Effect of ship-shaped expanded polytetrafluoroethylene nasal prosthesis in rhinoplasty / 中华医学美学美容杂志

Objective:To investigate the effect of ship-shaped expanded polytetrafluoroethylene (e-PTFE) nasal prosthesis in rhinoplasty.Methods:From February 2016 to June 2021, 86 patients, including 9 males and 77 females, aged 18-47 (24±5) years old, were admitted to Chengdu High-tech Zone Xinyuerong Medical Aesthetic Clinic for cosmetic treatment of rhinoplasty. All patients underwent rhinoplasty with the application of ship-shaped e-PTFE and autologous cartilage. The postoperative complications, glabellar fullness, inverted brow triangle, nasal polygon aesthetic shape and patient satisfaction were evaluated. These data were measured and analyzed, including the nasal length, nasal tip height, nasal frontal angle and nasal facial angle before and after the operation.Results:In 86 patients, the incision healed in one stage after surgery, and 8 cases had nasal vestibular scar hyperplasia. All patients were followed up for 1-5 years: 84 cases obtained satisfactory nasal morphology, and 2 cases recovered naturally after adjusting and lowering the prosthesis height half a year after surgery because the interbrow area was too full. 74 patients (86%) were very satisfied, 10 cases (11.6%) were satisfied. The nasal length was (4.07±0.20) cm, the nasal tip height was (2.66±0.36) cm, the nasal frontal angle was (106.42±8.04)°, and the nasal face angle was (15.90±0.85)°before operation. The nasal length was (4.23±0.20) cm, the nasal tip height was (2.59±0.26) cm, the naso-frontal angle was (113.69±6.34)°, and the naso-facial angle was (21.57±0.78)° at eighteen months after operation. There were statistically significant differences in nasal length, naso-frontal angle and naso-facial angle ( t=-5.51, -5.96, -52.31, P<0.01), but no statistically significant differences in nasal tip height ( t=1.47, P=0.146). Conclusions:The ship-shaped e-PTFE can be shaped to reflect the aesthetic of the nose dorsum, which is similar to the anatomical structure of the nose dorsum, increase the stability and authenticity of the prosthesis, and is worthy of clinical application.

Clinical effect of integrated prosthesis on eyebrow arch augmentation / 中华医学美学美容杂志

Objective:To explore the feasibility and advantages of integrated prosthesis of expanded polytetra-fluoroethylene (e-PTFE) in eyebrow arch augmentation.Methods:The clinical data of 45 patients with low or flat brow arch and glabellar zone from June 2019 to October 2020 in Chengdu High-tech Zone Xinyuerong Medical Aesthetic Clinic were analyzed retrospectively, in which it included 45 women, whose ages ranged from 20 to 39 years with average 29.8 years. Forty-three cases underwent primary surgery, and 2 cases underwent repair. The e-PTFE was sculpted to be personalized integrated prosthesis according to the shape of the patient's eyebrow arch and glabellar zone. The incision was designed on the medial and lateral sides of the lower margin of the bilateral eyebrow to avoid the supraorbital foramen, and the lacunae were striped under the frontal periosteum, and the two sides were connected to cover the glabellar zone and inverted triangle area between the eyebrows. The carved e-PTFE was implanted into one side and pulled out from the other side. The prosthesis was smoothed by Venn pliers of the ventral and dorsal sides.Results:The 45 patients in this group were followed up for 6-18 months. The incisions of all the patients were healed Ⅰ/A, and the scar of the incisions was concealed. Slight scalp numbness occurred in 4 patients and returned to normal 3 months later. The prosthesis in the glabellar zone appeared in 1 case 3 months after operation and returned to normal after reoperation. The symmetry, radian, fullness, convexity and tactility of bilateral eyebrow arch were all satisfactory in 45 cases. 39 cases were very satisfied, accounting for 86.7%; 6 cases (13.3%) were satisfactory. The sagittal distance of the anterior surface of the cornea to the soft tissues overlying the supraorbital rims was (2.02±1.72) mm preoperatively and (6.5±1.19) mm in the last follow-up. The difference was statistically significant ( t=14.49, P<0.01). Conclusions:This design of integral e-PTFE in eyebrow arch augmentation is safe, effective and easy to operate. It can significantly increase the bony beauty and stereoscopic sense of the eyebrow arch and glabellar zone, effectively deepen the eye socket, improve the eye protrusion, and reduce the risk of asymmetry and prosthesis displacement, and therefore it is one of the ideal methods for eyebrow arch augmentation.

