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Thomas Dietrich

Publications and source records attributed to Thomas Dietrich.

34 records · Page 2Linked to original sources
PubMed2005

Associations between periodontal disease and systemic disease: evaluating the strength of the evidence.

Much work has been published on the association between periodontal disease and systemic disease, including original reports, narrative reviews, systematic reviews, and meta-analyses. Based on the existent work, one can assign an evidence level and grade, using standard evidence-based criteria, to the data available in the four major categories of medical outcomes studied: cardiovascular/cerebrovascular, pregnancy, pulmonary, and diabetes. We discuss methodologic and conceptual problems in the study of oral-systemic associations, focusing as an example on the association between periodontal disease and cardiovascular/cerebrovascular disease. We argue that the hierarchical ranking of studies by levels of evidence may be misleading. In particular, while randomized controlled trials (RCTs) are needed to determine the efficacy of periodontal treatment to reduce the risk of cardiovascular events, they may be of limited value in determining the etiologic role of periodontal disease on coronary heart disease and stroke. We discuss limitations of RCTs as well as the limitations of currently available data from epidemiologic studies, including study design and confounding and misclassification errors. We conclude that well-designed observational studies into the associations between periodontal disease and systemic disease need to remain an integral component of future research efforts in order to fully understand such associations.

Causality↗
PubMed2005

Zaleplon (Sonata) oral sedation for outpatient third molar extraction surgery.

Zalpelon was compared with triazolam for oral sedation in a third molar surgery model using a double-blind crossover design. Factors such as anxiolysis, amnesia, and quality of sedation were assessed. Of the 14 participants who completed the study, zaleplon sedation was found to be similar to triazolam sedation in all regards except that recovery from zaleplon was more rapid.

Acetamides↗
PubMed2004

Survival of glass fibre reinforced composite post restorations after 2 years-an observational clinical study.

OBJECTIVES: The aim of this study is to provide prospective clinical data for the survival of postendodontic reconstructions of teeth with varying degrees of hard tissue loss using tapered or parallel-sided post shapes. METHODS: Eighty-three patients got 105 glass fibre reinforced posts of tapered (Luscent Anchors, Dentatus, Sweden) and parallel-sided, serrated (FibreKor, Jeneric Pentron, USA) post shape. A dual curing hybrid composite Compolute (3M ESPE, Germany) was used as luting material, EBS-Multi (3M ESPE) as adhesive system and Clearfil Core (Kuraray, Japan) for core built-up. The restorations were followed for a minimum of 24 months. The statistical analysis was performed on a random sub-sample of one restoration per subject. The Fisher exact test was used to compare frequencies of failures after 12 and 24 month. A Kaplan-Meier-analysis was used to analyse time-to-failure in both groups. Differences of survival time between post types were tested with the log-rank test. RESULTS: 3.8% of the restorations failed after 12 month, 12.8% after 24 month, respectively. The main failure type observed was post fractures. All but one failed teeth could be restored. There was no difference in failure frequency between post types after 12 or 24 months. The log-rank test showed no differences in survival between the two types of post (p=0.37). CONCLUSION: Parallel-sided and tapered glass fibre posts result after 2 years of clinical service in an equal rate of survival.

Adolescent↗
PubMed2004

Network for auditory intrinsic alertness: a PET study.

Intrinsic alertness designates the internal (cognitive) control of wakefulness and arousal; typical tasks to assess optimal levels of intrinsic alertness are simple reaction time (RT) measurements without preceding warning stimuli. Until now, cerebral networks subserving alertness after visual and somatosensory stimulation have been reported. Studies concerning other intensity aspects of alertness like sustained attention and vigilance, on the other hand, have been performed in the auditory modality, too. In a 15O-butanol PET-activation study in 10 right-handed young healthy male volunteers an intrinsic alertness network was studied for the auditory modality. In contrast with a sensorimotor control condition we found an extended predominantly right-hemisphere network similar to those reported for other sensory modalities including frontal, cingular, inferior parietal, temporal and thalamic structures, when subjects waited for and rapidly responded to a 1000 Hz tone signal by pressing a response key with the right-hand thumb. There were, however, some differences in the topography of the frontal, temporal and thalamic activations between auditory and visual stimulation which are discussed with respect to similar results for auditory vigilance and auditory selective attention tasks reported in the literature.

Acoustic Stimulation↗
PubMed2004

The sensitivity and specificity of the OralCDx technique: evaluation of 103 cases.

