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961.
962.
Treatment of osteitis in the mandible after surgery is still a clinical problem. Levels of four antibiotics--azidocillin, erythromycin, doxycycline, and clindamycin--were measured in serum and dental alveolar serum in 42 patients undergoing oral surgery. The systemic serum concentrations were higher than the dental alveolar serum concentrations in all patients. The maximal concentration in the alveolar serum for azidocillin was 6.0-12.0 microng/ml, for erythromycin 0.7-1.3 microng/ml, for doxycycline 2.8-3.6 microng/ml, and for clindamycin 2.0-2.8 microng/ml. When the dental alveolar serum concentrations of the various antibiotics were related to their range of inhibitory concentrations for microorganisms isolated from mandibular osteitis, it was noticed that each drug achieved levels sufficient to inhibit most strains.  相似文献   
963.
964.
The water permeability of the human palatal mucosa has been studied in 12 persons with 1 year of full maxillary denture experience and 10 persons without dentures. Transmucosal water transport rates were studied gravimetrically with the use of solutesaturated discs of filter paper in contact with the mucosa, in accordance with earlier described procedures (KAABER 1973a, b). The inflow of water through clinically healthy mucosa was at the same level in both groups. After use of a 1.10 mol sucrose solution a significant increase in the inflow was observed in the denture wearers group, which suggested an increased amount of osmolytes in the mucosal surface. Two denture wearers with a slightly inflamed mucosal surface showed an increased inflow after use of water and a corresponding strong outflow after use of the sucrose solution, indicating a partial loss of the mucosal barrier function.  相似文献   
965.
The site of collagenase production in explants of bovine gingiva was located by tissue culture techniques. Collagenase was released from the juxta-epithelial connective tissue, but not from the epithelium. Addition of serum to the explants resulted in outgrowth of a single cell type, which was identified as a fibroblast on the basis of culture morphology and light and electron-microscopic characteristics. The fibroblasts elaborated a collagenase that was indistinguishable from the enzyme harvested from whole bovine gingival explants. The enzymes, both of which were released in latent form, had the same molecular size and had common antigenic sites.  相似文献   
966.
Dietary protein restriction adversely affects mandibular growth in the weanling rat. Protein deficiency is usually accompanied by reduced food intake which, in turn, induces energy deficiency. The present study was thus designed to dissociate the effects of dietary protein and energy deficiencies on the growth of the mandible in rapidly growing rats. Four groups of Sprague-Dawley rats aged 30 days were fed a normal diet, a low-energy diet, a low protein diet, and a low-protein and low-energy diet for 20 days. Rats were sacrificed at the end of experimental period and body weight and mandibular dimensions were recorded to evaluate body growth and mandibular growth. The growth of the mandible was affected almost in the same order of magnitude by both protein and energy restrictions. When both were applied together, mandibular growth was even more severely affected. Two way analysis of variance revealed the absence of synergism between variables, indicating that the negative effects of dietary protein and energy restrictions on mandibular growth could be considered to be additive.  相似文献   
967.
The study was conducted in seven schools on children initially aged 11.5 years. They recorded their diet on five occasions, each of three days, and received an annual dental examination, including radiography. Caries increments were low, mostly (58 per cent) in fissure surfaces. Correlations between caries increment and dietary factors were low due to the low caries increments observed and the large error associated with dietary data where analyses attempt to discriminate between individuals. The highest correlation was between caries increment and weight of daily intake of sugars (+ 0.143, p < 0.01). Multivariate analyses revealed that this relationship could not be explained by differences in sex, social class, tooth-brushing habits or level of plaque as measured by gingival inflammation. Weight of sugar intake appeared to be more strongly correlated to caries than frequency of intake; concentration of sugars in foods was positively related, and sugars in snacks were more strongly related to caries than total dietary sugars. The 31 children who consumed most sugar (> 163 g/day) developed 5.0 DMFS during the 2 years, 0.9 DMFS per year more than the 31 children (3.2 DMFS during 2 years) who had the lowest sugar intake (< 78 g/day).  相似文献   
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