bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporal trends in the prescription of vitamin K antagonists in patients with atrial fibrillation
Authors: FRIBERG J. , GISLASON G. H. , GADSBOELL N. , RASMUSSEN J. N. , RASMUSSEN S. , ABILDSTROM S. Z. , KØBER L. , MADSEN M. , TORP‐PEDERSEN C.
Published: December 2005

Objectives.  Anticoagulation therapy is recommended in patients with atrial fibrillation (AF) and risk factors for stroke. We studied the temporal trends in the prescription of vitamin K antagonists (VKA) in patients with a first hospital diagnosis of AF in Denmark, 1995–2002.

Design.  The Danish National Hospital Registry was used to identify subjects with a first hospital diagnosis of AF and the Danish Register of Medical Products Statistics to determine the proportion of these patients who claimed a prescription of VKA within 3 months from discharge.

Results.  Amongst 68 546 patients aged 50–99 years with a diagnosis of AF who survived 3 months following discharge, 24 991 (36%) patients claimed a prescription of VKA within 3 months. In both men and women a gradual increase in the use of VKA with time was observed, the relative increase being largest amongst the 80‐ to 99‐year olds. In all age groups, the prescription of VKA was lower in women than in men, including patients with a prior or concurrent stroke.

Conclusions.  From 1995 to 2002 the proportion of AF patients receiving VKA therapy increased significantly but the use of VKA therapy amongst women was lagging behind that of men. Even in patients with AF and prior stroke, the use of VKA seems to be less than optimal.
Three‐Dimensional Representation of the Neurotransmitter Systems of the Human Hypothalamus: Inputs of the Gonadotrophin Hormone‐Releasing Hormone Neuronal System
Authors: Dudas B. , Merchenthaler I.
Published: December 2005

The gonadotrophin‐releasing hormone (GnRH) represents the final common pathway of a neuronal network that integrates multiple external and internal factors to control fertility. Among the many inputs GnRH neurones receive, oestrogens play the most important role. In females, oestrogen, in addition to the negative feedback, also exhibits a positive feedback influence upon the activity and output of GnRH neurones to generate the preovulatory luteinising hormone surge and ovulation. Until recently, the belief has been that the GnRH neurones do not contain oestrogen receptors and that the action of oestrogen upon GnRH neurones is indirect, involving several, oestrogen‐sensitive neurotransmitter and neuromodulator systems thattrans‐synaptically regulate the activity of the GnRH neurones. Although this concept still holds for humans, recent studies indicate that oestrogen receptor‐beta is expressed in GnRH neurones of the rat. This review provides three dimensional stereoscopic images of GnRH‐immunoreactive (IR) and some peptidergic (neuropeptide Y‐, substance P‐, β‐endorphin‐, leu‐enkaphalin‐, corticotrophin hormone‐releasing‐ and galanin‐IR) and catecholaminergic neurones and the communication of these potential oestrogen‐sensitive neuronal systems with GnRH neurones in the human hypothalamus. Because the post‐mortem human tissue does not allow the electron microscopic identification of synapses on GnRH neurones, the data presented here are based on light microscopic immunocytochemical experiments using high magnification with oil immersion, semithin sections or confocal microscopy.
Mutator mutants of Escherichia coli carrying a defect in the DNA polymerase III τ subunit
Authors: Pham Phuong T. , Zhao Wei , Schaaper Roel M.
Published: December 2005

To investigate the possible role of accessory subunits of Escherichia coli DNA polymerase III holoenzyme (HE) in determining chromosomal replication fidelity, we have investigated the role of the dnaX gene. This gene encodes both the τ and γ subunits of HE, which play a central role in the organization and functioning of HE at the replication fork. We find that a classical, temperature‐sensitive dnaX allele, dnaX36, displays a pronounced mutator effect, characterized by an unusual specificity: preferential enhancement of transversions and −1 frameshifts. The latter occur predominantly at non‐run sequences. The dnaX36 defect does not affect the γ subunit, but produces a τ subunit carrying a missense substitution (E601K) in its C‐terminal domain (domain V) that is involved in interaction with the Pol III α subunit. A search for new mutators in the dnaX region of the chromosome yielded six additional dnaX mutators, all carrying a specific τ subunit defect. The new mutators displayed phenotypes similar to dnaX36: strong enhancement of transversions and frameshifts and only weak enhancement for transitions. The combined findings suggest that the τ subunit of HE plays an important role in determining the fidelity of the chromosomal replication, specifically in the avoidance of transversions and frameshift mutations.
A calcium‐dependent protein kinase regulates Plasmodium ookinete access to the midgut epithelial cell
Authors: Ishino Tomoko , Orito Yuki , Chinzei Yasuo , Yuda Masao
Published: December 2005

