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Dentine sialoprotein (DSP) represents 5-8% of all non-collagenous proteins present in the tooth, but, together with dentine phosphoprotein, has been shown to be vital for correct tooth formation. Recently, the existence of a highly glycosylated form of porcine DSP has been reported and it was shown to possess glycosaminoglycan (GAG) chains. The current investigation confirms that this is also the case for bovine DSP and has further characterized these carbohydrates. Dentine sialoprotein was purified from bovine dentine extracts by anion exchange chromatography and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), western blotting, and mass spectroscopy. An increase in molecular mass was observed, from 120 kDa to greater than 250 kDa, with a corresponding rise in anionic strength. Cellulose acetate electrophoresis and western blotting indicated the presence of chondroitin sulfate GAG chains within these dentine fractions. Further examination using sequential digestion with chondroitinase AC and N-glycosidase cleaved the samples first to 95 kDa and then to 80 kDa, respectively, confirming a high level of glycosylation. These results support the classification of bovine DSP as a proteoglycan, and that the carbohydrate substitutions may contribute to the functional properties of DSP.  相似文献   
23.
BACKGROUND: Inflammatory and anti-inflammatory mediators may play a significant role in patients with gingivitis. The purpose of this study was to assess the short-term effects of the systemic administration of two different concentrations of aspirin (81 and 325 mg/day, by mouth) on clinical periodontal parameters and gingival crevicular fluid (GCF) levels of 15-epi-lipoxin A4 (15-epi-LXA4), lipoxin A4, leukotriene B4 (LTB4), prostaglandin E2 (PGE2), and interleukin (IL)-6 and -1beta in a sample of naturally occurring gingivitis patients. METHODS: At day 0, after initial screening for entry, baseline periodontal parameters, including bleeding on probing (BOP), periodontal probing depths (PDs), and plaque index (PI) were measured, and GCF was sampled from 12 intrasulcular sites with filter paper strips for the measurement of six types of inflammatory and anti-inflammatory mediators using competitive enzyme immunoassay and enzyme-linked immunosorbent assay (prevalues). Forty-seven subjects were assigned randomly to one of three treatment groups: placebo (15 subjects); aspirin, 81 mg (16 subjects); and aspirin, 325 mg (16 subjects) once daily. On day 7, subjects were recalled for the measurement of periodontal parameters and collection of GCF samples for the measurement of six types of mediators (postvalues). RESULTS: Changes in inflammatory and anti-inflammatory mediator levels were not statistically significant for any of the three treatment groups. However, when pre- and postvalues were compared in the subjects receiving aspirin, 325 mg, there was a negative trend in the relationship between 15-epi-LXA4 and PGE2, whereas the relationship between LTB4 and PGE2 was not as strong. This might indicate that the subjects responding to aspirin-mediated PGE2 suppression effects produced higher 15-epi-LXA4 in GCF than non-responders. No statistically significant differences in PD and PI between pre- and postvalues were found for any of the three treatment groups. However, the results demonstrated a significant increase in BOP when aspirin, 325 mg was compared to placebo (P <0.001) and aspirin, 81 mg (P = 0.001). CONCLUSIONS: Aspirin can have an affect on BOP in naturally occurring gingivitis patients. Although most of the inflammatory mediators did not show significantly detectable changes after aspirin treatment for 7 days, the trend of aspirin-associated increases of 15-epi-LXA4 implied that this recently discovered aspirin-dependent eicosanoid may be associated with the increased incidence of BOP observed in the subjects who received aspirin therapy.  相似文献   
24.
There is no commonly accepted standardized terminology for oral diagnoses. The purpose of this article is to report the development of a standardized dental diagnostic terminology by a work group of dental faculty members. The work group developed guiding principles for decision making and adhered to principles of terminology development. The members used an iterative process to develop a terminology incorporating concepts represented in the Toronto/University of California, San Francisco/Creighton University and International Classification of Diseases (ICD)-9/10 codes and periodontal and endodontic diagnoses. Domain experts were consulted to develop a final list of diagnostic terms. A structure was developed, consisting of thirteen categories, seventy-eight subcategories, and 1,158 diagnostic terms, hierarchically organized and mappable to other terminologies and ontologies. Use of this standardized diagnostic terminology will reinforce the diagnosis-treatment link and will facilitate clinical research, quality assurance, and patient communication. Future work will focus on implementation and approaches to enhance the validity and reliability of diagnostic term utilization.  相似文献   
25.
