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41.
Assessment of denture satisfaction   总被引:2,自引:0,他引:2  
The aim of this investigation was to evaluate the reliability and validity of a complaints questionnaire, designed to measure different aspects of denture satisfaction. Two groups of patients with full maxillary and mandibular dentures participated in the study. The patients in Group 1 (n = 113) were on a waiting list for new dentures, patients in Group 2 (n = 102) had recently had new dentures fitted. Five denture complaint scales were constructed from the questionnaire. The internal consistency (coefficient alpha) of the scales varied from 0.65 to 0.92. Furthermore, the scales showed a discriminatory ability between the patient groups (P less than or equal to 0.001) and significant Pearson correlation coefficients with satisfaction-related questions (r = 0.25-0.79). The scores on the scales can be considered a quantitative measure of denture satisfaction.  相似文献   
42.
We tested the null hypothesis that there is no difference in the sealing ability of GuttaFlow, RoekoSeal, and AH26 in root canals. Sixty extracted mandibular premolars were filled with AH26 (lateral compaction), RoekoSeal, or GuttaFlow (modified single-cone). The sealing ability of the root canal fillings was measured weekly (4 weeks) by using a glucose penetration model. Kruskal-Wallis test revealed significant differences in glucose penetration between the experimental groups at weeks 1, 2, 3, and 4. Whereas GuttaFlow showed the highest amount of leakage at all times, AH26 showed the lowest. There was no significant difference between RoekoSeal-filled and AH26-filled root canals throughout the experimental period. AH26 showed better sealing ability in root canals than GuttaFlow.  相似文献   
43.
Purpose: To investigate photoelastically the difference in load distribution of dental implants with different implant neck designs in intact and compromised bone. Materials and Methods: Composite photoelastic models were fabricated using two different resins to simulate trabecular bone and a 1‐mm thick layer of cortical bone. The following parallel‐sided, threaded implants were centrally located in individual models representing intact and compromised cortical bone: Straumann (4.1‐mm diameter × 12‐mm length), AstraTech (4.0‐mm diameter × 13‐mm length), and 3i (3.75‐mm diameter × 13‐mm length). The compromised cortical bone condition was simulated by contaminating a 1‐mm neck portion with Vaseline to impair the implant–resin interface. Vertical and oblique static loads were applied on the abutments, and the resulting stresses were monitored photoelastically and recorded photograhphically. Results: For the fully intact condition, the highest stresses were observed around the crest and apical region for all implant designs under vertical and inclined loads. There were no appreciable differences in magnitude or distribution between implant types. With compromised cortical bone, for all designs and load directions, higher stresses in the supporting structures were observed. Increased stresses were noted especially at the cortical bone–trabecular bone interface. Somewhat lower stress levels were observed with the 3i implant. Conclusions: The condition of implant–cortical bone contact has considerable influence on stress distribution. A compromised cortical bone condition caused higher level stresses for all implant designs tested.  相似文献   
44.
OBJECTIVE: Pre-eclampsia is a complication of pregnancy characterized by systemic vascular dysfunction and pathological changes in placental arteries. Growing evidence of chronic infection as an aetiological factor in vascular diseases prompted us to study maternal periodontal disease in subjects with early-onset pre-eclampsia (<34 weeks). METHODS: A case-control study was carried out on 17 early-onset pre-eclamptic women and 35 controls with uncomplicated pregnancies in a period of 3-28 months postpartum. All were Caucasians. Full-mouth periodontal examinations were performed to determine the periodontal condition. Subgingival-plaque samples were analysed by anaerobic culture techniques for the presence of seven bacterial periodontal pathogens. Potential confounders as age, smoking, educational level and body mass index were determined. RESULTS: Severe periodontal disease was found in 82% of the pre-eclamptic and in 37% of the control group (p=0.009). After adjusting for age, smoking and educational level, the odds ratio was 7.9 (95% CI: 1.9-32.8). The periodontopathic microorganism Micromonas micros was more prevalent in the case group (p=0.040) while Campylobacter rectus was more prevalent in the control group (p=0.047). CONCLUSION: These results indicate that Caucasian women with a recent history of early-onset pre-eclampsia have a worse periodontal condition, as compared with women with uncomplicated deliveries.  相似文献   
45.
A study has been conducted to assess the oral health status and need for dental treatment among elderly Cape Coloreds resident in homes for the aged in the Cape Peninsula of South Africa. This paper describes the prevalence of diseases of the mouth with special reference to denture-induced lesions and white lesions of the oral mucosa. Dental caries was the most prevalent oral lesion (27.2%). The most common conditions of the soft tissues were leukoedema (24.4%) and leukoplakia (4.4% for the tongue; 20.4% for the remainder of the oral mucosa). Leukoedema and leukoplakia showed statistically highly significant correlations with tobacco habits. Men more commonly had a tobacco habit than women (P less than 0.002) and leukoplakia, leukoedema and depigmented lesions of the lips were significantly more common in men than in women. No significant difference could be proven statistically when the frequency of irritative fibrous hyperplasia in females was compared with that in males.  相似文献   
46.
