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1.
PURPOSE: The introduction of microsurgical instruments and magnification devices has brought advantages in root-end management and the application of root-end filling materials. The main purpose of this prospective clinical study was to monitor the outcome of ultrasonic root-end preparation using magnification loupes or an endoscope. Tooth location and the presence of post restoration were also examined as potentially affecting the outcome. MATERIALS AND METHODS: Teeth treated surgically showed a periradicular lesion of strictly endodontic origin. A total of 59 patients were included in the study, according to specific selection criteria. Following the reflection of a full mucoperiosteal tissue flap, residual soft tissues were curetted, root ends were resected, and root-end cavities were prepared ultrasonically with a zirconium nitrate tip, and zinc oxide EBA-reinforced cement root-end fillings were placed. Thirty-two root-end management procedures were performed using magnification loupes and 39 using an endoscope. All cases followed for a period of 1 year were classified into 3 groups (success, uncertain healing, and failure) according to radiographic and clinical criteria. RESULTS: Of the 71 teeth evaluated at 1-year follow-up, 67 teeth (92.95%) successfully healed, 3 teeth had uncertain healing, and 2 failed. In the group using endoscopy, 94.9% of successful healing was achieved, while for the other group, 90.6% was recorded. We found no statistically significant differences in treatment results related to the arch (P = .20), post restoration (P = .21), or type of magnification device (P = .08). CONCLUSIONS: In the present study, adherence to a strict endodontic surgical protocol and the use of modern surgical endodontic procedures, together with visual magnifications, resulted in an overall high success rate.  相似文献   
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Several neurophysiological studies have highlighted the role of the midbrain periaqueductal gray matter (PAG) in the initiation of vocalization in various animal species, from frogs to primates. With regard to humans, only two cases of complete mutism following a lesion to the PAG have been reported so far. This article describes a new case of a patient (GM) who, following an ischemic lesion to the periaqueductal gray region of the midbrain, presented with complete and irreversible mutism, though her language comprehension functions and her non-verbal expression capacity were preserved. This clinical case provides evidence that in humans the PAG also acts as a link between different vocalization-eliciting external and internal stimuli (which reach the PAG from sensory and emotional structures) and the vocal-motor coordinating mechanisms in the lower brain stem.  相似文献   
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Mental imagery is part of people''s own internal processing and plays an important role in everyday life, cognition and pathology. The neural network supporting mental imagery is bottom‐up modulated by the imagery content. Here, we examined the complex associations of gender and age with the neural mechanisms underlying emotion imagery. We assessed the brain circuits involved in emotion mental imagery (vs. action imagery), controlled by a letter detection task on the same stimuli, chosen to ensure attention to the stimuli and to discourage imagery, in 91 men and women aged 14–65 years using fMRI. In women, compared with men, emotion imagery significantly increased activation within the right putamen, which is involved in emotional processing. Increasing age, significantly decreased mental imagery‐related activation in the left insula and cingulate cortex, areas involved in awareness of ones'' internal states, and it significantly decreased emotion verbs‐related activation in the left putamen, which is part of the limbic system. This finding suggests a top‐down mechanism by which gender and age, in interaction with bottom‐up effect of type of stimulus, or directly, can modulate the brain mechanisms underlying mental imagery.  相似文献   
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Background. The maxillary sinus lift is a popular and predictable technique associated with implant-supported rehabilitation of the severely atrophic maxilla. The aim of the present retrospective study was to investigate the effectiveness of transcrestal maxillary sinus augmentation and the graft resorption pattern using different heterologous bone substitutes. Methods. A total of 75 sinus-grafting procedures were performed and 89 implants were placed in 66 patients, 24 males and 42 females, with mean age 67.9 ± 10.64 years (range 43–84 years). Nineteen subjects were smokers. The mean follow-up period was 93.33 ± 54.71 months (range 14–240 months). Clinical and radiographical evaluations were performed. Graft height and width were measured at baseline and at the latest follow-up. Results. Mesiodistal and vertical resorption averaged 9.3 ± 20.7% (standard deviation), and 5.04 ± 9.9% of the postoperative size, respectively, considering the graft as the unit. Linear regression analysis showed that graft resorption in both the vertical and the mesiodistal dimension is independent of the follow-up time. Conversely, there was a trend for greater resorption when increasing the postoperative graft size, in both vertical (p = 0.001) and horizontal (p = 0.007) dimensions. When grouping the dimensional changes by graft particle size (only small (<300 μm) particles, combination of small and medium (>500 μm)/large (>1000 μm) particles, and only medium/large particles), there was a trend for greater resorption associated with smaller particles, but it was not significant; neither in the mesiodistal nor in the vertical dimension (p = 0.17 and p = 0.25, respectively). No implant was lost during the observation period. In conclusion, the transcrestal technique for maxillary sinus augmentation documented a high level of predictability. The low clinical morbidity and the contextual dental implant positioning is clinically useful in relation to a significant reduction of the time required for implant restoration, a consistent decrease of the number of surgical phases, and a cost-effectiveness approach for the rehabilitation. The graft resorption pattern in all cases was compatible with persistent implant protection and support.  相似文献   
7.
BACKGROUND: A surgical approach based on ultrasound-guided hepatectomy might minimize the need for major resection, whose rates of morbidity and mortality are not negligible. Right hepatectomy (RH) is traditionally performed in cases of vascular invasion of the right hepatic vein with multiple tumors in the right posterior section, and/or of the right posterior portal branch (P6-7) with tumor in contact with right anterior portal branch (P5-8). We herein describe an alternative approach to RH consisting in ultrasound-guided systematic extended right posterior hepatic sectionectomy (SERPS). METHODS: Among 207 consecutive patients who underwent hepatectomies, 21 (10%) underwent SERPS. Median age was 67 years (range, 48-79). There were 13 men and 8 women. Ten (48%) patients had hepatocellular carcinoma; 11 (52%) had colorectal liver metastases. Median tumor number was 2 (range, 1-15); median tumor size was 4.5 cm (range, 2.5-20). Ten (48%) patients had cirrhosis, 8 (38%) had steatosis, and 3 (16%) had normal liver. Surgical strategy was based on tumor-vessels relationship at intraoperative ultrasonography (IOUS) and on findings at color-Doppler IOUS. RESULTS: In-hospital and 90-days mortality were nil. Major and minor morbidity occurred in 3 (14%) and 2 (9.5%) patients, respectively. No patients were reoperated because of complications. Blood transfusions were given to 2 (9.5%) patients. After a median follow-up of 21 months, no local recurrence was observed. CONCLUSIONS: IOUS-guided SERPS is feasible, safe, and effective. It should be applied whenever possible as alternative resection to RH to maximize liver parenchymal sparing.  相似文献   
8.
BACKGROUND: Despite higher blood loss, morbidity, and mortality, rate of major resection is still high in most surgical institutions because of fear of incomplete tumor removal. To verify whether intraoperative ultrasonography (IOUS) minimizes the rate of major hepatectomies while maintaining treatment radicality, we have prospectively validated our policy, based on extensive use of IOUS resection guidance. STUDY DESIGN: Ninety-three consecutive patients with liver tumors were prospectively enrolled. There were 61 men and 32 women with a mean age of 65.6 years. Fifty-nine patients had hepatocellular carcinoma and 34 had colorectal cancer liver metastases. Surgical strategy was based on the relationship between the tumor and intrahepatic vascular structures at IOUS. Rates of major and minor resection, mortality, morbidity, and rate of local recurrences were evaluated. RESULTS: There was no hospital mortality; major morbidity occurred in 2.2% of patients and minor complications in 17%. Six (6.5%) patients required blood transfusion. Major resections (two or more segments) were accomplished in 14 patients (15%), and 5 (5.4%) patients had more than three segments removed. Major vascular invasion was present in 16 patients (17%), and contact without infiltration with major vessels was present in another 16; part of the wall of the inferior vena cava was resected in 1 patient. Surgical clearance was achieved in all patients without local recurrence at a mean followup of 18 months (median 13, range 6 to 52 months). CONCLUSIONS: This study shows that liver operations performed under IOUS guidance are safe and radical and reduce need for major hepatectomies.  相似文献   
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Objectives

