Model Features of a Cardiac lontophoretic Drug Delivery Implant

Pharmaceutical Research -     

Resection and augmentation of Bichat's fat pad in facial contouring

Summary The Bichat's fat pad (Corpus adiposum buccae) is of great significance in facial contouring. Resection of major parts of this fat pad results in hollow cheeks and in accentuation of the zygoma. On the other hand, hypoplasia or shrinkage of this fat pad can be augmented by means of silicone implants for improved aesthetic results.     

Medpor义眼座置入同期放置钛钉治疗眼眶凹陷畸形

目的探讨Medpor义眼座植入同期放置钛钉治疗眼球摘除术后眼眶凹陷畸形的有效性和可行性。方法眼球摘除同期置入Medpor义眼座患者80例，随机分为钛钉Ⅰ期置入组和Ⅱ期置入组，每组各40例。比较两组患者术中、术后出现的并发症和患者对义眼活动度和外观的满意程度。结果40例Ⅰ期置入患者术中有37例在术后2～6周时钛钉尾端自发性暴露，只有3例患者需要剪开结膜使钛钉尾端暴露。术后出现并发症者共37例，占46％：其中Ⅰ期置入组17例，Ⅱ期置入组加例，两者差异无统计学意义（P=0．501）。所有患者对其外观和活动度满意，其中Ⅰ期置入组非常满意36例，比较满意4例；Ⅱ期置入组非常满意34例，比较满意6例，两者差异无统计学意义（P=0．502）。结论Medpor义眼座置入同期放置钛钉治疗眼球摘除术后眼眶凹陷畸形，是一种安全有效的手术方法，同时患者避免了再次手术的痛苦。     

钛种植体－羟基磷灰石早期修复犬下颌骨缺损与骨结合的实验研究

本研究对钛种植体－羟基磷灰石（Ｔｉ－ＨＡ）在早期修复下颌骨缺损中与骨结合的界面形态进行了扫描电镜和Ｘ线能谱观察分析。通过对９只健康狗下颌骨缺损区植入Ｔｉ－ＨＡ２、６及１２周后Ｔｉ－ＨＡ／宿主骨界面及Ｔｉ／ＨＡ界面的扫描电镜观察和Ｘ线能谱分析，结果表明Ｔｉ－ＨＡ植入骨缺损区，不引起正常的骨矿化过程改变，与宿主骨形成骨性结合；Ｔｉ／ＨＡ界面有新骨形成；扫描电镜观察和Ｘ线能谱分析在研究骨缺损修复过程中不同阶段的组织成份的变化是一个重要手段。     

Spiral-shaped Metallic Implant in the Treatment of Achilles Tendon Ruptures: An Experimental Study on the Achilles Tendon of Sheep

There are 2 main factors contributing to the strength of tendon repair: the tensile strength of the material used in repair and the tendon-holding capacity of the suture configuration. In the current study, we aimed to find a technique with high repair strength by increasing both the tensile strength of the material and the tendon-holding capacity of the configuration. We developed metal implants (models 1 and 2) made from stainless-steel wire with 2 different spiral-shaped configurations. We measured tendon-holding capacities of these alternative implants biomechanically and compared them with frequently used suture techniques, the Bunnell and locking loop, which were achieved with 5 Ticron sutures. Sixty-four sheep Achilles' tendons were used in the study as 16 tendons in each group. Model 2 was more resistant to deformation under loading when compared with model 1. The results demonstrated that model 2 was superior to model 1 and both suture techniques. This study could be accepted as a step for reaching a strong tendon repair technique. It should be emphasized that the technique needs to be improved technically to make it convenient for clinical use.     

钛合金板置入在颅骨缺损修复中的应用

目的:探讨钛合金板置入在颅骨缺损修复中的应用。方法:对12例颅骨缺损的患者先进行三维CT检查,设计个性化的钛合金板置入以修复颅骨缺损。结果:本组患者均愈合良好,无感染、钛板外露及头皮血运障碍,避免了再次手术。结论:应用钛合金板修复颅骨缺损,具有良好的生物学力度,抗击性强,并发症少,生物相容性好等优点,可获得较好的治疗效果。     

Evaluation of BioCorkscrew and Bioknotless RC suture anchor rotator cuff repair fixation: an in vitro biomechanical study

