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991.
The standard treatment modality of zygomatic fractures is open reduction and rigid fixation of the fractured segments. Although most of the zygomatic fractures deserve this attentive surgical manipulation to prevent late residual asymmetry, minimally depressed noncomminuted zygomatic fractures can be reduced and fixed percutaneously. Percutaneous intervention causes minimal scarring and morbidity than open techniques and it is possible to align fragments precisely by using high-quality three-dimensional computed tomography (3-D CT) imaging. Six patients with noncomminuted fractures of the zygomaticomaxillary skeleton were evaluated with plain radiographs of facial bones, axial, coronal and 3-D CT. Reduction of the displaced bone segments were achieved by traction of percutaneously applied screw. Either reduced segments were not fixated at all or one of the two new fixation techniques, described in detail in the article, were used for stabilization of reduced segments. In all patients, accurate reduction was obtained. None of the patients showed any recurrent displacement or infection during the follow-up period of six months. The screws were removed in the clinical settings without difficulty. Although percutaneous reduction and external fixation of noncomminuted zygomatic fractures has limited indications, it has its own advantages over open techniques. This method is a less invasive technique and can be performed without any problem in selected cases. Our technique is not suitable for complex zygomatic and periorbital fractures.  相似文献   
992.
Recent studies have suggested that several systemic conditions--such as obesity, hypertension, hyperlipidemia, and diabetes--are related to periodontitis. The objective of this study was to examine the relationship between periodontitis and 5 components of metabolic syndrome--abdominal obesity, triglyceride level, high-density lipoprotein cholesterol level, blood pressure, and fasting blood sugar level--in 584 Japanese women. In multivariate analyses, persons exhibiting more components of metabolic syndrome had significantly higher odds ratios for a greater pocket depth and clinical attachment loss than did those with no components; the odds ratios for a greater pocket depth and clinical attachment loss of the persons exhibiting 4 or 5 components were 6.6 (95% confidence interval = 2.6-16.4) and 4.2 (95% confidence interval = 1.2-14.8), respectively. These results indicate that metabolic syndrome increases risk of periodontitis, and suggest that people exhibiting several components of metabolic syndrome should be encouraged to undergo a periodontal examination.  相似文献   
993.
AIM: To develop and evaluate an objective method for assessing lip size and treatment-related morphological changes in orofacial granulomatosis (OFG) patients. MATERIALS AND METHODS: Patients with swollen lips because of OFG (n=21) were enrolled. A light-body polyvinylsiloxane material was used to take lip impressions before and after treatment (n=10), or during treatment (n=11). Plaster models were cast from the impressions and the lips were measured using callipers. The intra-examiner and inter-examiner reproducibility of the technique were assessed. RESULTS: OFG patients had significantly larger lips than controls (P<0.0001). The coefficient of variation on repeated measurements of the same impression was 1.6% and for duplicate impressions was 2.6%. Significant reduction in lip size was shown in all 10 patients after diet restriction (P<0.002). Seven of 11 patients whose impressions were taken at least 3 months after the initiation of cinnamon- and benzoate-free diet also showed reduction in lip size during follow up (P<0.002). CONCLUSIONS: Serial lip impressions appear to be reliable for routine quantification of morphological changes of the lips in OFG patients. We present a new reproducible and sensitive method for assessing changes in lip size in response to treatment in OFG.  相似文献   
994.
995.
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   
996.
Ameloblastin (AMBN) cleavage products are the most abundant non-amelogenin proteins in the enamel matrix of developing teeth. AMBN N-terminal cleavage products accumulate in the sheath space between enamel rods, while AMBN C-terminal products localize within rods. We tested the hypothesis that MMP-20 is the protease that cleaves AMBN. Glycosylated recombinant porcine AMBN (rpAMBN) was expressed in human kidney 293F cells, and recombinant porcine enamelysin (rpMMP-20) was expressed in bacteria. The purified proteins were incubated together at an enzyme:substrate ratio of 1:100. N-terminal sequencing of AMBN digestion products determined that rpMMP-20 cleaved rpAMBN after Pro(2), Gln(130), Gln(139), Arg(170), and Ala(222). This shows that MMP-20 generates the 23-kDa AMBN starting at Tyr(223), as well as the 17-kDa (Val(1)-Arg(170)) and 15-kDa (Val(1)-Gln(130)) AMBN cleavage products that concentrate in the sheath space during the secretory stage. We conclude that MMP-20 processes ameloblastin in vitro and in vivo.  相似文献   
997.
