natural distribution of oral Actinobacillus actinomycetemcomitans in young men with minimal periodontal disease.

A total of 1005 subgingival and extracrevicular samples from 201 male recruits, 18-25 yr old, were selectively cultivated for Actinobacillus actinomycetemcomitans. The organism was isolated in 55 subjects (27%); 9.5% of pooled subgingival plaque samples from first molars, 14% cheek mucosa, 20% dorsum of tongue and 20% saliva samples were culture-positive. In order to divide the study population into distinct clinical categories, cluster analysis was performed, based on previous caries experience, probing pocket depth categories, bleeding scores, visible plaque and calculus. Two clusters (n = 86 and n = 92, respectively) were identified with no or minimal periodontal disease (mean +/- standard deviation % of periodontal probing depth 1-2 mm 78.7 +/- 10.4% and 57.4 +/- 12.6%, respectively; virtually no periodontal probing/depth in excess of 4 mm) and a relatively low DMF-S (22 +/- 13). A third cluster (n = 22) had, in contrast, a high DMF-S (47.7 +/- 17.2) and a relatively high % of periodontal pockets of > or = 5 mm (5.9 +/- 5.2%). Prevalence of A. actinomycetemcomitans in this cluster was 41%, while the organism was found in 23% and 27% in the minimally diseased populations (p < 0.15). Whereas no heterogeneity of associations between subgingival and extracrevicular occurrence of the organism could be ascertained in different clusters, the organism was significantly more often identified in extracrevicular material, especially dorsum of tongue samples, compared with subgingival plaque (McNemar's chi2 = 12.45, p < 0.001). Multiple linear regression analysis revealed the number of A. actinomycetemcomitans positive samples as well as the % of sites bleeding on probing being positively associated with the % of sites with a probing pocket depth of > or = 5 mm (R2 = 0.345, p < 0.0001). The present large-scale investigation points to the wide distribution of this putative periodontopathogen in young individuals with minimal periodontal disease.

Adolescent↗

PubMed1995

Management of furcation-involved teeth. A retrospective analysis.

In the present study, data from more than 550 periodontally diseased patients with more than 1100 furcation invasions were retrospectively analysed. There were apparent differences in the distribution of different furcation degrees in patient populations treated by 2 differently experienced operators. However, treatment modality patterns were rather similar. Scaling during periodontal flap surgery was the most often performed treatment procedure in degree I (97-98%) and II (75-83%) involvements. About 44% of degree III involved teeth were extracted. In order to determine the influence of degree of furcation involvement, tooth type and operator variability on treatment modality, logistic regression analysis was applied. Degree of furcation involvement was an important indicator variable in all models. Scaling as a sole measure was mainly performed in relation to degree I of furcation involvement. With every increase in degree, the odds of scaling decreased by factor 12.7. The odds of root resection was upper 1st molars 46 x higher than in wisdom teeth or lower 2nd molars with the same degree of involvement, but only 3.3 x higher than in lower 1st molars. Tunnel preparation as well as regenerative procedures were mainly confirmed to lower molars. Operator variability was only introduced as a covariate in the extraction model. hence, despite of different operator skill and severity of periodontal disease in treated populations, decision for one or the other treatment modality seems to depend essentially on degree of furcation involvement as well as tooth type.

Adolescent↗

PubMed1994

Use of various genetic markers in differentiation of Mycobacterium bovis strains from animals and humans and for studying epidemiology of bovine tuberculosis.

One hundred fifty-three Mycobacterium bovis strains from cattle, various animal species from zoos and wild parks, and humans were analyzed for three different genetic markers for use in the epidemiology of bovine tuberculosis. M. bovis strains isolated from cattle were found to carry a single IS6110 element, whereas the majority of strains from other animals such as antelopes, monkeys, and seals harbored multiple IS6110 elements, suggesting that the reservoirs in cattle and wild animals are separated. Because the single IS6110 element in cattle strains is located at the same chromosomal position, strain differentiation by insertion sequence fingerprinting was hampered. Therefore, we investigated the usefulness of the direct repeat and polymorphic GC-rich repeat elements for strain differentiation. Both markers allowed sufficient strain discrimination for epidemiological purposes. Evidence is presented that in Argentina, most human M. bovis infections are due to transmission from cattle, whereas M. bovis infections among humans in the Netherlands are mainly contracted from animals other than cattle. Various outbreaks of M. bovis among animals and humans are described, including a small one which likely involved transmission from human to human.

Animals↗