In this study, we compared 103 OralCDx results with the histological findings of 96 clinical sites in 80 patients (33 females; 64.3+/-13.7 years and 47 males; 53.2+/-11.5 years). The histological findings were classified as follows: compatible with oral leukoplakia (OL; n = 60) or oral lichen planus (OLP; n = 17), both without dysplasia; dysplasia in OL or OLP (n = 9); and oral squamous cell carcinoma (OSCC; n = 17). There were seven (6.8%) specimens with an inadequate cell count. Overall, the sensitivity of the OralCDx technique to detect dysplasia and OSCC was 92.3% (95% CI: 74.9-99.1%), and the specificity was 94.3% (95% CI: 86.0-98.4%). The positive likelihood ratio (LR+) was 16.2 (95% CI: 6.2-42.1) and the negative likelihood ratio (LR-) was 0.08 (95% CI: 0.02-0.31). In conclusion, these figures are in agreement with previously published data and support the use of OralCDx as a screening tool of oral lesions, but further trials are still necessary.

Biopsy↗
PubMed2004

Clinical risk factors of oral leukoplakia in a representative sample of the US population.

Studies on the risk factors of oral leukoplakia (OL) are relatively scarce. The objectives of this paper are to assess the clinical risk factors of OL in a representative sample of the US population. Data from the oral mucosal tissue assessment and some other covariates of 15,811 participants in the US National Health and Nutrition Examination Survey (NHANES III) were included. The clinical definition of OL was applied according to the WHO criteria. Tobacco smoking was found as the strongest independent risk factor. The OR were 3.00 (0.77-11.8) for < or =10 cigarettes/day up to 6.01 (2.4-15.0) for >20 cigarettes/day. Diabetes, age and socio-economic status were found as independent predictors of OL. Alcohol consumption, race/ethnicity, years of education and BMI showed no independent association with OL. Females with a history of estrogen use were less likely to have OL with an OR of 0.34 (0.11-1.07). In conclusion, the role of diabetes and estrogen in the pathogenesis of OL should be further investigated.

Adult↗
PubMed2004

Association between serum concentrations of 25-hydroxyvitamin D3 and periodontal disease in the US population.

BACKGROUND: Periodontal disease (PD) is a common chronic inflammatory disease and an important risk factor for tooth loss. Vitamin D might affect periodontal disease risk via an effect on bone mineral density (BMD) or via immunomodulatory effects. OBJECTIVE: The objective was to evaluate whether serum 25-hydroxyvitamin D(3) [25(OH)D(3)] concentrations are associated with PD in the third National Health and Nutrition Examination Survey. DESIGN: We analyzed data on periodontal attachment loss (AL) and serum 25(OH)D(3) concentrations from 11 202 subjects aged > or =20 y. Mean AL was modeled in a multiple linear regression with quintile of serum 25(OH)D(3) concentration as an independent variable. The model was stratified by age and sex and was adjusted for age within age groups, race or ethnicity, smoking, diabetes, poverty income ratio, body mass index, estrogen use, and gingival bleeding. RESULTS: 25(OH)D(3) concentrations were significantly and inversely associated with AL in men and women aged > or =50 y. Compared with men in the highest 25(OH)D(3) quintile, those in the lowest quintile had a mean AL that was 0.39 mm (95% CI: 0.17, 0.60 mm) higher; in women, the difference in AL between the lowest and highest quintiles was 0.26 mm (0.09, 0.43 mm). In men and women younger than 50 y, there was no significant association between 25(OH)D(3) and AL. The BMD of the total femoral region was not associated with AL and did not mediate the association between 25(OH)D(3) and AL. CONCLUSIONS: Low serum 25(OH)D(3) concentrations may be associated with PD independently of BMD. Given the high prevalence of PD and vitamin D deficiency, these findings may have important public health implications.

Adult↗
PubMed2004

Higher 25-hydroxyvitamin D concentrations are associated with better lower-extremity function in both active and inactive persons aged > or =60 y.

BACKGROUND: Vitamin D may improve muscle strength through a highly specific nuclear receptor in muscle tissue. OBJECTIVES: We investigated whether there is an association between 25-hydroxyvitamin D [25(OH)D] concentrations and lower-extremity function in ambulatory older persons, whether that association differs by activity level, and, if so, whether there is an identifiable threshold in the association. DESIGN: The study was a population-based survey of the ambulatory US population aged 60 to > or =90 y (n = 4100). Lower-extremity function according to serum 25(OH)D concentrations was assessed by linear regression analyses and regression plots after control for activity level (inactive or active) and several other potential confounders. Separate analyses were performed for the timed 8-foot (ie, 2.4 m) walk test and a repeated sit-to-stand test. RESULTS: The 8-foot walk test compared subjects in the lowest and highest quintiles of 25(OH)D; the latter group had an average decrease of 0.27 s [95% CI: -0.44, -0.09 s (or 5.6%); P for trend < 0.001]. The sit-to-stand test compared subjects in the lowest and highest quintiles of 25(OH)D; the latter group had an average decrease of 0.67 s [95% CI: -1.11, -0.23 s (or 3.9%); P for trend = 0.017]. In the 25(OH)D reference range of 22.5-94 nmol/L, most of the improvement occurred in subjects with 25(OH)D concentrations between 22.5 and approximately 40 nmol/L, and further improvement was seen in the range of 40-94 nmol/L. Stratification by activity level showed no significant effect modification. CONCLUSION: In both active and inactive ambulatory persons aged > or =60 y, 25(OH)D concentrations between 40 and 94 nmol/L are associated with better musculoskeletal function in the lower extremities than are concentrations < 40 nmol/L.

