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41.

PURPOSE

To assess the retention of glass fiber post cemented with self-adhesive resin cement into optimum and over-prepared root canals following obturation in the presence of either eugenol (EB) or calcium hydroxide (CB)-based sealers.

MATERIALS AND METHODS

Roots of extracted premolars were endodontically-treated in 5 groups (n = 10). Roots of Group 1 (control) were left with no obturation and then optimally prepared to receive endodontic dowels. Other root canals were obturated with gutta-percha in the presence of either eugenol-based (Groups 2 and 4) or calcium hydroxide-based (Groups 3 and 5) sealer. Dowel spaces were prepared with optimal diameter in Groups 2 and 3, one size larger in Groups 4 and 5. Standardized fiber posts were luted to the prepared spaces using self-adhesive resin cement and itsretention was then tested on an universal testing machine. Both one-way ANOVA and Tukey''s HSD comparisons (α=0.05) were used to identifythe significance of inter-group retention differences. Scanning electron microscopy (SEM) of both optimally and over-prepared dowel spaces was also considered to figure the nature of their interior out.

RESULTS

The post retention was significantly higher to the non-obturated, optimally-prepared dowel spaces of Group 1 compared to the obturated, optimally-prepared ones of Groups 2 and 3. For each dowel space diameter, root canals obturated using CB of Groups 3 and 5 showed significantly higher dowel retention compared to those obturated using EB of Groups 2 and 4. Post retention to the over-prepared dowel spaces of Groups 4 and 5 was significantly higher than that recorded for the optimally-prepared ones of Groups 1-3. SEM images revealed traces of endodontic sealer and gutta-percha on the walls of the optimally-prepared dowel spaces.

CONCLUSION

Despite the adverse effect of endodontic sealers on the retention of fiber posts, the over-preparation of dowel spaces helps to improve the retention.  相似文献   
42.

Purpose

Sciatic nerve block (SNB) is commonly performed in combination with femoral nerve block (FNB) for postoperative analgesia following total knee arthroplasty (TKA). Despite the fact that 10–20 % of TKA patients require SNB for postoperative posterior knee pain, there are no existing studies that suggest a model to predict the need for SNB. The aim of our study was to develop a prediction tool to measure the likelihood of patients undergoing TKA surgery requiring a postoperative SNB.

Methods

With institutional review board approval, we obtained data from the electronic medical record of patients who underwent TKA at the Cleveland Clinic. A multivariable logistic regression was used to estimate the probability of requiring a postoperative SNB. Clinicians selected potential predictors to create a model, and the potential nonlinear association between continuous predictors and SNB was assessed using the restricted cubic spline model.

Results

In total 6279 TKA cases involving 2329 patients with complete datasets were used for building the prediction model, including 276 (12 %) patients who received a postoperative SNB and 2053 (88 %) patients who did not. The estimated C statistic of the prediction model was 0.64. The nomogram is used by first locating the patient position on each predictor variable scale, which has corresponding prognostic points. The cut-off of 11.6 % jointly maximizes the sensitivity and specificity.

Conclusion

This is the first study to be published on SNB prediction after TKA. Our nomogram may prove to be a useful tool for guiding physicians in terms of their decisions regarding SNB.
  相似文献   
43.

Background

The use of synthetic mesh for ventral hernia repair under contaminated conditions is a controversial issue due to the considerable risk of surgical site infection (SSI). This study aimed to review the outcomes of repair of incarcerated and strangulated ventral hernias with or without synthetic mesh in compliance with established clinical guidelines regarding the incidence of SSI and hernia recurrence.

Methods

The records of patients with complicated ventral hernias who were treated with or without synthetic mesh repair were reviewed. Variables collected included the characteristics of patients and of ventral hernias, type of repair, and incidence of SSI and recurrence.

Results

One hundred twenty-two patients (56 males) of a mean age of 56 years were included. Fifty-two (42.6%) and 70 (57.4%) patients presented with incarcerated and strangulated ventral hernias, respectively. Sixty-six (54%) patients were treated with on-lay mesh repair, and 56 (46%) were managed with suture repair. Twenty-one patients required bowel resection. SSI was detected in eight (6.5%) patients. There was no significant difference between both groups regarding the incidence of SSI (7.5% for mesh group vs 5.3% for suture group). Recurrence occurred in seven patients. Median follow-up period was 24 months. The suture repair group had a significantly higher incidence of recurrence than the mesh group. Diabetes mellitus, previous recurrence, and intestinal resection were significant predictors for SSI.

Conclusion

Following established guidelines, synthetic mesh repair of incarcerated and strangulated ventral hernias attained lower recurrence rate, comparable incidence of SSI, and higher rate of seroma formation than suture repair.

