Uso del polietileno poroso de alta densidad como alternativa en reconstrucción de fracturas orbitarias. Serie de 22 casos / Use of high-density porous polyethylene as an alternative in orbital fracture reconstruction. 22 Case series

Introducción: las fracturas de pared de órbita pueden producir secuelas funcionales y estéticas. La indicación de reconstrucción quirúrgica, es indispensable para la recuperación de la motilidad y estética ocular. Los materiales reconstructivos más utilizados son los aloplásticos, como el titanio y el polietileno poroso de alta densidad (PPAD), el cual ha resultado exitoso en reconstrucción maxilofacial. El propósito de este estudio retrospectivo, es exponer los resultados tras el uso del PPAD en reconstrucciones orbitarias y sus posibles complicaciones. Materiales y métodos: se realizó una revisión retrospectiva de 22 pacientes donde se utilizó PPAD como material de reconstrucción en fracturas orbitarias. Se consideró para la indicación quirúrgica que el paciente presentara alguno de los siguientes signos: diplopía o síntomas vasovagales por atrapamiento muscular, restricciones en la motilidad ocular, enoftalmo mayor a 4mm. El material utilizado fue PPAD (Medpor Stryker®) puro en 17 casos y PPAD reforzado con una malla de titanio en el interior de su estructura (Medpor Titan Stryker®), en los 5 restantes. Resultados: se registraron 3 casos con complicaciones; ectropión, diplopía y ectropión con diplopía, los cuales todos fueron reversibles. No se registraron casos de infección ni complicaciones oftalmológicas postoperatoria. Discusión: los injertos autólogos fueron los primeros utilizados con resultados de compatibilidad y resistencia óptimos. El uso de PPAD como material de reconstrucción ha sido bien documentado con buenos resultados en términos de una baja incidencia de infección y óptima motilidad ocular a largo plazo.

Introduction: Orbital wall fractures can cause functional and aesthetic sequelae. When there is an indication for surgical reconstruction, this is essential for the recovery of ocular motility and aesthetics. The most commonly used reconstructive materials are alloplastics, such as titanium and porous high-density polyethylene (PPAD), which have been successful in maxillofacial reconstruction. The purpose of this retrospective study is to present the results and their possible complications in orbital reconstruction with PPAD. Materials and methods: a retrospective review of 22 patients in whom PPAD was used as reconstruction material for orbital fractures was performed. It was considered for the surgical indication that the patient presented any of the following signs: diplopia or vasovagal symptoms due to muscle entrapment, ocular motility restrictions, enophthalmos greater than 4mm. The material used was pure PPAD (Medpor Stryker®) in 17 cases, and PPAD reinforced with a titanium mesh inside its structure (Medpor Titan Stryker®), in the remaining 5. Results: 3 patients with complications were registered; ectropion, diplopia, and ectropion with diplopia, all of which were reversible. There were no cases of postoperative infection or ophthalmological complications. Discussion: Autologous grafts were the first used with optimal compatibility and resistance results. The use of PPAD as a reconstruction material has been well documented with good results in terms of a low incidence of infection and optimal long-term ocular motility

Complete Septal Extension Graft using Porous High-Density Polyethylene Sheet or Septal Cartilage in Unilateral Cleft Lip Nasal Deformities: Photogrammetric Analysis

PURPOSE: Complete septal extension grafts have been widely used in rhinoplasty for effective projection of the short retruded columella in Asian patients. Autologous septal cartilages and porous high-density polyethylene sheets are frequently used as septal extension grafts. This study was conducted to compare the postoperative results of porous polyethylene sheets and septal cartilages used for correction of unilateral cleft lip nasal deformities by using photogrammetric analysis. METHODS: This study investigated a total of 49 patients with cleft lip nasal deformities who underwent corrective surgery, and were followed up for at least 6 months. Septal cartilages were used in 39 patients, and porous polyethylene sheets were used in 10 patients. In all patients, through the open rhinoplasty, complete septal extension grafts were sutured to the caudal margin of the septal cartilage, and the alar cartilage was sutured with suspension. The cleft side alar cartilage was overcorrected by approximately 3 - 5 mm. Postoperative outcomes were evaluated by using photogrammetric analysis. Five indices and 4 angles were measured on their photographs taken before and after the surgery. In patients with unilateral cleft lip nasal deformities, symmetry was also evaluated by means of columellar length index. RESULTS: The postoperative values obtained in photogrammetric analysis showed improvements in comparison with the preoperative ones. The polyethylene group produced more improved outcomes than the septal cartilage group but also resulted in more complications at the same time. CONCLUSION: The results of this study indicates that complete septal extension grafts are efficient for the correction of unilateral cleft lip nasal deformities. However, since postoperative complications occur more frequently in the polyethylene group than in the septal cartilage group, caution is advised in using porous high-density polyethylene sheets in patients with cleft lip nasal deformities.