Rapid and sutureless anastomosis of artificial vascular replacement of abdominal aorta in dog models using magnetic compression anastomosis technique / 器官移植

Objective To explore the feasibility of rapid and sutureless anastomosis of artificial vascular replacement of abdominal aorta in dog models using magnetic compression anastomosis (MCA) technique. Methods Twelve healthy adult crossbred dogs were evenly divided into the MCA and hand suturing (HS) groups according to the anastomosis method between abdominal aorta and artificial blood vessels. The intraoperative duration of abdominal aorta occlusion, intraoperative condition of anastomotic stoma and postoperative imaging examination of anastomotic stoma were compared between two groups. Results The intraoperative duration of abdominal aorta occlusion in the MCA group was significantly shorter than that in the HS group [(5.2±2.3) min vs. (24.4±4.3) min, P < 0.001]. No anastomotic leakage of blood or anastomotic stenosis occurred in the MCA group during the operation. Intraoperative anastomotic leakage of blood occurred in all of the 6 dogs in the HS group. Among them, 1 dog died of excessive blood loss, and 2 dogs experienced mild anastomotic stenosis due to repeated repair. Postoperative color Doppler ultrasound and angiography showed smooth blood flow at the anastomotic stoma without stenosis or thrombosis in the MCA group. In the HS group, 4 dogs presented with anastomotic stenosis on angiography at postoperative 4 weeks. Conclusions MCA technique may achieve rapid and sutureless anastomosis of artificial vascular replacement of abdominal aorta in dog models, which reduces the incidence of anastomotic complications and accelerates postoperative recovery.

Ross procedure to cure aortic valve disease in children with expended polytetrafluoraethylene(ePTFE) artificial valve for right ventricular outflow tract reconstruction / 中华胸心血管外科杂志

Objective:To review and analyze the clinical experience of children with aortic valve stenosis and/or insufficiency treated with autologous pulmonary valve for aortic valve replacement procedure(Ross operation) with ePTFE artificial valve for right ventricular outflow tract reconstruction.Methods:From 2015 to 2020, 8 cases of aortic stenosis and/or aortic insufficiency treated by Ross operation in our center were collected, with an age of 0.5-13.2 years old. 4 cases of aortic stenosis were diagnosed preoperatively, 3 cases of aortic stenosis with aortic insufficiency, and 1 case of infective endocarditis involving the aortic valve. The operation was carried out in three steps: Harvest autologous pulmonary valve; the diseased aortic valve was resected and autologous pulmonary valve was transplanted to the aorta by aortic root transplantation; the right ventricular outflow tract was reconstructed by a handmade ePTFE artificial flap blood vessel.Results:In 6 cases, the right ventricular outflow tract was reconstructed by hand-sewn ePTFE trileaflets, and artificial univalve in 2 cases, no death occurred during operation; all patients were cured and discharged. The patients were followed up for 1 to 36 months, with mean of(12.63±12.19) months. There was no long-term death or valvular complications. During follow-up echocardiography indicated 1 case of moderate aortic regurgitation, 1 case of mild-moderate regurgitation, and moderate regurgitation was found in 2 patients with artificial single pulmonary valve. For the remaining patients, they were mild aortic regurgitation, and a trivial or mild pulmonary artery regurgitation with hand-sewn three-leaflets ePTFE artificial vessel; All patients were followed up at the last time with a peak pressure of(6.63±3.46) mmHg(1 mmHg=0.133 kPa) across the aortic valve. The left ventricular outflow tract and aortic annulus shrank slightly after surgery(the diameter of one patient with Ross-Konno operation increased), but the annulus diameter increased with age. There was no need for further intervention.Conclusion:The Ross operation is safe for the treatment of aortic valve disease, it has good hemodynamic effect, and the autologous pulmonary artery has growth potential, especially suitable for children and young patients. Hand-sewn ePTFE with trileaflet vessels for reconstruction of right ventricular outflow tract performs well in anti-regurgitation function in the short term or may be used as a replacement material for the homograft/heterograft vessel, but longer follow-up and more cases are needed.

