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981.
Background: Therapeutic decisions in periodontal surgery are based on the accurate diagnosis of the furcation. Clinical probing is the basic diagnostic tool; however, the accuracy of clinical probing to distinguish Class II and Class III furcation defects is unknown. Therefore, this study compares clinical probing diagnoses to those of computed tomography (CT). Methods: Seventy‐five patients with severe periodontal disease were enrolled in this case series study. A total of 582 furcation sites in molars were assigned for the diagnosis of Class II and Class III furcation defects by clinical probing. Diagnosis based on CT served as a reference. Results: The degree of furcation involvement on clinical findings was confirmed in 57% of the sites, whereas 20% were overestimated and 23% were underestimated compared with the radiologic analysis. Only 32% of Class III furcations in the CT scan were detected clinically. The best correlation of CT scan and clinical probing was found at buccal furcation sites in the mandible, with a κ‐coefficient of 0.52, and buccal furcation sites in the maxilla, κ = 0.38. The κ‐coefficient was 0.35 for lingual furcations, 0.29 for mesial furcations, and 0.27 for distal furcations, showing weaker correlations. Conclusions: CT scans offer more detailed information on furcation involvement than clinical probing. Especially before surgical treatment, three‐dimensional radiographic imaging can be a useful tool to assess the degree of furcation involvement and optimize treatment decisions.  相似文献   
982.
983.
Gingivoperiosteoplasty (GPP) has produced inconsistent outcomes. The purpose of this prospective study was to investigate the effects of GPP on the production of bone and maxillary growth. We analysed postoperative cone-beam computed tomographic (CT) scans and intraoral dental photographs of 25 children with complete unilateral cleft lip and palate (UCLP) who were treated with GPP at the same time as their primary repair of the lip. Residual cleft defects and unsupported root ratios of central incisors adjacent to clefts were measured from scans. Dental arch relations were assessed from photographs using the Goslon (Great Ormond Street London and Oslo) yardstick. Eighteen children did not require secondary alveolar bone grafts. Residual cleft defects varied by site (20.4 mm3, 38.6 mm3, 88.2 mm3, and 135.2 mm3 for buccal coronal, palatal coronal, buccal apical, and palatal apical defects, respectively; p < 0.001). Unsupported root ratios did not differ significantly between coronal and apical central incisors adjacent to clefts. The mean (SD) Goslon score was 4.52 (0.51). Most participants (n = 18) who had a GPP did not need secondary alveolar bone grafting. GPP resulted in least bone on the palatal apical portion of the previous alveolar cleft and relatively good periodontal bony support of central incisors adjacent to the cleft. We no longer use GPP because of our concerns about maxillary growth.  相似文献   
984.
985.
986.
PurposeThe purpose of this study was to investigate computed tomography (CT) and clinical features relating to calcifications within the parotid gland of patients with Sjögren's syndrome (SS).MethodsData from 30 patients with SS who had been examined by CT were extracted from our radiological information database accumulated from 2001 to 2011, and their CT images were reread carefully. Of these patients, 14 (all female; age range 20–95 years; mean age 61.4 years) with calcifications within the parotid gland were retrospectively investigated with CT findings. The relationship between calcification occurrence and clinical symptoms including parotid swelling and/or saliva colic was investigated. The degree of destruction of the parotid gland on CT images was also evaluated.ResultsAll calcifications of 14 patients were located within the parotid gland, not in the parotid duct. CT images of all calcifications showed small and regular round shapes. Multiple occurrences of calcifications were recognized in 10 patients, and a solitary occurrence was seen in 4 patients. Seven patients had bilateral calcifications. There was little relationship between the occurrence of calcifications and clinical symptoms, and the severity of destruction of the parotid gland.ConclusionThe presented CT and clinical features would be peculiar to SS because too many patients lacked the typical features of sialoliths within the parotid gland.  相似文献   
987.
Abstract

Objective: Cone beam computed tomography (CBCT) is a specialized form of radiography and has been used in the Glasgow Dental Hospital since 2006. The clinical notes of all patients referred for CBCT from the orthodontic department between 2006 and 2011 were evaluated to determine the reasons for referral, scan parameters and clinical findings.

Design: Retrospective observational study.

Materials and methods: From a general database, the notes of patients from the Orthodontic Department of Glasgow Dental Hospital & School referred for CBCT imaging, since the inception of the service (2006 through to 2011) were examined. Information was obtained from CBCT request forms, case notes and radiology reports.

Results: During the chosen time period, 290 patients were referred for CBCT. Of these, 280 had clinical records that were available for investigation. Analysis showed approximately a third of scans were carried out within 4 weeks of referral. The smallest height of 4 cm was used for over a third of the scans investigated. Sixty-two per cent of the scans examined the maxilla only, 32% both jaws and 6% the mandible only. The two most common reasons for referral were to accurately determine the position of impacted teeth and to identify the presence of root resorption in relation to impacted teeth. In this cohort, 39% of teeth adjacent to an impacted tooth were found to have some root resorption, which closely supports the current literature.

Conclusions: This study provides a general overview of CBCT used by an orthodontic department in a teaching hospital environment.  相似文献   
988.
Although several reports have revealed that fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG PET) is useful for differentiating between benign and malignant lesions in the gallbladder, the positive results of 18F-FDG PET are not specific for malignancy because 18F-FDG is also accumulated in inflammatory lesions. It is known that the most important pathway for 18F-FDG to enter the cell body is mediated by the facilitative glucose transporter-1 (GLUT-1) through GLUT-3. We herein present a case of xanthogranulomatous cholecystitis (XGC) with a positive result on 18F-FDG PET. In this case, GLUT-1 and GLUT-3 were both positively expressed in inflammatory cells at the gallbladder wall of XGC and this is the first report to reveal GLUT expression in XGC. This report reveals that surgeons should carefully consider the appropriate treatment of gallbladder tumor, even with a positive result on 18F-FDG PET.  相似文献   
989.
990.
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