Application of porous high-density polyethylene combined with auricular cartilage in nasal tip plasty / 中华医学美学美容杂志

Objective To explore the methodology and the indications of applying the porous high-density polyethylene(Medpor)combined with auricular cartilage in nasal plasty.Methods A total of 36 cases of nasal plasty were treated with the 8.5 mm thick Medpor implant(speader strut graft)and combined with the auricular cartilage graft to highlight the nasal tip.Results All 36 cases were satisfactory with the effects,and there were no complications such as infection,exposure of the implants and so on.Conclusions Medpor can supply the powerful supporting strength to the nasal tip,and it is a safe,effective implant to rebuild the supporting constructions of nasal tip,especially suitable to correct the over-rotation of nasal tip,flat nasal tip,and short nose.

Application of high-density porous polyethylene implant in chin augmentation in contour plastic surgery of low face / 中华医学美学美容杂志

Objective High-density porous polyethylene(Medpor)has been widely used in chin augmentation in recent years.The study aimed to observe the outcomes of clinical use of high-density porous polyethylene implant in chin augmentation in contour plastic surgery of low face.Methods From 2005 to 2008,149 cases of chin augmentations intraorally with Medpor implants combined with were collected.121 of them received bilateral mandibular angle osteotomy and 28 cases received bilateral mandibular angle osteotomy and bilateral malar reduction simultaneously.They wre all females aged from 17 to 46 years.The patients were followed up for 6 to 36 months(average 24 months)and photographs were taken before and after operations.Clinical outcomes were observed and analysed.Resuits 145 patients(97.3%)were satisfied with their chin and contour of low face.2 patients (1.3%)were not satisfied with the projection of their chin,and 1 of them were admitted to take out the implant and received sliding advancement genioplasty.1 patient(0.7 0A)felt the implants was too large to some extent and was admitted to modify the implant.1 patient(0.7%)received genioplasty 6months after operation because of the deviation of the implant.20 patients(13.4%)felt numbness of the lower lip which gradually disappeared 1 to 3 months postoperatively.Complications such as infection,edema and extrusion,break of the implant were not found during the following period.Conclusions Medpor is an excellent biomaterial with good biocompatibility.Simultaneously chin augmentation with Medpor combined with bilateral mandibular angle osteotomy intraorally shows a good result in contour plastic surgery of low face.

Augmentation of Pyriform Margin Using Porous High-Density Polyethylene Sheet In Unilateral Cleft Lip Nasal Deformity

PURPOSE: The common deformity after the correction of unilateral cleft lip nasal deformity is nasal asymmetry, and it is caused by the hypoplasia of the pyriform aperture. To correct this, many procedures have been applied, but still many problems are present. Authors performed the inlay and onlay insertion of porous high density polyethylene sheet(1mm thickness Medpor(R) sheet) in the hypoplastic pyriform margin of cleft side and obtained satisfactory results. METHODS: 11 cases were performed and the mean follow up period was 15.1 months. Their mean age was 23.6 years. Under general anesthesia, bilateral pyriform margin was exposed. Medpor(R) sheets in "match stick" like shaped were inlay inserted, and kidney shaped were onlay inserted fixating with two 6mm titanium screws. After the surgery, the results was evaluated by photogrammetric analysis. On the basal view, the distance from the subalare and labiale superius' to the transverse baseline connecting the both cheilions was measured from the cleft side and the non-cleft side. Then, the postoperative symmetry was assessed by obtaining the cleft side against the non-cleft side as proportion index, defined as lateral and medial upper lip contour index. RESULTS: There were 2 infections. The cause was because the inserted implant was too long and thus protruded to the base of nasal cavity. The lateral upper lip contour index was from 95.49 to 103.27, and medial upper lip contour index was from 90.92 to 100.49, it was statistically increased, and thus the symmetry was improved. However clinically mild depression remained at nostril floor. CONCLUSION: Authors performed porous high density polyethylene sheet inlay and onlay insertion for the hypoplasia of the pyriform margin in unilateral cleft lip nasal deformity. It was found that depressed pyriform margin and upper lip were corrected effectively except for the nostril floor, for which an additional soft tissue augmentation would be necessary. The inlay insertion has risk of protrusion, thus the guideline of the use of artificial prosthesis should be observed strictly.

