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Objective: Monosynaptically cortically innervated α‐motoneurons are early and strongly involved in amyotrophic lateral sclerosis (ALS). Consequently, the muscles that receive the strongest direct corticomotoneuronal input are the clinically most affected. To objectify this concept in vivo through morphological image correlates, whole‐body magnetic resonance imaging (MRI) with muscle signal analysis was performed in patients with ALS compared to healthy controls. Methods: Modified Dixon‐based whole‐body MRI was acquired in patients with ALS (n = 33) and matched healthy controls (n = 30). Manual labeling of limb muscle MRI was performed, and a specific subset of nine muscles, selected as pairs of muscle groups with different corticomotoneuronal input, was analyzed per subject based on their volume, fat fraction, and functional remaining muscle area (fRMA). Results: Statistical analysis of 978 muscles in total revealed significantly decreased volumes, decreased fRMA, and increased fat fraction in the muscles of patients with ALS compared to controls. The clinical degree of pareses of directly innervated muscles was significantly worse than that of less directly innervated muscles in each comparison. The muscles receiving stronger direct corticomotoneuronal input showed more pronounced morphological involvement compared to those with less monosynaptic corticomotoneuronal input (fRMA, significant in three pairwise comparisons). Interpretation: In conclusion, whole‐body MRI‐based muscle analysis provided additional evidence for a characteristic pattern of pareses in ALS. This technical approach (parameterization and quantification of muscle alterations from MRI) to patients with ALS could pave the way for the future establishment of a diagnostic algorithm of muscle MRI for ALS and may serve as a biomarker. [ABSTRACT FROM AUTHOR]

Background: The underlying neuropathological process of amyotrophic lateral sclerosis (ALS) can be classified in a four‐stage sequential pTDP‐43 cerebral propagation scheme. Using diffusion tensor imaging (DTI), in vivo imaging of these stages has already been shown to be feasible for the specific corticoefferent tract systems. Because both cognitive and oculomotor dysfunctions are associated with microstructural changes at the brain level in ALS, a cognitive and an oculomotor staging classification were developed, respectively. The association of these different in vivo staging schemes has not been attempted to date. Methods: A total of 245 patients with ALS underwent DTI, video‐oculography, and cognitive testing using Edinburgh Cognitive and Behavioral ALS Screen (ECAS). A set of tract‐related diffusion metrics, cognitive, and oculomotor parameters was selected for further analysis. Hierarchical and k‐means clustering algorithms were used to obtain an optimal cluster solution. Results: According to cluster analysis, differentiation of patients with ALS into four clusters resulted: Cluster A showed the highest fractional anisotropy (FA) values and thereby the best performances in executive oculomotor tasks and cognitive tests, whereas cluster D showed the lowest FA values, the lowest ECAS scores, and the worst executive oculomotor performance across all clusters. Clusters B and C showed intermediate results regarding parameter values. Discussion: In a multimodal dataset of technical assessments of brain structure and function in ALS, an artificial intelligence‐based cluster analysis showed high congruence of DTI, executive oculomotor function, and neuropsychological performance for mapping in vivo correlates of neuropathological spreading. [ABSTRACT FROM AUTHOR]

Objective: This study provides a comprehensive overview of the associations of five adipokines (adiponectin, chemerin, galectin-3, leptin, and resistin) with fat deposits, behavioral risk factors, and metabolic phenotypes.Methods: Using multivariable linear and logistic regression models, cross-sectional data from 4,116 participants of the population-based Study of Health in Pomerania were analyzed.Results: Participants with obesity showed higher chemerin, galectin-3, and leptin but showed lower adiponectin concentrations. Independently of other fat compounds, liver fat content, visceral adipose tissue, and subcutaneous adipose tissue (SAT) were inversely associated with adiponectin. Independent positive associations of liver fat content and SAT with chemerin as well as of SAT with galectin-3 and leptin were observed. Physically inactive participants had higher chemerin and leptin concentrations. Smokers had higher chemerin and galectin-3 as well as lower leptin. Alcohol consumption was associated with adiponectin (positive) and resistin (inverse). All adipokines were associated with at least one lipid marker. Associations with glucose metabolism were seen for adiponectin, chemerin, galectin-3, and leptin.Conclusions: High adiponectin concentrations were related to favorable metabolic conditions, whereas high chemerin, galectin-3, and leptin were associated with an unfavorable metabolic profile. High leptin seems to be primarily indicative of obesity, whereas high adiponectin and chemerin are associated with a broader range of metabolic phenotypes. [ABSTRACT FROM AUTHOR]

Background: The pathophysiology of the hypothalamic involvement in Parkinson's disease (PD) is not well understood. The objective of this study was the quantification of hypothalamic volumes in vivo in PD.Methods: High-resolution T1 -weighted magnetic resonance imaging (MRI) data from 232 individuals with PD and 130 healthy non-PD individuals were used for quantification of the hypothalamic volumes.Results: The hypothalamus in PD was not atrophied, as indicated by volumetric analyses in the prospectively collected subcohort (30 PD, V = 921 ± 78 mm3 vs 30 non-PD, V = 917 ± 67 mm3 ; P = 0.850) and validated in a large cohort (202 PD, V = 925 ± 88 mm3 vs 100 non-PD, V = 932 ± 114 mm3 ; P = 0.602).Conclusions: Hypothalamic involvement in PD as shown by a large body of histopathological evidence does not appear to be detectable by MRI-based volumetric quantification. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