Plasmodium parasites are fertilized in the mosquito midgut and develop into motile zygotes, called ookinetes, which invade the midgut epithelium. Here we show that a calcium‐dependent protein kinase, CDPK3, of the rodent malarial parasite (Plasmodium berghei) is produced in the ookinete stage and has a critical role in parasite transmission to the mosquito vector. Targeted disruption of the CDPK3 gene decreased ookinete ability to infect the mosquito midgut by nearly two orders of magnitude. Electron microscopic analyses demonstrated that the disruptant ookinetes could not access midgut epithelial cells by traversing the layer covering the cell surface. An in vitro migration assay showed that these ookinetes lack the ability to migrate through an artificial gel, suggesting that this defect caused their failure to access the epithelium. In vitro migration assays also suggested that this motility is induced in the wild type by mobilization of intracellular stored calcium. These results indicate that a signalling pathway involving calcium and CDPK3 regulates ookinete penetration of the layer covering the midgut epithelium. Because humans do not possess CDPK family proteins, CDPK3 is a good target for blocking malarial transmission to the mosquito vector.
Studies on the fish catch efficiency of different types of fishing gear in Kaptai Reservoir, Bangladesh
Authors: Ahmed Khan Kamal U. , Hambrey John B.
Published: December 2005

A comprehensive analysis of the efficiency of different fishing gear in capturing Cyprinidae (major carp) species in Kaptai Reservoir, Bangladesh, was conducted. The catch per unit effort (CPUE) data were collected during a 1‐year survey, covering a total of 493 independent fishing units spread across the four major fishing grounds of the reservoir. The study examines the CPUE and catch composition between months and study sites, and the effects of reservoir water level fluctuations, gear diversity and fish distribution patterns on the fish catches. The mean CPUE for all gear ranged between 2.91 and 30.86 kg unit−1 day−1. Analysis of variance showed significant differences among the fishing gear types. The CPUE differed significantly between months for lift nets, large‐meshed (LM) gill nets, cluster hooks and hand lines. None of the fishing gear exhibited significant differences between sites except for cluster hooks. The CPUE of small‐meshed (SM) seine nets was significantly higher than that of other gear. The reasons for such differences in the fish catches were identified as the choice of fishing places, the net sizes, the number of hooks, lures and baits, water turbidity, wind, waves and rainfall. The CPUE indices for lift nets showed significant variation between months for the Cyprinidae species. A significant variation in catch at the different sites was found for all nets, except SM seine nets. The contribution of the Cyprinidae species showed significant differences between sites only for hand lines. The coefficient of variation of CPUE for fishing nets did not vary much more than 55% (lift net), whereas the highest variation of 49% was recorded for hand lines among the hooks and line. Higher reservoir water levels were followed by reduced CPUEs for the Cyprinidae species and vice versa, whereas the highest water levels corresponded to the higher CPUE for the Clupeidae species.
THE IMAGINATIVE DIMENSION OF AN EARLY EIGHTEENTH‐CENTURY GARDEN: WENTWORTH CASTLE
Authors: CHARLESWORTH MICHAEL
Published: December 2005

Responding to the implicit challenge in Stephen Bann's work to emphasize the poetics of gardens, the essay considers Wentworth Castle, Yorkshire, designed by the Earl of Strafford to be his monument. The essay finds a poetics of space at work in the domain, which guided visitors through a series of spectacular unfolding views across the Yorkshire landscape. Here Strafford commemorated the reign of Queen Anne, his own political eminence under her, and his subsequent secret political activities. In helping at a very early stage in its development to create the Gothic Revival, Strafford celebrates his own family and the renewal of Anglo‐Saxon studies in eighteenth‐century Britain.
GIVING UP ON HISTORY? CHALLENGES TO THE HIERARCHY OF THE GENRES IN EARLY NINETEENTH‐CENTURY FRANCE
Authors: DURO PAUL
Published: December 2005

This essay argues for the continuing importance of the hierarchy of the genres to French painting after the Revolution and for the hierarchy's destabilization through the introduction of new genres, notably the sub‐category of history painting known as ‘le genre historique’, in the early years of the nineteenth century. While history painting, traditionally the genre of choice of the ambitious artist and mainstay of academic ideology, remained pre‐eminent, historical genre painting's radical intervention unsettled traditional assumptions of artistic value and questioned the Academy's self‐proclaimed prerogative to legislate on artistic matters. It examines the development of historical genre painting in the light of these changes, particularly the shift in historical consciousness from the eighteenth‐century's Aristotelianism to the positivism of the nineteenth century. The essay concludes with a brief consideration of the relationship between historical genre painting, genre painting and the scenes of contemporary life called for in Baudelaire's celebrated essay, `The Painter of Modern Life'.
SOMETHING IS HAPPENING
Authors: SHIFF RICHARD
Published: December 2005

In The True Vine (1989), Stephen Bann assumes the role of Nietzschean ‘antiquarian’, a historian attentive to the slightest residues of material culture, the kind of historical evidence overlooked, or disregarded, by those more concerned either to monumentalize the existing historical record or fundamentally to shift its understanding. Bann's approach to history accommodates a certain modernist sense of the inexhaustible excess of meaning to be found within any material practice, an attitude towards media of representation here associated with the art criticism of Clement Greenberg but, all the more so, with the pragmatic philosophy of C.S. Peirce. Adopting Bann's ‘antiquarian’ spirit, this essay probes the cultural significance of the material factor in painting, photography, film, video and forms of digitized electronic display.
Space and exclusion: does urban morphology play a part in social deprivation?
Authors: Vaughan Laura , Clark David L Chatford , Sahbaz Ozlem , Haklay Mordechai (Muki)
Published: December 2005

