Pectoralis major myocutaneous flap for reconstruction of defects following resections in head and neck area

Pectoralis major myocutaneous flap (PMMF) has become the standard for reconstruction of major defects in head and neck area. Eleven cases, operated over a three year period, in which PMMF was used for reconstruction have been reviewed retrospectively. Nine patients had oral squamous cell carcinoma, one had a basal cell carcinoma of the external ear and one had lost skin and soft tissue of neck following synergistic gangrene. Ten of the eleven flaps survived (success rate 91%). One of the three rib grafts used to reconstruct mandible got infected and had to be removed. Three patients developed wound infections and one had a temporary orocutaneous fistula which closed spontaneously. This brief experience confirms the reliability and efficiency of PMMF for head and neck reconstruction.     

Epitope analysis of the human p53 tumour suppressor protein

Allogenic, preserved cartilage is often used for reconstruction of face. This study was undertaken to analyze the effects of cartilage transplantation. In analyzed group of 437 patients after cartilage transplantation, 42.2% were operated because of posttraumatical changes, 29.0% because of congenital malformations. In 16.7% nonspecific inflammations were the cause of reconstructive operations. Malformations were mainly localised in nose 59%, ear concha 16.5% and mandible 10.9%. Human costal cartilage, preserved in 0.9% NaCl and radiation-sterilized was used for reconstruction. 24-190 months after surgery (in several clinical units) patients were examined and results were collected in special questionnaire by the team who performed surgery. The results of treatment were compared with age, diagnosis and localisation of changes. It was found that very good result of treatment was achieved in 33.5% of patients, in 41.8% result was satisfactory. In 19.9% of operated patients result of treatment was unsatisfactory. Correlation of some clinical and biological characteristics with the result of treatment is discussed.     

Coevolution of the mammalian middle ear and neocortex

Phylogenetic analysis with x-ray computed tomography of fossilized and recent crania implicates differential growth of the neocortex in the evolution and development of the mammalian middle ear. In premammalian tetrapods, the middle ear evolved as a chain of bones attached to the mandible and cranium, but in adult mammals the chain is detached from the mandible and lies behind it. The neocortex evolved concurrently with detachment of the chain. In mammalian development the auditory chain arises connected to the mandible but later detaches, recapitulating the phylogenetic transformation. In modern didelphid development, the auditory chain reaches mature size by the third week after birth and is then separated from the jaw and displaced caudally as the neocortex grows for another 9 weeks.     

Reconstruction of the mandible with conventional bone graft: an evaluation

Eighteen patients with bony defects of the mandible had the mandible reconstructed using conventional nonvascularized bone grafts from the iliac crest. After surgery they received radiotherapy for cancer in the oropharynx or oral cavity. This study was carried out over a 10-year period. All patients were followed-up both for their tumour growth and the results of their reconstruction. Four to 10 years after surgery 55.5 per cent were alive and well. Full dental rehabilitation was achieved in 33 percent and 12.5 percent were without dental rehabilitation.     

The expression of regenerative growth factors in chronic liver injury and repair

The outcomes of surgical reconstruction for patients who have undergone extensive tumor resection of the mandible and associated soft tissue have been less than desirable for many reasons: lack of cancer cure, radiation problems, as well as inadequate functional reconstructive results. These patients traditionally have undergone multiple surgical procedures for restoration of the surgical deformity. With the advent of new donor sites and successful transfer of microvascular hard and soft tissue, one can restore the largest defects created during cancer excision. Combining these techniques with biocompatible dental implants and reconstructive bone plates, technology has advanced to the point of predictable outcomes. The restoration of appearance, mandibular function, and mastication is mandated by patients. Dental implants are now placed in vascularized bone reconstruction of the mandible immediately at the time of ablative surgery. This obviates the need for additional surgical reconstructive procedures, adjunctive hyperbaric oxygen therapy, and problems associated with the placement of dental implants in irradiated tissue.     