We investigated the brain atrophy distribution pattern and rate of regional atrophy change in Parkinson's disease (PD) in association with the cognitive status to identify the morphological characteristics of conversion to mild cognitive impairment (MCI) and dementia (PDD). T1‐weighted longitudinal 3T MRI data (up to four follow‐up assessments) from neuropsychologically well‐characterized advanced PD patients (n = 172, 8.9 years disease duration) and healthy elderly controls (n = 85) enrolled in the LANDSCAPE study were longitudinally analyzed using a linear mixed effect model and atlas‐based volumetry and cortical thickness measures. At baseline, PD patients presented with cerebral atrophy and cortical thinning including striatum, temporoparietal regions, and primary/premotor cortex. The atrophy was already observed in "cognitively normal" PD patients (PD‐N) and was considerably more pronounced in cognitively impaired PD patients. Linear mixed effect modeling revealed almost similar rates of atrophy change in PD and controls. The group comparison at baseline between those PD‐N whose cognitive performance remained stable (n = 42) and those PD‐N patients who converted to MCI/PDD ("converter" cPD‐N, n = 26) indicated suggested cortical thinning in the anterior cingulate cortex in cPD‐N patients which was correlated with cognitive performance. Our results suggest that cortical brain atrophy has been already expanded in advanced PD patients without overt cognitive deficits while atrophy progression in late disease did not differ from "normal" aging regardless of the cognitive status. It appears that cortical atrophy begins early and progresses already in the initial disease stages emphasizing the need for therapeutic interventions already at disease onset. [ABSTRACT FROM AUTHOR]

Background and objective: The aim of this study was to investigate the influence of smoking on the site‐specific association between bleeding on gingival probing and supragingival plaque and to assess whether this differs in different regions of the dentition. Methods: Data from a representative sample of 1911 adults (20‐79 years old) in Northern Norway were analyzed. Periodontal examinations consisted of full‐mouth recordings of periodontal probing depth (PD), bleeding on probing (BOP), and presence of supragingival plaque. Smoking status and background characteristics were self‐reported by questionnaire. The association between plaque and BOP was assessed in several three‐level (subject, tooth, and site) random intercept logistic regression models adjusted for PD, smoking status, socioeconomic factors, and body mass index. In a further model, it was assessed whether the association between supragingival plaque and BOP differed in different parts of the dentition. Results: For plaque‐free sites, bleeding tendency was lower in smokers, the odds ratio (OR) was 0.773 with a 95% confidence interval of 0.678‐0.881 as compared to non‐smokers (OR: 1; ref., P <.001). The odds of BOP at plaque‐covered sites in non‐smokers were increased twofold (OR: 2.117; 2.059‐2.177). Albeit bleeding tendency was slightly increased in plaque‐covered sites in smokers, it was considerably lower as compared to plaque‐covered sites in non‐smokers (OR: 1.459; 1.282‐1.662, P <.001). Smoking ≥ 20 pack‐years further attenuated the association. In smokers, the odds of BOP were reduced in all parts of the dentition, lower and upper anterior and posterior teeth (χ(4)2= 32.043, P <.001). When restricting the data to younger adults (20‐34 year old), smoking had only a slight effect on the association between plaque and BOP. For plaque‐free and plaque‐covered sites, differences in ORs were not statistically noticeable (P =.221 and P =.235, respectively). Conclusions: Smoking considerably attenuates the site‐specific association between plaque and BOP with a dose‐dependent effect. The effect of smoking did not differ across tooth types. [ABSTRACT FROM AUTHOR]

Objective: Heterozygous SHANK3 mutations or partial deletions of the long arm of chromosome 22, also known as Phelan–McDermid syndrome, result in a syndromic form of the autism spectrum as well as in global developmental delay, intellectual disability, and several neuropsychiatric comorbidities. The exact pathophysiological mechanisms underlying the disease are still far from being deciphered but studies of SHANK3 models have contributed to the understanding of how the loss of the synaptic protein SHANK3 affects neuronal function. Methods and results: Diffusion tensor imaging‐based and automatic volumetric brain mapping were performed in 12 SHANK3‐deficient participants (mean age 19 ± 15 years) versus 14 age‐ and gender‐matched controls (mean age 29 ± 5 years). Using whole brain–based spatial statistics, we observed a highly significant pattern of white matter alterations in participants with SHANK3 mutations with focus on the long association fiber tracts, particularly the uncinate tract and the inferior fronto‐occipital fasciculus. In contrast, only subtle gray matter volumetric abnormalities were detectable. In a back‐translational approach, we observed similar white matter alterations in heterozygous isoform–specific Shank3 knockout (KO) mice. Here, in the baseline data sets, the comparison of Shank3 heterozygous KO vs wildtype showed significant fractional anisotropy reduction of the long fiber tract systems in the KO model. The multiparametric Magnetic Resonance Imaging (MRI) analysis by DTI and volumetry demonstrated a pathology pattern with severe white matter alterations and only subtle gray matter changes in the animal model. Interpretation: In summary, these translational data provide strong evidence that the SHANK3‐deficiency–associated pathomechanism presents predominantly with a white matter disease. Further studies should concentrate on the role of SHANK3 during early axonal pathfinding/wiring and in myelin formation. [ABSTRACT FROM AUTHOR]

