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1.
Anterior disk displacement of the temporomandibular joint   总被引:3,自引:0,他引:3  
Summary In order to examine the diagnostic significance of typical clinical symptoms in temporomandibular joint (TMJ) disorders for diagnosis of anterior disk displacement, clinical findings were compared with the degree of disk displacement in 84 TMJs of 59 patients with TMJ disorders, who were examined clinically and by means of magnetic resonance imaging (MRI). The control group consisted of 31 subjects with no TMJ symptoms. No significant correlation between the degree of anterior disk displacement and palpation pain of the masticatory muscles or clicking/crepitus of the TMJ could be found. Joint clicking was observed in 65% of patients with TMJ symptoms in normal disk position (NDP). The percentage of joint clicking was almost the same in patients with anterior disk displacement with reposition (ADWR) (68%). There were significant correlations between active mouth opening and disk position as well as between a history of pain and disk position. Patients with NDP and ADWR had almost identical mouth opening values: 48 (±5) mm and 46 (±5) mm respectively. In contrast to these groups the mean values decreased significantly to 42 (±6) mm in patients with anterior disk displacement without reposition (ADWOR). There were no significant correlations between occlusal findings (centric relation and habitual relation, early occlusal contacts, abrasion facets) and disk position when viewed either collectively or individually.
Anteriore Verlagerung des Discus articularis des Kiefergelenkes
Zusammenfassung Zur Überprüfung der Wertigkeit typisch klinischer Symptome für Funktionsstörungen zur Diagnose von Diskusverlagerungen wurden 84 Kiefergelenke von 59 Patienten mit Funktionsstörungen und 31 Kiefergelenke von klinisch asymptomatischen Probanden mittels Magnetresonanztomographie (MRT) untersucht und die einzelnen klinischen Befunde der Art der Diskusvergerung gegenübergestellt. Zwischen dem Grad der anterioren Diskusverlagerung und einem positiven Palpationsbefund der Kaumuskulatur, einem Palpationsschmerz der Kiefergelenke und dem Auftreten von Gelenkgeräuschen ergaben sich keine signifikanten Beziehungen. Bei funktionsgestörten Patienten zeigte sich mit 65% bei normaler Diskusposition (NDP) fast ebenso oft ein Gelenkknacken wie bei Patienten mit anteriorer Diskusverlagerung mit Reposition (VMR, 68%). Signifikante Beziehungen bestanden zwischen aktiver Mundöffnung und Diskusposition sowie anamnestisch angegebenen Schmerzen und Diskusposition. Während bei NDP- und VMR-Patienten mit 48 (±5) mm und 46 (±5) mm ähnlich hohe Mundöffnungswerte vorlagen, nahmen diese bei Patienten mit anteriorer Diskusverlagerung ohne Reposition (VOR) auf 42 (±6) mm signifikant ab. Okklusale Befunde (Differenz zwischen zentrischer und habitueller Okklusion >2 mm, vorzeitige okklusale Kontakte, Auftreten von Schliffacetten) zeigten in ihrer Gesamtheit wie auch in der Einzelbetrachtung keine signifikanten Beziehungen zur Diskusposition. Die Ergebnisse zeigen, daß für die Diagnostik von Funktionsstörungen allgemein als bedeutend anerkannte klinische Symptome in bezug auf die Art und das Vorliegen einer anterioren Diskusverlagerung allein keine sichere Aussage zulassen. Dies betrifft besonders die anteriore Diskusverlagerung ohne Reposition. Gleichzeitig wird die Zuverlässigkeit der MRT für die klinisch oft schwierige Diagnostik der Bestimmung der Diskusverlagerung bei Patienten mit Funktionsstörungen des Kausystems bestätigt.
  相似文献   
2.
颞下颌关节的功能状态关系到口腔颌面外科、正畸科和修复科等的治疗成败,超声作为颞下颌关节功能评价的一种新兴手段,以其无损伤性、经济、有效等特点得到了越来越广泛的应用。下面就超声在颞下颌关节盘位置检查、髁突运动轨迹和颞下颌关节音检测等方面的作用作一综述。  相似文献   
3.

Purpose

Tests on animals of different species with large differences in intervertebral disc size are commonly used to investigate the therapeutic efficacy of intravenously injected solutes in the disc. We hypothesize that disc size markedly affects outcome.

Methods

Here, using a small non-metabolized molecule, glucosamine (GL) as a model solute, we calculate the influence of disc size on transport of GL into rat, rabbit, dog and human discs for 10 h post intravenous-injection. We used transient finite element models and considered an identical GL supply for all animals.

