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11.
A total of 85 Finnish alcohol-dependent subjects and 53 controls were studied with panoramic radiography. The aim was to study the possible associations between prolonged alcohol consumption and dental health. The mean number of teeth, caries lesions, endodontic treatments, periapical lesions, marginal bone loss, and periodontal infrabony pockets was studied. The subjects met the diagnostic criteria of alcohol dependence as set out in DSM-IV and ICD-10. The control group comprised social drinking volunteers with an AUDIT score < or =8. For the final results the subjects were divided into groups on the basis of sex and age. The social backgrounds of the subjects were similar, except for employment and smoking. The results show significantly fewer teeth and more caries in the alcoholic group. There was a tendency for the alcoholics <45 years of age to have more endodontically treated teeth than the controls, but no difference in the number of periapical lesions in endodontically treated teeth was found. Horizontal bone loss and the presence of calculus were more frequent in alcoholic men than in alcoholic women. Significantly more horizontal bone loss was observed in the group of alcoholic nonsmokers than in nonalcoholic nonsmokers. In the nonsmoking groups alcoholics had significantly more periodontal destruction than the nonsmoking controls. We conclude that radiological dental health among individuals dependent on alcohol is weakened by more caries, more horizontal bone loss, and more numerous vertical infrabony pockets than social drinkers.  相似文献   
12.
Interleukin-6 (IL-6)-type cytokines are pleiotropic molecules capable of stimulating bone resorption and expressed by numerous cell types. In the present study, we tested the hypothesis that gingival fibroblasts may exert local osteotropic effects through production of IL-6 and related cytokines. IL-6-type cytokine expression and regulation by IL-1beta and tumor necrosis factor-alpha (TNF-alpha) were studied in fibroblasts from the non-inflamed gingiva of healthy individuals. Constitutive mRNA expression of IL-6, IL-11, and leukemia inhibitory factor (LIF), but not of oncostatin M (OSM), was demonstrated, as was concentration-dependent stimulation of IL-6 and LIF mRNA and of protein by IL-1beta and TNF-alpha. IL-11 mRNA and protein were concentration-dependently stimulated by IL-1beta. The signaling pathway involved in IL-6 and LIF mRNA stimulation involved MAP kinases, but not NF-kappaB. The findings support the view that resident cells may influence the pathogenesis of periodontal disease through osteotropic IL-6-type cytokine production mediated by activation of MAP kinases. Abbreviations: IL-1alpha (interleukin-1alpha); IL-1beta (interleukin-1beta); IL-6 (interleukin-6); IL-11 (interleukin-11); LIF (leukemia inhibitory factor); OSM (oncostatin M); alpha(1)-coll. I (alpha(1)-collagen I); ALP (alkaline phosphatase); BMP-2 (bone morphogenetic protein-2); OC (osteocalcin); BSP (bone sialoprotein); TNFR I (tumor necrosis factor receptor I); TNFR II (tumor necrosis factor receptor II); IL-1R1 (interleukin-1 receptor 1); GAPDH (glyceraldehyde-3-phosphate dehydrogenase); RPL13A (ribosomal protein L13A); mRNA (messenger ribonucleic acid); cDNA (complementary deoxyribonucleic acid); PCR (polymerase chain-reaction); BCA (bicinchoninic acid); ELISA (enzyme-linked immunosorbent assay); alpha-MEM (alpha modification of Minimum Essential Medium); and FCS (fetal calf serum).  相似文献   
13.