Background: The topography of functional network changes in progressive supranuclear palsy can be mapped by intrinsic functional connectivity MRI. The objective of this study was to study functional connectivity and its clinical and behavioral correlates in dedicated networks comprising the cognition-related default mode and the motor and midbrain functional networks in patients with PSP.Methods: Whole-brain-based "resting-state" functional MRI and high-resolution T1-weighted magnetic resonance imaging data together with neuropsychological and video-oculographic data from 34 PSP patients (22 with Richardson subtype and 12 with parkinsonian subtype) and 35 matched healthy controls were subjected to network-based functional connectivity and voxel-based morphometry analysis.Results: After correction for global patterns of brain atrophy, the group comparison between PSP patients and controls revealed significantly decreased functional connectivity (P < 0.05, corrected) in the prefrontal cortex, which was significantly correlated with cognitive performance (P = 0.006). Of note, midbrain network connectivity in PSP patients showed increased connectivity with the thalamus, on the one hand, whereas, on the other hand, lower functional connectivity within the midbrain was significantly correlated with vertical gaze impairment, as quantified by video-oculography (P = 0.004). PSP Richardson subtype showed significantly increased functional motor network connectivity with the medial prefrontal gyrus.Conclusions: PSP-associated neurodegeneration was attributed to both decreased and increased functional connectivity. Decreasing functional connectivity was associated with worse behavioral performance (ie, dementia severity and gaze palsy), whereas the pattern of increased functional connectivity may be a potential adaptive mechanism. © 2017 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Objective: Association studies of selenoprotein P (SELENOP) with cardiometabolic traits in humans are relatively scarce and, in part, conflicting. A general population sample from Northern Germany was evaluated for cross-sectional associations of circulating SELENOP concentrations with metabolic syndrome (MetS), total volumes of MRI-determined visceral (VAT) and subcutaneous (SAT) abdominal adipose tissue, liver signal intensity, and fatty liver disease (FLD).Methods: Nine hundred and five participants received comprehensive clinical and molecular phenotyping along with measurement of serum SELENOP; 584 individuals received MRI.Results: Multivariable-adjusted restricted cubic regression splines displayed statistically significant inverse relations of SELENOP levels with MetS, VAT, and SAT (P < 0.0001 for all). Compared with the second quartile of SELENOP distribution, the MetS odds ratios for the first, third, and fourth quartiles were 1.62 (95% confidence interval [CI]: 1.08-2.43), 0.85 (95% CI: 0.57-1.26), and 0.41 (95% CI: 0.27-0.62), respectively. Furthermore, participants in the second, third, and fourth SELENOP quartiles had significantly lower VAT and SAT volumes as compared to those in the first biomarker quartile. A J-shaped relation was observed for SELENOP levels and liver signal intensity/FLD (P = 0.01).Conclusions: The findings suggest inverse associations of circulating SELENOP concentrations with several metabolic traits, to be further investigated in longitudinal studies. [ABSTRACT FROM AUTHOR]

For decades, Aggregatibacter actinomycetemcomitans has been considered the most likely etiologic agent in aggressive periodontitis. Implementation of DNA-based microbiologic methodologies has considerably improved our understanding of the composition of subgingival biofilms, and advanced open-ended molecular techniques even allow for genome mapping of the whole bacterial spectrum in a sample and characterization of both the cultivable and not-yet-cultivable microbiota associated with periodontal health and disease. Currently, A. actinomycetemcomitans is regarded as a minor component of the resident oral microbiota and as an opportunistic pathogen in some individuals. Its specific JP2 clone, however, shows properties of a true exogenous pathogen and has an important role in the development of aggressive periodontitis in certain populations. Still, limited data exist on the impact of other microbes specifically in aggressive periodontitis. Despite a wide heterogeneity of bacteria, especially in subgingival samples collected from patients, bacteria of the red complex in particular, and those of the orange complex, are considered as potential pathogens in generalized aggressive periodontitis. These types of bacterial findings closely resemble those found for chronic periodontitis, representing a mixed polymicrobial infection without a clear association with any specific microorganism. In aggressive periodontitis, the role of novel and not-yet-cultivable bacteria has not yet been elucidated. There are geographic and ethnic differences in the carriage of periodontitis-associated microorganisms, and they need to be taken into account when comparing study reports on periodontal microbiology in different study populations. In the present review, we provide an overview on the colonization of potential periodontal pathogens in childhood and adolescence, and on specific microorganisms that have been suspected for their role in the initiation and progression of aggressive forms of periodontal disease. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: Glutaric aciduria type II (GAII) is a rare autosomal recessive disorder with variable clinical course. The disorder is caused by a defect in the mitochondrial electron transfer flavoprotein or the electron transfer flavoprotein dehydrogenase (ETFDH). Methods: We performed clinical characterization, brain and whole body MRI, muscle histopathology, and genetic analysis of the ETFDH gene in a young woman. Results: She presented with rhabdomyolysis and severe quadriparesis. We identified a novel homozygous missense mutation in ETFDH (c.1544G>T, p.Ser515Ile). Body fat MRI revealed a large amount of subcutaneous fat but no increase in visceral fat despite steatosis of liver and muscle. Diffusion tensor imaging (DTI) of cerebral MRI revealed reduced directionality of the white matter tracts. Histopathological findings showed lipid storage myopathy. Conclusions: In this study, we highlight diagnostic clues and body fat MRI in this rare metabolic disorder. Muscle Nerve 49:446-450, 2013 [ABSTRACT FROM AUTHOR]

