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81.
82.
The growth of dental plaque on different materials 总被引:1,自引:0,他引:1
C H Berthold P Berthold P O S?der 《Svensk tandl?kare tidskrift. Swedish dental journal》1971,64(12):863-877
83.
Alpöz E Güneri P Onder G Cankaya H Kabasakal Y Köse T 《Clinical oral investigations》2008,12(2):165-172
Sjögren syndrome (SS) is a chronic inflammatory autoimmune disease of unknown cause whose main characteristic is severe dryness of the eyes and the mouth. The decreased functional capacity of the lacrimal and salivary glands which is the result of the inflammatory process and lymphocytic infiltration observed in SS is accountable for this complication. Twenty-nine patients with SS whose ages were ranging between 24–77, who were under treatment in Ege University Faculty of Medicine Department of Rheumatology, participated in the study, and their informed consents were obtained upon enrollment. Each patient recorded their subjective complaints on a separate questionnaire. The baseline and subsequent evaluation of the subjective findings on predetermined times (1 h after application of the material, at the end of the 1st, 7th, and 14th days) were also recorded on separate questionnaire sheets. Throughout the 14-day treatment period, no statistically significant differences were noted between the Xialine® and placebo groups with regard to burning tongue, diminished taste, and waking up at night to sip water (p?=?0.925, 0.527, and 0.066, respectively). However, patients’ satisfaction with placebo decreased by 25.63% at the end of the test period, whereas it increased by 16.37% after Xialine® administration. Overall, the patients preferred Xialine® at the end of the study (p?=?0.011). The main motive to administer saliva substitute is to improve lubrication and hydration of oral tissues. The results of this study indicated that Xialine® is helpful in the management of xerostomia-related symptoms of SS patients. However, further investigations in larger scale group of patients are recommended to provide the effects of these agents on various complaints of xerostomia. 相似文献
84.
The effectiveness of the parasympathetic denervation of the gland caused by avulsion of the auriculo-temporal nerve was investigated. In the first type of experiment, the cholinesterase inhibitor, eserine, was injected through the salivary duct. The substance is thought to preserve acetylcholine leaking from nerve endings, thereby causing secretion of saliva; a secretory response was thus taken as evidence for the presence of cholinergic nerves. In the second type of experiment, the acetylcholinesterase activity of the gland was examined histochemically. From the denervated glands, eserine caused secretion and acetylcholinesterase positive nerves were found in the glands. Both the amount of secretion and the number of nerves were greatly diminished when compared with the intact glands. The results indicate that the denervation procedure was incomplete, leaving some cholinergic nerves unsevered. That cholinergic nerves remain offers an explanation to the residual choline acetyltransferase activity, which has earlier been shown in the gland after avulsion of the auriculo-temporal nerve. To extend the denervation procedure, either avulsion of the facial nerve or avulsion of the superior cervical ganglion was included. Neither procedure abolished the response to eserine or the acetyl-cholinesterase activity, indicating that the routes for the remaining nerves are to be found elsewhere. 相似文献
85.
PURPOSE: To evaluate the capacity of a novel oral water irrigator to remove established plaque deposits. METHODS: The study was designed as a randomized two-treatment, crossover, examiner-blinded clinical trial. The plaque removing capability of a prototype oral irrigator was compared to a conventional electric toothbrush. After 48 hours of plaque accumulation the 35 subjects were randomly assigned to professional plaque removal by either oral irrigation or by electric toothbrushing for a timed 2-minute total cleaning. Pre- and post cleaning plaque was disclosed and gingival abrasions were identified. Plaque was assessed on gingival and approximal surfaces of the oral and buccal sites according to the Rustogi et al modification of the Modified Navy Plaque Index. The assessment of gingival abrasions was performed according to the method introduced by Danser et al. RESULTS: The overall plaque removing capacity of the oral irrigator reached approximately 40.7 +/- 16.7% as compared to 71.6 +/- 11.5% by the electric toothbrush. Similar effects were observed for the gingival and approximal areas. The electric toothbrush caused significantly more gingival abrasions than the oral irrigator. 相似文献
86.
Jepsen S Heinz B Jepsen K Arjomand M Hoffmann T Richter S Reich E Sculean A Gonzales JR Bödeker RH Meyle J 《Journal of periodontology》2004,75(8):1150-1160
BACKGROUND: The objective of this multicenter, randomized trial was to compare enamel matrix derivative (EMD; test) with barrier membranes (control) for the treatment of mandibular buccal Class II furcation defects. METHODS: Forty-five patients with 90 comparable defects on contralateral molars were included. Defects were randomly assigned to EMD or bioabsorbable barrier membrane; the contralateral defect received the alternative treatment. Assessments at baseline and 8 and 14 months included gingival margin levels, probing depths, bleeding on probing, vertical attachment levels, and vertical bone sounding from a stent at five buccal sites/ tooth. Defect dimensions were recorded at surgery and during reentry at 14 months. Change of open horizontal furcation depth was the primary outcome variable. Adverse reactions and patient perceptions were also noted. RESULTS: Both treatment modalities led to significant clinical improvements. The median reduction of open horizontal furcation depth was 2.8 mm with the corresponding interquartile interval (1.5 mm, 3.5 mm) at test sites compared with 1.8 mm (1.0 mm, 2.8 mm) at control sites. The Hodges-Lehmann estimator of the advantage (reduction test versus control) was 0.75 mm (95% confidence interval [CI]: 0.125 mm, 1.375 mm, P = 0.033, Wilcoxon). The frequency of complete furcation closure was 8/45 (test) and 3/45 (control); partial closure, 27/45 in both groups; no change, 9/45 and 11/45, respectively; and deterioration, 1/45 and 4/45, respectively. The frequency of no pain or no swelling at 1 week post-surgery was 62% and 44%, respectively, at the test sites and 12% and 6% at the control sites. CONCLUSION: There was a significantly greater reduction in horizontal furcation depth and a comparatively lower incidence of postoperative pain/swelling following enamel matrix derivative compared to membrane therapy. 相似文献
87.
