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991.
Odontodysplasia is a relatively uncommon condition that can affect both primary and permanent dentition. It is characterized by defective formation of both enamel and dentin, with enlarged pulp chambers and root canals with open apices. It is usually a localised condition where one or few teeth may be involved. Sometimes, an entire quadrant or more than one quadrant may be involved but generalized involvement is extremely rare. An interesting case of a generalized odontodysplasia affecting both primary and permanent dentition in an eight year old girl is presented here.  相似文献   
992.
The goal of this investigation was to evaluate the effect of postoperative exposure of two different bioresorbable membranes on the guided tissue regeneration (GTR) healing results compared to nonexposed sites. In each of 25 patients one pair of contralateral intrabony lesions was treated either with polylactic acid (PLA) or polyglactin 910 (PG-910) membranes. Postoperative exposure occurred in 9 PLA and 13 PG-910 sites. Standardized clinical [papillary bleeding index (PBI), gingival recession (REC), probing pocket depth (PPD), probing attachment level (PAL)] and radiographic examinations (digital subtraction radiography) were performed immediately before (baseline) and 6 and 12 months postoperatively (p.o.). Subgingival bacterial samples from surgical sites were evaluated by culture at baseline, 6 weeks, and 6 and 12 months p.o. Six months after surgery the changes (Δ) of REC were significantly (P≤0.05) greater in exposed than in nonexposed sites, independently of the membrane material (median): exposed sites, ΔREC=–1 mm; nonexposed sites, ΔREC=0.0 mm. However, 12 months p.o. no significant differences were found due to a decrease in the initial recessions in exposed sites. Although a higher percentage of exposed than nonexposed sites harbored periodontal pathogens 6 weeks p.o. at the gingiva-faced membrane surface, membrane exposure did not have a significant negative effect on ΔPPD, ΔPAL, or radiographic bone density changes 6 and 12 months p.o. Both membranes showed significant gains in PAL and bone density in both exposed and nonexposed sites. In conclusion, this study demonstrates that with consistent infection control the postoperative exposure of PLA and PG-910 membranes has no significant negative effect on the regeneration outcome, although higher initial gingival recessions must be expected than in the nonexposed sites. However, in exposed sites plaque and infection control were clearly impeded by the rough, exposed membrane surfaces and by the initially negative gingival morphology. Received: 22 January 1997 / Accepted: 5 May 1997  相似文献   
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The results of reduction of tongue size in connection with orthodontic and surgical correction of prognathic anomalies of the jaws are presented. It is shown that reduction of the tongue size combined with orthodontic treatment arrests of tendency to prognathic growth when it is performed early. The results further indicate that the effect of prophylactic reduction of tongue size to check relapse following surgical correction of prognathism or open bite can only be confirmed in cases of genuine macroglossia. Since there was only one relapse in our cases without reduction of tongue size, the indication for preoperative prophylactic reduction of the tongue is limited. Personal results and experience have been compared with the findings published in the current literature.  相似文献   
1000.
Actinomyces viscosus 19246, T14V and T14AV, Streptococcus mutans and Streptococcus sanguis consumed complement in vitro. Complement (C) profile analysis revealed that C4 and C3–9 were consumed concomitantly in unadsorbed human serum. In serum from which naturally occurring agglutinating antibodies had been removed, the same microorganisms caused C3–9 consumption in the absence of a demonstrable loss of C4 activity. Congenitally C4-deficient guinea-pig serum (C4D) supported a similar consumption of C3–9. The Gram-positive plaque microorganisms tested activated serum complement by the classical as well as the alternate pathways. Dental plaque microorganisms may cause a similar activation of gingival crevicular fluid complement in vivo, thus resulting in complement-mediated inflammatory processes.  相似文献   
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