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991.
Gingival recession beyond grade III and grade IV level involving furcation defects can lead to tooth loss if not intervened at appropriate time. The treatment options include scaling and root planing, Furcation-plasty, Tunnel preparation, Root separation and resection. The chief complaint of the patient was pain in the upper left first molar because of grade III furcation involvement. Since it was a four rooted molar, the treatment of choice was hemisection of the tooth and extraction of the distal half following endodontic treatment. As the second molar was mesially tilted the prosthodontic rehabilitation was done with a hybrid prosthesis involving a full coverage conventional porcelain fused to metal retainer on the hemisected molar and a resin bonded partial coverage retainer on the tilted second molar. The resultant prosthesis is termed as "Hybrid prosthesis".  相似文献   
992.
Soft denture liners act as a cushion for the denture bearing mucosa through even distribution of functional load, avoiding local stress concentrations and improving retention of dentures there by providing comfort to the patient. The objective of the present study was to compare and evaluate the tensile bond strengths of silicone-based soft lining materials (Ufi Gel P and GC Reline soft) with different surface pre treatments of heat cure PMMA denture base acrylic resin. Stainless steel dies measuring 40 mm in length; 10 mm in width and 10 mm in height (40 × 10 × 10) were machined to prepare standardized for the polymethyl methacrylate resin blocks. Stainless steel dies (spacer for resilient liner) measuring 3 mm thick; 10 mm long and 10 mm wide were prepared as spacers to ensure uniformity of the soft liner being tested. Two types of Addition silicone-based soft lining materials (room temperature polymerised soft lining materials (RTPSLM): Ufi Gel P and GC Reline soft) were selected. Ufi Gel P (VOCO, Germany), GC Reline soft (GC America) are resilient, chairside vinyl polysiloxane denture reliners of two different manufacturers. A total of 80 test samples were prepared of which 40 specimens were prepared for Group A (Ufi Gel P) and 40 specimens for Group B (GC Reline soft). In these groups, based on Pre-treatment of acrylic resin specimens each group was subdivided into four sub groups of 10 samples each. Sub-group I—without any surface treatment. Sub-group II—sand blasted Sub-group III—treated with Methyl Methacrylate monomer Sub-group IV-treated with chemical etchant Acetone. The results were statistically analysed by Kruscal Wallis test, Mann–Whitney U test, and Independent t test. The specimens treated with MMA monomer wetting showed superior and significant bond strength than those obtained by other surface treatments. The samples belonging to subgroups of GC Reline soft exhibit superior tensile bond strength than subgroups of Ufi Gel P. The modes of failure of all specimens were mostly adhesive in nature. Surface pre treatments by chemical means improved the bond strength between the silicone liners and denture base.  相似文献   
993.
The major connector is the most vital component critically subjected to maximal stress concentration due to various forces acting on it. The main requirement of a major connector is its resistance to deformation by occlusal stresses. This resistance to deformation is a direct consequence of the rigidity of the major connector. Thus rigidity of the major connector is paramount to resist flexing and torquing forces that could be transmitted to the abutment teeth and other structures as destructive forces. The commonly used major connectors for the mandibular arch are lingual bar and lingual plate. In the present study, the deflection of various major connector designs due to occlusal load is assessed by finite element method. They have been analyzed through finite element models. The differences in the deflection behaviour of mandibular major connector used in Kennedy’s Class I, Class II, Class III, and Class IV edentulous situations have been compared. A CT scan of human edentulous mandible was taken and each section from symphysis to condylar region was projected on a graph paper and three-dimensional volumes were created from connected successive profiles to define the final solid geometry of cortical bone. Six framework models with different mandibular major connectors, lingual bar and lingual plate for Kennedy’s Class I, Class II, Class III, and Class IV situations were created. The three dimensional finite element models corresponding to the geometric model were generated using Ansys’s pre-processor. The model was assigned material properties. A vertical biting force of 20 N was applied. The results showed that the maximum deflection was seen in the saddle area when compared to other areas, i.e., major connector and the occlusal rest regions. The lingual bar in Kennedy’s Class III situation and lingual plate in Kennedy’s Class IV situation showed the least deflection when compared to Class I and Class II (distal extensions) situations. Lingual plate is more rigid major connector than lingual bar.  相似文献   
994.
ObjectiveTo evaluate the efficacy and complications of lower eyelid suspension with the modified Safdarjung hospital technique using 5:0 polypropylene suture for punctal ectropion.Study designProspective case series.MethodThirty one eyelids in 19 patients with mild and moderate ectropion and all types of laxity including involutional and paralytic were included. All patients underwent lower eyelid suspension with the modified Safdarjung hospital technique. A 5:0 polypropylene suture was passed in the pre-tarsal plane between the attachments of the lateral and medial canthal tendons near their insertion at the orbital rim. Successful outcome was judged by the anatomical restoration of the apposition of the punctum to the globe in the upward gaze and the physiological relief of epiphora. The recurrence of lid laxity, overall lid/globe apposition and complications were also noted.ResultsAt 1 year follow up anatomical success was achieved in 28 (90%) patients and functional success noted in 27 (87%) patients. Recurrence of lid laxity was noted in 2 patients. There was a suture exposure in one case and a suture granuloma in another case. The results did not correlate to the degree of ectropion and type of laxity.ConclusionLower eyelid suspension using 5:0 polypropylene suture is a useful procedure for the treatment of involutional and paralytic punctal ectropion. It is simple and effective with minimal complications. However, the effect on scleral show and the concern related to suture material biodegradation over years needs to be further evaluated.  相似文献   
995.
Purpose: To assess the efficacy and safety of once‐daily doses of perampanel 8 and 12 mg when added to 1–3 concomitantly administered, approved antiepileptic drugs (AEDs) in patients with uncontrolled partial‐onset seizures. Methods: Study 305 was a multicenter, double‐blind, placebo‐controlled trial in patients aged 12 years and older with ongoing seizures despite prior therapy with at least two AEDs, and currently receiving 1–3 AEDs. Equal randomization to once‐daily oral perampanel 8 or 12 mg, or placebo was performed. Patients entered a 19‐week double‐blind treatment phase comprising a 6‐week titration period, with weekly 2‐mg dose increments, followed by a 13‐week maintenance period. Primary efficacy end points were the responder rate (proportion of patients who had a ≥50% reduction in seizure frequency during treatment per 28 days relative to baseline), and the percent change in seizure frequency per 28 days relative to pre‐perampanel baseline. A secondary end point was percent change in the frequency of complex partial plus secondarily generalized seizures. Adverse events (AEs) were monitored throughout the study. Key Findings: Three hundred eighty‐six patients were randomized and treated with study medication. Of these, 321 patients completed the study. The 50% responder rates (intent‐to‐treat analysis) were 14.7%, 33.3%, and 33.9%, respectively, for placebo, perampanel 8 mg, and perampanel 12 mg, with significant improvements over placebo for both perampanel 8 mg (p = 0.002) and 12 mg (p < 0.001). The median percent change from baseline in seizure frequency per 28 days (intent‐to‐treat analysis) was ?9.7%, ?30.5%, and ?17.6% for placebo, 8 mg, and 12 mg, respectively, with significant reductions compared with placebo for both 8 mg (p < 0.001) and 12 mg (p = 0.011). For complex partial seizures plus partial seizures that secondarily generalized, the median percent change in frequency was ?32.7% (8 mg), ?21.9 (12 mg), and ?8.1% (placebo), with significant reductions for both 8 mg (p < 0.001) and 12 mg (p = 0.005). The most frequent (occurring in ≥10% of patients in any treatment group) treatment‐emergent AEs were dizziness, somnolence, fatigue, and headache, with an apparent dose effect suggested for all except headache. Significance: This phase III trial demonstrated that adjunctive treatment with once‐daily perampanel at 8 mg and 12 mg was effective in improving seizure control in patients 12 years and older with refractory partial‐onset seizures. These study results also demonstrated that once‐daily doses of 8 mg and 12 mg were safe and acceptably tolerated in this study. Perampanel demonstrated a favorable risk/benefit ratio in this population.  相似文献   
996.

