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61.
Background: The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two‐implant overdenture has been recommended as the standard of care. The use of small‐diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable. Purpose: This randomized, controlled, double‐blind, multicenter study investigated in a split‐mouth model whether small‐diameter implants made from Titanium‐13Zirconium alloy (TiZr, Roxolid?) perform at least as well as Titanium Grade IV implants. Methods and Materials: Patients with an edentulous mandible received one TiZr and one Ti Grade IV small‐diameter bone level implant (3.3 mm, SLActive®) in the interforaminal region. The site distribution was randomized and double‐blinded. Outcome measures included change in radiological peri‐implant bone level from surgery to 12 months post‐insertion (primary), implant survival, success, soft tissue conditions, and safety (secondary). Results: Of 91 treated patients, 87 were available for the 12‐month follow‐up. Peri‐implant bone level change (?0.3 ± 0.5 mm vs ?0.3 ± 0.6 mm), plaque, and sulcus bleeding indices were not significantly different between TiZr and Ti Grade IV implants. Implant survival rates were 98.9 percent and 97.8 percent, success rates were 96.6 percent and 94.4 percent, respectively. Nineteen minor and no serious adverse events were related to the study devices. Conclusion: This study confirms that TiZr small‐diameter bone level implants provide at least the same outcomes after 12 months as Ti Grade IV bone level implants. The improved mechanical properties of TiZr implants may extend implant therapy to more challenging clinical situations.  相似文献   
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63.
Background: Studies have pointed out that the mere elevation of the maxillary sinus membrane might suffice to allow for bone formation indicating the additional use of augmentation materials to be redundant. Purpose: The purpose of this study was to assess whether elevation of the sinus mucosal lining combined with applying an autologous bone graft as a ceiling and placement of a short implant would allow for bone formation around the implant thus surpassing the need for applying augmentation materials around the installed implants. Materials and Methods: Fourteen consecutive patients were subjected to maxillary sinus floor elevation surgery and simultaneous placement of an implant. Using the lateral bone‐wall window technique, the membrane was exposed and elevated. Next, a bone graft taken from the zygomatic rim was placed as a ceiling above the inserted implant to ensure that the sinus membrane would not collapsed around a significant part of the implant. Finally, the bone window was returned in place. After connecting the healing abutment, the wound was closed. Results: All implants were stable and no implants were lost. There were no complications after harvesting the bone graft. Radiographic evaluation showed a bone gain of 3.2 ± 0.9 mm after 3 months and 3.6 ± 0.9 mm after 1 year. Less than 6% of the implant was not covered by bone after 1 year. Conclusion: Maxillary sinus membrane elevation and simultaneous placement of short endosseous implants with a bone graft as a ceiling on top of the implant result in predictable bone formation around the implant and good osseointegration on radiographs.  相似文献   
64.
Purpose: This multicenter case series evaluates retrospectively the clinical outcomes of malpositioned implants surgically relocated in a more convenient position by segmental osteotomies. Materials and Methods: Authors who published, on indexed journals or books, works about malpositioned implant correction by segmental osteotomies were contacted. Five centers, out of 11 selected, accepted to participate in this study. The dental records of patients who underwent implant relocation procedures were reviewed. Implant survival rates were analyzed and a blinded assessor examined clinical photos and periapical radiographs to evaluate esthetic outcome (pink esthetic score [PES]) and changes of marginal bone level over time. Patients were requested to fill a verbal rating scale form about discomfort, compliance, and satisfaction related to the procedure. Results: Fifteen malpositioned implants relocated by segmental osteotomies were followed for a period ranging from 1 to 15 years (mean 6.0 ± 3.9 years). The overall implant survival rate from baseline to the last follow‐up visit was 100%. The mean marginal bone loss was 0.36 mm at the 12‐month follow‐up visit and no relevant further changes were observed at the following examinations. Significant esthetic improvement was recorded at 1‐year examination with PES evaluation (p < .0001). Patients' feedback described this procedure as not excessively invasive and uncomfortable, reporting a high final satisfaction rate. Conclusions: The present study suggests that implant relocation with segmental osteotomies could be an effective alternative method to correct the position of unrestorable malpositioned implants in a single‐stage surgery.  相似文献   
65.

Background

Traumatic brain injury is common. Guidelines from the Brain Trauma Foundation and the Scottish Intercollegiate Guidelines Network recommend that patients with suspected severe traumatic brain injury should be treated in centres with neurosurgical expertise. Scotland does not have a framework for the delivery of trauma care. The aim of this study was to examine the demographic characteristics of incidents involving patients who have suffered a suspected traumatic brain injury, and to evaluate the level of the destination healthcare facility which patients are currently taken to.