Aged↗
PubMed2004

Keeping it short: a comparison of methods for brief picture presentation.

Research has shown that backward masking is a powerful tool for studying unconscious mental processes. Whereas studies have traditionally presented stimuli using cathode-ray tube (CRT) monitors or mechanical shutters together with slide projectors, recent studies (mainly in functional magnetic resonance imaging, fMRI) have begun to use methods based on liquid crystal displays (LCDs) and thin-film transistor (TFT) technology. However, because of differences in technology, all methods may not be equally suited for masking. When methods were compared for their accuracy in presenting pictures at short durations, LCD and TFT presentations had poor accuracy, but shutter and CRT presentations had better accuracy. Because CRTs interfere with the imaging process in fMRI, we recommend the use of mechanical shutters. However, our results may not generally apply to all displays, so we advise researchers to validate the presentation parameters of their displays. The procedure described here may be useful for that purpose.

Consciousness↗
PubMed2004

The effect of cigarette smoking on gingival bleeding.

BACKGROUND: The purpose of this study was to investigate the dose-dependent effect of cigarette smoking upon gingival bleeding on probing (BOP) in a large representative sample of the United States population (National Health and Nutrition Examination Survey III). METHODS: Weighted multiple logistic regression was used to model bleeding on probing of 141,967 mesio-buccal sites in 12,385 individuals with complete case records on all covariates. Adjustments were made for age, gender, race/ethnicity, number of missing teeth, tooth type/jaw, root caries, full crown coverage, socioeconomic status (poverty/income ratio), and survey characteristics. The model stratified by presence of calculus (CALC) and increased probing depth (PD > or = 4 mm). Generalized estimating equations were used to account for dependence of sites within subjects. RESULTS: Smoking had a strong suppressive effect on gingival bleeding. The effect was strongest in heavier smokers (> 10 cigarettes/day) and smallest in former smokers. In healthy sites (no CALC, PD < or = 3 mm), the odds ratio (OR) of bleeding for sites in heavier smokers compared to never-smokers was 0.56 (95% CI: 0.45-0.70). Sites with CALC and/or PD > or = 4 mm were more likely to bleed in never-smokers (OR: 5.7; 95% CI: 4.3-7.6). This relationship was less evident among heavier smokers (OR: 1.3; 95% CI: 0.8-1.9). The effect of smoking did not differ between maxillary and mandibular molars, premolars, or incisors. CONCLUSION: Smoking exerts a strong, chronic, and dose-dependent suppressive effect on gingival bleeding on probing.

Adolescent↗
PubMed2003

Low prevalence of oral leukoplakia in a representative sample of the US population.

Recent studies reported a tendency towards a lower prevalence of oral leukoplakia (OL), compared with the past. To assess the prevalence of OL in a representative sample of the US population, data from the oral mucosal tissue assessment and some other covariates of 16128 participants in the US National Health and Nutrition Examination Survey (NHANES III) were included. The clinical definition of OL was applied according to the WHO criteria. The weighted prevalence estimates of OL were 0.66+/-0.14% in males, 0.21+/-0.05% in females and 0.42+/-0.08% in total. The age peaks were at 40-49 years in males and at >or=70 years in females. The prevalence estimates were 0.37% for homogeneous OL and 0.06% for non-homogeneous OL. Gingiva (38.8%) and buccal mucosa (30.9%) were the most frequent locations. Compared to previous studies in the USA, a substantial decline of the prevalence of OL was shown.

Adult↗
PubMed2003

Periapical and periodontal healing after osseous grafting and guided tissue regeneration treatment of apicomarginal defects in periradicular surgery: results after 12 months.