It is known that surface morphology greatly influences the osseointegration of dental implants. The goal of the experiments conducted by the authors was to study in vitro the effect of various surface modifications on the activity of bone and connective tissue cells. In the experiments they introduced NIH3T3 fibroblast and MCH3T3 osteoblast cells were cultured the surface of ten titanium disks with various morphology in 24-multiwell plates. The cells were let grow on the surface of the disks for two days in a culture medium. One group of the disks underwent scanning electronmicroscopy and the changes in the number and form of cells on the surfaces were studied under various magnifications. From the surface of the second group the cells were lysed and were counted in a Bürker's chamber. After counting the cells they were lysed in a lysis buffer and their protein concentrations were measured with the help of a spectrophotometer. The authors found that only a morphological study of the cells is possible under SEM, they could not detect a quantitative difference in the number or activity of the cells. Upon counting the cells and determining their protein concentration the best result were yielded by the surface roughened by aluminium oxide. In growing fibroblasts the titanium oxide treated surfaces provided good results, while in the case of the osteoblasts the laser treated disks were more successful. 相似文献
88.
Moreira CH Fiorini T Ferreira E Antoniazzi R Rösing CK 《Acta odontológica latinoamericana : AOL》2007,20(1):33-37
The aim of the present study was to determine the percentage of dentists who use radiographic examination on the initial appointment, and establish the relation between the use of periodontal probe and graduation year. Dentists were interviewed in their private offices in three cities in Rio Grande do Sul. They were asked about the routine use of radiographic examination and, if applicable, what technique was applied and what clinical instrument was used at the first appointment. Opened and closed questions were included in the interview and for some of them more than one answer was possible. A significant number of dentists (62.9%) reported some kind of radiographic examination at the initial appointment. Among the radiographic techniques, the periapical was the most cited (74.3%), followed by the panoramic (36.2%) and bite-wing (32.9%) techniques. There was an association between the use of periodontal probe and the use of radiographic examination at the initial appointment. Dentists who used periodontal probe used radiographic examination more frequently (p=0.010). More recently graduated dentists (1991-2005) used radiographic examination more than the others (p=0.022). In conclusion, a large number of dentists reported the use of radiographic examination at the initial appointment. There was an association between the use of this examination technique and the use of the periodontal probe; recently graduated dentists used radiographic examinations more frequently than the others. 相似文献
89.
The objective of this study was to compare the cytotoxic effects of a calcium aluminate cement with several currently used direct restorative materials. Specimens of three composites (QuiXfil, Tetric Ceram, Filtek Supreme), one zinc phosphate cement (Harvard Cement), one glass ionomer cement (Ketac Molar), and one calcium aluminate cement (DoxaDent), were used fresh or after 7-days' preincubation in cell culture medium at 37 degrees C, pH 7.2. PVC strips for ISO 10993-5 cytotoxicity test were used as positive control and glass specimens as negative control. L-929 fibroblasts (5-ml aliquots, containing 3 x 10(4) cells/ml), cultivated in DMEM with 10% FCS, 1% glutamine, and 1% penicillin/streptomycin at 37 degrees C/5% CO2 and trypsinized, were exposed to the specimens for 72 h. The cells were harvested, centrifuged, and resuspended in 500 microl DMEM and then counted in 500 microl DMEM for 30 s with a flow cytometer at 488 nm. The analysis of variance comparing the six materials showed different influences on L-929 fibroblast cytotoxicity (p <0.0001). The cytotoxicity of all specimens diminished with increasing preincubation time (p <0.0001). Fresh DoxaDent exhibited the lowest cytotoxicity, followed by QuiXfil. Ketac Molar showed the highest cytotoxicity. After 7 days of preincubation, Harvard Cement and Filtek Supreme demonstrated more cytotoxicity than the other materials (p <0.005). 相似文献
90.
OBJECTIVE: Pharmaceuticals are among factors that might be associated with temporomandibular disorders (TMDs), but knowledge about their utilization is limited. The purpose was to systematically register the regular use of medication in general among TMD patients and matched controls to enable comparisons to be made. MATERIAL AND METHODS: Three hundred consecutive patients referred for diagnosis and treatment of TMDs and fulfilling the Research Diagnostic Criteria were examined prospectively and any medication recorded. Matched controls were registered parallel in time. The pharmaceuticals used were categorized according to the Anatomical Therapeutic Chemical Classification System (ATC). RESULTS: Forty-four percent of the patients received a main diagnosis of "muscle disorder", 39% "disk disorder", and 17% "joint disorder". Fifty-one percent of all patients used some medication on a regular basis compared to 36% of the controls (p<0.001). The average number of ATC categories used among all patients was 0.9 and among controls 0.5 (p<0.001). Of the female patients with the diagnosis "muscle disorder", 23% used antidepressants (N06A), 6% tranquilizers (N05B), and 7% sleep medication or sedatives (N05C) significantly more frequently than controls. Of the female patients diagnosed with a "joint disorder", 26% used antidepressants (N06A) significantly more frequently than controls. All other ATC categories differed non-significantly. CONCLUSIONS: The results suggest that the use of pharmaceuticals differs between patients and controls. TMD patients, particularly women diagnosed with "muscle" or "joint" disorders, appear to use drugs for depression more frequently than ordinary dental patients. 相似文献