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991.
992.
Two patients with discolouration fo skin grafts after head and neck surgery, were treated with dermatography, a refined method of tattooing, and with intra-cicatricial keloidectomy, of which the results are described.  相似文献   
993.
994.
The advertising of dental services in South Africa is controlled by rules and regulations of the South African Medical and Dental Council. According to these, advertising is not permissible with the exception of specified professional information which may be made known only by means of a nameplate and an entry in a telephone directory. Questionnaires were sent to a randomised sample of 2,100 persons in order to determine the attitude of South Africans towards advertising by private practitioners. According to information obtained from this study there is a strong indication that consumers of dental services prefer a freer form of advertising by dentists in the private practice.  相似文献   
995.
Polypeptide growth factors are a class of potent natural biologic mediators which regulate many of the activities of wound healing including cell proliferation, migration, and metabolism. Platelet-derived growth factor (PDGF) and insulin-like growth factor-I (IGF-I) have been shown to regulate DNA and protein synthesis in bone cells in vitro and to interact synergistically to enhance soft tissue wound healing in vivo. We have hypothesized that the combination of PDGF and IGF-I may, therefore, enhance regeneration of both the soft and hard tissue components of the periodontium. To test this hypothesis we performed conventional periodontal surgery on all 4 quadrants of the mouth of 13 beagle dogs with naturally occurring periodontal disease. Following flap reflection, degranulation, and root planing, all premolar teeth in 2 quadrants of each dog received a combination of 3 micrograms of recombinant PDGF-B and IGF-I in a methylcellulose gel, while the premolar teeth in the contralateral quadrants received the gel alone. Teeth in 4 additional animals also received 125I-PDGF or 125I-IGF-I in the treated sites. The clearance rate of the 125I-labeled protein, changes in local bone metabolism, and amount of new bone and cementum with inserting collagen fibers were measured. The clearance studies revealed that the half-life of the factors at the site of application was 3.0 hours for IGF-I and to 4.2 hours for PDGF-B. Greater than 96% of the radio-labeled proteins was cleared by 96 hours and no radioactivity was detected 2 weeks after application. There was a significant (P less than 0.01) 2-fold increase in uptake of the bone-seeking radiopharmaceutical Technetium 99-MDP at 2 and 4 weeks in growth factor treated sites compared to controls, indicating that there was increased metabolic activity within the bone at these sites. Computer-aided histologic analyses of biopsies obtained at 2 and 5 weeks post-operatively revealed a significant (P less than 0.01), 5 to 10 fold increase in new bone and cementum in PDGF-B/IGF-I treated sites at both time points compared to controls receiving the placebo gel. The height and total area of new bone continued to increase from 2 to 5 weeks. The new bone underwent a normal maturation process as judged by histologic appearance. A physiologic periodontal ligament space was also formed between the new bone and new cementum. There was no increase in ankylosis in the treated sites.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
996.
The "universal jig" described in a previous article was tested on 10 patients to check for reliability. The recording of centric relation by this method was compared with Lucia's method of recording centric relation. The results of three series of three recordings were analyzed. The influence of the universal jig on rear-determinant movement was measured by two pantographic recordings, one enabling occlusion to take place, the other using the universal jig. The results were analyzed and demonstrated that the universal jig is a reliable means of simplifying the setting up of models and the programming of semiadjustable articulators.  相似文献   
997.
Nine clinical centers using the Br?nemark System participated in a prospective study of 159 partially edentulous patients between 18 and 70 years of age. Clinical parameters evaluated were plaque index, gingivitis, pocket depth, bleeding index, tooth mobility, and stomatognathic function. Initially, 558 fixtures were placed and 521 remained in the study following prosthesis placement (199 prostheses in 154 patients). Fixtures were lost or unaccounted for because of nonintegration prior to prosthesis fabrication (19), patient withdrawal (11), prosthodontic reasons (6), and failure during prosthetic procedures (1). Failure was primarily attributable to unfavorable bone quality, sex (more in males), and smaller fixture size. Complications and failure related to other patient characteristics are presented. After 1 year of a 5-year study, preliminary results suggest that a success rate equal to or better than that obtained with edentulous patients may be expected.  相似文献   
998.
999.
1000.
The fibroblast population in oral submucous fibrosis   总被引:2,自引:0,他引:2  
The purpose of the investigation was to compare the morphology of fibroblasts cultured from healthy oral mucosa and mucosa of patients with oral submucous fibrosis (OSF) and to collate the occurrence of cell types of similar morphology. Cells cultured from biopsy specimens from the buccal mucosa of six subjects who did not chew the areca nut and six patients with OSF who chewed areca nut were grown according to standard techniques. Ninety cells per cell line were recorded daily for 8 days, classified into types F1, F2 and F3 according to their morphology, and the results statistically analyzed. We found that there was a relative increase of F3 cells in relation to Fl cells in OSF resulting in the ratio of F3 to F1 cells being significantly larger in OSF than the ratio in the controls. As it has been reported that F3 cells m rat connective tissues produce significantly more collagen types I and III than F1 cells, we concluded that a change of fibroblast population has occurred in OSF and that this relative increase of F3 cells in humans, which could be committed to the production of large quantities of collagen, can be an explanation for the excessive collagen formation in OSF.  相似文献   
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