The fermentation products of Streptococcus mutans C67-1 were investigated in fissure plaque of rats, that were mono-associated with this strain. In addition to lactic acid, acetic acid and ethanol were present. The finding that a mixed acid fermentation occurred and that ethanol was produced suggests that the carbohydrate source rather than the nitrogen source was the growth-limiting substrate for Strep. mutans in plaque.  相似文献   
47.
Atraumatic restorative treatment (ART) is an approach to the management of carious lesions that uses only hand instruments to remove carious tissue and to restore the tooth involved. The name ART implies that the approach is atraumatic to both the patient and the tooth. This study set out to evaluate whether ART is atraumatic in terms of both patient discomfort and tooth tissue conservation. Three hundred and fifty-nine patients were divided in two groups: one group was treated with hand instruments and the other with rotary equipment. Each patient received two restorations: one using amalgam and one using glass ionomer as the restorative material, placed without the use of anaesthesia. Less discomfort was reported with the ART approach compared to conventional restorations made using rotary instruments and amalgam. Moreover, preparations with hand instruments were smaller than those produced with rotary instruments. Reported discomfort was associated with the size of the preparation, although the influence of the operator on both criteria was considerable. A patient effect was also observed since patients who reported discomfort during the first treatment were more likely to report discomfort after the second treatment. In conclusion, the choice of the term "ART" as an atraumatic procedure is defensible.  相似文献   
48.
Shoulder complaints after nerve sparing neck dissections   总被引:1,自引:0,他引:1  
The purpose of the study was to analyse the prevalence of shoulder complaints after nerve sparing neck dissection at least 1 year after surgery, and to analyse the influence of radiation therapy on shoulder complaints. Patients were interviewed for shoulder complaints, and patients filled out the shoulder disability questionnaire to evaluate shoulder disability in daily activities. In total 137 patients; 51 after modified radical neck dissection (MRND), 21 after postero-lateral neck dissection (PLND), and 65 after supraomohyoid neck dissection (SOHND) were analysed. After MRND 33.3% of the patients experienced shoulder complaints, after PLND 66.7%, and after SOHND 20% of the patients experienced shoulder complaints. Type of neck dissection was significantly (P < 0.001) related to shoulder complaints. Outcome on the shoulder disability questionnaire also showed a significant (P < 0.01) difference in outcome for type of neck dissection. The prevalence of shoulder complaints after SOHND are low, and reduce disability in daily activities. Radiation therapy does not have a significant effect on shoulder complaints and disability.  相似文献   
49.
50.
OBJECTIVE: To assess the effect of varying CaF(2) on the chemical solubility of apatite-mullite glass-ceramic (G-C) materials in both the glassy and crystallized states. METHODS: Apatite-mullite forming glasses used in this study are ionomer cement derivatives based on the general formula (4.5SiO(2)-3Al(2)O(3)-1.5P(2)O(5)-3CaO-XCaF(2)). Six glass formulations were produced where X=0.5, 1, 1.5, 2, 2.5 and 3, and called HG1-6, respectively. Batches were melted in covered silliminite crucibles in a furnace overnight at 1050 degrees C, then at 1450 degrees C for 2h, before quenching in water. The six glass compositions were analyzed using differential thermal analysis (DTA), X-ray diffraction (XRD) and X-ray fluorescence spectrometry (XRF). Thirty discs (2mm thick and 12 mm diameter) were produced per glass using the lost wax casting technique. Ten were left as cast and 10 heat treated to either apatite or apatite-mullite. Solubility testing was carried out according to International Standard BS EN ISO 6872 1999 and the mass difference in solubility calculated as mug/cm(2). A lithium disilicate G-C system was used as a control material. RESULTS: All compositions formed glasses and on heat treatment could form apatite and apatite-mullite. The as-cast glass samples were the most soluble followed by the apatite samples. The apatite-mullite G-C was significantly less soluble than the other two phases (p<0.05) for all six compositions. The control material was significantly less soluble than all the HG glass-ceramic compositions for every phase (p<0.05). Decreasing the CaF(2) content (3-0.5 mol%) led to a decrease in solubility, without affecting the ability of the material to form apatite and apatite-mullite phases. SIGNIFICANCE: Increasing the CaF(2) content increases the chemical solubility for the glass, apatite G-C and apatite-mullite G-C phases. The solubility values obtained show that all the compositions, as cast and heat treated would be suitable for use as core ceramics.  相似文献   
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