INTRODUCTION In order to obtain detailed information on disease-associated changes in the integrity of cerebral white matter (WM), complementary image analysis (CIA) was applied to patients with amyotrophic lateral sclerosis (ALS) and controls. METHODS Both diffusion tensor imaging and T1-weighted 3-dimensional data were analyzed with respect to WM microstructure and T1 signal intensity alterations, respectively, in a sample of 19 ALS patients. Covariate information was added in the form of clinical parameters. All results were obtained in one common analysis software environment (Tensor Imaging and Fiber Tracking). RESULTS Complementary analysis and display were performed for WM directionality and structure. Significant WM differences between ALS patients and controls were observed both in the motor system, that is, the bilateral corticospinal tracts, and in extramotor brain areas, in part correlating with clinical parameters. The performance of all analyses in one software environment enabled the synopsis of results obtained from various analyses. DISCUSSION/CONCLUSION Within the application of CIA to a neurodegenerative disease for the whole brainbased analysis of WM alterations together with clinical characteristics, it could be demonstrated that ALS was associated with WM changes within and outside the motor system. [ABSTRACT FROM AUTHOR]

Different motor neuron disorders (MND s) are mainly defined by the clinical presentation based on the predominance of upper or lower motor neuron impairment and the course of the disease. Magnetic resonance imaging (MRI) mostly serves as a tool to exclude other pathologies, but novel approaches such as diffusion tensor imaging (DTI) have begun to add information on the underlying pathophysiological processes of these disorders in vivo. The present study was designed to investigate three different rare MNDs, i.e., primary lateral sclerosis (PLS, N = 25), hereditary spastic paraparesis (HSP, N = 24), and X-linked spinobulbar muscular atrophy (X-SBMA, N = 20), by use of whole-brain-based DTI analysis in comparison with matched controls. This analysis of white matter (WM) impairment revealed widespread and characteristic patterns of alterations within the motor system with a predominant deterioration of the corticospinal tract (CST) in HSP and PLS patients according to the clinical presentation and also in patients with X-SBMA to a lesser degree, but also WM changes in projection s to the limbic system and within distinct areas of the corpus callosum (CC), the latter both for HSP and PLS. In summary, DTI was able to define a characteristic WM pathoanatomy in motor and extra-motor brain areas, such as the CC and the limbic projectional system, for different MNDs via whole brain-based FA assessment and quantitative fiber tracking. Future advanced MRI-based investigations might help to provide a fingerprint-identification of MNDs. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Background: We previously reported a high prevalence of a combination of alleles 2 at positions interleukin (IL)-IA-889 and IL-IB+3954 in an Arabic population with gingivitis. In a steady state, the proportion of sites with bleeding on probing (BOP) was consistently reduced. The aim of the present study is to expand this observation by considering the site level. Methods: Fifty healthy non-smoking volunteers, 19 to 28 years of age, participated in this study. Clinical examinations included probing depth, BOP, plaque index (PI), and calculus. Examinations were repeated after 2 and 4 weeks, and subjects were advised not to change oral hygiene habits. Polymorphisms in the IL-1 gene cluster were assessed using a reverse hybridization assay. Results: Twenty-six subjects (52%) carried alleles 2 at positions IL-IA-889 and IL-1B+3954 and were designated genotype positive. In multivariate multilevel models of BOP, bleeding tendency in subjects with positive IL-1 genotype was only reduced at sites with PI 0 (odds ratio of 0.98, 0.65, and 0.56 at baseline and 2 and 4 weeks, respectively; χ² (3) = 11.946; P = 0.008) or 1 (χ² (3) = 6.027; P = 0.110). A decreased bleeding tendency at certain tooth types in subjects who were IL-1 positive was largely related to the relative cleanliness of these areas. Random parts of the models revealed very low biserial correlations of 0.13 to 0.15 at the site level, whereas correlations were considerably higher (0.76 to 0.83) at the subject level. Conclusion: Multilevel modeling of site-specific data yielded new information about the influence of the IL-1 genotype in plaque-induced gingivitis. J Periodontol 2010;81:52-61. [ABSTRACT FROM AUTHOR]