OBJECTIVE: The aim of the present study was to evaluate the periapical and periodontal healing of apicomarginal defects 12 months after periradicular surgery and guided tissue regeneration in a series of consecutively treated patients. STUDY DESIGN: Patients with apicomarginal defects who were referred for periradicular surgery were included. Apicomarginal defects were grafted with Bio-Oss bone mineral and covered with a Bio-Gide membrane. Periodontal probing depths (PPDs) and relative attachment levels were measured preoperatively and 12 months postoperatively with a manual force-controlled probe. Periapical healing was assessed clinically and radiographically. RESULTS: Of the 23 defects in 22 patients for whom follow-up data were available, 19 were considered clinically and radiographically successful, 2 were doubtful, and 2 were failures. Overall, the baseline median PPD decreased from 9.0 mm to 3.0 mm, corresponding to a median relative attachment level gain of 2.8 mm. In the case of periodontic-endodontic lesions, the median baseline PPD decreased from 9.8 mm to 4.0 mm, corresponding to a median relative attachment level gain of 4.2 mm. Defects that involved a proximal root surface had a significantly higher residual PPD than did defects not involving a proximal root surface. CONCLUSIONS: Guided tissue regeneration treatment of apicomarginal defects yields good results in terms of periapical and periodontal healing after 12 months and should be considered as an adjunct to periradicular surgery in such cases.

Adolescent↗
PubMed2002

Blood contamination and dentin bonding--effect of anticoagulant in laboratory studies.

OBJECTIVE: To investigate the influence of heparinized blood vs. native blood on the marginal adaptation of dentin bonded composite resin restorations. METHODS: Cylindrical dentin cavities were prepared in 40 extracted human incisors. After acid-etching four groups (n=10) were contaminated with either fresh capillary blood (FCB), heparinized venous blood (HPB), saline (SAL) or heparinized saline (HPS) and bonded and filled with Scotchbond 1/Z 100. After water storage for 21 days and thermocycling (2000 x, 5-55 degrees C), replicas were produced for evaluation of marginal adaptation by means of quantitative marginal analysis in the SEM. Statistical analysis was performed with the Kruskal-Wallis-test and the Bonferroni correction for multiple comparisons at p<0.05. RESULTS: There were no differences between groups SAL, HPS and HPB. Contamination with fresh capillary blood resulted in significantly higher amounts of marginal openings compared to all other groups. SIGNIFICANCE: Freshly drawn blood has to be used for blood contamination experiments in laboratory studies.

Acid Etching, Dental↗
PubMed2002

White blood cell count in generalized aggressive periodontitis after non-surgical therapy.

BACKGROUND: Periodontal bacteria are known to invade the systemic circulation. Chronic low-level bacteremia and a systemic inflammatory response have been suggested as a pathogenetic link between periodontal disease and atherosclerosis. The purpose of this study was to examine the systemic effect of a non-surgical therapy on white blood cell count (WBC count) and differential blood count in smoking and non-smoking generalized aggressive periodontitis (GAP) patients. METHODS: 27 adult periodontitis patients (13 smokers and 14 non-smokers) with previously untreated GAP were subjected to 3 sessions of oral hygiene procedure. Afterwards, the patients were treated by scaling and root planing under local anaesthesia. Periodontal examinations were performed after supragingival pretreatment and three months after subgingival therapy. Pocket probing depth (PPD) and relative attachment level (RAL) were measured with Florida probe and disc probe. Accompanying clinical evaluation venous blood samples were taken to analyse the WBC counts and differential blood counts. For statistical analysis non-parametric tests were utilized. RESULTS: No clinical or demographic differences were found between smokers (n=13) and non-smokers (n=14). PPD, bleeding on probing (BoP) and suppuration improved significantly after therapy both in smokers and non-smokers. Following periodontal treatment WBC counts, neutrophil and platelet counts decreased significantly in non-smokers (p< or =0.004), while in smokers only platelet counts were significantly reduced (p=0.006). Non-smokers showed a significantly higher reduction of WBC counts (p=0.005) and neutrophils (p=0.001) compared to smokers. CONCLUSION: The results indicate that a therapeutical intervention may have a systemic effect on the blood count in GAP patients. This effect seems to differ between smokers and non-smokers.

Adult↗
PubMed2002

Apicomarginal defects in periradicular surgery: classification and diagnostic aspects.

The prognosis of periradicular surgery is affected by the amount and location of bone loss. Apicomarginal defects are localized bony defects encompassing the total root length, and periradicular surgery on these teeth is associated with a lower success rate. This paper reviews the etiology, pathogenesis, and morphology of apicomarginal defects as encountered in periradicular surgery on the basis of a series of 24 consecutively treated patients. Periodontal data were recorded before surgery in all patients, and apicomarginal defects were diagnosed after flap reflection or, if applicable, apicoectomy. On the basis of the findings in these cases and on theoretic considerations, a classification system for apicomarginal defects with potential therapeutic and prognostic implications is presented and several criteria for differential diagnosis are discussed.

Adolescent↗