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1.
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.  相似文献   

2.
The bioactive glass ceramic "Ceravital" was used to fashion prostheses for the replacement of various ossicles in the middle ear. They were tested in 70 rabbit ears, where they were accepted in osseous areas without formation of surrounding fibrous tissue. Histological examinations regularly showed an osseous bond with the surrounding bony tissue. Mucous membrane covered these ossicular chain prostheses and showed no evidence of inflammatory reactions. Glass ceramic implants were also used to reconstruct the ossicular chain and the posterior wall of the outer ear canal in 100 patients. The functional results were satisfactory in all cases.  相似文献   

3.
Nasal reconstruction presents a significant challenge to the facial plastic surgeon. Reestablishment of the desired aesthetic nasal contour and restoration of respiratory function are the dual goals of this endeavor. While autologous cartilage or bone is considered optimal grafting material, the supply is often limited and harvesting entails additional morbidity. Many synthetic materials have been introduced for use in nasal reconstruction, but high infection and extrusion rates have left most surgeons dissatisfied with conventional implants. Porous polyethylene (Medpor) implants were used for nasal reconstruction in 187 patients; 66 (35.3%) patients underwent primary rhinoplasty, while revision surgery was performed in 121 (64.7%) patients. Most patients required multiple implants, including columella struts, plumper grafts, dorsal tip implants, and nasal valve battens. Postoperative follow-up ranged from 6 months to 3.5 years. Complications occurred in five (2.6%) patients. Three early and two delayed infections necessitated implant removal in five patients, all of whom had compromised skin-soft tissue envelopes secondary to heavy smoking, cocaine abuse, or prior surgery. One case of an overly augmented nasal dorsum and tip required implant removal, reduction, and reinsertion. All implants were easily removed. No other complications including implant extrusion or skin erosion have been noted. Porous polyethylene (Medpor) implants allow for fibrovascular ingrowth, which lends stability to the implant. Porous polyethylene implants are well tolerated and provide an ideal material for nasal reconstruction.  相似文献   

4.
OBJECTIVE: Titanium in other parts of the body, well known for its biocompatibility, was examined in an animal model for its use as an ossicular replacement material. STUDY DESIGN: The biocompatibility of titanium was studied in the middle ear of rabbits using light and scanning electron microscopy. Titanium pins were placed as middle ear prostheses or as free implants and were examined after 28, 84, 168, and 336 days. RESULTS: After 28 days, the prostheses were covered by regular mucosa. The free implants took up to 336 days to be totally epithelialized. There were no inflammatory cells observed on the surface of the material nor were unusual amounts of fibrous tissue seen. In addition, the titanium material exhibited an affinity toward bone. CONCLUSIONS: The results of this animal experiment indicate that titanium is a useful material for ossicular replacement prostheses.  相似文献   

5.
The successful surgical treatment of chronic otitis media or its sequela is frequently related to a ventilated tympanic cavity. Tubes at tympanoplasty have been recommended to assure ventilation until eustachian tube and middle ear mucosal functions have been restored and to prevent the complications of graft loss, atelectasis, cholesteatoma and ossicular destruction. This presentation reviews the literature on the subject and documents our results in 40 patients treated by tympanomastoid surgery with ventilating tubes. The types of tubes used, the surgical technique involved, and the selection of cases suitable for this method are described. Cholesteatoma was the primary disease in 32 patients, 6 had chronic otitis media, 1 cholesterol granuloma, and 1 eosinophilic granuloma. Complete healing of grafts following extrusion or removal of the tubes occurred in 34 patients, 2 tubes remain in place, 3 patients had persistent tube site perforations, and 1 was lost to follow-up. None of the patients had graft breakdown as a result of tube placement, and there has been no recurrence of cholesteatoma. In all cases, the follow-up period is a minimum of 18 months and extends to 92 months.  相似文献   

6.
The middle ear poses unique challenges when finding suitable materials for ossicular reconstruction, primarily because of its link to the external environment via the eustachian tube and, hence, its greater exposure to infectious agents. In this study, the biocompatability of titanium was examined in the middle ear of rabbits by using light and scanning electron microscopy. Implants were placed as middle ear prostheses or as free implants. These were inspected at 28 days, 84 days, 168 days, 336 days and 504 days following implantation for mucosal coverage, percent epithelization and any sign of foreign-body reaction. After 28 days, the prostheses were covered by regular mucosa. Although a majority of the free implants took up to 336 days for complete epithelialization, some of the free implants were not epithelialized even at day 504. There were no inflammatory cells observed on the surface of the material, nor were unusual amounts of fibrous tissue seen. In addition, the titanium material exhibited an affinity toward bone. The results of this animal experiment indicate that titanium is a favorable material for ossicular replacement prostheses.  相似文献   