The Correction of Mild Hemifacial Microsomia: Polyethylene Implantation, Lateral Cortectomy, and Osseous Genioplasty

Hemifacial microsomia is a condition most frequently associated with facial asymmetry. Authors have experienced eighteen patients with mild hemifacial microsomia who were classified as type IA and IB. For the correction of mandibular asymmetry, mandibular augmentation was performed on the mandibular angle of the affected side using mandibule shaped porous high-density polyethylene(Medpor(R)) in thirteen patients. Reduction mandibuloplasty was performed on the mandibular angle of the normal side using lateral cortectomy in four patients, and genioplasties were used in 2 patients. Osseous genioplasty(n=10), buccal fat removal(n=4), augmentation rhinoplasty(n=2), and onlay bone graft(n=1) as ancillary procedures were simultaneously executed. Except for 4 patients in whom the implants were removed due to exposure and infection, all other patients were satisfied with a more symmetric contour of their face. The results were clinically evaluated through ordinary scale method and photogrammetric analysis. The mean score was rated 'good' as 12.5 points, and the mean bigonial distance index and the mean gonion-midsagittal distance index were 105.20%(p=0.035) and 100.65%(p=0.368), respectively, which meant a more symmetry of the lower face. In minor asymmetry of the mandible in cases of hemifacial microsomia, augmentation with cautions of the affected side, reduction with lateral cortectomy of the mandible in the non-affected side, and an even osseous genioplasty can provide the patient with a more symmetric lower face.

A Correction Of Unilateral Cleft Lip Nose Deformity using Porous High-density Polyethylene Columellar Strut

Even though many surgical techniques have been reported to correct the unilateral cleft lip nose deformity, it is very difficult to achieve optimal results. The authors used the porous high-density polyethylene(Medpor(R)) sheet as a columellar strut for alar cartilage repositioning and the triangular transposition flap based on the superior columella for correction of excess skin of alar web. A silicone implant was used for nasal dorsal augmentation. Additional techniques including segmental resection of the excessive alar cartilage on the normal side, freeing of the septal cartilage from the vomer, the nasal osteotomies, a Z-plasty on the afftected plica vestibularis, alar advancement of denuded alar base flap or an interalar cinch, and subcutaneous reduction of the external lateral triangle were also used to repair individual differences of the nasal deformities. Twenty-four patients (11 females and 13 males; mean age, 24 years) were included in this study. From six to thirty-four months(mean fifteen months) postoperatively, the patients were evaluated by the ordinary scale method and the anthropometric analysis using preoperative and postoperative nasal cast models. The analysis of the result was conducted by Paired samples T test. All the patients showed uneventful healing except three cases of columellar strut protrusion. By the ordinary scale method, "good" aesthetic results were noted. By the postoperative anthropometric analysis, the alar length of the normal side, the columellar length and the tip projection of both normal and affected sides were significantly increased. The nostril floor width of the affected side and the nose width were significantly decreased. In conclusion, this technique is valuable in the correction of unilateral cleft lip nasal deformity. But in cases of severe deformity, residual septal deviation, those who have received the operation several times, the porous high-density polyethylene sheet must be used carefully because of the protrusion.

