Search

Coronary artery disease ( CAD) is a major cause of death in the world. As a non-invasive imaging modality, computed tomography angiography ( CTA) is now usually used in clinical practice for CAD diagnosis. Precise quantification of coronary stenosis is of great interest for diagnosis and treatment planning. In this paper, a novel cluster method based on a Modified Student's t-Mixture Model is applied to separate the region of vessel lumen from other tissues. Then, the area of the vessel lumen in each slice is computed and the estimated value of it is fitted with a curve. Finally, the location and the level of the most stenoses are captured by comparing the calculated and fitted areas of the vessel. The proposed method has been applied to 17 clinical CTA datasets and the results have been compared with reference standard degrees of stenosis defined by an expert. The results of the experiment indicate that the proposed method can accurately quantify the stenosis of the coronary artery in CTA. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to compare the results of microbiological RNA-probe analysis after subgingival plaque sampling applying two different strategies. Methods: in 220 patients, clinical examinations were obtained prior to commencement of therapy for aggressive or generalized severe chronic periodontitis (n = 113), after combined mechanical and antibiotic anti-infective periodontal therapy (n = 43), or because of periodontal pockets despite adequate therapy (n = 64). Subgingival plaque samples were obtained from the three pockets with the deepest probing depths. Two sterile paper points were inserted simultaneously into the periodontal pockets. One paper point from each pocket was put into a separate transport vial; the second paper point was pooled (multiple site test [MT3]) with paper points from each of the two other sampling sites from the respective patient into a transport vial. The content of each vial was analyzed separately for Actinobacillus actinomycetemcomitans, Tannerella forsythensis, Porphyromonas gingivalis, and Treponema denticola (Td) with a commercially available RNA-probe test. Results: For all tested pathogens, log-transformed numbers of bacteria were higher in pooled samples compared to the mean values for the separate samples (P≤0.01). However, for Td only, statistically significant differences in frequency were seen between the separate samples and MT3. These findings were observed over all samples as well as after evaluation of subgroups separately. Conclusions: Pooling of plaque samples increased the bacterial counts per analysis compared to separate samples and thus may increase the probability of detecting existing pathogens. However, this observation only was statistically significant for the frequency of Td. [ABSTRACT FROM AUTHOR]

Untreated periodontal disease leads to tooth loss through destruction of the attachment apparatus and tooth-supporting structures. The goals of periodontal therapy include not only the arrest of periodontal disease progression, but also the regeneration of structures lost to disease where appropriate. Conventional surgical approaches (e.g., flap debridement) continue to offer time-tested and reliable methods to access root surfaces, reduce periodontal pockets, and attain improved periodontal form/architecture. However, these techniques offer only limited potential towards recovering tissues destroyed during earlier disease phases. Recently, surgical procedures aimed at greater and more predictable regeneration of periodontal tissues and functional attachment close to their original level have been developed, analyzed, and employed in clinical practice. This paper provides a review of the current understanding of the mechanisms, cells, and factors required for regeneration of the periodontium and of procedures used to restore periodontal tissues around natural teeth. Targeted audiences for this paper are periodontists and/or researchers with an interest in improving the predictability of regenerative procedures. This paper replaces the version published in 1993. [ABSTRACT FROM AUTHOR]

This paper was prepared by the Research, Science and Therapy Committee of the American Academy of Periodontology. It is intended to review the safety, efficacy, and role of sonic and ultrasonic sealers in mechanical periodontal therapy. The conclusions presented in this paper represent the position of the American Academy of Periodontology. This information is intended for use by the dental profession. [ABSTRACT FROM AUTHOR]

THE PURPOSE OF THIS PAPER is to provide a general overview of the role of supportive periodontal therapy in the treatment of periodontal diseases. Reliance on this position paper in patient management will not guarantee a successful outcome, as periodontal diseases typically involve numerous and complex causes and symptoms. Ultimately, decisions regarding the diagnosis, treatment, and management of disease, as well as subsequent preventive therapy, must be made by the treating practitioner based on the specific circumstances presented by that patient. [ABSTRACT FROM AUTHOR]

Hypertrophic cardiomyopathy (HCM) is a primary disease of cardiac muscle characterized by a thickening of the left ventricular wall and often predominantly affecting the interventricular septum. This paper presents a case study of a 53-year-old female with a dynamic and obstructive form of HCM. The study includes a case presentation, clinical findings, investigations, and management. Patient findings were obtained before and after alcohol septal ablation, a novel interventional therapy. The article reviews the various forms of HCM and describes the currently available treatment modalities for obstructive HCM. Further research will be necessary to determine the comparative efficacy between past, present, and future therapies. [ABSTRACT FROM AUTHOR]

Over the past 30 years, research has validated the success of osseointegrated implants as a viable alternative to fixed or removable prosthetic restorations. Periodontists are extensively trained in surgical procedures to treat and maintain patients with edentulous and partially edentulous arches. They also have a primary role in treatment planning and maintenance therapy. Thus, periodontists routinely integrate endosseous implants into periodontal therapy. This paper was prepared by the Research, Science and Therapy Committee of the American Academy of Periodontology and is intended to inform the dental profession regarding the utility of endosseous dental implants in the treatment of full and partial edentulism. [ABSTRACT FROM AUTHOR]