There is lack of data on the suitability of animal cadaver models for teaching purposes in dentistry. Here, we describe a model suitable for training for several periodontal surgical methods. Mandibles of freshly slaughtered Australian adult sheep and lambs were examined. Periodontal probing depths (PPDs) were measured at six sites of every tooth present. The following surgical techniques were critically analyzed: access flap with interrupted, continuous sutures; apically repositioned flap with periosteal sutures; coronally advanced flap with sling suture; gingivectomy; and distal wedge procedure. Probing depths were highest in the buccal furcation area of 1st and 2nd molars, where deep intrabony lesions were present in certain samples from adult sheep. Another area of increased probing depth was lingual to canines and incisors. Here, a pronounced lower dental pad of fibrous tissue was present. In this area, gingivectomy could always be accomplished. Fibrous tissue was also found distal to the most posterior molar, where the distal wedge procedure could be exercised. Access flaps and apically repositioned flaps could be performed particularly at premolars. Here, interrupted or continuous sutures were possible. Because of tight interdental contact areas, needle insertion was difficult at molars. After periosteal dissection, labial flaps at anterior teeth could easily be advanced coronally and sutured with sling sutures. Because of the teeth's dimensions and tight contact areas, simulation of more advanced techniques such as papilla preservation flaps was not possible. The sheep mandible seems to be a feasible training model for the demonstration and exercise of various periodontal surgical techniques for the treatment of periodontitis. [ABSTRACT FROM AUTHOR]

Abstract Background/aims: Whereas accumulation of dentogingival plaque inevitably leads to inflammatory reactions in the adjacent gingival tissue, there is limited information with regard to factors influencing naturally occurring fluctuation between gingival health and disease. The major aims of the present study were to investigate site-specific associations between plaque and gingivitis as well as transition dynamics of naturally occurring gingivitis in smoking and non-smoking young adults. Methods: 65 systemically healthy young adults, 19 to 30 years old, participated. 33 volunteers smoked at least 20 cigarettes per day, whereas 32 subjects were non-smokers. Clinical periodontal conditions were assessed four times within a time period of 6 months. An ecological approach in data analysis as well as site-specific analyses considering the correlated structure of data were performed. Results: At the outset and after 6 months, smokers had significantly more supragingival plaque than non-smokers. At the final examination, bleeding upon probing as well as calculus were more prevalent in smokers. A site-by-site analysis revealed that smokers tended to have a weaker association between supragingival plaque and bleeding on probing than non-smokers (median Mantel-Haenszel's common odds ratio 1.91 vs. 2.89, p =0.07). Multiple logistic regression analyses adjusted for periodontal probing depth, plaque and calculus identified smoking status to significantly increase the risk for the first transition of non-bleeding to bleeding upon probing by 86% (p <0.01). In contrast, recovery of bleeding sites was positively influenced by female gender, but not smoking. Conclusions: In multivariate analyses adjusted for probing depth, plaque and calculus, smokers appeared to be at higher risk for the transition from non-bleeding to bleeding on probing. Weaker associations between plaque and naturally occurring gingivitis in smokers may have important consequences for preventive... [ABSTRACT FROM AUTHOR]

Abstract Background/aims: Smoking is a major risk factor for destructive periodontal disease. There is limited information with regard to effects of smoking in subjects with minimal periodontal destruction. The aim of the present investigation was to assess the development of gingival recession in young adult smokers and non-smokers. Methods: 61 systemically healthy young adults, 19 to 30 years of age completed the final examination. 30 volunteers smoked at least 20 cigarettes per day, whereas 31 subjects were non-smokers. Clinical periodontal conditions were assessed 4× within a time period of 6 months. Site-specific analyses considering the correlated structure of data were performed. Results: At the outset, 50% of subjects presented with gingival recession at 1 or more sites. There was no significant difference in the prevalence of gingival recession between non-smokers and smokers. Severe recession in excess of 2 mm affected about 23% non-smokers but only 7% smokers. Some further gingival recession developed during the 6-month observation period. In a multivariate logistic regression analysis, the risk for recession development appeared not to be influenced by smoking status after adjusting for periodontal probing depth, recession at baseline, tooth brushing frequency, gender, jaw, tooth type and site. Conclusions: Present data did not support the hypothesis that smokers are at an increased risk for the development of gingival recession. [ABSTRACT FROM AUTHOR]

AbstractAims: The aim of the present investigation was to study thickness of masticatory mucosa and gingival width in subjects with different periodontal phenotypes. Methods: Periodontal phenotypes were defined with the aid of cluster analysis of standardised parameters including mean gingival thickness and width as well as ratio of crown width to its length at maxillary canines, lateral and central incisors of 40 young adults with healthy periodontal conditions. Results: 3 groupings could be observed. Clusters A1 and A2 comprised 75% of all subjects. They were characterised by thin gingiva and a slender tooth form. Clusters A1 and A2 were differentiated by gingival width. Cluster B comprised 11 subjects with relatively thick and wide gingiva and a quadratic tooth shape. In general, characteristics of the frontal sextant in the maxilla were also found in other parts of the dentition. Thus, mean thickness of masticatory mucosa as well as gingival width and crown form differed significantly among clusters. In addition, cluster B subjects had a significantly greater mean periodontal probing depth. Multiple linear regression analysis was employed to identify significant factors influencing palatal mucosal thickness. Women had considerably thinner palatal mucosa than men. Furthermore, cluster affiliation had a significant influence on thickness of palatal mucosa. Thickest tissue was found in the premolar region, whereas the mucosa over the root prominence of the first molar represented an anatomical barrier for graft harvesting. Conclusions: Thickness of masticatory mucosa strongly depends on gender and the periodontal phenotype. [ABSTRACT FROM AUTHOR]