OBJECTIVE: It was the aim of the present study to investigate the material properties of different resins and their suitability for the fabrication of occlusal and intermaxillary splints. MATERIAL AND METHOD: We subjected auto-polymerized resins (Palapress, Orthocryl, Steady-Resin M) and light-polymerized resins (Acrylight, Primosplint, Triad TranSheet Colorless and Pink) to investigation. The Targis Power light oven was used to polymerize the light-cured resins. After the auto-polymerized resins had been mixed by hand and filled into the forms, they were polymerized for 15 minutes in a high-pressure polymerization machine (Palamat) at 2 bar. The parameters examined were flexural strength, water adsorption, and polymerization shrinkage. Tests carried out according to DIN EN ISO 1567 served to determine flexural strength, flexural modulus, and water adsorption. Polymerization shrinkage was determined via the buoyancy test. RESULTS: The resins' flexural strength ranged from 60 to 101 MPa. Flexural moduli lay between 1.3 and 5.3 GPa. The water adsorption noted in light-cured resins amounted to 2.1-4.6 mass percent. Palapress and Steady-Resin displayed the lowest water adsorption with 2.0 mass percent. The light-polymerized resins revealed significantly less shrinkage (p < 0.05) than the autopolymerized resins tested in this study. CONCLUSION: Our results demonstrate that the light-cured resins-with the exception of Acrylight -easily match and even exceed the material properties of the cold-polymerized resins regarding flexural strength, flexural modulus, water adsorption and polymerization shrinkage. The light-cured resins examined thus seem suitable for use as splint material.  相似文献   
14.
15.
AUTHORS: Shen G, Hagg U, Darendeliler MA. OBJECTIVE: Based on an extensive review of the literature, the aim of this study was to explore the mainstream consensus on the controversial topic of whether the bite jumping treatment could enhance mandibular growth. DESIGN: The data for removable and fixed functional appliances were respectively comprehended and analyzed with regard to their attributes in mandibular growth modification. Furthermore, numerous reported findings were assessed by relating them to some important factors influencing the effects of bite jumping, such as treatment timing, treatment duration and post-treatment follow-up, to allow for a more objective and accurate evaluation. RESULTS: The key differences between removable and fixed appliances are working hours (intermittent vs. continuous), length of treatment time (long vs. short), optimal treatment timing (before puberty growth vs. at or after puberty spurt), and mode of bite-jumping (considerable vertical opening vs. limited vertical opening). These different features lead to different treatment effects on mandibular and TMJ growth, such as the intensity of possibly increased growth (clinically less significant vs. significant), the direction of enhanced growth (vertical vs. horizontal), and the stability of treatment changes (unstable vs. stable). The short-term or long-term post-treatment relapse mainly relates to the rebound of dental position. CONCLUSION: The immediate effects of bite jumping functional appliances on the mandibular growth enhancement are convincing during actual treatment. This extra gain of growth might be sustainable during the short-term and long-term post-treatment period.  相似文献   
16.
AIM: To study the presence, levels and molecular forms of matrix metalloproteinase (MMP) -8 (collage-nase-2) in pulpal and periapical inflammation, and the changes in MMP-8 levels in root-canal exudates during root-canal treatment. METHODOLOGY: Periapical exudate samples were collected from 11 necrotic teeth with radiographically verified periapical periodontitis during three root-canal treatment visits with interappointment calcium hydroxide (Ca(OH)2) medication. MMP-8 levels and molecular forms were analyzed with immunofluorescent assay (IFMA) and Western immunoblot. Inflamed pulp tissue and periapical granuloma tissue (n = 10 for both) were obtained from other patients and used for MMP-8 immunohistochemical (IHC) staining. RESULTS: The periapical exudate samples demonstrated marked differences in MMP-8 levels between the teeth in the first visit and significant decrease in MMP-8 levels during the root-canal treatment (P = 0.0107). One specimen failed to show a decrease in MMP-8 below 1000 ng mL(-1) a vertical root fracture was later diagnosed and the tooth extracted. IHC staining showed that in addition to PMN-leucocytes, macrophages and plasma cells produced MMP-8 in pulp and periapical granulomas. CONCLUSIONS: The findings demonstrate the presence of MMP-8 in the inflamed pulp and periapical tissue, indicating that MMP-8 has a role in pulpal and periapical inflammation, most likely participating in tissue extracellular matrix degradation. They further indicate that MMP analysis from periapical exudate could be used to indicate and monitor inflammatory activity and the success of treatment in teeth with periapical lesions.  相似文献   
17.
18.