A Recurrent Case of Constrictive Pericarditis after Pericardiectomy Using ePTFE Pericardial Substitution / 日本心臓血管外科学会雑誌

A 67-year-old man developed the recurrence of postoperative constrictive pericarditis. He had two operation histories : the one was CABG for old myocardial infarction and the other was pericardiectomy for postoperative pericarditis at 57 and 59 years old respectively. Both operations were performed in our hospital. We used an ePTFE sheet for covering the heart in the pericardiectomy. The course post operation was good, but eight years after the pericardiectomy, he had abdominal distension and leg edema. Detailed studies revealed a recurrence of constrictive pericarditis, and reoperation was performed. The re-operative finding showed thickened sclerotic tissues on both sides of an ePTFE sheet which was applied to the cardiac surface during the previous surgery. No abnormal tissue was detected where the ePTFE sheet was not applied. The ePTFE sheet and the sclerotic tissues were removed under cardiopulmonary bypass support, and then diastolic dysfunction improved dramatically. His chest was closed without applying an ePTFE sheet. His post-operative course was uneventful and he was discharged on the 20th postoperative day. The ePTFE sheet was highly suspected as a cause of the recurrent constrictive pericarditis. An ePTFE sheet-induced constrictive pericarditis should be considered as one of the postoperative complications even in the mid and long-term period. The ePTFE sheet is useful for preventing heart or vascular injury when we perform resternotomy, but in rare cases, there is some possibility of association with a risk of pericarditis.

A Case of Constrictive Pericarditis Occurring One Month after Coronary Artery Bypass Graft / 日本心臓血管外科学会雑誌

A 81-year-old man underwent CABG for angina pectoris. The grafts were all patent in postoperative coronary angiography and he was discharged on postoperative day 24. Pericardial and pleural effusion appeared in 1 month after surgery. After pericardial and pleural effusion drainage, we started steroid therapy. However, his symptoms did not improve. We performed pericardiectomy under the diagnosis of constrictive pericarditis. Diastolic dysfunction improved after the surgery, and he was discharged on postoperative day 117.

Application of expanded polytetrafluoroethylene in filling nasal base / 中华医学美学美容杂志

Objective To investigate the effect and safety of PTFE filling on correction of nasal basal treatment of midfacial sag.Methods Top of the vestibular sulcus groove was cut along the alveolar mucosa under direct maxillary periosteum,and then face inward in depression and the side line of the scope of subperiosteal separation from near to the medial nasal spine and the lateral side of pyriform aperture;range of separation was the same of both sides as marked before operation,slightly larger than the prosthesis;then the arc being carved,which was consistent with the nasal triangle expansion,was implanted into sub-periosteal site along pear-shaped arc edge of the hole placement and the prosthesis was fixed;as the appearance was satisfied,the incision was sutured.Results Clinical follow-up lasted for 6 months,and all the wound healing was well in primary intention without infection,implant exposure and other complications and facial expressions were natural.The filled results were satisfactory.Conclusions For correction of midfacial depression without need of osteotomy,nasal application of PTFE filling is simple with good efficacy and it is worth promoting.

Surface Coating of Polytetrafluoroethylene with Extracellular Matrix and Anti-CD34 Antibodies Facilitates Endothelialization and Inhibits Platelet Adhesion Under Sheer Stress

Expanded polytetrafluoroethylene (ePTFE) polymers do not support endothelialization because of nonconductive characteristics towards cellular attachment. Inner surface modification of the grafts can improve endothelialization and increase the long-term patency rate of the ePTFE vascular grafts. Here we reported a method of inner-surface modification of ePTFE vascular graft with extracellular matrix (ECM) and CD34 monoclonal antibodies (CD34 mAb) to stimulate the adhesion and proliferation of circulating endothelial progenitor cells on ePTFE graft to enhance graft endothelialization. The inner surface of ECM-coated ePTFE grafts were linked with CD34 mAb in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) solution and the physicochemical properties, surface morphology, biocompatibility, and hemocompatibility of the grafts were studied. The hydrophilicity of CD34 mAb-coated graft inner surface was significantly improved. Fourier transform infrared spectroscopy analysis confirmed ECM and CD34 mAb cross-linking in the ePTFE vascular grafts with our method. Scanning electron microscopy analysis showed protein layer covering uniformly on the inner surface of the modified grafts. The cell-counting kit-8 (CCK-8) assay confirmed that the modified graft has no obvious cytotoxicity. The modified graft showed a low hemolytic rate (0.9%) in the direct contact hemolysis test, suggesting the modification improved hemocompatibility of biopolymers. The modification also decreased adhesion of platelets, while significantly increased the adhesion of endothelial cells on the grafts. We conclude that our method enables ePTFE polymers modification with ECM and CD34 mAb, facilitates endothelialization, and inhibits platelet adhesion on the grafts, thus may increase the long-term patency rate of the prosthetic bypass grafts.