Background: The aim of the present study was to assess thickness of all parts of the masticatory mucosa by using an ultrasonic measuring device. Methods: A total of 40 periodontally healthy subjects, 19 to 30 years old, took part. Thickness of masticatory mucosa was measured at a maximum of 149 sites in each proband. Results: Female volunteers had significantly thinner mean masticatory mucosa than males (p<0.01). Mean thickness of facial gingiva ranged between 0.7 mm at canines in the maxilla and central incisors in the mandible and 2.3 mm at 3rd molars in the mandible. In the mandible, thickness of lingual gingiva ranged between 0.9 mm at lateral incisors and 2.3 mm at 3rd molars. Interdental gingiva ranged between 1.0 mm 2.1 mm. With 3 mm or more, on average, palatal masticatory mucosa was thickest in the 3rd molar region and at 2nd premolars at more central locations. 2 regions with comparatively thin palatal mucosa of about 2 mm were identified, namely (i) at central and lateral incisors and (ii) at the prominence of the palatal roots of 1st and 2nd molars. The thickest tissue with more than 4 mm, on average, was observed in the tuberosity and retromolar regions. Conclusions: Considerable intra- as well as interindividual variation of thickness of masticatory mucosa could be observed. According to differences in thickness of facial and interdental gingiva, it appears that lining is also an important function of the gingiva in reducing and smoothing the pronounced convexities of the dento-alveolar, i.e., skeletal, complex. [ABSTRACT FROM AUTHOR]

AbstractBackground: So far, the clinical effects of the placement of a resorbable membrane for guided tissue regeneration have not been studied in humans in great detail. The dynamics of the resorptive processes, in particular, appear to be rather speculative. In the present longitudinal study, specific alterations of the dimensions of the dentogingival mucosa were explored after surgical root coverage by using a bioresorbable membrane and a coronally-repositioned flap. Methods: The study population consisted of 14 patients with a total of 31 predominantly shallow, Miller class I, II or III recessions. The thickness of the masticatory and lining mucosa before and after surgical intervention was measured with an ultrasonic device. Results: Mean (±sd) recession depth and width were 2.85±1.29 and 4.46±1.14 mm, respectively. After 12 months, 51±29% of the recession depth (p<0.001) and 13±35% of its width (n.s.) were covered. Root coverage seems to be rather defect-type sensitive with best results obtained at canines with relatively shallow recessions. Mucosal thickness was considerably increased after surgery with a gradual decrease during the following 9 months. Thus, thickness of the marginal tissue rose from 0.82±0.27 mm to 1.49±0.54 mm 3 months after placement of the membrane (p<0.001). After 12 months, a mean thickness of 1.03±0.40 mm was observed (p<0.001). Even more pronounced alterations were noted for the alveolar lining mucosa with a threefold increase of thickness 3 months after surgery and a gradual decrease to about 1 mm after 12 months. Conclusions: The present results point to the considerable space making capacity of the bioresorbable membrane which probably allows for the ingrowth of a granulation tissue derived from the underlying structures. The gradual decline in mucosal thickness between months 6 and 9 after surgery may be paralleled by the maturation of the granulation tissue while complete resorption of the membrane had been accomplished. [ABSTRACT FROM AUTHOR]

Focuses on clinical periodontology treatment of periodontitis-affected furcations of multirooted teeth. Impact of diagnosis of a furcational lesion; Morphology of the root complex of multirooted teeth; Proposal of therapeutic approaches.

Background: Different treatment modalities have been described for root coverage in cases of gingival recession. The aim of the present study was to evaluate the postsurgical outcome of 2 modes of surgical root coverage of predominantly shallow, Class I or II, gingival recessions. Methods: Fourteen buccal recession sites in 13 patients were treated with free connective tissue grafts employing a modified envelope technique; 14 sites in 9 patients were subjected to a coronally repositioned flap in combination with a bioabsorbable membrane. Immediately before surgery as well as after 6 months, gingival dimensions, i.e., width and thickness, as well as root coverage and attachment gain, were assessed to the next 0.1 mm employing a caliper, an ultrasonic device, and a pressure calibrated, computerized periodontal probe. Results: At the outset, mean recession depths amounted to 2.48+/-1.06 and 3.00+/-1.95 mm for patients treated with a free connective tissue graft and a bioabsorbable membrane, respectively. With the former technique, 80+/-24% root surface could be covered after 6 months, while the latter resulted in only 45+/-40% coverage. The contrast in reduction of recession width was even more pronounced (77+/-35% versus 18+/-37%). In both groups, an increase of gingival thickness of 0.6 to 0.7 mm was noticed. Conclusions: Small recessions may be covered more predictably with the modified envelope technique. 751. [ABSTRACT FROM AUTHOR]

Traumatic injury in the presence of a thin and narrow zone of gingival tissue may lead to gingival recession. Especially in class I and II recessions, root coverage may be accomplished with connective tissue grafts. in order to prevent recurrent recession. altering gingival dimensions width and thickness might he of advantage. In the present study. dimensions of gingiva were followed for 1 year after root coverage with connective tissue grafts. The study population consisted of 18 patients with a total of 28 class I or II recessions. Gingival width and depth of the recession were measured with a caliper, and thickness of the marginal tissue with an ultrasonic device. Periodontal probing depth was determined with a pressure-controlled electronic probe. Mean (± sd) recession depth at baseline was 3. 1 ± 1.4 mm. After 12 months, coverage amouted to 74± 30%. Width of gingiva rose from 2.1±1.0) mm to 3.2±1.4 mm, whereas thickness was increased from 0.8±0.3 mm to 1.5±0.7 mm. on average. No significant alteration of periodontal probing depth was observed but a mean gain of clinical attachment of 1.7±1.1 mm was ascertained. In a multiple regression analysis. recession depth and presence of the recession in the maxilla, but not tooth type significantly influenced relative root coverage (R²=0.34, p<0.01). Attachment gain tiller surgery depended on baseline attachment loss and was negatively influenced by smoking. The present results point to the possibility of doubling gingival thickness alter root coverage with connective tissue grafts. [ABSTRACT FROM AUTHOR]

