The Influence of Different Traction Hooks on Tooth Movement During Distalization of the Lower Dentition: A Finite Element Analysis / 医用生物力学

Objective To study stress distributions of lower dentition distally moved with miniscrews in external oblique line area when the traction hooks with different lengths were placed at different positions by the three-dimensional (3D) finite element method. Methods Based on cone beam computed tomography (CBCT) data from a patient, traction hooks with the heights of 2 mm and 7 mm were constructed and fixed between the lateral incisors and the canine brackets, as well as between the canines and the first premolar brackets. Four kinds of 3D finite element models of full dentition distally moved with miniscrews were constructed. The 3 N traction force was loaded between the traction hook and the miniscrews. The maximum von Mises stress and initial displacement of the mandibular teeth and dentition under four working conditions were analyzed. ResultsWhen the traction hook with 7 mm-height was placed between the lateral incisor and the canine, the lower central incisor rotated clockwisely, with the crown moving labially and the root moving lingually. But under the other three working conditions, the central incisor rotated counterclockwisely, and the crown and root moved lingually. When the traction hook with 7 mm-height was placed between the canine and the first premolar, the lower canine crown moved proximally. But under the other three working conditions, both the crown and root moved distally. Under four working conditions, the mandibular molars all rotated counterclockwisely,with the crown and root moving distally. Conclusions Through 3D finite element analysis, biomechanical mechanism of the effect of different traction hooks on mandibular tooth movement during distalization of the lower dentition was elucidated.With full understanding of the biomechanical mechanism, proper selection for length and placement of the traction hook can achieve distal movement of the entire mandibular dentition more efficiently.

Idiopathic gingival fibromatosis: a case report and literature review / 口腔疾病防治

Objective @#To explore the etiology, clinical manifestations, diagnosis, differential diagnosis and treatment of idiopathic gingival fibromatosis, and to provide references for clinical diagnosis and treatment.@*Methods @#The clinical data and related literatures of a case of idiopathicgingival fibroma that occurred in the oral cavity were retrospectively analyzed. @*Results @#Total periodontal treatment was performed for the patient, and the gingival morphology was improved after periodontal surgery in the anterior region. Idiopathic gingival fibromatosis is a rare disease characterized by gingival tissue hyperplasia. The etiology and pathogenesis are unknown. The disease can occur in young children. Generally, it occurs after the permanent teeth erupt, and it manifests as extensive gingival hyperplasia, which can affect the entire gingival margin, gingival papilla and attached gingival, and can even reach the membrane-gingival junction. The pathological changes include thickening of the spinous layer of the gingival epithelium, significant increases in the epithelial styloid process, increases in the connective tissue volume, and filling with large collagen fiber bundles and a large number of fibroblasts. The blood vessels are relatively small, and inflammation is not obvious. Clinically, this disease needs to be distinguished from drug-induced gingival hyperplasia and chronic gingivitis with hyperplasia as the main manifestation. At present, the treatment of idiopathic gingival fibromatosis is mainly gingival angioplasty. The disease easily relapses after surgery. The recurrence rate is related to the quality of oral hygiene. After recurrence, it can be treated again.@*Conclusion@# Idiopathic gingival fibromatosis is relatively rare, and the diagnosis mainly depends on the history of inquiry, clinical manifestations and pathological examination. The treatment is mainly surgical resection, and future research should focus on finding a more effective treatment.

Consideraciones Anatomo-Quirúrgicas del Ligamento Reflejo / Reflected Ligament: Anatomical and Surgical Considerations

La anatomía de la región inguinal está bien descrita y detallada en la literatura, pero existen algunas controversias vinculadas al ligamento reflejo y a su inserción medial. El objetivo fue analizar la inserción del ligamento inguinal reflejo del músculo oblicuo externo en la línea alba, mediante lo observado en disecciones cadavéricas. Se utilizaron 30 cadáveres formolizados, en los que el ligamento reflejo fue disecado hasta su inserción en la línea alba. Se encontró la presencia del ligamento inguinal reflejo en 25 (83,33%) casos, 16 (64%) hombres y 9 (36%) mujeres, de los cuales sólo en 2 (8%) casos se observó la inserción interdigitada del ligamento inguinal reflejo con el contralateral; y en 5 (16,67%) casos (3 mujeres y 2 hombres), se constató ausencia del mencionado ligamento. El ligamento reflejo fue identificado en la mayoría de nuestros ejemplares. Este ligamento contribuye a la formación de la pared posteromedial del anillo inguinal superficial, siendo importante la necesidad de su conocimiento anatómico para su aplicación en la reparación quirúrgica de hernias inguinales con colocación protésica por vía anterior.