There is currently a growing interest in the spatial causes of poverty, particularly its persistence. This paper presents methodological innovations that have been developed for investigating the relationship between physical segregation and economic marginalization in the urban environment. Using GIS to layer historical poverty data, contemporary deprivation indexes and space syntax measures of spatial segregation, a multivariate system has been created to enable the understanding of the spatial process involved in the creation and stagnation of poverty areas as well as to analyse the street segment scale of configuration.
Negotiating nature: exploring discourse through small group research
Authors: McGregor Andrew
Published: December 2005

The full potential of discussion groups to further geographic interest in the relationship between discourse, individual and society can still be developed further. This paper briefly reviews previous applications of discussion group methodologies before suggesting a new discourse‐centred approach that explores how broad social discourses impact everyday conversations. The approach is demonstrated through a case study involving supporters of environmental movements in Australia. It is concluded that small groups can be used in new ways that provide important methodologically unique insights into the reception of transient, but powerful, discourses upon everyday lives.
Erratic judgements: re‐evaluating solutional erosion rates of limestones using erratic‐pedestal sites, including Norber, Yorkshire
Authors: Goldie H S
Published: December 2005

The re‐interpretation of surface karst landforms in Northern England has led to a re‐examination of well‐known erratic‐pedestal sites that were the origin for karst denudation rates applied extensively, on the supposition that erratics protect underlying limestone from rainwater solution. Height of the pedestal has been used to calculate long‐term solutional‐lowering, as much as 50 cm in 15 ka (33.3 mm/ka) from UK sites. The sites include Norber and Scar Close, Yorkshire, UK. This paper shows that the sites have been misinterpreted, in particular at Norber where the erratics lie on a pre‐existing structurally stepped surface. Norber and several other sites also experience much mechanical weathering, in relatively weak, well‐fractured limestones, a process which must be distinguished from solution. Sites in strong, less‐fractured limestones demonstrate lower rates, which are sounder indications of land surface lowering. Some pedestals have been confirmed as partly resulting from solutional weathering in surrounding soil and vegetation. Re‐evaluation reduces solution rates to 3–13 cm in 15 ka. Applying such rates has profound implications for understanding limestone landscapes, challenging orthodox views.
Wetland sustainability and the evolution of indigenous knowledge in Ethiopia
Authors: DIXON ALAN B
Published: December 2005

Much research in recent years has addressed the contribution of indigenous knowledge (IK) to development initiatives in developing countries. An IK system that continuously evolves and adapts in response to environmental and socio‐economic change is often considered to be at the core of sustainable natural resource management practices and rural livelihoods. In the context of indigenous wetland management in western Ethiopia, this paper examines the relationship between IK and wetland sustainability, focusing on the mechanisms through which IK evolves and how local adaptive capacity is built up. A series of participatory research activities undertaken in four wetland communities revealed spatial variations in the degree of innovation and communication taking place. The paper argues that these mechanisms are key factors influencing adaptive capacity, suggesting a key link between wetland sustainability and the occurrence of innovation and communication among communities.
New views on an old forest: assessing the longevity, resilience and future of the Amazon rainforest
Authors: Maslin Mark , Malhi Yadvinder , Phillips Oliver , Cowling Sharon
Published: December 2005

The aim of this paper is to investigate the longevity and diversity of the Amazonian rainforest and to assess its likely future. Palaeoclimate and palaeoecological records suggest that the Amazon rainforest originated in the late Cretaceous and has been a permanent feature of South America for at least the last 55 million years. The Amazon rainforest has survived the high temperatures of the Early Eocene climate optimum, the gradual Cenozoic cooling, and the drier and lower carbon dioxide levels of the Quaternary glacial periods. Two new theories for the great diversity of the Amazon rainforest are discussed – the canopy density hypothesis and the precessional‐forced seasonality hypothesis. We suggest the Amazon rainforest should not be viewed as a geologically ephemeral feature of South America, but rather as a constant feature of the global Cenozoic biosphere. The forest is now, however, entering a set of climatic conditions with no past analogue. The predicted future hotter and more arid tropical climates may have a disastrous effect on the Amazon rainforest.
Accounting for Both Random Errors and Systematic Errors in Uncertainty Propagation Analysis of Computer Models Involving Experimental Measurements with Monte Carlo Methods
Authors: Vasquez Victor R. , Whiting Wallace B.
Published: December 2005

A Monte Carlo method is presented to study the effect of systematic and random errors on computer models mainly dealing with experimental data. It is a common assumption in this type of models (linear and nonlinear regression, and nonregression computer models) involving experimental measurements that the error sources are mainly random and independent with no constant background errors (systematic errors). However, from comparisons of different experimental data sources evidence is often found of significant bias or calibration errors. The uncertainty analysis approach presented in this work is based on the analysis of cumulative probability distributions for output variables of the models involved taking into account the effect of both types of errors. The probability distributions are obtained by performing Monte Carlo simulation coupled with appropriate definitions for the random and systematic errors. The main objectives are to detect the error source with stochastic dominance on the uncertainty propagation and the combined effect on output variables of the models. The results from the case studies analyzed show that the approach is able to distinguish which error type has a more significant effect on the performance of the model. Also, it was found that systematic or calibration errors, if present, cannot be neglected in uncertainty analysis of models dependent on experimental measurements such as chemical and physical properties. The approach can be used to facilitate decision making in fields related to safety factors selection, modeling, experimental data measurement, and experimental design.
Juvenile and rapidly progressive periodontitis
Authors: Çelenligil Haviye , Kansu Emin , Eratalay Kenan
Published: December 2005