A Correction of Hypoplastic Mandible Using Mandibular Shape Porous High Density Polyethylene (PHDPE)

The mandible with the lower maxilla comprises the lower third of the face. A correction of the mandible in facial asymmetry would be helpful in improving aesthetic appearance. In general, surgical techniques for improving the contour of lower jaw deformities include correcting the deficient mandible by osteotomies, distraction osteogenesis and the augmentation of the mandible with alloplastic or autogenous materials. In a patient with satisfactory occlusal relationships and mild hypoplasia, alloplastic material for augmentation of the mandible on the affected side is more practical than autogenous augmentation. The porous high density polyethylene (PHDPE) implant is a widely available alloplast which is an attractive alternative to other alloplasts and autogenous tissues. Thirteen patients (8 men, 5 women), ages ranging from 17 to 47 years old, have types IA (n = 6) and IB (n = 5) hemifacial microsomia(Munro and Lauritzen, 1985), Klippel-Feil syndrome (n = 1), Romberg's disease (n = 1) were corrected with prefabricated porous high density polyethylene over a 4 year period (1996- 1999). The average follow-up period was 12 months, however the range has been between 6 and 36 months. Preoperative planning was done based on an aesthetic assessment of thickness of the soft tissue, the use of life size photographs, cephalometric and panorex x-rays and three dimensional computed tomography. The surgical technique consists of an intraoral approach incision, the an implant was placed subperiostealy, appropriately sculptured and fixed to posterior and inferior border of the mandible at the gonial angle. In four patients the implant had to be removed due to complications which included three cases of infection and one case of extrusion by iatrogenic trauma. One of the above four patients' implant was replaced with a smaller one, approximately 3 months after its removal. With the others nine patients there was no infection or permanent morbidity. Postoperative appearance was considered very satisfactory, the mandible was well outlined, and the facial proportions were improved. Porous high density polyethylene implant is recommended for hypoplastic mandible augmentation when proper indication are strictly observed and surgical steps are accurately followed.

Treatment of Medial Orbital Wall Fracture Using Medial Transconjunctival Approach

The term of blow-out fracture refers to a fracture of an orbital wall, typically the orbital floor or medial wall. Especially the medial blow-out fracture is difficulty to approach. Transcutaneous approaches could remain postoperative scars and transconjunctival approaches could give bad visual field and technically difficulties in approaching the medial orbital wall. But the medial transconjunctival incision could avoid an external scar, save the operating time, and decrease injuries of surrounding tissue. Authors operated the medial blow-out fractures through the medial transconjunctival approach and porous high-density polyethylene sheet was placed on fracture site for the prevention of relapse of the orbital contents. 30 cases of medial blow-out fractures were treated using the medial transconjunctival incision. All patients were corrected satisfactorily without leaving any visible scar. Thus the medial transconjunctival approach was an effective way to repair medial blow-out fracture.

The Clinical Use of Various Nasal Implants in Rhinoplasty

From an aesthetic surgical point of view, rhinoplasty is one of most important field. The nose of asian is characterized by thin and weak nasal septal cartilage, wide and small alar cartilage, bulbous nasal tip due to excessive fibrous tissue and thick skin. Conventional rhinoplasty is not enough to get a satisfactory result. In order to produce optimal nasal shape, it is extremely important to augment the tip along with nasal dorsum in most of the patients. From March of 1997 to June of 1999, total 162 patient underwent open rhinoplasty with various nasal implants. Surgical approach was done through the transcolumella incision and alar rim incision. The nasal dorsum was augmented with silicone implant, and columella shape was controlled by 0.85-mm thickness porous high-density polyethylene sheet(Medpor). Porous high-density polyethylene sheet was 4mm width and was placed between the medial crura. The nasal tip was corrected by Polytetrafluoroethylene(Gore-Tex) implant. Reverse pyramidal shaped onlay graft of Polytetrafluoroethylene(Gore-Tex"") implant was not palpable on nasal tip skin. We obtained harmonious nasal shape and high patient satisfaction. There was two infection and one exposure of Polytetra- fluoroethylene(Gore-Tex) implant, but there was no other major complications. We believe that this method is stable, reliable, predictable, valuable technique for rhinoplasty, but we think that further follow up and study are needed.