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991.
Mahmood S MacLeod SP Lello GE 《The British journal of oral & maxillofacial surgery》2002,40(4):300-303
The British Association of Oral and Maxillofacial Surgeons (BAOMS) and the Royal College of Surgeons of Edinburgh (RCSEd) have had leading roles in organisation, assessment and improvement of surgical training in the United Kingdom. This was particularly well illustrated by the establishment of the fellowship examination in Oral and Maxillofacial Surgery (FRCSEd, OMFS). 相似文献
992.
993.
The evolution of the esthetic movement has been sustained over time because it touches a base psychological need for most people to feel they are attractive, youthful, and a vital part of society. Through well-organized team diagnosis and treatment planning, patients can benefit from a solid diagnostic and prerestorative foundation that can more predictably produce consistent optimal treatment results. As the chief diagnostician and treatment supervisor, the restorative dentist must continue to advance his or her knowledge and training to provide the other team members with a concise treatment vision for the patient. With a newly developed synergy among the disciplines of dentistry for team treatment and tremendous advancement in dental markets and equipment, it is possible to create natural-looking, esthetic rehabilitative treatments. 相似文献
994.
Keith H. Sherwood DDSa James G. Burch DDS MSb William J. Thompson DDS MSb 《American journal of orthodontics and dentofacial orthopedics》2002,122(6):593-600
The intent of this study was threefold: (1) to validate true intrusion of molars in adults, (2) to test the stability of miniplates as anchorage for intruding posterior teeth in the maxilla, and (3) to record the skeletal and dental changes of open-bite closure. Four adult patients who had anterior open-bite malocclusions were selected to undergo posterior intrusion with miniplate anchorage to close the open bite; all had true intrusion of the maxillary molars. Mean molar intrusion was 1.99 mm (range, 1.45-3.32 mm). No movement of miniplates occurred at any time during their use or before intentional clinical removal. Open-bite closure was achieved for all 4 patients. Mean closure of incisors was 3.62 mm (range, 3.0-4.5 mm) as the mandibular plane closed 2.62 degrees (range, 1.5 degrees -4.5 degrees ), and the occlusal plane decreased 2.25 degrees (range, 1.0 degrees -3.5 degrees ). Anterior facial heights decreased as the mandible closed and B-point rotated anteriorly and upward. 相似文献
995.
Evaluation of bone height and bone density by computed tomography and panoramic radiography for implant recipient sites 总被引:2,自引:0,他引:2
The objective was to compare the bone height and bone density measurements of implant recipient sites by panoramic radiography and computed tomography. Thirty-seven sites of 21 patients were evaluated using both panoramic radiography and computed tomography. The bone height was measured as the vertical distance from the alveolar crest to the closest anatomical landmark. Density was compared by means of densitometric measurements. Data was evaluated using paired t-test and Pearson's correlation coefficient analysis. Although bone heights measured with the two imaging modalities differed significantly (p < 0.05), there was a significant correlation between bone density measurements (r = 0.93, p = 0.0). Measurements of bone height as well as bone density was found to be comparable using either radiographic method. 相似文献
996.
Contribution of individual drugs to gingival overgrowth in adult and juvenile renal transplant patients treated with multiple therapy 总被引:2,自引:0,他引:2
R. F. Wilson A. Morel D. Smith C. G. Koffman C. S. Ogg S. P. A. Rigden F. P. Ashley 《Journal of clinical periodontology》1998,25(6):457-464
Abstract. Drug regimens for transplantation often consist of multiple therapeutic agents and may result in drug-induced gingival overgrowth (DIGO). The aim of this study was to investigate the contribution of individual drugs in renal transplant patients. 147 adults (19–84 years) and 60 juveniles (3–18 years) were scored for DIGO and other clinical variables. Duration of treatment, dosage of drugs per kg body weight and serum cyclosporin levels were recorded. 44% of adults and 27% of children had DIGO. All patients were receiving prednisolone. More adults than children were administered cyclosporin, the reverse was true of azathioprine ( P 0.01), Explanatory models were evaluated by stepwise ordinal polynomial logistic regression. Statistically significant explanation ( P 0.05) of DIGO was afforded by prednisolone, nifedipine and azathioprine concentrations in adults and by cyclosporin, nifedipine and azathioprine concentrations in juveniles. Prednisolone and azathioprine were inversely related to the degree of DIGO. Plaque and irregularity scores, lip coverage and mouthbreathing status showed significant additional explanation in adults, replacing nifedipine and azathioprine in the final model. Irregularity was additionally explanatory in children, but no other clinical variables. A larger proportion of the variance of DIGO was explained by the available variables in children than in adults (pseudo r 2 =0.50 versus 0.25). The degree of DIGO in renal transplant patients is influenced by the dosage of a number of individual components of multiple drug therapy independently of the presence of local clinical factors. 相似文献
997.