Abstract Juvenile and rapidly progressive periodontitis are grouped under the heading of early‐onset periodontitis. In recent years, much attention has been devoted to studying immunologic factors in early‐onset periodontitis. This study was designed to investigate peripheral blood lymphocyte subpopulations, natural killer cells and interleukin‐2 receptor positive (IL‐2R +) cells in patients with juvenile and rapidly progressive periodontitis. 38 patients with juvenile and 30 patients with rapidly progressive periodontitis, plus 30 normal healthy control subjects were included in the study. Peripheral blood T‐lymphocytes, helper T‐cells, suppressor T‐cells, HLA‐DR+ cells, and IL‐2R+ cells were determined using appropriate monoclonal antibodies and the indirect immunofluorescence method. B‐lymphocytes were identified using the direct immunofluorescence technique. Both groups of patients had normal numbers of total CD3 + T‐cells, CD4+ helper T‐cells, CD8+ suppressor T‐cells, HLA‐DR+ cells and IL‐2R + cells. Natural killer cells were found to be significantly elevated in both groups. These findings could contribute to the immunopathogenesis of early‐onset periodontitis.
Periodontal alterations in patients with pemphigus vulgaris taking steroids
Authors: Markitziu Alice , Zafiropoulos Gregory , de Jacoby Lavinia Flores , Pisanty Sarah
Published: December 2005

Abstract Periodontal health parameters and salivary cortisol were studied in 19 adult pemphigus vulgaris patients on chronic steroid therapy. The patient population was divided into non‐medicated and medicated subjects at intake into the study. A significant difference between the 2 examinations, performed at an interval of 8.73 months ± 4.35, was found in bleeding index (p<0.000 and p<0.04, respectively) and gingival recession (p< 0.000 and p< 0.009) in both groups. No changes occurred in alveolar bone height. Steroid therapy altered the bleeding index (R = 0.60 and R = 0.80) and gingival recession (R = 0.87 and 0.91) in a dose‐related manner, and induced low salivary cortisol. The findings of this study would suggest suppression of the host inflammatory reaction, resulting in an alleged healthy clinical appearance of the periodontium.
Connective tissue repair in circumferential periodontal defects in dogs following use of a biodegradable membrane
Authors: Magnusson I. , Stenberg W. V. , Batich C. , Egelberg J.
Published: December 2005

Abstract A biodegradable polylactic acid membrane was evaluated for its ability to enhance periodontal regeneration. In 8 Labrador dogs, circumferential defects were created around the maxillary 1st premolars. The defects were combination “1‐wall vertical and horizontal”. A membrane was adjusted to cover the defect on one side of the jaw, while the contralateral tooth served as control without membrane. After 3 months, healing was evaluated histologically. The results demonstrated that the amount of connective tissue repair with newly formed cementum approximated 50% of the defect height for both test and control groups. Thus, no advantage to the use of membrane was found, which is contradictory to the findings of our previous dog study using the same biodegradable membrane. The possible reasons for this difference in results are discussed relative to suggested mechanisms for membrane effects in periodontal regeneration.
Periodontitis in the primary dentition associated with Actinobacillus actinomycetemcomitans infection and leukocyte dysfunction
Authors: Crossner Claes‐Göran , Carlsson Jan , Sjödin Bengt , Tärnvik Arne , Unell Lennart , Venge Per , Wranne Lars
Published: December 2005

Abstract 2 siblings, aged 5 years (girl) and 7 years (boy), with periodontitis in the primary dentition were studied. Actinobacillus actinomycetemcomitans was isolated from the gingival pockets of both children. The liters of IgG antibodies against A. actinomycetemcomitans were elevated, and the polymorphonuclear leukocytes had a decreased capacity to ingest IgG‐coated latex particles. Other functions of the polymorphonuclear leukocytes were normal. After antibiotic therapy and for the 7‐year‐old boy, debridement of the gingival pockets A. actinomycetemcomitans was no longer detectable in the gingival pockets, and the phagocytic capacity of the polymorphonuclear leykocytes was normalized. After 21/2 years, A. actinomycetemcomitans was found again in the gingival pockets of the boy, and once more his polymorphonuclear leukocytes had a decreased capacity to ingest IgG‐coated latex particles. The antibiotic therapy was repeated and 6 months later, the number of A. actinomycetemcomitans was very low and the phagocytic capacity of the polymorphonuclear leukocytes was back to normal. This case report suggests that A. actinomycetemcomitans may be involved in the etiology of periodontitis in the primary dentition, possibly by triggering a phagocytic dysfunction of polymorphonuclear leukocytes.
Effect of non‐eugenol‐ and eugenol‐containing periodontal dressings on the incidence and severity of pain after periodontal soft tissue surgery
Authors: Jorkjend L. , Skoglund L. A.
Published: December 2005