A new method for lateral pterygoid electromyographic electrode placement   总被引:1,自引:0,他引:1  
STATEMENT OF PROBLEM: Making electromyographic recordings of the lateral pterygoid muscle (LP) is difficult because of potential electrode damage to, for example, the maxillary artery and long buccal nerve, and because of pain and reduced jaw mobility characteristic of many orofacial pain patients. PURPOSE: The purpose of this study was to develop a reliable intraoral placement technique for the inferior head of the lateral pterygoid (IHLP) that minimizes jaw displacement. MATERIAL AND METHODS: In 2 dried skulls and 7 human cadavers, it was estimated that, with the mandible in an ipsilateral closed position, a straight needle could be used to position fine-wire electrodes into the midportion of IHLP by inserting the needle through the mucosa adjacent to the distal root of the maxillary second molar, towards the external auditory meatus and parallel to the buccal alveolar bone of the maxilla. The needle avoided the maxillary artery and long buccal nerve. Using this approach in 5 adults, 2 fine-wire electrodes were placed into the IHLP. Placement was verified by computer tomography (CT) and electromyography. RESULTS: In all subjects, the ideal insertion depth to place the electrodes in the middle of IHLP was 29 mm. CONCLUSIONS: This technique is a reliable method for IHLP electrode placement for patients with impaired jaw function, minimizing risk of damage to major structures.  相似文献   
998.
AIM: Oral and dental health improved tremendously over the last fifty years in Italy but still prevalence of dental caries in children remains a significant clinical problem. This report describes the National Italian Guidelines for caries prevention. METHODOLOGY: A panel of experts coordinated by the Italian Society of Paediatric Dentistry (SIOI) planned to elaborate the national Italian guidelines for caries prevention in children. The structure of the guidelines has been planned to follow the principles of modern caries treatment and management as well as science based dentistry. The main procedure was based on a hierarchic evaluation of literature. CONCLUSION: The guidelines are planned for dentist working in primary dental care, however, they are also designed to be of interest for other care professionals such as paediatricians, gynecologists, pharmacists and general medical practitioners and also for parents and/or guardians of the children.  相似文献   
999.
Asymptomatic third molars may have associated periodontal pathology that may not be limited to the third molar region and have a negative impact on systemic health. Third molars should be considered for removal when there is clinical, radiographic, or laboratory evidence of acute or chronic periodontitis, caries, pericoronitis, deleterious effects on second molars, or pathology. Radiographic findings of extreme locations of impacted teeth, dense bone, dilacerated roots, large radiolucent lesions associated with impactions, and lower third molar apices in cortical inferior border bone are predictive of more complex surgery. Certain demographic and oral health conditions available to the surgeon before surgery and intraoperative circumstances are predictive of delayed recovery for health-related quality of outcomes and delayed clinical outcomes after third molar surgery.  相似文献   
1000.
Self-etching primers/adhesives that combine acidic methacrylate monomers with water in a single bottle are hydrolytically unstable and require refrigeration to extend their shelf-lives. This study tested the null hypothesis that one year of intermittent refrigeration of a 4-MET-containing simplified self-etching primer does not result in hydrolytic changes that are identifiable by transmission electron microscopy and (13)C NMR spectroscopy. Human dentin was bonded with UniFil Bond immediately after being unpacked, or after one year of intermittent refrigeration at 4 degrees C. Fresh and aged primers were analyzed by NMR for chemical changes. Ultrastructural observations indicated that there was an augmentation in etching capacity of the aged adhesive that was not accompanied by resin infiltration or effective polymerization. New NMR peaks detected from the aged ethanol-based primer confirmed that degradation occurred initially via esterification with ethanol, followed by hydrolysis of both ester groups in the 4-MET. Hydrolysis of functional methacrylate monomers occurs despite intermittent refrigeration.  相似文献   
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