Methods

Retrospective analysis of prospectively collected Scottish Ambulance Service data on incidents involving traumatic injury, between Nov 2008 and Oct 2010. Two groups of casualties were analysed: those who had a Glasgow coma scale of less than 14 (GCS < 14), and those who had a Glasgow coma scale of less than 9 (GCS < 9).

Results

126,934 incidents were identified and analysed. 3890 (3.1%) patients had a GCS of less than 14, and 657 (0.5% of total) had a GCS of less than 9. Almost one-third of incidents involving patients with either a GCS < 14 or GCS < 9 occurred in the greater Glasgow health board area. The Lothian health board region had the second-highest number of patients with either a GCS < 14 or GCS < 9. Only 13.8% of patients with a GCS < 14, and 16.7% of those with a GCS < 9, were taken to a hospital with a neurosurgical service.

Conclusions

Many patients who may harbour a traumatic brain injury are taken to a facility which may not be equipped or staffed to deal with such injuries. This mismatch needs to be addressed. However, the care of patients with head injuries is only one aspect of trauma care. The UK has long lagged behind North America in terms of the quality of trauma care provided, although the provision of trauma care in England is currently undergoing major changes. Scotland should consider the development of a similar service delivery framework.  相似文献   
66.
口咽通气导管为一种非气管导管性通气管道,其操作简便,易于掌握,不需要特殊器械能在数秒钟内迅速获得有效通气,并保持呼吸道通畅,在抢救危重、昏迷患者过程中发挥着重要的作用[1].但传统口咽通气导管使用中因不易固定,容易全部滑入患者口腔,有并发食管、气管异物,引起患者误吸、窒息甚至危及患者生命的危险[2].为此,我科对传统口咽通气导管进行改良,介绍如下.  相似文献   
67.
The profession of dental therapy has long been held up as a model for reducing access to care barriers in high-risk, underserved populations worldwide. Dental therapists practice in many countries delivering preventive and basic restorative care to children and adults. In North America, dental therapy education and practice date back to 1972 with the establishment of training programs at the National School of Dental Therapy in Fort Smith, Northwest Territories, and the Wascana Institute of Applied Arts and Science in Regina, Saskatchewan, as a means of reducing access to care barriers in Canada's northern territories and to implement the Saskatchewan Health Dental Plan, respectively. At present, dental therapy in North America has reached a crossroads: in the United States, the profession is cautiously being explored as a solution for improving access to care in at-risk populations. In 2011, Canada's sole training program, the National School of Dental Therapy in Prince Albert, Saskatchewan, closed when the federal government eliminated its funding. This article examines the impact of private practice employment of dental therapists in Saskatchewan on the supply of dental therapist human resources for health in Canada's three northern territories (Northwest Territories, Nunavut, and Yukon), its role in the closure of the National School of Dental Therapy in 2011, and ramifications for the future of dental therapy in Canada.  相似文献   
68.
Implant-supported overdentures are a good alternative for patients with conventional dentures that lack retention and stability. The most common prosthetic complications in mandibular and maxillary implant-supported overdentures are fracture and loosening of the attachment system. This clinical report describes the treatment of a completely edentulous patient with sinus floor elevation by using bone from the iliac crest and the insertion of 4 implants in the maxilla and mandible followed by implant-supported overdentures. The technical procedure for the attachment of clips to an acrylic resin overdenture base with the use of metal reinforcement is described. The advantage of this attachment procedure is an improved attachment system with less fracture and less loosening of the clips.  相似文献   
69.
Background: Despite the widespread use of the Impact of Event Scale to measure post-traumatic stress symptoms, psychometric evaluations of the scale have revealed mixed findings. Aim: The aim of the present study is to provide new empirical evidence and examine the factor structure, reliability, and predictive validity of the Norwegian version of the IES-R. Methods: Posttraumatic stress symptoms were recorded in a student sample (n=312) 3 weeks after the Southeast Asian tsunami disaster in December 2004. Confirmatory factor analyses of the IES-R behavior items using structural equation modeling (SEM) were performed on four models from existing research. Results: The original three-factor model of intrusion, avoidance and hyperarousal symptoms exhibited the best goodness-of-fit indices when defined as oblique. The IES-R also revealed satisfactory reliability. Symptom levels of intrusion and avoidance were moderate, while hyperarousal scores were low, with a significant gender difference. Conclusion: Taken together, the IES-R revealed good psychometric properties in this nonclinical student sample and could be a useful instrument to assess and follow-up on PTSD symptoms after a certain identified trauma.  相似文献   
70.
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