Trial registration

Research Registry, researchregistry1891
  相似文献   
44.
45.
Objective To describe our experience of cerebrospinal fluid (CSF) rhinorrhea management.Design Retrospective.Setting Charing Cross Hospital, London, a tertiary referral center.Participants Fifty-four patients with CSF rhinorrhea managed from 2003 to 2011.Main outcome measures Surgical technique; Recurrence.Results Etiologically, 36 were spontaneous and 18 traumatic. Eight patients with spontaneous and two with traumatic leaks had previous failed repairs in other units. Success rates after first and second surgery were 93% and 100%, respectively. Mean follow-up was 21 months. Four patients, all of spontaneous etiology, had recurrences; three of these underwent successful second repair with three layered technique, and the fourth had complete cessation of the leak after gastric bypass surgery and subsequent weight reduction. Adaptation of anatomic three-layered repair since then averted any further failure in the following 7 years. Mean body mass index was 34.0 kg/m2 in spontaneous and 27.8 kg/m2 in traumatic cases (p < 0.05). Fifty percent of spontaneous leaks were from the cribriform plate, 22% sphenoid, 14% ethmoid, and 14% frontal sinus. In the traumatic CSF leak group: 33.3% were from the cribriform plate, 33.3% sphenoid, 22.2% ethmoid, and 11.1% frontal.Conclusion Endoscopic CSF fistula closure is a safe and effective operation. All sites of leak can be accessed endoscopically. We recommend the use of an anatomic three-layered closure in difficult cases.  相似文献   
46.
47.

Background

Because perioperative complications of unrecognized obstructive sleep apnea (OSA) can be severe, many bariatric surgery programs routinely screen all patients. However, many obese non-bariatric surgery patients do not get screened. We wanted to evaluate the need for routine preoperative OSA screening.

Methods

Morbidly obese patients with a body mass index (BMI)?>?40 kg/m2 undergoing bariatric surgery—all screened for OSA—were compared to morbidly obese orthopedic lower extremity total joint replacements (TJR) patients—not screened for OSA. Cardio-pulmonary complications were recorded.

Results

Eight hundred eighty-two morbidly obese patients undergoing either bariatric (n?=?467) or orthopedic TJR surgery (n?=?415) were compared. As a result of screening, 119 bariatric surgery patients (25.5 %) were newly diagnosed with OSA, bringing the incidence to 42.8 % (200/467). Orthopedic surgery group had 72 of 415 (17.3 %) patients with pre-existing OSA. The unscreened orthopedic patients had a 6.7 % (23/343) cardiopulmonary complications rate compared to 2.6 % (7/267) for screened bariatric surgery patients. This difference was not statistically significant when adjusted for age and comorbidity (p?=?0.3383).

Conclusion

Sleep apnea screening prior to bariatric surgery identifies an additional 25 % of patients as having OSA. In this study, unscreened morbidly obese patients did not have an increased incidence of cardiopulmonary complications after surgery compared to screened patients. Prospective randomized studies should be conducted to definitively assess utility and cost effectiveness of routine OSA screening of all morbidly obese patients undergoing surgery. Preoperative OSA screening may be safely omitted when randomizing patients for such a trial.  相似文献   
48.
49.

Background

Greater trochanteric fracture/nonunion can be a devastating complication with significant functional impact after total hip arthroplasty, and their fixation remains a challenge because of the significant forces being transmitted as well as the poor bone quality often associated with these fractures. The objective of this study is to investigate the rates of reoperation and trochanteric nonunion using a third-generation cable-plate system at one center.

Methods

Thirty-five patients, mean age 72.9 years (range 46-98 years) with 24 women and 11 men, underwent fixation of their fractured greater trochanter using a third-generation cable-plate system. The indications were: periprosthetic fracture (n = 17), complex primary arthroplasty (n = 5), and complex revision arthroplasty (n = 13). Primary outcomes included rates of reoperation and radiographic union.

Results

At a mean follow-up of 2.5 years, trochanteric union rate was 62.9% with nonunion rate of 31.4%, and fibrous union in 5.7%. In regard to quality of initial apposition, only 40% achieved a perfect bone on bone reduction. Ten patients (28.6%) had evidence of wire breakage. Five patients (14.3%) required reoperation and removal of the internal fixation because of lateral hip pain.

Conclusion

Fixation of the trochanteric fractures remains a challenge with a relatively high reoperation rate. Poor bone quality and capacity to maintain a stable reduction continue to make this complication after total hip arthroplasty a difficult problem to solve.  相似文献   
50.
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