Increase in skeletal muscle protein content by the beta-2 selective adrenergic agonist clenbuterol exacerbates hypoalbuminemia in rats fed a low-protein diet

Between 1990 and 1995, 214 implants were placed in 29 maxillae and mandibles of 22 patients following extraction of all residual teeth as a consequence of severe periodontal disease. All patients were discharged wearing immediate dentures. The implants were analyzed with regard to the number per arch, location, length, and diameter. The 5-year cumulative survival rate was 98.5%. The mean number of implants per arch was 7.5 for the maxilla and 7.2 for the mandible. The preferred implant locations were canines, central incisors, lateral incisors, and second premolars in the maxilla; and lateral incisors, first molars, and canines in the mandible. The mean implant length was 14.7 mm in the mandible and 14.5 mm in the maxilla. The mean implant diameter was 3.8 mm in the maxilla and 3.8 mm in the mandible. The results of the present study indicate that immediate implantation for fixed full-arch reconstruction can be considered a viable treatment alternative in patients with severe periodontal disease.     

基于三维人耳形变模型的三维人耳重建

基于对已有三维人耳重建工作和形变模型理论的研究,充分结合人耳自身的结构特征,提出了一种新的三维人耳重建方法——基于人耳形变模型的方法.首先使用中垂线法完成了外耳轮廓特征点的定位;提出分级三角网格法,解决了样本耳基于生理特征的稠密对应问题;再借鉴广义普鲁克分析的思想,在三维空间内实现了精确全自动的三维人耳形状对齐;最后训练得到了三维人耳形变模型.所提方法只需一幅二维图像,即可获得足够稠密的三维人耳模型.在UND三维人耳数据库和USTB三维重建人耳数据库上的大量实验证明所提方法的有效性和优越性.      

Mandibular reconstruction using a microvascular method in the transplantation of a fibular flap

The best results in mandibular reconstruction are achieved by transplantation of vascularised bone. This transplant has an own blood supply therefore its surviving is not influenced by the non-sterile environment of the oral cavity and the insufficient blood supply of the operated area (caused by scar or radiation). A new promising method for reconstruction of a wide segmented defect of the mandible is vascularised fibular flap transplantation. Eight consecutive patients treated with fibular flap transplantation in 1993 and 1994 were reviewed. Osteo- and osteo-cutan flaps were used for reconstruction of the composite tissue defects. The authors report on the surgical technique and their first experiences. The authors consider the application of the fibular flap the most successful procedure of all types of reconstruction of segmented mandibular defect.     

An adult case of extra-hepatic portal obstruction with bleeding from esophageal varices

PURPOSE: This study examined the use of a locking reconstruction bone plate/screw system for use in mandibular surgery. PATIENTS AND METHODS: All patients treated with a locking reconstruction bone plate/screw system for fractures of the mandible or continuity defects in an 18-month period were prospectively studied. Ease of use of the locking plate/screw system, characteristics of the fractures/defects, and complications were tabulated. RESULTS: One hundred two locking bone plates were placed in 84 patients. Most patients (n=75) were treated for fractures of the mandible; there were eight continuity defects and one case of mandibular narrowing. There were no cases of malocclusion or difficulties encountered in using the plate/screw system. Loss of fixation was encountered in only one patient. CONCLUSIONS: The use of a locking plate/screw system was found to be simple, and it offers advantages over conventional bone plates by not requiring the plate to be compressed to the bone to provide stability.     

Experience with segmental reconstruction of the radiated mandible with alloplastic prostheses

Reconstruction of the mandible after radiation therapy and segmental resection is often complicated by wound breakdown, osteoradionecrosis, and crippling of the oral cavity. These complications make patient salvage after radiated oral carcinoma a high-risk endeavor. Although head and neck surgeons have improved the reliability of mandibular reconstruction with microvascular free tissue transfer, medical and oncologic issues may prohibit their application. This report presents 12 selected cases undergoing alloplastic reconstruction of the mandible and soft tissue reconstruction of the oral cavity. Although not as reliable as some reports of free tissue transfers, the results were reproducible and satisfactory in these cases, with time-efficient hospitalization and functional rehabilitation. Ten of 12 prosthetic reconstructions have been durable in this study population for as long as 36 months.     