7.
Trauma has become the most common pathologic entity requiring operative intervention in the frontal sinus. Treatment has evolved from simple open drainage to ablation with reconstruction at a later date. Methyl-methacrylate, currently the most widely used alloplastic material, has inherent disadvantages such as two-stage reconstruction, difficulty in handling and molding, and susceptibility to trauma. The present investigation evaluates Proplast, a biocompatible Teflon fluorocarbon polymer implant, in one and two-stage frontal reconstruction following traumatic defects to the canine frontal sinus. Following the loss of anterior or posterior frontal bone, Proplast provided excellent cosmetic reconstruction over a period of one year. Resistance to infection was good, reaction with dura and brain was absent, and cerebrospinal fluid leaks sealed rapidly. In contrast to other alloplastic materials, rapid vascularization and collagen ingrowth lead to stabilization rather than sequestration. Several advantages over alloplastic and metallic implants may give Proplast a unique potential in operative cranioplasty.  相似文献   

8.
OBJECTIVE: To develop a measuring apparatus that has the ability to sweep both frequency and external auditory meatus static pressure and can display measurement results in a three-dimensional expression. To measure the middle ear dynamic characteristics of normal-hearing subjects and of patients with this apparatus. DESIGN: Investigate 275 ears of 153 normal-hearing subjects and 72 ears with middle ear diseases. RESULTS: The measurement results show fairly distinctive patterns depending on the middle ear conditions, i.e., normal, ossicular chain separation, ossicular chain fixation, secretory otitis media, tympanic membrane perforation, and tympanic membrane atelectasis. The evaluation of patients with ossicular diseases revealed that the rate of correct diagnosis of ossicular chain separation is 84% and that of ossicular chain fixation is 74%. These diagnoses were confirmed by surgery. CONCLUSION: Displaying the measurement results in a three-dimensional expression is helpful to make correct diagnosis in clinical practice. It is especially easy to make a distinction between the ossicular chain separation and ossicular chain fixation. Therefore, it is concluded that this apparatus has a high degree of clinical applicability to the diagnosis of these diseases.  相似文献   

9.
M Tos  G Salomon  P Bonding 《Canadian Metallurgical Quarterly》1994,73(2):92-6, 98-100, 102-3
Semi-implantable hearing aids consisting of permanent middle ear implanted magnet, either partial ossicular replacement prostheses (PORP's) or total ossicular replacement prostheses (TORP's) driven by an electromagnet placed in the ear canal have been tested on six patients undergoing surgery for chronic otitis. The surgical and audiological problems are described. The audiological results were excellent in all six cases. A functional gain of 40-70 dB can be obtained for entire frequency range of the audiogram.  相似文献   

10.
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.  相似文献   

11.
We reviewed 192 patients who had been treated for chronic otitis media. All operations were carried out at the Department of Otolaryngology, University of Tübingen. No patient had a previous ear operation and revision operations were excluded. The observation period varied from a minimum of 1 year to a maximum of 4 1/2 years. The ossicular chain was partially destroyed in 43 ears (22.4%). Ossiculoplasty was performed using autologous ossicles. An inens was used in 31 ears and a malleus in 12 cases. The overall failure rate was 20.8%. Most recurrent perforations were found in middle-aged patients. Children had only a 14% incidence of recurrent perforations. Fascia was the material associated with the highest failure rate (28.6%). After using perichondrium 6.8% of the cases had recurrent perforations, whereas the perichondrium-cartilage transplant was not successful in 4.8%. Overall, 62.7% of the patients were found to have an air-bone gap of 10 dB or less at 1.5 kHz 3-6 months after surgery. An air-bone gap of 20 dB or less was found in 91.2% of the patients. The main problem seen in the patients with chronic otitis media was not reconstruction of the ossicular chain but a lasting closure of the tympanic membrane. The perichondrium-cartilage transplant permitted the best results and is now recommended especially for patients with unfavorable middle ear conditions. A long-lasting closure of the tympanic membrane was also found in children (< or = 15 years of age). For this reason we also recommend an early operation in order to allow children to lead a normal life.  相似文献   