This in vitro biomechanical study used cadaveric specimens to compare the rotator cuff repair fixation provided by BioCorkscrew and Bioknotless RC suture anchors. Three cm wide by 1-cm long full-thickness supraspinatus defects were repaired using either two BioCorkscrew suture anchors with combined vertical and horizontal mattress sutures (n = 7) or three Bioknotless RC suture anchors with simple sutures (n = 7). Therefore, the BioCorkscrew suture anchor group had two sutures per anchor (four total sutures), while the Bioknotless RC suture anchor group had one suture per anchor (three total sutures). Two-phase cyclic (5–100 N, 1,000 cycles and 5–180 N, 2,000 cycles) and load to failure tests (31 mm/s) were performed. Non-parametric statistics were used to compare group differences (P < 0.05). All of the BioCorkscrew group specimens (seven of seven) completed the two phase cyclic test regimen without failure or gapping ≥ 5 mm, compared to only three of seven of the Bioknotless RC group (Fisher’s Exact test = 0.03). Groups did not differ for repair site gapping during the 5–100 N cyclic test phase (Fisher’s Exact test = 0.77), however more of the Bioknotless RC group displayed gapping ≥ 5 mm during the 5–180 N cyclic test phase than the BioCorkscrew group (P = 0.02). The BioCorkscrew group also displayed greater yield load during load to failure testing (492.2 ± 204 N vs. 296.4 ± 155 N, P = 0.03). In this in vitro biomechanical study, the BioCorkscrew group with combined vertical and horizontal mattress sutures displayed greater cyclic test survival, less repair site gapping, and superior yield load compared to the Bioknotless RC group with simple sutures. These results in human cadaveric rotator cuff-humerus specimens suggest better immediate post-operative repair site strength and a reduced need for post-operative restrictions. Clinical studies are needed to determine how these rotator cuff repair modes withstand the forces of early rehabilitation and activities of daily living that potentially influence patient outcomes.     

First clinical experiences with an implantable bone conduction hearing aid at the University of Amsterdam

Summary A transcutaneous bone-conduction hearing aid was implanted in 11 patients who were not suitable for transcranial sound amplification. Audiological and surgical selection criteria were followed strictly. One device had to be explanted and minor revision surgery was needed in two cases for skin irritation and scarring. In general the aids were well tolerated but the amplification power of the external device proved to be insufficient in some patients, in whom bone conduction levels were on the borderline of the selection limits. Correspondence to: W.A. Dreschler     

Progressive peri‐implantitis. Incidence and prediction of peri‐implant attachment loss.

The aim of this prospective study was to characterize an implant patient population exhibiting clinical signs of peri‐implantitis and to determine subsequently the incidence of progressive attachment loss. The predictive values of diagnostic parameters were evaluated. 25 patients with 54 endosseous implants that had been loaded for 41±15 months were included in the study. Clinical parameters included the assessment of plaque, bleeding on probing, probing depth, attachment levels, and Periotest® values. Probing measurements were performed in duplicate by means of a controlled force electronic probe (Periprobem). Peri‐implant crevicular fluid samples were collected and assayed for neutral proteolytic enzyme (NPE) activity (Periocheck®). Analysis of duplicate baseline probing data revealed a high degree of reproducibility (mean difference: 0.1±0.3mm). A minimum threshold of 1.0mm (>3×S.D.) loss of probing attachment was chosen to classify a site as positive for breakdown. Alternatively, the tolerance method was employed to identify sites with progressive attachment loss. After 6 months, irrespective of the analytical method, 6 percent of all sites (in 19% of the implants) and 28% of the patients had experienced further per attachment loss. There were significant differences ( p <0.05) in mean plaque (73% vs. 45%) and NPE (36% vs. 12%) scores between patients with progressive peri‐implantitis and those with stable peri‐implant conditions. Both bleeding on probing and the NPE‐test were characterized by high negative predictive values, and thus negative scores can serve as indicators for stable peri‐implant conditions. For monitoring peri‐implant health during recall visits, attachment level recordings with a controlled force electronic probe in conjunction with enzymatic diagnostic tests of the host response can be recommended.     

种植牙手术的导向模板定向法临床研究

本文介绍了用于人工牙根种植手术的一种导向模板定向法。该导向模板由圆柱形金属定向杆、导向钛管、负压成型的塑料牙列套及自凝塑料增强基托组成。临床应用35例.效果满意。