A historical review of mental health services in Hong Kong (1841 to 1995)

OBJECTIVE: To review the experience of 1 microvascular surgeon during an 11-year period in performing 210 vascularized bone-containing free flaps for oromandibular reconstruction. DESIGN: Retrospective medical records review of patients who underwent primary and secondary oromandibular reconstruction with the use of vascularized bone free flaps. SETTING: Academic medical center. PATIENTS: A total of 201 patients underwent 210 composite free-flap reconstructions of the mandible for various disorders and with a range of bony and soft tissue defects. INTERVENTION: All patients underwent the microvascular transfer of vascularized bone flaps from the ilium, fibula, or scapula. In selected cases, 2 simultaneous free flaps were transferred to achieve an optimal bone and soft tissue reconstruction. Endosteal dental implants were used in 81 patients, with a total of 360 fixtures placed during these 11 years. MAIN OUTCOME MEASURES: The success of microvascular free tissue transfer, dental implant extrusion, and short- and long-term complications at the recipient and donor sites. RESULTS: Of the 210 mandibular reconstructions that were performed, 202 were successful in reestablishing mandibular continuity. Reexploration for vascular-related complications was done in 16 patients, 8 of whom were successfully treated, yielding an overall success rate of 96%. The overall success rate for endosteal dental implants was 92%. The implant success rate was 86% when the bone in which the fixtures were placed was irradiated postoperatively. The success rate was 64% in the 14 fixtures that were placed into previously irradiated bone. CONCLUSIONS: The success of the use of vascularized bone free flaps in restoring continuity to the mandible is clearly demonstrated in this series. There was an acceptable incidence of donor- and recipient-site complications that resulted in minimal long-term morbidity. The careful selection of a donor site(s) for oromandibular reconstruction allows for an optimal restoration of bony and soft tissue defects. Dental implants can be safely used in oromandibular reconstruction with a high level of success. Placing these implants during the initial surgery shortens the duration for achieving dental rehabilitation and enhances the success of the implants when postoperative radiotherapy is administered.     

Spontaneous and induced minisatellite instability in the human genome

Two patients with recurrent parotid gland carcinoma required subtotal petrosectomy and infratemporal fossa type C approach. To achieve en bloc resection, the ascending mandibular ramus and the entire temporomandibular joint, including the adjacent temporal bone, were removed. An original technique for immediate reconstruction of the infratemporal region, including the glenoid fossa and the ramus of the mandible, is described. Rigid fixation, as well as good functional and aesthetic results, was achieved with autologous calvarial bone and full-thickness rib grafts, allowing the patients to mobilize their jaw very rapidly.     

Replacement of ear ossicles with titanium prostheses

BACKGROUND: Titanium has been a well established implant material for many years. New material processing techniques now permit the manufacture of small implants for ossicular chain reconstruction. METHODS: Between November 1994 and September 1995, 100 titanium middle ear implants (55 PORP, 45 TORP) were used for reconstruction of the ossicular chain. A range of five different sizes for partial and total protheses suits all implantation needs. The shape of the implants can be altered by bending. Time consuming intraoperative shaping and trimming is avoided. RESULTS: At a follow-up time of three months (33 patients) and six months (17 patients), no adverse reactions or extrusions occurred. Biologic fixation between the foot of the partial prothesis and the head of the stapes was found eight months after implantation. A hearing result of 0-20 dB residual air-bone gap was achieved in 79%. CONCLUSION: Titanium middle ear implants show good bio-compatibility and are readily integrated into the ossicular chain. Although delicate in shape, they offer excellent mechanical properties in respect to sound conduction and implantation. Initial results show Titanium to be a perfect implant material for middle ear prostheses, although long-term results are not yet available.     

Management of the mastoid air cell system in chronic otitis media

The influence of the Mastoid Air Cell System in Chronic Otitis Media is subject to much speculation. Does a mastoidectomy influence the surgical results following chronic inflammatory ear surgery? An understanding of the pathology associated within the mastoid air cell system is necessary before a discussion of the need for a mastoidectomy can be presented. Most mastoid air cell systems are sclerotic in chronic otitis media patients. The report summarizes one author's experiences with the influence of mastoidectomy upon surgical reconstruction for chronic inflammatory diseases of the ear. Emphasis is directed toward the eustachian tube rather than the mastoid air cell system.     