12.
Upper eyelid gold-weight implants are widely used in the correction of lagophthalmos in many neuromuscular conditions, most commonly facial palsy. The paralytic lagophthalmos that occurs in facioscapulohumeral muscular dystrophy (FSHD) is common and can cause severe ocular complications. It is not usually considered for surgical correction. Upper lid loading with 24K gold implants and reconstructive lower lid surgery in a 64-year-old woman with FSHD corrected eyelid deformity and exposure keratitis. Surgical treatment also markedly improved facial appearance. This treatment may merit wider use in FSHD.  相似文献   

13.
The authors report on their clinical experience in the reconstruction of complex facial deformities using titanium osseo-integrated implants for the retention of soft silicone prostheses. They also evaluate the importance of this surgical technique as a viable alternative to traditional reconstructive procedures using autologous grafts, both in patients with severe osteomuscular defects and corrective surgery of unsuccessful reconstruction operations. The patients who underwent implantation operations were studied by CT 3D and 99m Tc SPECT (Single Photon Emission Computerized Tomography) procedures to evaluate osseo-integration at 3 weeks, 3, 6, 12, 24 months. The study demonstrates that the radiation emission peaks three weeks after surgery with the maximum bone remodeling activity, and after the functional loading of the implants, 3 months after surgery. High uptake past the eight month after surgery has never been detected and must be considered abnormal. SPECT offers the possibility of obtaining a three dimensional reconstruction of the photon emission of selected structures. The use of these nuclear medicine methods in addition to traditional-type radiological procedures introduce new possibilities, although still in the clinical experimentation phase, for the long-term follow-up of the inserted implants in craniofacial rehabilitation.  相似文献   

14.
Exposure of the facial nerve from the brainstem to the parotid can be accomplished without injury to the nerve, tympanic membrane, external auditory canal, ossicular chain, inner ear or structures within the cerebello-pontine angle. The procedure has reliably provided good results for patients who have had the proper indications with facial paralysis from Bell's palsy, herpes zoster oticus, infection, hemi-facial spasm, temporal bone fracture and tumors. The current technique for exposure through the mastoid, middle cranial fossa and retrolabyrinthine combined approaches are described. This technique, properly performed, is a valuable treatment for facial nerve lesions.  相似文献   

15.
This paper describes a new technique using a Medpor porous polyethylene pivoting helix framework for reconstruction of the burned auricle. The polyethylene framework is composed of two distinct components, a curved shape that represents the helical rim which pivots around a base component. This framework is covered with a temporoparietal fascia flap and a skin graft that is chosen to match the adjacent resurfaced facial burn. The porous framework then becomes rapidly vascularized with soft-tissue ingrowth and collagen deposition. The pivoting helix design can be used to create an auricle of almost any size or projection. The helix can move independently and can be compressed against the head in the event of external pressure on the ear. The resultant ear reconstruction is extremely durable and remains flexible over time. Twenty-six consecutive ear reconstructions were performed using this method over a 2-year period. Two exposures occurred which were managed without removal of the implant. All reconstructions successfully restored an ear that was both aesthetically pleasing and functional so as to provide support for a pair of eyeglasses. The Medpor porous polyethylene pivoting helix framework offers an excellent solution for a difficult reconstructive problem.  相似文献   

16.
Plasti-pore, a high-density polyethylene sponge, was one of the earliest biocompatible materials developed specifically for implantation in the middle ear. It is one of the most nonreactive materials known when tested in simulated biochemical exposure to pseudoextracellular fluid. The two basic prosthetic designs are the total ossicular replacement prosthesis and the partial ossicular replacement prosthesis. Plasti-pore implants have now been used for 20 years and are widely accepted by otologic surgeons. The basic properties of the material, implant design, and surgical techniques involved using these prostheses are reviewed in this article.  相似文献   

17.
Using the guinea pig middle ear model, we assessed decalcified, lyophylized, sterile heterotopic porcine ossicular xeno-implants based on a histology (optic and electron scan microscope) and immunologic (immunofluorscence) methods. Implants were placed in the middle ear and others in the dorsal subcutaneous area. Allo-implants were compared as controls. Implants were placed in the middle ear in 54 animals and skin implants in 14. Under the influence of BMP, the implant ossified in all cases in the middle ear. Intense immune recruitment was not observed. Inversely, there was a mononuclear infiltration reaction to the skin implants with formation of a fibrous capsule, immunoglobulin and complement influx and consequently sequestration. The allo-implants were partially reossified. These findings confirm the value of decalcification with hydrochloric acid for BMP induction, independent of species and the failure of attempted immune despecification. Implant outcome is not dependent on its antigen load, which is high compared with its weight, but on the site of implantation. The middle ear appears to be a privileged site of implantation.  相似文献   