Background

Hydrocephalus of tubercular origin is one of the most dreaded and difficult to manage complications of brain tuberculosis. Traditionally, the management has been ventriculoperitoneal shunting, but in recent years emerging interest is in endoscopic ventriculostomy. In this article, we discuss the management protocol of hydrocephalus in various stages of disease.

Methods

A total of 424 cases of tubercular origin hydrocephalus were managed between years 2000 and 2009. Initially the cases were managed by ventriculoperitoneal shunting, which was followed by use of endoscopic third ventriculostomy. Drug-resistant cases were also encountered and managed according to drug sensitivity.

Results

The results provided through evaluation of retrospective data showed a high mortality in cases of hydrocephalus of acute origin if endoscopic third ventriculostomy was performed. The cerebrospinal fluid protein level and neurological status of the patient determined the success or failure of the procedure. For better management, patients were divided into six groups and their management underlined.

Conclusion

The cases of tubercular meningitis with aqueductal stenosis presenting in early stages should be given a trial of endoscopic third ventriculostomy where chronic burnt-out cases or cases with communicating hydrocephalus should be managed by ventriculoperitoneal shunting.  相似文献   
997.
998.

Background:

Bleeding during total knee arthroplasty (TKA) can cause significant morbidity and mortality. One proposed benefit of computer assisted TKA is decreased bleeding as the femoral canal is not invaded. This study assessed blood loss between computer assisted surgery (CAS) and conventional TKA.

Materials and Methods:

73 consecutive patients (37 males, 36 females) underwent primary TKA between 2006 and 2009. Thirty eight patients underwent navigated TKA and 35 underwent conventional TKA for symptomatic osteoarthritis of the knee. These patients were matched for age, gender, and body mass index (BMI). Average age was 70.3 years (range 47-91 years). Mean BMI was 30 (range 17-49). Average preoperative hemoglobin was 13.26 g/dL (range 8.7-18.4 g/dL) in the navigated group and 13.47 g/dL (range 9.6-15.8 g/dL) in the conventional group (P = 0.9). Average tourniquet time was 110 min (range 90-150 min) in the navigated group and 96.7 min (range 60-145 min) in the conventional group (P = 0.77).

Results:

Average postoperative hemoglobin in the navigated group was 10.34 g/dL (range 7.5-14.8 g/dL) and in the conventional group was 10.03 g/dL (range 7.5-12.2 g/dL) (P = 0.17). Six patients in both groups required blood transfusions. The mean drain collection was 599 mL (range 150-1370 mL) in the navigated group and 562 mL (range 750-1000 mL) in the conventional group (P = 0.1724). These results suggest that there is no significant reduction in blood loss in CAS TKA.

Conclusion:

These results suggest that there is no significant difference in blood loss in CAS TKA and conventional TKA. This study also highlights the heterogeneity of methods used in studies related to CAS TKA. We believe that there is a need for a large multicenter prospective randomized controlled trial to be performed before a consensus can be reached on the influence of CAS techniques on blood loss during primary TKA.  相似文献   
999.
1000.
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