Anatomy of the inguinal region is well described in literature, but there is lack of information related to the reflected ligament and a dichotomy regarding its medial insertion. The aim was to carry out an observational analysis, through dissections, of the insertion of the reflected ligament of the external oblique muscle at the linea alba. We used 30 formolized corpses were, on which the reflected ligament was dissected to its insertion into the linea alba. Of the 30 bodies, we found the reflected ligament in 25 (83.33%), being 16 male (64%) and 9 females (36%), but only in 2 of them (8%) its insertion interdigitated with the contralateral. In 5 (16.67%) cases, 3 female (60%) and 2 male (40%), the absence of that ligament was found. The reflected ligament was identified in most of our specimens. Being part of the posterior limit of the superficial inguinal ring, its anatomical knowledge is important for the surgical repair of inguinal hernias with prosthetic placement, using anterior access.

Abdominal muscle electrical activity during labor expulsive stage: a cross-sectional study / Atividade elétrica muscular abdominal durante os esforços expulsivos do parto: um estudo transversal

BACKGROUND: During the second stage of labor, the progression of the fetal expulsion depends on many factors related to maternal and fetal parameters, including the voluntary abdominal pushing. OBJECTIVES: This study aimed to correlate the maternal and fetal parameters that may influence the voluntary maternal pushes during the second stage of labor by using surface electromyography. METHODS: The electromyographic activity of the rectus abdominis and external oblique muscles were measured during the second stage of labor in 24 Brazilian pregnant women. The diastasis of the rectus abdominis, the body mass index and the uterine fundal height were analyzed as maternal parameters and the fetal weight, cephalic circumference, APGAR scores and arterial pH and CO2 were analyzed as fetal parameters. The oxytocin usage and the expulsive phase duration were considered. RESULTS: A negative correlation between the rectus abdominis diastasis and the rectus abdomini muscle electromyographic parameters was found (r=-0.407 p=0.04). No statistically significant correlations were found among the rectus abdominis and external oblique muscles electromyography and the other maternal or fetal parameters, as well as among expulsive phase duration and the oxytocin usage. CONCLUSIONS: This study suggests that the rectus abdominis diastasis may be an influential parameter in generating voluntary pushes during the second stage of labor, however it cannot be considered the only necessary parameter for a successful labor.

CONTEXTUALIZAÇÃO: Durante o segundo estágio do parto, a progressão da expulsão fetal depende de vários fatores ligados a parâmetros maternos e fetais, dentre eles, o esforço abdominal voluntário. OBJETIVOS: Correlacionar os parâmetros maternos e fetais que podem influenciar os esforços voluntários durante a fase do segundo estágio do parto por meio da eletromiografia de superfície. MÉTODOS: As atividades eletromiográficas dos músculos retoabdominal e oblíquo externo foram medidas durante o segundo estágio do parto em 24 gestantes. A diástase do músculo retoabdominal, o índice de massa corpórea e a altura de fundo de útero foram analisados como parâmetros maternos, e o peso fetal, o perímetro cefálico, os índices de Apgar e o pH e pCO2 arterial foram analisados como parâmetros fetais. O uso de ocitocina e o tempo do período expulsivo foram considerados. RESULTADOS: Encontrou-se uma correlação negativa entre a diástase umbilical e os parâmetros eletromiográficos do músculo retoabdominal (p=0,04; r=-0,407). Não se encontrou correlação significativa entre a eletromiografia dos músculos retoabdominal e oblíquo externo e os demais parâmetros maternos e fetais, bem como entre o tempo do período expulsivo e o uso da ocitocina. CONCLUSÕES: O presente estudo sugere que a diástase umbilical pode ser um parâmetro influente na geração de esforços voluntários durante o período expulsivo do parto, porém não deve ser considerada de forma isolada para o sucesso do andamento do trabalho de parto.