Piercing has become so popular during the last 20 to 30 years that many physicians are now treating patients with piercings and dealing with its side effects. We present 3 cases that illustrate the complications of tongue piercing (ie, infection, bleeding, and embedded ornaments). We describe the methods for inserting the ornaments to illustrate the possible adverse effects. Treatment recommendations and their application to those 3 patients are described.  相似文献   
26.
One patient with a solitary plasmacytoma of the frontal bone was treated with complete surgical resection. To reconstruct the large calvarial defect, a split-thickness calvarial graft was harvested from the parietal area and secured in place with miniplates. Solitary plasmacytomas of the calvaria are not common. Clinical presentation, diagnostic criteria, therapeutic approaches, and prognosis are discussed.  相似文献   
27.
A technique for the restoration of carious primary maxillary incisors using indirect resin composite crowns and intracanal reinforcement fiber is described. Endodontic treatment was previously performed on each tooth. The advantages of using an intracanal reinforcement fiber include resin composite crown reinforcement, translucency, and relative manipulation facility. In addition, the use of indirect resin composite crowns provides good shape and esthetics, as well as reduced chair time for the child. The technique is illustrated in a case report in which indirect resin composite crowns and an intracanal reinforcement fiber are placed in a 3-year-old girl.  相似文献   
28.
BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been shown to induce clinically relevant bone formation for orthopedic, craniofacial, and oral indications. It appears critical, in particular for onlay indications, that the associated carrier technology exhibits structural integrity to offset compressive forces in support of rhBMP-2-induced bone formation. The objective of this study was to evaluate a calcium phosphate (CP) cement, Ceredex, as a candidate carrier for rhBMP-2 in a defect model with limited osteogenic potential. MATERIALS: Bilateral, critical size, 6-mm, supra-alveolar, periodontal defects were created in six, adult, male, Hound Labrador mongrels. Three animals received rhBMP-2/Ceredex (rhBMP-2 at 0.20 and 0.40 mg/ml) in contralateral defect sites (implant volume/defect approximately 1 ml). One defect site in each of the three remaining animals received Ceredex without rhBMP-2 (control). The animals were euthanized at 12 weeks postsurgery for histologic and histometric analysis. RESULTS: Mean induced bone height exceeded 80% of the defect height for supra-alveolar periodontal defects receiving rhBMP-2/Ceredex without major differences between rhBMP-2 concentrations compared with approximately 40% for the control. The newly formed bone, a mixture of lamellar and woven bone in fibrovascular tissue, circumscribed relatively large portions of the residual Ceredex biomaterial. Inflammatory lesions were associated with limited bone formation in some sites. From a periodontal perspective, sites receiving rhBMP-2/Ceredex exhibited increased cementum formation compared with control, but without a functionally oriented periodontal ligament, and increased ankylosis and root resorption. Control sites exhibited early wound failure and exposure, loss of the Ceredex biomaterial, and limited bone formation. CONCLUSIONS: The Ceredex CP cement appears a potentially promising carrier technology for rhBMP-2 onlay indications. However, a slow resorption rate may prevent its wider use. This study does not support use of the rhBMP-2/Ceredex combination for periodontal indications.  相似文献   
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This study aimed to identify all Staphylococcus aureus (MRSA) cases on a Regional Maxillofacial ward, to estimate incidence and to ascertain who were most at risk. The study also explored clinical and demographic factors associated with MRSA in a subset of consecutive patients managed by primary surgery for previously untreated oral and oropharyngeal squamous cell carcinoma (OOSCC) over the same time period. Patients admitted from 1st April 2001 to 31st March 2006 to the Regional Maxillofacial Unit ward, Liverpool were identified by a retrospective review of the hospital MRSA database and there were 10109 patient admissions. MRSA (1.1%) occurred in 115 patient episodes involving 97 patients. There were 84 patients having a single episode and 13 more than one. There were no cases of mortality due to MRSA. Of the MFU patients 73 were oncology and 7 trauma. In the oncology group the commonest primary sites were wound (41) and sputum (11). Of new patients admitted for definitive treatment for OOSCC, 14% had MRSA and the two main risk factors were stage of cancer (P<0.001) and free flap (P<0.001). The risk of MRSA infection on our maxillofacial ward is low though MRSA infection is more prevalent among oncology patients particularly those requiring free tissue transfer. Careful adherence to infection prevention and control precautions is essential and practical methods to reduce MRSA need further evaluation.  相似文献   
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