Abstract This study examines the incidence and severity of postoperative pain after gingivectomy using one non‐eugenol‐containing periodontal dressing, Coepak (n=76) and 2 eugenol‐containing periodontal dressings. Wondrpak (n=64) and Nobetec (n=86). All patients were subjected to gingivectomy using 1 type of local anaesthesia (lidocaine + adrenalin) only and covering the surgical areas with either of the 3 different dressings in a randomized study. Postoperative pain was assessed on 100 mm visual analogue scales over 5 days starting immediately after surgery. No pain was reported by 22.0% of the patients after Coe‐pak, 23.4% after Wondrpak and 30.2% after Nobetec, 13.2% of the patients took analgesics after Coe‐pak treatment, 3.1% after Wondrpak and 1.2% after Nobetec. Mean pain score after Coe‐pak was higher (P<0.05) than after Nobetec 2 h after operation until the morning on the 3rd postoperative day. Mean pain score after Coe‐pak was higher (P<0.05) than after Wondrpak 3 h to 9 h after operation. No statistically significant difference was found between Wondrpak and Nobetec regarding mean pain score.
The significance of alveolar bone in periodontal disease
Authors: Brägger U. , Nyman S. , Lang N. P. , von Wyttenbach Th. , Salvi G. , Schürch E.
Published: December 2005

Abstract The periodontal conditions in 19 patients with unilateral cleft lip, alveolus and palate (CLAP) and in 6 patients with bilateral CLAP, were evaluated in 1979 and re‐examined in 1987. During these 8 years, these patients were not subjected to any professionally supervised maintenance care program. Pronounced plaque accumulation and high frequency of gingival units exhibiting bleeding on probing were noted in the majority of the patients both in 1979 and 1987, documenting inadequate oral hygiene standards with resulting inflammatory reactions of the periodontal tissues. Progression of periodontal disease over time was assessed as loss of clinical attachment and loss of alveolar bone height. The periodontal destruction was not found to be more severe at cleft sites with a long connective tissue attachment than at control sites not affected by cleft defects. It was concluded that sites with a long supracrestal connective tissue attachment do not seem to be more prone to periodontal destruction, induced by bacterial infection, than sites with a normal length of the supraalveolar fibrous attachment. The results also show that the alveolar bone height, as visualized in radiographs at sites with alveolar defects, is of limited value for the diagnosis of the degree of periodontal destruction at such sites.
Fate of pocket epithelium in an apically positioned flap
Authors: Pippin David J.
Published: December 2005

Abstract The fate of periodontal pocket epithelium when sulcular incisions are used in apically positioned flap surgery was investigated by serial histology. Human subjects received apically positioned flap segments on the facial aspect of anterior teeth timed to give 1, 3, 5, 7, 21 and 35 days of healing on the day of extraction. Companion surgeries for comparison consisted of similar flaps, but utilized an inverse bevel primary incision. Assessment of the sulcular incision specimens revealed that epithelial degeneration and dissolution occurred within 7 days and resulted in a collagen‐to‐collagen attachment of the periodontal flap to the alveolar bone. The inverse bevel incision was consistently effective in removing the pocket epithelium and resulted in healing by a connective tissue union of the flap to the alveolar bone. By 21 days of healing, the 2 surgical methods were indistinguishable histologically. On the basis of this investigation, it is suggested that the inverse bevel primary incision traditionally advocated for apically positioned flap surgeries may be replaced by the more rapid and simple sulcular incision as the preferred technique.
Rapid periodontal destruction in adult humans with poorly controlled diabetes A report of 2 cases
Authors: Ainamo J. , Lahtinen A. , Uitto V.‐J.
Published: December 2005

Abstract Out of a pool of 12 middle‐aged or elderly diabetic patients demonstrating rapid periodontal break‐down, the 2 oldest cases with follow‐up periods of 19 and 16 years are described. The common feature of all 12 patients was that they were either unaware of or unable to control their diabetic condition at the time of the active, stage of their periodontal disease. The bone loss progressed in spite of specialist periodontal care and the patients again responded to treatment only after their elevated blood glucose levels had been brought back to normal. Thus, the rapid periodontal breakdown was not found to be associated with the diabetic condition per se, but rather with the hyperglycemia. This clinical follow‐up study does not answer the question of whether rapid periodontal destruction occurs in all patients with poorly controlled diabetes. Neither do the observations imply that rapid bone loss would be pathognomic of high blood glucose levels. However, the observations seem to suggest that there may be an inter‐relationship between rapid periodontal breakdown and elevated blood glucose levels. Therefore, any sudden change towards an increased progression rate of periodontal breakdown at adult age, as observed from periodic radigraphs with intervals of only a few years, should be followed up with a medical examination in order to outrule or verify the possibility of a high blood glucose level.
A clinical and microbiological comparison of the effects of water and 0.02% chlorhexidine as coolants during ultrasonic scaling and root planing
Authors: Taggart J. A. , Palmer R. M. , Wilson R. F.
Published: December 2005