Experience of Reconstruction of an Extensive Chest Wall Defect with Extended External Oblique Musculocutaneous Flap

PURPOSE: The resection of locally advanced or recurred breast cancers frequently result in large chest wall defects and it leads to a great challenges to cover. Generally simple skin grafts are not a practical option for patients because of their poor cosmetic appearance and prognosis. The latissimus dorsi and rectus abdominis musculocutaneous flap have traditionally been recommended for closure of these large defects. Though the cosmetic result of reconstruction using these flaps is often excellent, but has significant drawbacks. Therefore, we thought that chest wall reconstruction using the external oblique musculocutaneous flap can be an alternative method for extensive chest wall defect related to large, locally advanced breast carcinoma. METHODS & RESULTS: We present a case of a 50-year-old Korean female, refered to our department with a left breast tumor for 10 months. CT demonstrate a large tumor on the left anterior chest wall and multiple nodules of varying size in the cervical areas and liver. FDG-PET showed areas of hot uptake throughout the left chest wall, mediastinum and liver. Biopsy was consistent with invasive ductal carcinoma (Grade III). The initial tumor was considered inoperable, so a series of chemotherapy was initiated. Though the size of the breast mass was slightly decreased, the patient continued to suffer from purulent discharge, unpleasant odor and contact bleeding of the mass, the salvage mastectomy was performed. CONCLUSION: We could reconstruct 23x16cm sized large chest wall defect, resulting from the resection of a locally advanced breast carcinoma, using an external oblique musculocutaneous flap successfully. Immediate postoperatively checked flap was healthy. Overall result was good without any significant complications and discharged 3 weeks after operation.

Chest Wall Reconstruction with Thoracoabdominal Flap for Large Skin Defects after Mastectomy of Advanced Breast Cancer

PURPOSE: Radical surgical extirpation in advanced breast cancer patients produces extensive loss of skin with large defects requiring plastic surgical procedures for the closure. Many reconstructive methods exist, the choice of which depends upon the characteristic of the wound, extent of resection and patient comorbidities. For adequate coverage of the large skin defects following resection of advanced breast cancer, current authors have performed a thoracoabdominal flap. METHODS: From August 2008 to June 2009, 4 cases of thoraco-abdominal flap were performed for chest wall reconstruction after mastectomy of advanced breast cancer. Flap dissection was entirely performed in a subfascial plane and the flap involving the external oblique abdominal muscle. The flap was rotated clockwise in left chest wall defects and counterclockwise in right chest defects and the donor site was closed directly. RESULTS: Their mean age, 55.7 years and the average follow-up interval was 9 months. Patients' oncologic status ranged from stage IIIc to stage IV, it was classified according to the TNM staging system. Flap dimensions ranged between 15 x 15 and 25 x 25 cm. One flap sustained a partial loss at the distal margin and revision with pectoralis major musculocutaneous island flap. CONCLUSION: Large chest wall reconstructions are usually required after radical excision of advanced cancer stages patients with poor general conditions. Thoracoabdominal flap is a simple, quick single-stage procedure, and offer to patient fast recovery, low complication rate, enabling further concomitant adjuvant therapy.

Effects of Strengthening Internal and External Abdominal Oblique Muscles on Sitting Balance in Stroke Patients with Hemiplegia / 中国康复理论与实践

@#ObjectiveTo investigate the effects of strengthening internal and external abdominal oblique muscles on sitting balance in stroke patients with hemiplegia. Methods60 cases of patients with hemiplegia were randomly divided into treatment group and control group, 30 cases in each group. Control group patients were treated with conventional treatment. Internal and external abdominal oblique muscles training were accepted in treatment group in addition. Before and 1 month after treatment, all the patients were assessed with Fugl-Meyer Assessment of balance function and muscle strength. ResultsAfter treatment, the Fugl-Meyer assessment scores of balance, muscle strength were significantly higher in the treatment group than in the control group（P＜0.01）. ConclusionMuscle strengthen training in internal and external abdominal oblique muscles will promote sitting balance in hemiplegic patients.