Bladder cancer in a patient on long-term haemodialysis

OBJECTIVE: The results of the first cohort of 60 cavity reconstructions with hydroxyapatite with a minimum follow-up period of 15 years were studied. STUDY DESIGN: The study design was a retrospective study. PATIENTS: A total of 60 patients had a follow-up period of >15 years. In four patients, not all data were available. Therefore, 56 patients were included in the study. They had a combination of cavity problems and hearing loss. INTERVENTION: The ear canal was reconstructed with a canal wall prosthesis of porous hydroxyapatite. The ossicular chain was reconstructed with an incus or incus-stapes prosthesis of dense hydroxyapatite. RESULTS: After 15 years, 42 patients (75%) had an intact reconstructed ear canal. The main problem for failure was the recurrent purulent middle ear infection and not cholesteatoma. The histology of the retrieved canal wall showed a good remodeling in living bone tissue. After 15 years, 34 patients had a normal ear canal and an ossicular chain. Of these patients, 7.05% had an air-bone gap closure within 20 dB. CONCLUSIONS: Long-term results of cavity reconstruction with hydroxyapatite are possible. The main problem is recurrent mucosal disease of the new middle ear-mastoid cleft.     

3-dimensional computed tomography with model preparation before mandibular reconstruction

Extended mandibular defects resulting from cancer resection are amenable to reconstruction with a free vascularized bone graft transplantation. Between 1992 and 1995, 12 patients were enrolled in a protocol including a preoperative 3D-CT used to develop a custom-made acrylic model of the mandible. Besides contributing to the assessment of tumor extension, 3D-CT helps determine the adequate limits of mandibular resection. 3D-CT has the advantage of providing the surgeon with a more familiar image of the mandible and the mandibular model, allowing better and quicker conformation of the bone flap. The graft can be shaped at the donor site before cutting its vascular pedicle, resulting in a shorter period of ischemia. This series demonstrated that preoperative mandibular modeling with 3D-CT helps improve functional and cosmetic results in mandibular reconstruction.     

A comparison of vascularized and nonvascularized bone grafts for reconstruction of mandibular continuity defects

PURPOSE: This study compared vascularized and nonvascularized bone grafts for the reconstruction of segmental defects of the mandible. PATIENTS AND METHODS: The results in 39 patients having vascularized bone grafts (38 fibulas and one iliac crest) and 29 patients having nonvascularized bone grafts (26 iliac crest [22 corticocancellous block grafts, four cancellous bone grafts in a tray] and three rib grafts) for segmental mandibular reconstruction were evaluated in terms of overall success rate, total number of surgeries performed, total blood loss, total number of hospital days, and total number of hours in the operating room. RESULTS: Of 39 vascularized bone grafts, two failed (95% success rate), whereas of 29 nonvascularized bone grafts, seven failed (76% success rate). Failure for the nonvascularized bone grafts was closely correlated to the length of the defect. Nonvascularized bone graft patients underwent an average of one more surgical procedure for total reconstruction than vascularized bone graft patients, including osseointegrated implants. However, vascularized bone graft patients spent a mean of over 14 additional days in the hospital for all of their reconstructive procedures and an additional 3 hours in the operating room as compared with nonvascularized bone graft patients. Blood loss was similar in both groups (1,100 mL). Only 20% to 24% of patients in each treatment group have completed reconstruction to include osseointegrated implants. CONCLUSIONS: The success rate for vascularized bone grafting is high and is the treatment of choice when primary reconstruction is required, when the patient has been previously irradiated, or when simultaneous replacement of soft tissue is required. Vascularized bone grafts are also the treatment of choice for mandibular replacements over 9 cm in length. Nonvascularized bone grafts create a better contour and bone volume for facial esthetics and subsequent implant insertion, and may be the treatment of choice for secondary reconstruction of defects less than 9 cm in length.     