Zusammenfassung Zu jeder Ober- und Unterkieferplatte gehören Halte- und aktive Elemente. Die Plattenkörper sollen grazil konstruiert sein. Das ist nur möglich, wenn auch die Drahtanteile entsprechend gebogen werden, ihre Anzahl klein ist und sie vielseitig gebraucht werden können. Halteelemente müssen gegebenenfalls auch aktive Elemente sein können und umgekehrt ebenso. Dabei ist besonders zu beachten, daß die Halteelemente den Verankerungsverlust so klein wie möglich halten. Besonders geeignete Halteelemente für die Zähne der 1. und der 2. Dentition sowie die des Oberkiefers und Unterkiefers werden demonstriert (Dreiecksklammer,Adams-Klammer, Auflage). Die aktiven Elemente sind der Labialbogen und Schrauben. Ein größerer Aufwand ist in der Mehrzahl der Fälle nicht nötig. Behandlungsabläufe mit Plattenapparaten dieses Konstruktions- und Wirkungsprinzipes verdeutlichen die Vorstellungen.
Summary Every maxillary and mandibular plate consists of active and passive elements. The acrylic base should be as small as possible. This is only possible if the wires are bent correctly, if there are not too many of them and if they can be used in several ways. Cribs need to be active elements as well as passive ones. It is very important that the cribs keep the loss of anchorage to a minimum. Cribs found to be specially useful in the 1st and 2nd dentition as well in the upper as in the lower jaw are described (triangular crib,Adam's crib, occlusal rest). Screws and labial arches are used as active elements. The construction of the appliances and the treatment procedures are described.

Résumé Chaque plaque supérieure et inférieure possède ses crochets actifs et de rétention. La base acrylique ne doit pas être trop grande. Les fils métalliques doivent être construits correctement, ne pas être trop nombreux et pouvoir servir aussi bien comme crochets actifs que de rétention. La perte d'ancrage des éléments de rétention doit être la plus petite possible. Les crochets triangulaires, d'Adams et la rétention de résine sur la face occlusale sont valables pour les deux maxillaires et aussi bien pour la première que pour la seconde denture. On mentionne comme éléments actifs, l'arc vestibulaire et le vérin. D'autres éléments ne sont pas nécessaires dans la plupart des cas. Finalement on présente des cas traités avec des plaques élaborées selon ces principes.


Meinem ehemaligen Assistenten, Herrn Dr. A. Häusler, danke ich besonders für die instruktiven Zeichnungen.  相似文献   
19.
Dentinhaftmittel     
P. Städtler 《Stomatologie》2007,104(4):101-109
  相似文献   
20.
OBJECTIVE: The aim of the present study was to determine the surface hardness of light- and auto-cured resins for the fabrication of occlusal splints employing Vickers hardness measurements. MATERIALS AND METHOD: In this study we used three auto-polymerized resins (Palapress, Orthocryl, Steady-Resin M) and four light-polymerized resins (Acrylight, Primosplint, Triad Tran- Sheet Colorless and Triad TranSheet Pink). The Vickers hardness measurement was carried out by means of a universal Durimet indenter applying a test load of 50 g for 30 seconds. The light-cured resins were polymerized in a Tagris Power light oven for 10 and 15 minutes each. Three separate test series were carried out (the hardness of plates under optimal conditions and of occlusal splints was measured, and the curing of light-polymerizing materials in layers of varying depth was evaluated). Data underwent statistical analysis via ANOVA and the Scheffé test. RESULTS: The microhardness determined in each case amounted to values between 10.4 HV 0.5 and 39.3 HV 0.5. The Vickers hardness determined for the plates that had been produced under optimal conditions demonstrated that their surface was significantly (p < 0.05) harder than that of cylinders and splints. The hardness values of the light-cured material Triad TranSheet Pink (39.3 HV 0.5) were significantly higher (p < 0.05) than those of all other resins. In all auto-polymerized resins, the surface hardness of the samples we examined (in the form of plates and splints) was significantly lower (p < 0.05) than that of the light-cured materials Triad TranSheet Pink and Colorless. CONCLUSION: The results we have obtained so far concerning surface hardness indicate that, in the fabrication of occlusal splints, light-cured resins may represent an alternative to auto-polymerizing materials.  相似文献   
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