颧上颌复合体骨折的诊断与治疗

颧上颌复合体是面部最突出的部位之一,由于其解剖部位的特殊性,颧上颌复合体骨折在面中部骨折中占有相当大的比例。骨折后不仅引起局部凹陷畸形,甚至导致开口受限、复视等功能障碍。作者结合文献复习和临床经验,对颧上颌复合体骨折的原因、临床表现、治疗方法、手术入路和术后并发症等进行了讨论。认为眉侧切口联合口内切口入路,可以避免冠状切口的种种弊端。此法可在直视下开放复位,较好地暴露颧骨、上颌骨连接处及眶下区骨折,切断颧骨咬肌附丽,松解颧骨骨折块,再进行内固定,效果良好。手术后瘢痕小,面神经功能无损伤,外形及功能恢复良好,值得推广。     

24例髁突骨折经下颌后进路行坚强内固定的疗效观察

目的:介绍发生于髁突颈和髁颈以下髁突骨折用小型钛板经下颌后进路行解剖复位、坚强内固定术的方法和经验。方法:发生于髁突颈和髁颈以下骨折24例30侧,经下颌后进路以小型钛板行坚强内固定术。术后3～6个月后复查并评价疗效,复查内容包括:张口度、张口型、咬合关系、X线表现、面神经损伤情况。结果:张口度较术前明显增大,张口型偏移明显改善,错牙合3例,面神经下颌缘支损伤2例。X线检查:髁突骨折复位良好,髁突无移位。结论:下颌后进路是一种治疗髁突颈和髁颈以下骨折的有效方法。     

Open mandibular condylotomy (osteotomy) with precision scaphoid staple osteosynthesis and meniscopexy. A description of the operation

The technical minutiae of the operation of open mandibular condylotomy and precision scaphoid staple osteosynthesis with meniscoplasty or meniscopexy is described and illustrated. The operation is regarded as an evolution of closed condylotomy described by Ward in 1961 and is indicated for those cases of severe and persistent temporomandibular joint pain and crepitus unresponsive to skilled conservative treatment over a reasonable time. The success of the procedure is probably the sequel of a partial denervation of the joint capsule associated with arthrotomy, the interruption of venous hypertension, the relocation of the mandibular condyle and enlargement of the joint space. The operation is also applicable to cases of active (and inactive) mandibular condylar hyperplasia wherein a condylar neck ostectomy and staple is used to ablate an active growth centre or correct a lesser degree of mandibular asymmetry.     

TMJ symptoms reduce chewing amplitude and velocity,and increase variability

Objective: The null hypothesis was that mandibular amplitude, velocity, and variability during gum chewing are not altered in subjects with temporomandibular joint (TMJ) internal derangements (ID).

Methods: Thirty symptomatic subjects with confirmed ID consented to chew gum on their left and right sides while being tracked by an incisor-point jaw tracker. A gender and age matched control group (p > 0.67) volunteered to be likewise recorded. Student’s t-test compared the ID group’s mean values to the control group.

Results: The control group opened wider (p < 0.05) and chewed faster (p < 0.05) than the ID group. The mean cycle time of the ID group (0.929 s) was longer than the control group (0.751 s; p < 0.05) and more variable (p < 0.05).

Discussion: The ID group exhibited reduced amplitude and velocity but increased variability during chewing. The null hypothesis was rejected. Further study of adaptation to ID by patients should be pursued.     

冠状切口在颧骨复合体骨折中的应用

目的探讨颧骨复合体骨折复位和固定术中应用冠状切口入路的手术适应证、手术方法及减少并发症的措施。方法84例颧骨复合体骨折的患者应用单纯冠状切口为36.9%、冠状切口 下睑缘切口为32.1%、冠状切口 下睑缘切口 前庭沟切口为16.7%和冠状切口 前庭沟切口为14.3%。术中患者均使用微型钛板或小型钛板坚强内固定。对于眶底骨折出现眼球内陷的患者以羟基磷灰石人工骨进行眶底重建。结果84例患者均未发生手术后切口感染,术后随访3个月到2年,无面神经永久性损伤,术后所有咬合关系紊乱的患者均达到功能性咬合。通过训练后张口度得到满意恢复。8例患者术后患侧颧弓处仍稍显膨隆。术后眼球内陷只有1例仍大于3mm,其余均恢复满意。结论颧骨复合体骨折使用头皮冠状切口时,熟练掌握颞部的解剖层次是至关重要的,仔细保护神经及血管结构可减少手术并发症。     

Clinical study of the internal gaps of zirconia and metal frameworks for fixed partial dentures

The aim of this clinical study was to compare the internal gaps between abutment teeth and posterior fixed partial dentures (FPDs) fabricated utilizing milled zirconia and cast gold-alloy frameworks. As part of an ongoing randomized controlled clinical trial, 32 three-unit FPDs (16 zirconia and 16 metal-ceramic) in 25 patients were randomly selected for adaptation measurements. During the bisque-stage ceramic try-in, an A-silicone impression material was placed between the abutment teeth and the framework. The internal gap, corresponding to the thickness of the replica, was measured under magnification at the following locations: cervical, axial, and occlusal (cusp-tips and central). The internal gaps of FPDs with zirconia frameworks were significantly larger in cervical, axial, and centro-occlusal regions (cervical: 189.6 ± 71.8  μ m vs. 118.6 ± 31.5  μ m; axial: 140.5 ± 38.3  μ m vs. 95.7 ± 18.1  μ m; and centro-occlusal: 192.0 ± 66.5  μ m vs. 153.1 ± 69.8  μ m). The cervical gaps next to the pontics were significantly larger compared with those of the outer walls in both types of FPDs (zirconia: mean difference 67.7 ± 114.7  μ m; metal-ceramic: mean difference 30.0 ± 71.2  μ m). Posterior three-unit FPDs incorporating milled zirconia frameworks exhibited larger internal gaps than those constructed using conventional metal-ceramic techniques.     