Abstract The maxillary teeth of 10 patients with moderately advanced chronic periodontitis were treated in a split‐mouth design study. The baseline examination included plaque and bleeding scores, probing depths and probing attachment levels. 2 sites in each quadrant were selected for dark‐field microscopic analysis. Each quadrant was randomly assigned to test or control and instrumented with an ultrasonic sealer using either 0.02% chlorhexidine or water as the coolant. Measurements were repeated 2, 6 and 10 weeks later, together with additional plaque sampling. Ultrasonic instrumentation with either chlorhexidine or water was equally effective in reducing bleeding scores and improving probing attachment levels. 42% of chlorhexidine‐ and 38.7% of water‐treated sites showed gains of 1 mm or more in clinical attachment. Mean reductions in probing depth were similar (0.9 mm chlorhexidine, and 0.8 mm water). At the final examination, the chlorhexidine‐treated quadrants had significantly more sites with probing depths in the 1–3 mm category and less in the >3 mm category than the control quadrants (P<0.05). Both treatments reduced the microscopic counts of motiles and spirochaetes, resulting in a subgingival microbiota consistent with periodontal health. The results indicate that chlorhexidine has a slight adjunctive effect in the reduction of pocket depth when used as a coolant during ultrasonic root planing for the treatment of chronic periodontitis.
The role of histopathology in the diagnosis and prognosis of periodontal diseases
Authors: Gillett I. R. , Johnson N. W. , Curtis M. A. , Griffiths G. S. , Sterne J. A. C. , Carman R. J. , Bampton J. L. M. , Wilton J. M. A.
Published: December 2005

Abstract The histological evaluation of surgical biopsies from affected tissues is a standard way of assessing pathological change and determining treatment in many diseases. In most forms of periodontal disease, however, this approach finds limited application. Here, we review what uses the histopathological approach has in the study and evaluation of the periodontal diseases. Current understanding of the changes in epithelial anatomy during pocket formation, the cellular composition and dynamics of the inflammatory infiltrate and the mechanisms of bone resorption and repair are reviewed from the perspective of the information available from microscopical investigation, including the uses and potential application of modern immunocytochemical methods to these questions. The usefulness of histological study of biopsy material is reassessed in the light of advances made in immunohistochemical techniques and their application to gingival inflammatory infiltrates and epithelia. Such techniques offer immediately valuable research opportunities with potential for diagnostic applications, noteably the recognition of phases of destructive activity and their differentiation from periods of effective host defence.
5‐year results of a longitudinal study of early periodontitis in 14‐ to 19‐year‐old adolescents
Authors: Clerehugh Valerie , Lennon Michael A. , Worthington Helen V.
Published: December 2005

Abstract This 5‐year longitudinal study monitored 167 subjects at ages 14.3, 16.0 and 19.6 years. The aims were (1) to determine loss of attachment ≥ 1 mm in the study group over the 5‐year period; (2) to relate baseline levels of oral deposits and gingivitis to the 5‐year increment of loss of attachment; (3) to determine whether subjects who had developed loss of attachment ≥ 1 mm by age 16 years were more susceptible to further development of loss of attachment; (4) to evaluate loss of attachment indices. Loss of attachment, plaque, subgingival calculus, gingival bleeding and gingival colour change were measured. At baseline, 3% of subjects had loss of attachment ≥ 1 mm and < 1% of sites were involved. By age 19 years, 77% had loss of attachment ≥ 1 mm, and 31% of sites were affected. There was a significant correlation between the presence of subgingival calculus at baseline and the 5‐year increment of loss of attachment (Pearson's r= 0.26 p < 0.001). Subjects who had developed loss of attachment by age 16 years still had significantly more sites affected at the more severe 2 mm level 3 years later than their peers (p < 0.05). The results suggest that a flexible approach is needed in selecting indices of loss of attachment for epidemiological investigations.
Absence of bleeding on probing An indicator of periodontal stability
Authors: Lang Niklaus P. , Adler Rolf , Joss Andreas , Nyman Sture
Published: December 2005

Abstract Following active periodontal therapy, 41 patients were incorporated in a maintenance program for 2 1/2 years with recall intervals varying between 2–6 months. At the beginning of each maintenance visit, the periodontal tissues were evaluated using “bleeding on probing” (BOP). Reinstrumentation was only performed at sites which bled on probing. However, supragingival plaque and calculus was always removed. Pocket probing depths and probing attachment levels were recorded after active treatment and at the conclusion of the study. Progression of periodontal disease was defined by an observed loss of probing attachment of ≥ 2 mm. The reliability of the BOP test as a predictor was evaluated by calculating sensitivity, specificity, accuracy, and positive and negative predictive values. While only a 29% sensitivity was calculated for frequent bleeding, the specificity was 88%. The fact that the positive predictive value for disease progression was only 6% and the negative predictive value was 98% renders continuous absence of BOP a reliable predictor for the maintenance of periodontal health.
The prevalence of overhanging dental restorations and their relationship to periodontal disease
Authors: Brunsvold Michael A. , Lane James J.
Published: December 2005