Results

Huge effects of disc size on GL concentration profiles were found. Post-injection GL concentration in the rat disc reached 70 % blood concentration within 15 min but remained below 10 % in the human disc nucleus throughout. The GL rapidly penetrated post-injection into smaller discs resulting in homogeneous concentrations. In contrast, GL concentration, albeit at much lower levels, increased with time in the human disc with a small outward flux at the annulus periphery at longer periods.

Conclusions

Changes in the disc size hugely influenced GL concentrations throughout the disc at all regions and times. Increases in administered dose can neither remedy the very low concentration levels in the disc center in larger human disc at early post-injection hours nor alter the substantial differences in concentration profiles estimated among various species. The size effect will only be exacerbated as molecular weight of the solute increases and as the endplate calcifies. Extrapolation of findings from animal to human discs on the efficacy of intravenously administered solutes must proceed with great caution.  相似文献   
4.
We analyzed the clinical efficacy of the Zero-P implant (Synthes GmbH Switzerland, Oberdorf, Switzerland) in the treatment of single level cervical spondylotic myelopathy. The clinical data of 47 patients with single level cervical spondylotic myelopathy were retrospectively analyzed. Twenty-two patients were treated with a Zero-P implant (Group A) and 25 with a titanium plate with cage (Group B) between January 2009 and September 2010. Operative time, intraoperative blood loss, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores and JOA recovery rate, dysphagia incidence and adjacent segment degeneration rate were measured. The mean operative time in Group A and Group B was 98.18 minutes and 105.4 minutes, respectively. The average intraoperative blood loss in Group A and Group B was 87.95 ml and 92.4 ml, respectively. There were no statistical differences in operation time and intraoperative blood loss between the two groups (p > 0.05). The JOA score was significantly improved in the two groups (p < 0.001), and the recovery rate was similar (60.86% for Group A versus 62.95% for Group B, p > 0.05). Dysphagia was experienced by one (4.5%) patient in Group A and eight (32%) patients in Group B, which was significantly different (p = 0.044). There was no statistical significance found in the adjacent level degeneration rates between Group A and Group B (p = 0.330). The Zero-P implant and traditional titanium plate with cage are effective treatments for single level cervical spondylotic myelopathy, but the Zero-P implant has a lower dysphagia incidence.  相似文献   
5.

Purposes

Diabetes mellitus (DM) is thought to be an important aetiological factor in intervertebral disc degeneration. A glucose-mediated increase of oxidative stress is a major causative factor in development of diseases associated with DM. The aim of this study was to investigate the effect of high glucose on mitochondrial damage, oxidative stress and senescence of young annulus fibrosus (AF) cells.

Methods

AF cells were isolated from four-week-old young rats, cultured, and placed in either 10 % FBS (normal control) or 10 % FBS plus two different high glucose concentrations (0.1 M and 0.2 M) (experimental conditions) for one and three days. We identified and quantified the mitochondrial damage and reactive oxygen species (ROS) (oxidative stress). We also identified and quantified the occurrence of senescence and telomerase activity. Finally, the expressions of proteins were determined related to replicative senescence (p53-p21-pRB) and stress-induced senescence (p16-pRB).

Results

Two high glucoses enhanced the mitochondrial damage in young rat AF cells, which resulted in an excessive generation of ROS in a dose- and time-dependent manner for one and three days compared to normal control. Two high glucose concentrations increased the occurrence of senescence of young AF cells in a dose- and time-dependent manner. Telomerase activity declined in a dose- and time-dependent manner. Both high glucose treatments increased the expressions of p16 and pRB proteins in young rat AF cells for one and three days. However, compared to normal control, the expressions of p53 and p21 proteins were decreased in young rat AF cells treated with both high glucoses for one and three days.