The complex, pennate architecture of the human masseter muscle points to a functional division into more than the commonly distinguished deep and superficial parts. In this study, the possible existence of regional differences in activation was examined. EMG activity was registered in three deep and three superficial regions with the use of bipolar fine-wire electrodes. Recordings were made during different static bite tasks, in specified directions, and with a specified bite-force magnitude. A linear bite-force/EMG relationship was observed. Furthermore, it appeared that muscle regions showed a different pattern of change in activity as a function of bite-force direction. Heterogeneity was nearly absent in anteriorly-, anteriomedially-, and medially-directed bites, but became increasingly obvious in the other bite-force directions. The posterior deep region showed the most aberrant activation pattern, which was almost opposite that from the other regions. This part was fully active in posterolaterally-directed bites. The posterior superficial region showed the largest variability in activity as a function of bite-force direction. The results point to a functional partition of the masseter muscle in at least three parts: anterior deep, posterior deep, and superficial. A further subdivision of the superficial portion might be present, but was not as obvious as the division of the deep masseter. 相似文献
998.
Dentine phosphoprotein (DPP), a major non-collagenous acidic protein of dentine, undergoes altered phosphorylation in vivo in the presence of high fluoride concentrations. This has major implications for the altered mineralization patterns found during fluorosis. In dentine, casein kinase II is involved in phosphorylating DPP, and alkaline phosphatase (ALP) is ascribed roles in the dephosphorylation of DPP, increasing the inorganic phosphate at the mineralization front and the removal of pyrophosphate. Here the influence of fluoride in vitro on the activity of purified casein kinase II and ALP and its relation to altered patterns of mineralization were examined. Kinetic analysis showed that casein kinase II activity was completely inhibited at 0.04 M NaF. Vmax when compared to the control assay was significantly decreased (P < 0.0001) between concentrations 4 x 10(-4)-4 x 10(-8) M NaF. Significant changes to the Km (P < 0.0001) were also observed. ALP activity was inhibited by NaF (0.09-9 x 10(-8) M), with Vmax significantly decreased (P < 0.0001) at 0.09 M NaF. Alterations in the activity of these enzymes in the presence of fluoride may in part explain the decreased phosphorylation observed in DPP isolated from fluorotic dentine and may aid understanding of the altered matrix mediated mineralization patterns found during fluorosis. 相似文献
999.
Information regarding the presence of the free radical scavenging (inactivating, dismutating) enzyme superoxide dismutase in human dental pulp was sought. Free radicals, such as the superoxide anion radical (O2-) and the hydroxyl anion radical (OH.), are powerful biological oxidants produced by phagocytes during the normal tissue response to injury and infection. Also produced is hydrogen peroxide (H2O2), an aggressive oxygen species formed by the reaction of superoxide with itself, i.e., a dismutation in which one molecule of O2- is oxidized by the other. These three reactive oxygen intermediates serve as part of the normal host biological defense mechanism for the inactivation of microorganisms and the breakdown of their toxic products. Both normal and inflamed dental pulps were assayed for the presence of this enzyme. Superoxide dismutase activity was identified in the normal pulpal tissues. There was a slight decrease in activity with age. In the inflamed pulpal tissues, enzyme activity was markedly and significantly increased in comparison to that in the normal tissues. These observations indicate that human dental pulp possesses an endogenous defense mechanism designed to protect the tissue components (cells and matrix) from the toxic effects of the reactive oxygen intermediates. In this regard, the inflammatory response of this specialized and somewhat isolated (compartmentalized) tissue is not unlike that seen in other connective tissues. 相似文献
1000.
Attitudes to glove wearing by dentists practising within the NHS Regulations were tested by means of a questionnaire distributed to 2000 dentists in England and Wales. The response was 76.5%. The results indicate that 68% of the respondents wore gloves routinely for all patients and procedures, 3% never wore gloves, while the remainder (29%) wore gloves for only selected patients or selected procedures. Reasons given for not wearing gloves routinely included problems of comfort, loss of tactile sensation and the risk of cross-infection, which was perceived to be small. Of the routine glove wearers, only 12% changed gloves between patients, cost being considered to be a factor by 57% of respondents who used gloves for more than one patient. The results indicate that the respondents practising and personal details had an influence on the pattern of glove wearing, with single-handed practitioners and those who graduated before 1979 being less likely to wear gloves routinely. Comparison with the findings of earlier studies of similar type suggest that there is increased awareness in the dental profession of the necessity for glove wearing, but that there is still a need to encourage routine glove use, especially amongst certain groups of GDPs. 相似文献