The aim of this review was to systematically evaluate the effects of autogenous platelet concentrates (PC) as an adjunct to the surgical treatment of periodontal defects.

Materials and methods

An electronic search was performed on MedLine, EmBase, and the Cochrane Central Register of Controlled Trials using specific search terms. A manual search of the main journals in the field of periodontology was also performed. Only randomized trials were included. The clinical attachment level was the primary outcome variable for periodontal intrabony defects. Root coverage and keratinized tissue increase was the main variable for gingival recession. For the statistical analysis all data were normalized to baseline values. The risk of bias of the included studies was also assessed. For intrabony defects, the influences of Guided Tissue Regeneration (GTR), of the study type (split-mouth vs parallel studies), and of the type of PC (Platelet Rich Plasma, PRP, vs Platelet Rich Fibrin, PRF) were also evaluated.

Results

Of the 456 studies initially retrieved, 48 were eligible and their full text was examined. Finally, 34 studies were included: 24 studies on periodontal intrabony defects, 7 studies on gingival recession, and 3 studies on furcation defects. A significant positive effect of the adjunct of PC was found for intrabony defects. Such an effect was magnified in studies in which GTR was not used, whereas in studies that used GTR, the use of PC had no adjunctive effect. No effect of the study type, of the follow-up duration or of the type of PC was observed. All split-mouth studies (except one in which GTR was used) displayed a significant positive effect of PC. No significant effect of PC was found for gingival recession treatment. Significant benefits of PC were reported for furcation treatment but, due to heterogeneity of the studies, no meta-analysis could be done.

Conclusions

The use of PC may exert a positive adjunctive effect for the treatment of intrabony defects when used in combination with graft materials, but not with GTR. No significant adjunctive benefit of PC could be demonstrated for the treatment of gingival recession and furcation defects. A standardization of study design and clinical protocols is needed in future studies in order to gain more insight into the true effect of PC in periodontal regeneration.  相似文献   
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