下颌骨延长术后牵张器拆除时机的实验研究

目的 :研究家兔下颌骨延长术后新生骨回缩情况 ,确定牵张器的拆除时机。方法 :成年家兔 16只 ,体重 2 .4～ 2 .6kg ,随机等分为 4组 ,每组 4只 ;行双侧下颌骨骨切开术 ,采用内置式牵张器对双侧下颌骨同时进行牵引。延迟期 :7d ;牵张期 :10d ;牵引速率 0 .5mm/次 ,2次 /d ;保持期分别为 2周、4周、8周、12周。保持期后行第二次手术取出牵张器 ,并同时植入钛钉为参照 ,判断下颌骨改建后新成骨有无缩短 ,观察期为 8周。结果 :保持期为 2周、4周组的实验动物新生骨在 8周后明显回缩 ,分别为 2 .1± 1.2mm、1.4± 1.3mm ;而保持期 8周、12周组 ,8周后新生骨未见明显回缩。结论 :兔下颌骨牵张延长术后 ,牵张器应在保持期 8周拆除 ;拆除过早 ,新生骨区产生明显回缩。     

Evaluation of internal adaptation in ceramic and composite resin inlays by silicon replica technique

This study was aimed at investigating the internal adaptation of a ceramic (Ceramco II) and two composite resin inlay materials (SureFil and 3M Filtek Z 250) using silicon replica technique as an indicator. Forty-five standard mesial-occlusal-distal (MOD) cavities were prepared into brass moulds by using computer numerically controlled system. Inlays were prepared according to manufacturers' instructions with indirect methods. Replicas of the prepared cavities and inlays were produced with a polyvinyl siloxane material (Elite H-D). The spaces between inlays and cavities were filled by different coloured light-body polyvinyl siloxane material. Two parallel slices (mesio-distally) were obtained from the replicas with a sharp blade. Different coloured polyvinyl siloxane material thickness between cavity and inlay was measured at seven points (mesial, occlusal and distal). The data were evaluated with anova and Tukey's honestly significantly different (HSD) statistical tests. In the SureFil and Ceramco II groups, the sizes of the contraction gaps at mesial and distal gingival floors were greater than that of the occlusal marginal walls. In comparison of gap formation at occlusal regions, while the 3M composite group showed highest gap values (204.33 +/- 75.45 microm), the Ceramco II group revealed the lowest (141.17 +/- 23.66 microm) (P < 0.05). At the gingival floors, gap formation of Ceramco II group was the highest (227.08 +/- 51.95 microm). Neither the 3M Filtek Z250 nor SureFil group showed any statistical difference between gap values of their self-occlusal and gingival floors (P > 0.05). In conclusion, our results showed that ceramic inlays did not confer any big advantage for internal adaptation over the composite inlays.     

Differential localization of laminin gamma and integrin beta in primary cultures of the rat gingival epithelium

OBJECTIVES: The aim of this study was to investigate the differential immunolocalization of laminin gamma(2) and integrin beta(4) in primary cultures of the rat gingival epithelium. METHODS: The gingival epithelium was obtained from Sprague-Dawley rats and was cultured in serum-free keratinocyte growth medium (DK-SFM). Western blotting analysis, immunofluorescence, confocal laser scanning microscopy (CLSM), and immuno-gold labeling for laminin gamma(2) and integrin beta(4) were employed. CLSM images for laminin and integrin were analyzed in horizontal (x-y axis) and in vertical (x-z axis) sections. RESULTS: Both laminin gamma(2) and integrin beta(4) were detected by Western blot analysis in the gingival epithelium. Immunolocalization of laminin gamma(2) was distinct in the cytoplasm to form one or two irregular rings in gingival epithelial cells. By contrast, integrin beta(4) was localized diffusely in the cytoplasm. F-actin (indicating actin filaments) was clearly discernible at the periphery of the cytoplasm to form a cellular fringe. In x-z axis images obtained by CLSM, laminin gamma(2) was recognized as large foci in the most inner portion just above the basal plasma membrane. Integrin beta(4) existed in the area where F-actin was labeled surrounding the membrane. Immuno-electron microscopy showed that 10nm colloidal gold particles indicating laminin gamma(2) were mainly localized at the extracellular portion and in the peripheral cytoplasm, whereas integrin beta(4) was distributed in the cytoplasm close to the basal plasma membrane but not in extracellular regions. CONCLUSIONS: In primary cultures of the rat gingival epithelium, both laminin gamma(2) and integrin beta(4) may be produced by the epithelium, and irregular rings of laminin gamma(2) are formed in areas where gingival cells adhere to the extracellular matrix.