Background: An earlier publication from our laboratory described the use of guided bone regeneration to fill large bone voids in the mandible created through en bloc resection in primates. The present report is an embellishment of this paper and describes bone regeneration experiments in 18 adult male Macaca mulatta monkeys to determine how long membranes must be in position to promote guided bone regeneration. Methods: Thirty-six lesions were created in the mandibles of 18 monkeys in a standardized mandibular defect of 8 x 19 mm. Reinforced ePTFE membranes were placed in the animals and held in place with mini screws and sutures for anywhere from 1 to 12 months. No material was added to the defect. In addition to clinical studies, digital subtraction radiology and fluorescent labeling with tetracycline and histomorphometry are described. Results: The results indicate that no bone gain was observed in membranes exposed for 1 month or less, but bone gain (approximately well over 90% of defects) was observed at 12 months when membranes were left in situ for 2 to 12 months (P <0.0001). No significant difference in the amount of bone gained at 12 months was observed for membranes left in place for intervals ranging from 2 to 12 months. A significant correlation between the amount of bone gain observed at 3 and 12 months was observed (P <0.0001). Conclusions: Data therefore suggest that membranes left in situ for 1 month or less result in minimal bone gain compared with membranes left in place from 2 to 12 months. In addition, labeling and stained sections clearly showed that the bone produced after 2 months of membrane placement is mature. [ABSTRACT FROM AUTHOR]

Dens invaginatus is a well-known and well-established anomaly of development. Because it appears in various and complex forms, its diagnosis and treatment may be difficult. This paper presents different options based on anomaly variations, taking into consideration clinical and radiographic aspects as well as other criteria for treatment planning. [ABSTRACT FROM AUTHOR]

Traumatic intrusion of permanent teeth is a relatively infrequent but serious type of dental injury, due to the complicated picture it involves. Various treatment approaches have been suggested, so far, regarding management of intrusive luxation. Techniques aiming to reposition the intruded tooth include observation for spontaneous reeruption, surgical as well as orthodontic repositioning. However, development of complications such as pulp necrosis, inflammatory root resorption, replacement resorption and ankylosis and loss of marginal bone support makes selection of the most favorable technique controversial. In this paper, a critical review of the existing treatment modalities is attempted and treatment approaches based on diagnostic parameters that are indicative of the severity of an intrusive injury as presented. Recommendations are made after taking into consideration experimental and clinical study findings and observations form other author's and our own clinical experience. Two cases of intrusive luxation in children are presented and management of the dental injuries as well as the complications which occurred are being discussed. [ABSTRACT FROM AUTHOR]

This paper is a review and a discussion of our own pain research over the last decade. It is of a methodological and theoretical character and deals with preparation technique, choice of electrodes, control experiments involving pulpotomy and reliability tests of psychophysical methods for pain measurements, and the neuronal population encoding of sharp dental pain. The electrophysiological recording technique selectively picks up electrical activity induced in pulpal A-delta nerve fibers. The sensation of pain was quantified by means of an intermodal matching technique, finger span (PAS), in combination with sensory verbal descriptors covering a range from very, very weak to maximal pain. When a cold stimulus, ethyl chloride, was applied on the tooth surface a close agreement was demonstrated between intradental A-delta nerve activity (INA) and the sensation magnitude of pain (PAS) with respect to curve amplitude and time course. The high covariation of the neural and perceptual response measures indicated a good internal validity and confirmed also the basic soundness and the applicability of the procedures employed. For the purpose of further analyzing the functional relation of INA to PAS we studied specifically the effect of cold stimuli of different intensity on the integrated nerve response. Only sharp, shooting pain was accepted as a sensorial, perceptual correlate of the intradental A-delta nerve activity. Since an increase in amplitude was generally accompanied by an increase in duration of the responses, the fundamental question was raised how to best describe and characterize the neural and perceptual responses so that they most adequately reflect the information processing of the intensive aspect of sharp dental pain. Three response criteria were used: average response amplitude of INA per second, (ii) peak amplitude of INA and (iii) integral of INA, i.e. the total activity over time. [ABSTRACT FROM AUTHOR]

The development of an automatic system which, as a means of treatment, can control the blood pressure of a patient by a continuous injection of vaso-acting drugs is in great demand in the medical care field. However, the practical application of such a system has been postponed due to safety considerations. This paper attempts to realize the safe control of the physiological system, and a control method based on the recognition of the transition of the time-series signal has been developed. The idea is applied to the automatic control of blood pressure. For the recognition of the time-series signal transition, a dedicated IF-THEN representation TMSTR (time-sequential multiple state transition representation) is devised which includes the concepts of "state" and "time." [ABSTRACT FROM AUTHOR]

This article presents a study which focuses on the role of tetrahydrobiopterin within the cell in the therapy and management of malignant hyperphenylalaninaemia and other neurological illnesses. Malignant hyperphenylalaninaemia is found in about 1 % of cases of phenylketonuria. It may be a model for the understanding and therapy of other neurological disorders. The data presented in this paper suggest that in man tetrahydrobiopterin synthesis can be increased by simultaneous administration of ascorbate, hydroxocobalamin and 5-substituted tetrahydrofolates such as folinic acid and 5-methyltetrahydrofolate.