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21.
A prototype imaging system for intraoral dental xeroradiography has been described. In vivo evaluations of image quality show that intraoral xeroradiographs are superior to conventional intraoral film radiographs primarily because of the wide latitude and edge enhancement properties of xeroradiography. In addition, intraoral xeroradiography requires only a third of the radiation dose of corresponding intraoral film techniques.  相似文献   
22.
A new dental xeroradiographic processor was clinically tested. In comparison with conventional radiographs, xeroradiographs often showed more anatomic detail of teeth and bone and required approximately half the exposure time. These characteristics, the speed of operation and the added features for convenience, suggest that xeroradiography may be important to dental radiography in the future.  相似文献   
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The purpose of this study was to determine whether erroneous kVp meter readings, induced by plastic wrap, affected the actual kVp (output) of a dental X-ray machine. To evaluate the effect of plastic wrap on dental X-ray machine kVp meters, a radiation output device was used to measure output in mR/ma.s. An intraoral dental X-ray unit (S.S. White Model #90W) was used to make the exposures. First, the kVp meter was not covered with plastic wrap and output readings were recorded at various kVp settings with the milliamperage and time held constant. Secondly, the same kVp settings were selected before the plastic wrap was placed. Milliamperage and time were again held to the same constant. The X-ray console was then covered with plastic wrap prior to measuring the output for each kVp. The wrap possessed a static charge. This charge induced erroneous kVp meter readings. Out-put readings at the various induced kVp settings were then recorded. A kVp of 50 with no wrap present resulted in the same output as a kVp of 50 induced to read 40 or 60 kVp by the presence of wrap. Similar results were obtained at other kVp settings. This indicates that the plastic wrap influences only the kVp meter needle and not the actual kilovoltage of the X-ray machine. Dental X-ray machine operators should select kVp meter readings prior to placing plastic wrap and should not adjust initial settings if the meter is deflected later by the presence of wrap. The use of such a procedure will result in proper exposures, fewer retakes, and less patient radiation. If plastic wrap leads to consistent exposure errors, clinicians may wish to use a 0.5% sodium hypochlorite disinfectant as an alternative to the barrier technique.  相似文献   
25.
Staying alive     
  相似文献   
26.
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   
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28.
The history, mechanism and aetiology of Horner'sy Syndrome is presented and the pharmacology of the pupil is discussed. The case reported is a rare combination of Horner's Syndrome in a patient who sustained bilateral fractures of the mandible and a chest injury. It is emphasised that the miotic changes in Horner's Syndrome, in combination with head injuries can lead to confusion in diagnosis and the potential anaesthetic hazards and their influence on the management of the facial injury are outlined.  相似文献   
29.
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   
30.
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