External Oblique Myocutaneous Flap for Reconstruction of Large Chest-Wall Defects following Resection of Advanced Breast Cancer

PURPOSE: Major chest wall reconstruction following radical excision of advanced breast cancer is remained a challenging treatment of oncoplastic surgeons. The aims of this study are to introduce a method of external oblique myocutaneous flap (EOMCF) and evaluate the effect of large chest wall reconstruction using external oblique myocutaneous flap. METHODS: A retrospective review of 17 patients who underwent chest wall reconstruction with external oblique myocutaneous flap from January of 2007 through May of 2008 was performed. The upper edge of external oblique myocutaneous flap was lower margin of defect. The medial edge was mid-line of abdomen by umbilicus, vertically along the linea alba. The lower edge was a lateral transverse line at the level of umbilicus. The flap was rotated clockwise in the left side chest wall defects and counterclockwise in the right. RESULTS: The mean chest wall defect was 360.8+/-137.8 cm2 and the mean flap size was 591.1+/-136.2 cm2. The mean reconstruction time was 41.5+/-7.9 min and patients were discharged on 8.8+/-1.2 postoperative day (mean). Three patients had superficial skin loss (<5%) and this lesions are healed with conservative therapy. CONCLUSION: We propose that the external oblique myocutaneous flap may be a safe and feasible method for reconstruction of large chest wall defects after radical mastectomy including all breast skin.

Cadaver as an experimental model to study the effect of muscle advancement on the waistline

The use of cadaver as an experimental model to evaluate the waistline after correction of rectus diastasis and the advancement of the external oblique muscles in cadavers were described on this article. Two parameters were used: the measurement of the abdominal circumference and the overlap of the two skin flaps formed by a xypho-pubic incision. With a previously marked area of undermining of the aponeurotic layer, measurements of the overlapped flaps were made in the following stages of dissection: 1) with the myo-aponeurotic layer intact; 2) after the correction of rectus diastasis; and 3) after the advancement of the external oblique muscle. The experimental model described showed to be feasible to demonstrate the effects of the correction of rectus diastasis and of the advancement of external oblique muscles on the waistline.

O uso de cadáver como modelo experimental para avaliar a cintura após a correção da diástase de retos e o avanço dos músculos oblíquo externos é descrito neste estudo. Dois parâmetros foram utilizados: a medida da circunferência abdominal e a sobreposição de dois retalhos dermogordurosos formados por uma incisão xifo-púbica. Após a definição da área de descolamento supra-aponeurótico, a medida da sobreposição dos retalhos foi realizada nas seguintes fases de dissecção: 1) com o plano mio-aponeurótico íntegro; 2) após a correção da diástase de retos; e 3) após o avanço dos músculos oblíquos externos. O modelo experimental descrito mostrou-se viável para demonstrar os efeitos da correção da diástase de retos e no avanço dos músculos oblíquo externos na cintura.

Cadaver as an experimental model to study abdominal wall tension

The use of cadaver as an experimental model to evaluate tension of the abdominal wall after aponeurotic incisions and muscular undermining is described on this article. The tension required to pull the anterior and the posterior rectus sheaths towards the midline was studied in fresh cadavers at two levels: 3 cm above and 2 cm below the umbilicus. Traction measurement was assessed with a dynamometer attached to suture loops on the anterior and posterior recti sheaths, close to the midline, above and below the umbilicus. The quotient of the force used to mobilize the aponeurotic site to the midline and its resulting displacement was called the traction index. These indices were compared in three situations: 1) prior to any aponeurotic undermining; 2) after the incision of the anterior rectus sheath and the undermining of the rectus muscle from its posterior sheath; and 3) after additionally releasing and undermining of the external oblique muscle. The experimental model described showed to be feasible to demonstrate the effects on tension of the abdominal wall after incisions and undermining of its muscles and aponeurosis.

O uso de cadáver como modelo experimental para a avaliação da tensão da parede abdominal após incisões aponeuróticas e descolamentos musculares é descrito neste artigo. A tensão necessária para levar a aponeurose anterior e posterior do músculo reto até a linha média foi estudada em cadáveres frescos em dois níveis: 3 cm superior e 2 cm inferiormente à cicatriz umbilical. As medidas de tração foram realizadas com o uso de um dinamômetro aclopado às alças realizadas com fio de sutura na aponeurose anterior e posterior dos retos, próximas à linha média, nos níveis supra e infra-umbilicais. A tração utilizada para mobilizar os pontos aponeuróticos até a linha média e seu deslocamento resultante foram denominados coeficiente de tração. Estes índices foram comparados em três situações: 1) anteriormente a qualquer descolamento; 2) após a incisão da aponeurose anterior do reto e o descolamento do músculo reto de sua aponeurose posterior; e 3) após, além da manobra anterior, a liberação e descolamento do músculo oblíquo externo. O modelo experimental descrito mostrou-se factível na avaliação da alteração da tensão na parede abdominal após incisões e descolamentos destes músculos e aponeuroses.