18.
OBJECTIVE: To evaluate the use of osseointegrated implants to fix facial and auricular prostheses. DESIGN: Retrospective. SETTING: University Hospital Groningen, the Netherlands. METHODS: Thirty patients were treated with Br?nemark implants for fixation of auricular (21 patients) and orbital (9 patients) prostheses during May 1988-December 1995. The complications during the procedure, the success rate of the implants, skin reactions around the implants and patient satisfaction were recorded. RESULTS: A total of 97 implants were placed. One implant had to be removed after the healing period because it was loose. No other implants were lost during the follow-up period (mean 36 months; range: 12-91). The skin around the implants sometimes showed a mild reaction which could be adequately treated. In most of the cases no inflammation of the skin was observed. Retention, ease of handling and wearing comfort of the facial prostheses were excellent. CONCLUSION: Fixation of facial and auricular prostheses can be improved by osseointegrated implants resulting in high patient satisfaction.  相似文献   

19.
Temporalis fascia remains the most widespread material for reconstructing the tympanic membrane in tympanomastoid surgery. If total or partial ossicular replacement prostheses are needed or pathology of the eustachian tube causes ventilation impairment, a more rigid transplant material is required. Between 1989 and 1994 perichondrium-cartilage composite grafts were used in a series of 597 cases of tympanomastoid surgery performed at the University ENT Clinic of Würzburg. The graft was taken from the tragus and prepared as a cartilage island with perichondrium attached to one side, the perichondrium-cartilage island transplant (PCI). If reconstruction of the ossicular chain was necessary, glass ionomer cement protheses (IONOS) were used. Closure of the tympanic membrane could be achieved in 90% of all cases. In those cases where ossicular chain reconstruction was postponed to a second procedure, closure of the drum was achieved in 96%. The audiological results of the different type III procedures were evaluated. By using the PCI technique a favorable closure of the air-bone gap to 10-25 dB was achieved, even in cases with advanced ear pathology technique and results are presented in detail.  相似文献   

20.
DA Cottrell  LM Wolford 《Canadian Metallurgical Quarterly》1998,56(8):935-41; discussion 941-2
PURPOSE: This prospective study was designed to evaluate the long-term clinical and radiographic results of porous block hydroxyapatite (PBHA) used as a synthetic bone graft in orthognathic surgery and craniofacial augmentation. PATIENTS AND MATERIALS: A total of 245 consecutive patients were treated initially. Inclusion criteria for this study included a minimum clinical and radiographic follow-up of 5 years. In addition, all patients with known implant failures were included regardless of whether they met the study criteria. There were 111 patients that met the criteria for inclusion in this study. All patients had undergone orthognathic surgery with rigid fixation and had had inlay or onlay PBHA implants placed. Ninety-six percent of the implants were placed through an intraoral approach. Long-term postoperative radiographs were visually compared with immediate postoperative radiographs for implant position, stability, resorption, and other significant radiographic changes. The clinical examination evaluated for signs and symptoms of infection, wound dehiscence, implant exposure, implant displacement, changes in the overlying mucosa, and development of oronasal or oroantral fistulae. RESULTS: Four hundred seventy-one implants were placed: 403 in the maxilla, 44 in the mandible, and 24 in the periorbital region. There were 289 implants placed in direct communication with the maxillary sinus. The average follow-up time was 7.2 years (range, 5.0 to 10.3 years). Twenty-three implants (4.9%) were removed during the evaluation period. Lateral maxillary wall grafting had 95.7% success, with nine implants being lost in three patients. One chin implant was removed because of dissatisfaction with the aesthetics. Seven (14%) midpalatal implants used for maxillary expansion were lost, primarily because of exposure of the implant to the oral or nasal cavity at the time of surgery. When PBHA was used for alveolar cleft grafting, there was a 100% failure rate. CONCLUSION: The use of PBHA as a bone graft substitute in orthognathic surgery and for facial augmentation showed a high percentage of success and efficacy. However, adequate soft tissue coverage in the nasal floor and on the palate are paramount for success of midpalatal implants. PBHA should not be used for alveolar cleft grafting. Rigid fixation for inlay implants in the maxilla is important to provide stress shielding of the material and minimize micromovement during the initial healing phase.  相似文献   

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