Three-dimensional soft tissue prediction in orthognathic surgery: a clinical comparison of Dolphin,ProPlan CMF,and probabilistic finite element modelling

Three-dimensional surgical planning is used widely in orthognathic surgery. Although numerous computer programs exist, the accuracy of soft tissue prediction remains uncertain. The purpose of this study was to compare the prediction accuracy of Dolphin, ProPlan CMF, and a probabilistic finite element method (PFEM). Seven patients (mean age 18 years; five female) who had undergone Le Fort I osteotomy with preoperative and 1-year postoperative cone beam computed tomography (CBCT) were included. The three programs were used for soft tissue prediction using planned and postoperative maxillary position, and these were compared to postoperative CBCT. Accurate predictions were obtained with each program, indicated by root mean square distances: RMS_Dolphin = 1.8 ± 0.8 mm, RMS_ProPlan = 1.2 ± 0.4 mm, and RMS_PFEM = 1.3 ± 0.4 mm. Dolphin utilizes a landmark-based algorithm allowing for patient-specific bone-to-soft tissue ratios, which works well for cephalometric radiographs but has limited three-dimensional accuracy, whilst ProPlan and PFEM provide better three-dimensional predictions with continuous displacements. Patient or population-specific material properties can be defined in PFEM, while no soft tissue parameters are adjustable in ProPlan. Important clinical considerations are the topological differences between predictions due to the three algorithms, the non-negligible influence of the mismatch between planned and postoperative maxillary position, and the learning curve associated with sophisticated programs like PFEM.     

围产期PFOS暴露对幼鼠海马BDNF/TrkB/CREB信号通路影响

目的 探讨观察母孕鼠围产期全氟辛烷磺酸盐(perfluorooctane sulphonate,PFOS)暴露对幼鼠海马组织BDNF/TrkB/CREB信号通路关键基因表达的影响。 方法 20只昆明种雌性小鼠随机分为对照组和低、中、高剂量组,从孕鼠怀孕第2 d开始(gestation day2, GD2)到幼鼠出生后21 d(postnatal day21,PND21)分别给予低、中、高剂量组孕鼠PFOS剂量为 0.1、1.0、5.0 mg/(kg·bw)灌胃染毒,对照组给予等体积的0.05% Tween-20水溶液。灌胃量为0.1 ml/10 (g·bw)。PND 21 d处死幼鼠,收集脑组织,分离海马及皮层。HE染色观察脑组织常规病理改变,实时荧光定量PCR(Quantitative Real-time PCR,QPCR)检测海马组织中BDNF、TrkB、CREB、Syn1及Syp的mRNA表达水平。 结果 与对照组相比较,低、中、高三个剂量组对幼鼠的死亡率和体质量的影响差异无统计学意义(P>0.05)。但是在高剂量组幼鼠海马组织出现空泡,海马BDNF、TrkB、CREB mRNA水平显著降低,分别由对照组的(0.98±0.11)、(1.03±0.09)、(1.08±0.12)下降到(0.22±0.21)、(0.71±0.14)、(0.37±0.26),并在中、高剂量组引起了幼鼠突触相关蛋白Syn1和Spy的mRNA水平显著降低,分别由对照组的(1.10±0.09)、(0.97±0.08)下降到中剂量的(0.41±0.23)、(0.71±0.17)和高剂量的(0.39±0.19)、(0.63±0.19),差异均有统计学意义(P<0.05)。 结论 PFOS损伤海马BDNF/TrkB/CREB信号通路可能是PFOS神经发育毒性之一。     

Agminated fibroblastic connective tissue nevus in a 1‐year‐old boy

Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy.     

A review of suture anchors

Suture anchors are designed to allow soft tissue to bone healing in cases where inadequate soft tissue stock on bone makes it impossible to perform a direct soft tissue-to-soft tissue repair. Suture anchor fixation is one of the most important innovations in arthroscopic glenohumeral shoulder surgery, optimizing the link between bone and soft tissue at the rotator cuff footprint. Newer developments and techniques have expanded the use of suture anchors to most other musculoskeletal tissues including the hip, elbow, hand, knee foot and ankle.Their success depends on having an understanding of the biology and biomechanics that affect their use and knowing the factors that may affect the clinical outcome. This review concentrates on the design, insertion technique, composition and evolution of suture anchors in orthopaedic surgery and the ways in which they are utilised in different tissues.     

Neurosensory issues after lateralisation of the inferior alveolar nerve and simultaneous placement of osseointegrated implants

Our aim was to evaluate neurosensory symptoms after lateralisation of the inferior alveolar nerve (IAN). We studied a retrospective case series with one-year follow up that included 139 procedures in 123 patients. After the IAN had been located it was deflected from the mandibular body and the implant placed. Sensitivity was mapped 24 hours, one month, six months, and one year after the intervention by gently pressing the skin and lips with the tip of a probe. A total of 337 implants were placed in 123 patients aged between 44 and 68 years.There were 33 men and 90 women and they all recovered. The IAN was mobilised by one of two procedures, one that involves the nerve directly (transposition) and one that does not (lateralisation). During lateralisation the nerve is deflected laterally through a mandibular osteotomy, while the mental nerve and mental foramen are not manipulated. The resulting hypoaesthetic area was drawn on a graph to assess its extension. Although different techniques are available for placing implants in atrophic jaws, mobilisation of the IAN is indicated in certain cases in which other techniques are not feasible or have a high risk of complications.     

超声造影增强模式鉴别软组织肿块良恶性

Objective: To investigate the ability of contrast enhancement patterns of contrast-enhanced ultrasound in differentiating benign and malignant soft tissue tumours.