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41.
Cerebrovascular accident (CVA) is the third cause of death in industrialized countries, following cardiovascular disease and cancer. It is therefore a significant public health issue, not only due to its high incidence, but also to the high costs involved in the physical and psychological rehabilitation of these patients. Dental Practitioners, as health care providers, ought to play their part in this issue and contribute, within their means, to the early detection of patients at risk of having a CVA. Since the eighties, different authors have described the possibility of detecting calcified atheroma plaques located at carotid artery bifurcation through panoramic radiograph. In this way, the Dental Practitioner s possibilities in this field have been extended. However, this new use of panoramic radiograph must overcome certain obstacles before it is implemented as a new screening method for patients at risk of having a CVA. Amongst these, we would have, on the one hand, the assessment of the real clinical significance, as regards prognosis, of atheroma plaque calcification as well as its usefulness as a factor for predicting the appearance of CVA symptoms and, on the other hand, the possibility of making a correct differential diagnosis regarding other calcified structures that may appear on panoramic radiograph.  相似文献   
42.

Introduction

The purpose of this study was firstly to compare the impact of radiographs, cone-beam computed tomographic (CBCT) imaging, and 3D Endo software (Dentsply Sirona, Ballaigues, Switzerland) on the assessment of root canal anatomy and radiographic quality of endodontic treatment and secondly to assess stress levels in the same cohort of residents performing endodontic treatment.

Methods

Sixty patients requiring primary molar endodontic treatment were allocated randomly into 3 groups: group 1 (n = 20), conventional radiographs (periapical radiography [PR]) only; group 2 (n = 20), PR and CBCT imaging; and group 3 (n = 20), PR, CBCT imaging, and 3D Endo software. All treatment was performed using a standardized protocol. Residents completed a questionnaire to assess their stress levels and usefulness of the imaging modality used. The radiographic quality of completed cases was assessed by 2 experienced endodontists who were not involved in the supervision of the cases being assessed.

Results

Groups 2 (CBCT imaging) and 3 (PR, CBCT imaging, and 3D Endo) proved significantly better than group 1 (PR) (P < .001) for assessing the number of root canals and anatomy and estimating the working lengths. Group 3 provided a significantly more accurate determination of the working level (P = .002). There were significantly more cases with obturation short of the apex (<2 mm) and voids in group 1 compared with group 3 (P < .05) and a significantly higher number of cases with voids in group 1 compared with group 3 (P < .01). Clinicians found treatment to be moderately or very stressful in 75%, 5%, and 0% in groups 1, 2, and 3, respectively.