Reconstruction of mandibular continuity defects in dogs using poly (L-lactide) mesh and autogenic particulate cancellous bone and marrow: preliminary report

PURPOSE: This study evaluated the reconstruction of continuity defects in the canine mandible using a poly [L-lactide] (PLLA) mesh tray and particulate cancellous bone and marrow (PCBM). MATERIALS AND METHODS: Eight adult dogs were divided into two groups of four dogs each. In group A, each dog had a tray fixed with stainless steel wires on each side of the mandibular stumps with the concave surface of the tray attached to the inferior border of the mandible (U-fixation). In group B, the concave surface was attached to the superior border (inverted U-fixation). Each tray was filled with PCBM from the ilium. After the operation, the dogs were radiographed, and specimens were examined histologically at 3-, 6-, and 12-month intervals. RESULTS: All of group A showed good clinical healing and the continuity of the mandibular bone was regained within 3 months postoperatively. However, fibrous tissue had invaded through the area above the tray, resulting in a poorly shaped alveolar ridges. In group B, the dogs showed good bony regeneration with well-shaped alveolar ridges. However, two animals in this group had partial exposure of the PLLA mesh tray into the oral cavity. CONCLUSION: It is suggested that a combination of the PLLA mesh and PCBM grafts might be a useful technique for functional reconstruction of the jaw bone, specifically using method A (U-fixation) as a technique to reconstruct continuity defects of the mandible, and method B (inverted, U-fixation) as a promising method for alveolar reconstruction to make wearing dentures possible.     

Aspects of the humoral immune response to Staphylococcus intermedius in dogs with superficial pyoderma, deep pyoderma and anal furunculosis

In order to evaluate the long term clinical and morphologic results of recapture of a displaced TMJ disk, we recalled for follow-up MR imaging 75 patients who had been treated by attempted disk recapture based on pre-treatment MR imaging 1-6 years earlier. The treatment included a day appliance with inclines to guide the mandible into the therapeutic position and a telescopic night appliance which prevented retrusion of the mandible during sleep. Appliance treatment was followed by rebuilding or resurfacing the posterior teeth of one arch to permanently support the mandible in the therapeutic position. After treatment of 115 joints with displaced disks, 52% of the disks were normally positioned, 23% were improved in position, and 25% showed persistent disk displacement. Symptom relief was 92% in patients with normalized (recaptured) disks, 84% in patients with improved disk position, and 49% in patients with persistent disk displacement. Failure to improve disk position occurred in 7% of the joints with anterior disk displacement and in 44% of the joints with a transverse (sideways) component to the displacement. Forty-five percent of the recaptured-disks improved in contour. We concluded that anterior mandibular repositioning was effective in the treatment of patients with reducing displaced disks primarily when the disks were displaced only in an anterior direction. This treatment can be recommended in anterior disk displacements if the patient has failed more conservative treatment measures, permanent occlusal reconstruction can be justified, and the patient understands that long-term use of a night appliance may be necessary. Anterior mandibular repositioning appears much less effective in cases with a transverse component to the disk displacement.     

Fibula osteoseptocutaneous flap for reconstruction of osteoradionecrosis of the mandible

Osteoradionecrosis of the mandible poses formidable problems for treatment. In the last 6 years, the fibula osteoseptocutaneous free flap was used in 12 cases to replace mandibles with radionecrotic damage. The presence of a pathologic fracture, exposed necrotic bone, or a persistent fistula not responding to conservative treatment were the indications for such a radical approach. Mandible defects after resection were around 8.0 cm long, and in all cases intraoral mucosa, skin, or both were included with the bone excision. All vascularized fibula osteoseptocutaneous flaps transplanted were successful with good primary bone healing. Adequate facial symmetry and improvement in oral function was achieved. No evidence of osteoradionecrosis recurrence was observed after a mean follow-up period of 3 years and 9 months. The advantages of using the fibula osteoseptocutaneous flap for mandible reconstruction are numerous, and good aesthetic and functional results can be obtained when it is used for reconstruction after radical excision of osteoradionecrotic lesions.