In a previous study on 42 young adult, periodontally healthy subjects without any attrition, abrasion or crown restoration, gingival thickness (GTH) was determined at facial aspects of premolars, canines and incisors by a novel ultrasonic device. GTH strongly depended on periodontal probing depth, width of gingiva (WG), and tooth type. Whereas the ratio of crown width to its length (CW/CL) was not identified as an explanatory variable, a significant influence of the subject was ascertained. The aim of the present study was to extend these analyses in order to identify subjects with different morphological characteristics of gingiva, i.e., gingival phenotypes. When employing cluster analysis on standardized parameters mean GTH, WG and CW/CL of upper canines, lateral and central incisors, 3 clusters were identified. Cluster A comprised 2/3 of subjects, displaying "normal" GTH, WG and CW/CL. Cluster B (n = 9, 21%) had a significantly thicker and wider gingiva, and a more quadratic form of upper front teeth. A 3rd cluster (cluster C, n = 5, 12%) was identified showing "normal" GTH, high CW/CL, but a narrow zone of keratinized tissue. Some characteristics of gingival phenotype of the upper front tooth region were also found at upper premolars (WG, CW/CL) but in general not at mandibular teeth. Present results clearly indicate evidence for the existence of different gingival phenotypes. Clinical relevance of these observations has to be tested in longitudinal studies. [ABSTRACT FROM AUTHOR]

In the present study, recall data of 29 patients with advanced periodontitis were utilized to calculate diagnostic test parameters for bleeding scores or increased residual probing depth on increase of periodontal probing depth of &ges;2 mm after 2 years, comparing the simple binomial and correlated binomial model. 5.6% of sites were identified, where the periodontal probing depth increased 2 mm or more during 2 years of maintenance. Within-patient correlation coefficient of sites were found to be small in general (ρ < 0.02), with the exceptions for predictive value of a positive test for frequent (&ges;¾ times) bleeding on probing and residual probing depth of &ges;4 mm (ρ=0.137 and ρ=0.086, respectively), and specificity for no bleeding (ρ= 0.151). Point estimates of test parameters generally did not differ between simple binomial and correlated binomial model. The respective standard deviations were either over- or underestimated in the simple binomial model, it was concluded that the suggestion of a limited diagnostic value of bleeding scores or increased residual postoperative probing depth to predict recurrence of periodontitis cannot be rejected after application of a correlated binomial model. [ABSTRACT FROM AUTHOR]

Considerable problems have been reported in the eradication of Actinobacillus actinomycetemcomitans from periodontal sites. The present communication describes the 2-year results of a comprehensive combined mechanical/surgical and adjunctive minocycline (200 mg/day for 3 and another 2 weeks) treatment regiment in 28 patients with A. actinomycetemcomitans-associated periodontitis. Elimination of A. actinomycetemcomitans at periodontal sites was a prerequisite for gain of clinical attachment of &ges; mm or decrease of probing depth to &les; 4 mm after subgingival scaling plus minocycline (p&les;0.01). Whereas 2 years after active treatment A. actinomycetemcomitans could not be detected at monitored sites in 23 patients, the organism was found on buccal mucosa and in saliva in 17 and 12 cases, respectively. One or 2 years after periodontal surgery there was a significant association between log10-numbers of A. actinomycetemcomitans in buccal samples and numbers of residual pockets of &ges; 7 mm as well as gingival sites with overt gingivitis (R2=0.687, p<0.001). Present results indicate failure of an even prolonged administration of adjunctive minocycline to eliminate oral A. actinomycetemcomitans in most cases of A. actinomycetemcomitans associated periodontitis. [ABSTRACT FROM AUTHOR]

The morphological composition of the subgingival plaque associated with active periodontitis lesions and comparable inactive control lesions were determined in a 36-year-old patient with advanced periodontal disease. Monthly measurements of the clinical attachment level were subjected to linear regression analysis as a function of time. Attachment loss was recorded during the monitoring period at 10 sites, with loss of 2 mm or more at 6 sites. Plaque samples taken from these 6 sites and from 6 control sites with similar clinical conditions were not of uniform composition. Active lesions harboured on average 46% more cocci and twice as many large spirochetes as inactive control lesions. A linear regression analysis of the proportions of different morphotypes in the subgingival plaque versus the calculated monthly attachment loss rate at the time of sampling provided only very weak correlations, if at all. The observations made in the patient under investigation suggest that there is no great probability of suspected differences in the floras of active and inactive lesions being detected by dark-field analysis alone. The role of motile rods and spirochetes may have been overrated hitherto. [ABSTRACT FROM AUTHOR]