A Case of a Right Ventricular Mass after Surgery for Tetralogy of Fallot Suspected to Be Caused by a Folded Expanded Polytetrafluoroethylene Pericardial Sheet / 日本心臓血管外科学会雑誌

A 28-year-old man visited the emergency department of our hospital with a chief complaint of palpitation and chest pain. The patient had undergone 4 operations at other hospitals for tetralogy of Fallot (TOF), left pulmonary atresia, an aberrant right coronary artery, and a right aortic arch. As a result of thorough investigations, we suspected that the cause of the patient's symptoms was an excess of the right ventricular pressure over the left ventricular pressure, which was caused by right ventricular compression resulted from an abnormal mass on the anterior surface of the right ventricle, and by pulmonary stenosis (PS) associated with right ventricular outflow tract stenosis (RVOTS). Excision of the mass, right ventricular outflow restoration (RVOTR), and pulmonary valve replacement (PVR) were indicated. The mass on the anterior surface of the right ventricular was found to have been caused by retention of serous fluid in the interstice formed by a folded expanded polytetrafluoroethylene (ePTFE) pericardial sheet. An ePTFE pericardial sheet, which is used to supplement the pericardium, has been reported to have advantages with respect to prevention of adhesion, denaturation of pericardial substitutes, and inflammatory thickening and adhesion of the epicardium, compared with other materials used as pericardial substitutes. However, epicardial thickening has been noted with the use of ePTFE pericardial sheets, and hence, its use is currently avoided in many cases. This case presents an extremely rare pathology in which the inflammatory reaction of the epicardium caused by an ePTFE pericardial sheet is suspected to have caused serous components to become tightly encapsulated in the interstice formed by the folded patch ; no definite cause was identified. Thus far, no other such case has been reported, and ePTFE pericardial sheets should be used with caution.

The Clinical Effect of Micro-Multiporous Expanded Polytetrafluoroethylene Insertion for Recurrent Pterygium

PURPOSE: To investigate the clinical effect of micro-multiporous e-PTFE insertion for severe recurrent pterygium with symblepharon. METHODS: The present study included a total of 13 cases of recurrent pterygium associated with symblepharon, motility restriction and diplopia which had undergone micro-multiporous e-PTFE insertion after pterygium excision, 0.02% mitomycin C application, human amniotic membrane transplantation (AMT) and/or conjunctivo-limbal autograft (CLAU) between September 2010 and February 2011. One month after surgery, the inserted e-PTFE was removed. Recurrence of pterygium and symblepharon, motility restriction, diplopia and injection of ocular surface were evaluated for 11.92 +/- 1.32 months of mean follow-up period. RESULTS: Pterygial recurrence was not observed in 12 out of 13 eyes, and the 1 eye which recurred showed conjunctival recurrence. No postoperative symblepharon recurrence was observed in any of the 13 eyes. Diplopia and motility restriction disappeared in 11 out of 13 eyes, and were improved in the other 2 eyes. VAS (Visual Analogue Scale) injection scores in the wound site decreased after surgery in all patients. CONCLUSIONS: Micro-multiporous e-PTFE insertion combined with mitomycin C application, AMT and CLAU can be a useful surgical method to lower the postoperative recurrence rate and to improve the pterygium-related symptoms in severe recurrent pterygium.

Autologous nasal septal cartilage combined with expanded-polytetrafluoroethylene in the secondary nasal deformity correction surgery of postoperative cleft lip / 中华医学美学美容杂志

Objective To correct the nasal deformities of cleft lip by expanded-polytetrafluoroe thylene (e-PTFE) combined with autologous nasal septal cartilage.Methods e-PTFE was placed nearby verge of anterior nasal aperture to raise the fundament of nose.Autologous nasal septal cartilage was harvested and combined with e-PTFE to form a sandwich structure.Nasal tip and collapsed nasaI alar were repaired by this method.Results Fifty cases were treated by this method and 42 cases were followed up for about one year.The results were satisfying.The contour of the nose was similar to normal.Only 3 cases were relapsed after one year.Conclusions e-PTFE combined with autologous nasal septal cartilage is an ideal method to correct nasal deformities of cleft lip.