Conclusions

The present study demonstrated that high glucose-induced oxidative stress accelerates premature stress-induced senescence in young rat AF cells in a dose- and time-dependent manner rather than replicative senescence. These results suggest that prevention of excessive generation of oxidative stress by strict blood glucose control could be important to prevent or to delay premature intervertebral disc degeneration in young patients with DM.  相似文献   
6.
目的:探讨非洲人LDH(Lumbar Disc Herniated)术后复发的原因及再次治疗的最佳方法。方法:采用骶管硬膜外前间隙介入注射利得合剂(A组)和休息+口服消炎镇痛药物(B组)治疗LDH术后复发,运用统计学分析,并进行对比研究,根据Prolo腰椎术后评定标准,对全都复发病例(56例)进行了3~9个月的随访。结果:A组30例中,8~10分11例,6~7分15例,〈5分4例;B组26例中,8~10分6例,6~7分12例,〈5分8例。两组结果经统计学比较差别有显著性(P〈0.05)。结论:非洲人LDH术后复发的原因也是多方面的,骶管硬膜外前间隙介入注射利得合荆也是一种行之有效的治疗方法。  相似文献   
7.
我们对门诊就诊52例腰腿痛病人,男30人,女22人,随机分为三组进行了对比观察。患者分组1(超短波组)、组2(Xenon氙光低周波治疗组)和组3(氙光低周波加椎旁或硬膜外腔封闭组)。对于上述各组以VisualAnalogScale(VAS)测痛法以疼痛为主要指标、快适度以舒适轻松程度为主要指标,就治疗前后自觉症状的改变进行了评价及统计学处理。结果表明:组3优于组2,组2优于组1,都具有显著性差异。本组结果提示日本医广公司生产的550/型氙光低周波治疗仪加激素类药物行椎旁或硬膜外腔封闭具有良好的协同作用,治疗效果显著。使VAS痛苦度明显降低,同时治疗后还具有良好的舒适感,是治疗腰腿痛的好方法。  相似文献   
8.
目的研究胸腰椎骨折经椎弓根植骨术后伤椎愈合的方式及影响因素。方法本次研究纳入自2011-01-2013-01诊治的74例具有完整随访结果的患者,采用经椎弓根植骨36例,同期未经椎弓根植骨38例。依据脊柱骨折负荷分享分级、笔者设计的椎体轴位9分区法明确骨折损伤程度、骨折复位及伤椎植骨情况、骨折愈合及伤椎植骨愈合情况。结果术后随访16~24个月,平均20个月。未植骨组:术后1年随访时椎体内各区形成空洞总计21.1%。植骨组:术后1年随访时椎体内各区形成空洞总计24.1%。结论胸腰椎骨折后伤椎经椎弓根植骨术中可撬拨复位塌陷及碎裂的上终板,减少髓核组织的突入发生,形成椎体内有效的可填充空腔,便于椎体内充分植骨,形成利于骨细胞爬行替代的框架结构,减少晚期上终板的塌陷及椎体内空洞的形成。  相似文献   
9.

Background

Pediatric foreign-body ingestions are commonly managed by emergency physicians. Risk assessment and specific intervention are dependent on the nature and location of the foreign body. Radiographic evaluation is usually necessary to help define the clinical situation.

Case Report

We present an interesting case of presumed ingestion of several disk batteries by a toddler with an unexpected outcome, reviewing aspects of this clinical problem and highlighting potential pitfalls in medical decision making.

Why Should an Emergency Physician Be Aware of This?

Pediatric foreign-body ingestions are commonly managed in the emergency department, and timely and accurate intervention is dependent on correct defining and localization of the foreign body. This case illustrates potential pitfalls in this evaluation.  相似文献   
10.
PurposeTo evaluate the dynamic range of retinal nerve fiber layer (RNFL) and optic nerve head (ONH) parameters measured using optical coherence tomography (OCT) in conditions ranging from nonglaucomatous status to advanced glaucoma by longitudinal observation.MethodsA total of 15 eyes from 12 participants with glaucoma progression from a nonglaucomatous status to advanced glaucoma were included. The RNFL and ONH parameters were compared between the nonglaucomatous and advanced stages within the same eye. The absolute and relative changes in OCT parameters were analyzed.ResultsThe median highest intraocular pressure was 42.5 mmHg (interquartile range, 37.5 to 54.5 mmHg), and the final mean deviation of the visual field test was −24.68 dB (interquartile range, −23.93 to −31.13 dB). The median relative changes in RNFL thickness were −40.6% in the overall area, and −51.9%, −21.4%, −51.1%, and −41.8% in the superior, nasal, inferior, and temporal quadrants, respectively (all p < 0.05). Relative changes in the rim area, disc area, average cup to disc ratio, vertical cup to disc ratio, and cup volume were −56.64%, 0.59%, 62.10%, 66.0%, and 337.90%, respectively (all p < 0.05, except for disc area with a p-value of 0.753).ConclusionsThe dynamic range of the RNFL thickness ranged from 40.6% to 51.9%, and the dynamic range of the ONH parameters ranged from 56.64% to 337.90%. During the course of glaucoma progression, the cup volume showed the widest dynamic range. However, the disc area did not show significant changes.  相似文献   
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