The aim of the present study was to relate shifts in the composition of subgingival plaque in periodontal pockets to alterations of the clinical periodontal conditions following a single course of subgingival scaling and root planing during a period of professional supragingival plaque control. For this purpose, 36 pairs of contralateral periodontal pockets in 10 subjects with moderately advanced periodontitis were assessed for the degree of gingival inflammation, probing pocket depths, bleeding on probing, attachment levels and the amount of supragingival plaque. In addition, samples of subgingival plaque were analyzed morphologically by dark-field microscopy. All patients received detailed information about proper oral hygiene and every 1-2 weeks, professional removal of supragingivally located deposits. When the oral hygiene standard had been sufficiently improved, 1 course of subgingival scaling on 1 side of each jaw only (test side) was carried out. Clinical and microbiological examinations were repeated after the scaling as well as after 2 and 6 months, while patients were recalled for supragingival prophylaxis every 2nd to 4th week. Our data showed that a single course of subgingival scaling and root planing resulted in reduced probing depths. a gain in clinical attachment and a shift in the composition of the subgingival microflora to a composition found in relatively healthy periodontal conditions. In relatively shallow pockets, however, a possible influence of repeated sampling on the subgingival microflora could not be ruled out. Bleeding on gentle probing was a reliable parameter for predicting a subgingival microflora where motile bacteria hold an increased portion. The differences in the subgingival microflora between sites exhibiting gain in clinical attachment after 6 months and non-responding sites, could not be confirmed statistically. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to study whether or not artificial crown margins at the gingival margin are compatible with periodontal health. periodontal conditions and the composition of subgingival plaque of 47 crowned teeth, 22 with crown margins at the gingival margin and 25 with a supragingival location of the margin, in 5 patients with extensive fixed bridgework has been examined 1 year after prosthetic treatment. Patients had been treated for periodontal disease and were recalled for prophylaxis sessions once every 2nd or 3rd month. Clinical data indicated little inflammation of the gingival tissues of crowned teeth with margins at the gingiva while at teeth with a supragingival location of the crown margin, gingival tissues showed minor or even no clinical signs of inflammation. In general, the composition of the subgingival plaque was similar to a flora regularly found to be associated with healthy conditions. [ABSTRACT FROM AUTHOR]

This paper argues for the "classicity" of Durkheim `s first book: the innovative way viewing the compatibility of social order and individual autonomy; his sensitive perception of uneasiness with regards to the crisis of anomie; the lucid sociological account, especially the tripartite explanation of the division of labor in terms of its functioning, emergence, and consequences; and the conceptualization of the problem of order--i.e., the relationship of differentiation and integration. In all of these respects, Durkheim's book is a classic. Yet "classical" neither means original nor flawless. This is shown with respect to the relationship of division of labor and organic solidarity by looking at the historical debate on the division of labor, by elucidating mechanical and organic solidarity, and by carving out some of the problems "inside organic solidarity." [ABSTRACT FROM AUTHOR]

We have cloned and sequenced the gene for a type-III Fc receptor from a Streptococcus dysgalactiae strain isolated from bovine mastitis and report here the complete sequence of the gene. The 1992-nucleotides-long open reading frame codes for a protein of 664 amino acids with a predicted molecular mass of 72 kDa (including the signal peptide). The C-terminal part of the protein is very similar to other streptococcal type-III receptors but contains five homologous IgG-binding domains compared to two or three in earlier reported Fc receptors of this type. Upstream of the IgG-binding domains, there is a unique sequence containing short repeated motifs. Subcloning different parts of the gene and expressing them as maltose-binding fusion proteins revealed that the upstream part is mediating binding to the plasma proteinase inhibitor α2-macroglobulin after its complex formation with proteases. In contrast to earlier described type-III Fc receptors, this molecule does not bind human serum albumin. [ABSTRACT FROM AUTHOR]

A gene encoding a fibronectin binding protein (FnBP) has recently been isolated and sequenced from Staphylococcus aureus strain 8325-4. In the same bacterial strain, 682 bp downstream to the stop codon of this gene (fnbA), a second gene termed fnbB has now been discovered, encoding another FnBP (FnBPB). The two genes show in large parts striking sequence homologies. The complete amino acid sequence encoded by fnbB has been deduced and compared to that deduced from fnbA. In FnBPB a stretch of 66 amino acids downstream to the signal peptide has 75% identity with the corresponding region in FnBPA. At the C-terminal site another 394 amino acid stretch is almost identical in both gene products. This stretch contains the 38 amino acid long D repeats, the wall spanning Wr repeats and the hydrophobic membrane spanning domain. In FnBPA each of the three D repeats has been identified as a fibronectin binding structure. These structures are highly conserved in FnBPB and most likely represent the major Fn-binding domain of this protein. However, a subclone of gene fnbB lacking the coding region for the D repeats also clearly expresses fibronectin binding activity. This additional binding site is so far unique for FnBPB and interacts like the D domains with the N-terminal 24–31-kDa fragment of fibronectin. The purified recombinant FnBP fragment (not containing the D repeats) completely inhibits the binding of fibronectin to whole cells of S. aureus. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor on the analysis of the present evidence for an association between periodontal disease and atherosclerosis. Most important confounding factor in the analysis of an association between periodontal disease; Relative risk of periodontitis.