Conclusions

3D Endo software followed by CBCT imaging were found to be more desirable for the evaluation of root canal anatomy and working lengths and reducing the residents' stress levels.  相似文献   
43.
Abstract The purpose of this study was to describe by age and sex, the prevalence, etiology, distribution and type of injury to permanent incisors of children from private schools of Santo Domingo, Dominican Republic, located in the Caribbean archipelago. The sample consisted of 1633 children, 5–14 yr enrolled in several private schools of Santo Domingo. The prevalence of injury was 10.0% (5.0% in boys and 5.1 % in girls). The largest number of injuries was found in the 5- and 6-yr-old children, followed by the 7- and 8-yr-olds. There was no significant difference in the number of teeth injured in both sexes (0.1 %). The most common type of injury in both sexes was concussion (42.7%) with no significant difference between sexes (5.7%). The most common cause of injury in both sexes was falling against an object (77.8% in boys and 78.3% in girls). Most boys injured their teeth playing baseball (86.4%) and most girls playing on roller skates (72.3%). More girls suffered injuries (not significantly) with the ratio of boys to girls being 0.91 to 1.  相似文献   
44.
PURPOSE: The aim of the present study was to evaluate the concept of an immediate loading protocol in the posterior maxilla and mandible through analysis of implant survival at 1 year. MATERIALS AND METHODS: One year follow-up data of a multicenter study are reported. Eighty-two ITI sandblasted, acid-etched (SLA) implants in 40 patients were loaded between 0 and 11 days after implant placement (mean 4.3 +/- 2.8 days). The restorations consisted of either 2 splinted crowns or a 3-unit fixed prosthesis. All restorations were put into full functional occlusion. Periapical radiographs were evaluated for changes in crestal bone level from baseline to 1 year postloading. Primary stability of the implants was checked initially and before the fitting of the definitive prosthesis. The restorations were evaluated by the practitioners for retention, stability, and esthetics. RESULTS: Three patients' implants were not loaded because of lack of primary stability, and a fourth patient was excluded from the study because of a protocol violation (more than 4 implants were used). All 4 patients were successfully treated outside the protocol. The overall survival rate of the remaining implants at 1 year was 98.8%. The mean bone loss at 1 year was 0.52 +/- 0.98 mm, which is within the reported limits of less than 1 mm (range 0.4 to 1.4 mm) loss in the first year. DISCUSSION AND CONCLUSION: The early results from this study indicate that early and immediate loading of 2 implants in the posterior maxilla and mandible may be suitable in selected patients. On the basis of 1 year of observation, the results appear similar to those achieved with a delayed procedure.  相似文献   
45.
OBJECTIVE: To compare skeletal maturation as measured by hand-wrist bone analysis and by cervical vertebral analysis. MATERIALS AND METHODS: A radiographic hand-wrist bone analysis and cephalometric cervical vertebral analysis of 30 patients (14 males and 16 females; 7-18 years of age) were examined. The hand-wrist bone analysis was evaluated by the Bjork index, whereas the cervical vertebral analysis was assessed by the cervical vertebral maturation stage (CVMS) method. To define vertebral stages, the analysis consisted of both cephalometric (13 points) and morphologic evaluation of three cervical vertebrae (concavity of second, third, and fourth vertebrae and shape of third and fourth vertebrae). These measurements were then compared with the hand-wrist bone analysis, and the results were statistically analyzed by the Cohen kappa concordance index. The same procedure was repeated after 6 months and showed identical results. RESULTS: The Cohen kappa index obtained (mean +/- SD) was 0.783 +/- 0.098, which is in the significant range. The results show a concordance of 83.3%, considering that the estimated percentage for each case is 23.3%. The results also show a correlation of CVMS I with Bjork stages 1-3 (interval A), CVMS II with Bjork stage 4 (interval B), CVMS III with Bjork stage 5 (interval C), CVMS IV with Bjork stages 6 and 7 (interval D), and CVMS V with Bjork stages 8 and 9 (interval E). CONCLUSIONS: Vertebral analysis on a lateral cephalogram is as valid as the hand-wrist bone analysis with the advantage of reducing the radiation exposure of growing subjects.  相似文献   
46.
Objective: To determine if longitudinal bone level change at Astra Tech? implants placed in the posterior part of the dentition was influenced by the healing conditions provided following implant placement, i.e., submerged or non‐submerged healing. Material and methods: Eighty‐four patients and 115 fixed partial dentures (FPDs or cases) entered the study. The cases were randomized into two implant installation groups: initially non‐submerged (group A) or initially submerged (group B) implants. Three hundred and twenty‐four implants were installed (group A=153; group B=171): 145 in the maxilla and 179 in the mandible. Radiographs from the implant sites were obtained at FPD insertion (baseline) and subsequently every 12 months. In the radiographs, the position of the marginal bone at the mesial and distal aspects of the implants was determined and the radiographic (Rx) bone level change over time was calculated. Results: Seven implants failed to integrate (four in group A and three in group B). During the 5 years of monitoring, three implants had to be removed and 35 implants were lost to follow‐up. The Rx bone level alteration that occurred during year 1 was 0.02±0.38 mm in group A and 0.17±0.51 mm in group B. During the subsequent 4 years there was some further Rx bone loss in group B (0.02±0.62 mm), while in group A there was some gain of bone (0.07±0.5 mm). Conclusion: The peri‐implant bone level change and number of biological complications that took place during the 5 years was small and unrelated to the surgical protocol used for implant placement.  相似文献   
47.
Transcranial magnetic stimulation (TMS) studies on the pathways to the upper limbs have revealed inconsistent results in patients harboring mutations in SPAST/SPG4 gene, responsible for the commonest form of hereditary spastic paraplegia (HSP). This paper is addressed to study the corticomotor excitability of the pathways to the upper limbs in SPG4 subjects. We assessed the corticomotor excitability of hand muscles in 12 subjects belonging to 7 unrelated SPG4 families and in 12 control subjects by stimulus–response curve [input–output (I–O) curve]. All the parameters of the recruitment curve (threshold, V50, slope and plateau) did not differ significantly from those of the controls. Presence of upper limb hyper-reflexia did not influence the results of I–O curve. Considering the multiplicity of possible genes/loci accounting for pure HSPs, performing TMS analyses could be helpful in differential diagnosis of pure HSPs in the absence of other clinical or neuroimaging tools.  相似文献   
48.
49.
Transplant recipients receiving immunosuppressive therapy are at increased risk of active cytomegalovirus (CMV) infection and disease. Without appropriate prophylaxis, as many as 80% of solid organ transplant recipients may experience CMV infection. In addition to the direct effects of CMV, infection may be associated with a range of indirect effects, including an increase in risk of other infections, as well as a higher incidence of rejection, graft loss and death. The indirect effects of CMV infection can vary depending on the transplanted organ. For example, CMV-infected kidney transplant recipients may be at increased risk of cardiovascular disease and diabetes, while CMV infection in liver transplant recipients may potentiate hepatitis C infection and increase the risk of post-transplant lymphoproliferative disease. Indirect effects result from a number of pathological processes, including immune modulation and immunosuppression, generation of cytotoxic, pro-inflammatory responses, and smooth muscle proliferation. Prophylactic treatment with antiviral medication can reduce the risk of CMV disease, thereby improving graft survival and overall outcomes, particularly in kidney and heart transplant recipients. Antiviral prophylaxis should be considered for all patients at risk of CMV infection after solid organ transplantation. In this paper we review the main indirect effects of CMV infection in solid organ transplant recipients, and the impact of CMV prophylaxis on these effects.  相似文献   
50.
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