Abstract Overhanging dental restorations (ODR) are a major dental health problem. An ODR is defined as an extension of restorative material beyond the confines of a cavity, preparation. They have been strongly implicated as an etiologic factor in the progression of periodontal disease and are alarmingly prevalent. In addition to promoting plaque accumulation, they change a nondestructive subgingival flora to a destructive one. There is good documentation that bleeding, gingivitis, and bone loss increase in tissues adjacent to ODR as compared to homologous teeth. Removal of ODR enhances the effectiveness of the hygienic phase of periodontal therapy. Many ODR, however, are not detected on radiographs and are evident only by use of an explorer directed subgingivally. For this reason and others, many are not removed. This literature review summarizes research concerning the prevalence, significance and removal of ODR.
Diagnostic predictability of scores of plaque, bleeding, suppuration and probing depth for probing attachment loss
Authors: Claffey Noel , Nylund Karin , Kiger Robert , Garrett Steve , Egelberg Jan
Published: December 2005

Abstract Recordings of supragingival plaque, bleeding, suppuration and probing depth were obtained for 42 months following initial periodontal therapy. Scores accumulated after various time intervals during monitoring were studied for their predictive value in revealing probing attachment loss as determined by regression analysis during the 0–42 month period. Accumulated plaque scores demonstrated low predictability. Accumulated bleeding scores showed modest predictive values. Suppuration on probing was not a frequent finding during the observation interval and also had modest predictive power. Increase in probing depth compared to baseline and deep residual probing depth had modest predictability after 3 and 12 months, but showed increasing accuracy in revealing probing attachment loss over later time intervals. After a few years of maintenance, increase in probing depth, particularly if combined with high frequency of bleeding on probing, showed the highest predictive value for probing attachment loss of the scores examined.
Comparison of plaque microflora between Chinese and Caucasian population groups
Authors: Cao C. F. , Aeppli D. M. , Liljemark W. F. , Bloomquist C. G. , Bandt C. L. , Wolff L. F.
Published: December 2005

Abstract This investigation was designed to compare the predominant plaque micro‐organisms from a Chinese group of patients exhibiting periodontitis with an age‐, sex‐ and periodontal disease‐matched Caucasian group of patients. In addition to race, the 2 population groups differed with respect to diet and oral hygiene habits, or effectiveness at removing plaque. Clinical measurements were determined along with an evaluation for micro‐organisms in supragingival and subgingival plaque. Although the Chinese and Caucasian population groups were similar with respect to composition of micro‐organisms in subgingival plaque, notable differences were observed in supragingival plaque. The Chinese group had higher mean proportions of spirochetes. motile rods, Fusobocterium spp. and dark‐pigmented Bacteroides species, while the Caucasian group had higher mean proportions of cocci, total Actinomyces spp., A. viscosus and total Streptococcus spp. in supragingival plaque. The microbial differences observed in supragingival plaque may be explained at least in part, if not totally, by the higher plaque index scores of the Chinese versus Caucasian population groups.
Concepts determining statistical analysis of dental data
Authors: McDonald Barry W. , Pack Angela R. C.
Published: December 2005

Abstract This paper reviews some approaches to statistical analysis of dental data. Often dental data consist of more than one observation per patient which may not be independent, and consequently some standard statistical methods based on independence of all observations are inappropriate. This paper seeks to make the dental researcher and the consulting statistician aware of some of the efficient approaches that can be used to analyse the data successfully. No specialist statistical knowledge is assumed. Rather the goal is to increase awareness of what can be done. The statistical layman is introduced to some basic concepts, while references are given for the mathematically‐minded reader. The data of Pack, Coxhead and McDonald is used as a springboard for this discussion.
Human histologic responses to guided tissue regenerative techniques in intrabony lesions
Authors: Stahl S. S. , Froum S. , Tarnow D.
Published: December 2005

Abstract 9 sites of 8 teeth in 5 adults with severe periodontitis were treated by open surgical debridement followed by placement of 1 of 2 Teflon barrier membranes. Teeth were notched at both gingival margins and deepest visible calculus on the root. Barrier membranes were placed apical to alveolar crest and coronal to gingival notch. Flaps were sutured coronally and patients were placed on 1.2% chlorohexodine gluconate twice daily for 2 weeks, post‐surgery. Subsequent to suture removal, patients returned for frequent plaque control until block removal. In order to observe early healing responses, 6 sites were harvested 5 to 8 weeks after surgical treatment. 3 additional sites were removed 14, 22 and 30 weeks respectively after surgical treatment. Histologically, new cementum was seen in a linear direction along root surfaces in 6 out of 9 sites (length of cementum = 0.5 to 1.7 mm). 3 sites showed no evidence of new attachment. At sites of cementogenesis, functionally‐oriented fibers were inserted. The osseous seams opposite the new attachment often demonstrated osteogenesis. Regenerative responses were seen with both types of teflon membranes and were present as early as 5 weeks after surgery.
Serum antibodies and loss of periodontal bone in patients with rheumatoid arthritis
Authors: Tolo Kåre , Jorkjend Lars
Published: December 2005

Abstract The number of teeth, % of alveolar bone loss, serum IgG, and serum antibodies to Bacteroides gingivalis, Capnocytophaga ochracea and Eubacterium saburreum were recorded in 37 patients diagnosed with rheumatoid arthritis (RA) and in an age‐and sex‐matched control group of 37 individuals free from RA. The RA group had a significantly increased loss of teeth and loss of alveolar bone compared to the control group. The RA patients also had a significantly increased level of serum IgG. In the total material, 26% of the variation in loss of alveolar bone was accounted for by age, diagnosis of rheumatoid arthritis, and levels of antibodies against B. gingivalis and E. saburreum. In the RA group, 48% of this variation was accounted for by age, total serum IgG and IgG antibodies to B. gingivalis and E. saburreum.
Effect of cigarette smoking on periodontal healing following surgical therapy
Authors: Preber Hans , Bergström Jan
Published: December 2005

Abstract The influence of cigarette smoking on the outcome of surgical therapy was investigated in 54 patients, 24 of whom were smokers. The patients had moderate to severe periodontitis with persisting diseased pockets after non‐surgical therapy. The surgical modality used was the modified Widman flap operation and the pockets under scrutiny were those with an initial probing depth of 4–6 mm. Re‐examination was made 12 months following the completion of surgery. The probing depth reduction at the 12‐month follow‐up was 0.76±0.36 mm (mean±SD) in smokers as compared to 1.27 0.43 mm in non‐smokers. The difference was statistically significant (P<0.001) and persisted after accounting for plaque. The results suggest that smoking may impair the outcome of surgical therapy.
Subjective criteria and probing attachment loss to evaluate the effects of plaque control and root debridement
Authors: Vanooteghem Rik , Hutchens L. H. , Bowers Gerald , Kramer Gerald , Schallhorn Robert , Kiger Robert , Crigger Max , Egelberg Jan
Published: December 2005

Abstract 11 adult patients with moderate to advanced periodontitis were treated with oral hygiene instruction and an initial, single episode of root debridement. Before therapy, 3 independent clinicians examined all patients and identified sites that in their opinion probably would not respond to the therapy and would continue to lose attachment. On 2 occasions, 3 and 12 months later, the clinicians reexamined and reevaluated all patients and all sites. The results of therapy were also monitored by probing attachment level measurements performed every 3rd month. All 11 patients completed 24 months of follow‐up, and 6 subjects were available until 36 months. Sites with probing attachment loss after 12, 24 and 36 months were identified using linear regression analysis and compared to the clinicians' prediction of probing attachment loss. The results demonstrated a limited agreement between probing attachment loss determined by linear regression and the clinicians' predictions of probing attachment loss. It appears that the traditional clinical signs and factors used to forecast and identify periodontal disease activity are only moderately associated with probing attachment loss. This suggests that attachment loss may be caused by several factors, at least following initial therapy. The progression of an inflammatory disease of microbial etiology may be only 1 of such causes. Further studies are needed to clarify the nature and cause of probing attachment loss.
Controlled force measurements of gingival attachment level made with the Toronto automated probe using electronic guidance
Authors: Karim Minaz , Birek Peter , McCulloch Christopher A.
Published: December 2005

Abstract Precise reproduction of probe placement, probing force and probing angulation may influence the reliability of replicate gingival attachment level measurements (GAL). Reproducibility of GAL measurements was determined with the Toronto automated periodontal probe (TAPP) in which a novel electronic guidance system was incorporated to improve the precision of probing angulation. Bench testing of forces produced at the probe tip was performed with an electronic balance. Reproducibility and precision of force generation were tested in a variety of instrument configurations using laboratory models. The data indicated that highly precise and reproducible probing forces can be generated with the TAPP over a large (10 to 90 g) probing range. Instrument precision was ±0.27 mm when probing forces of 40–60 g were used. The guidance system provided accurate and reproducible measurements of the probe handle in both roll and pitch axes when compared with precisely machined wedges (R = 0.99, roll; R=0.98, pitch). Deviation of probing angulation greater than 5° on replicate measurements of GAL was associated with significant alterations in the location of circumferential probe placement and in the size of the difference between GAL measurements (ΔGAL). Clinical assessment of probing angulation in 6 patients demonstrated that ΔGAL was 0.40 ± 0.05 mm when probing angulation deviation was less than 5° but increased to 0.96 ± 0.11 mm when deviations exceeded 5°. Taken together, these data indicate that the regulation of probing angulation in clinical measurement of GAL with the TAPP is an important determinant of the reproducibility of periodontal probing.
Clearance of a topically applied fluorescein gel from periodontal pockets
Authors: Oosterwaal P. J. M. , Mikx F. H. M. , Renggli H. H.
Published: December 2005

Abstract The clearance of a fluorescein gel applied with an irrigation technique in periodontal pockets was studied. In order to evaluate the time a drug remains in a periodontal pocket, the alteration in concentration of this drug in a given time period was investigated. After application of the gel in 4 pockets of 10 patients, samples were taken from 1 of the 4 pockets at 5, 10, 20 and 40 min. The results show that in the 1st phase, directly after application, most of the gel disappeared from the pocket, while in the 2nd phase, the fluorescein gel is washed out with a calculated 50% reduction time of 12.5 min. The rapid cleareance of the gel observed after irrigation might provide a partial explanation of the minor effect of pocket irrigation on the subgingival microflora.