Guided bone regeneration using two types of non-resorbable barrier membranes

INTRODUCTION: Guided bone regeneration (GBR) is a common procedure for the treatment of bone defects and bone augmentation. The non-resorbable barriers are well-documented barriers for GBR because of their stability and malleability. However, few GBR studies have focused on the different types of non-resorbable barriers. Therefore, this study examined the clinical results of different non-resorbable barriers for GBR; expanded polytetrafluoroethylene (e-PTFE) (TR-Gore Tex, Flagstaff, AZ, USA), and high-density polytetrafluoroethylene (d-PTFE) (Cytoplast membrane, Oraltronics, Bremen, Germany). MATERIALS AND METHODS: The analysis was performed on patients treated with GBR and implant placement from January 2007 to October 2007 in the department of the Seoul National University Bundang Hospital. The patients were divided into two groups based on the type of non-resorbable barrier used, and the amount of bone regeneration, marginal bone resorption after prosthetics, implant survival rate and surgical complication in both groups were evaluated. RESULTS: The implants in both groups showed high survival rates, and the implant-supported prostheses functioned stably during the follow-up period. During the second surgery of the implant, all horizontal defects were filled with new bone, and there was no significant difference in the amount of vertical bone defect. CONCLUSION: In bone defect areas, GBR with non-resorbable barriers can produce favorable results with adequate postoperative management. There was no significant difference in bone regeneration between e-PTFE and d-PTFE.

Two Cases of Left Ventricular Outflow Tract Obstruction after Rastelli Type Operation for Cardiac Anomalies Associated with Transposed Aorta from the Right Ventricle / 日本心臓血管外科学会雑誌

Intracardiac repair for cardiac anomalies associated with a transposed aorta from the right ventricle is a technically demanding operation. We present two cases of left ventricular outflow tract (LVOT) obstruction after the use of an ePTFE flat patch to reconstruct the LVOT. Case 1 : A 10-year-old boy had undergone the Rastelli operation, VSD enlargement, and intraventricular re-routing using an ePTFE flat patch for repair of the DORV with noncommitted VSD and pulmonary stenosis at the age of 5. Five years later, catheter examination revealed severe LVOT obstruction. Intraventricular re-routing using a part of the ePTFE graft concomitant with re-replacement of an extracardiac conduit was successfully performed. Case 2 : A 13-year-old girl had undergone a double-switch operation (Senning operation, the Rastelli operation, and intraventricular re-routing by the use of an ePTFE flat patch) for the repair of corrected TGA, PA and VSD at the age of 7. Six years later, catheter examination revealed severe LVOT obstruction. Intraventricular re-routing using part of the ePTFE graft concomitant with re-replacement of an extracardiac conduit was successfully performed. We consider that the use of a flat patch for reconstruction of a left ventricular out flow tract in cases with transposition of the aorta from the right ventricle involves a risk of future development of LVOT obstruction.

ePTFE in the secondary nasal deformity correction surgery of postoperative cleft lip / 实用口腔医学杂志

Objective: To investigate a better method to correct the secondary nasal deformity of postoperative cleft lip, by using the expanded polytetrafluoroethylene (ePTFE) to reinforce the intensity of the nasal alar cartilage. Methods: ePTFE was used to reinforce the intensity of the cleft side of nasal alar cartilage and corrected 120 cases of the secondary nasal deformities of postoperative cleft lip. Results: All the 120 cases of patients with nasal alar tumbling showed significant improvements. In follow-up, 76 cases of patients' wound healed well. No rejection in all cases. Conclusion: The ePTFE is an ideal implant material to correct the secondary nasal deformities of postoperative cleft lip.

Effect of MBCP block as carrier of rhBMP-2 in combination with ePTFE membrane on bone formation in rat calvarial defects / 대한치주과학회지

PURPOSE: The carrier used as delivery agent for bone morphogenetic proteins(BMPs) should also act as a scaffold for new bone formation. Moreover, bone formation should be predictable in terms of the volume and shape. This study examined the osteogenic effect of macroporous biphasic calcium phosphate (MBCP) block combined with ePTFE membrane as a carrier for recombinant human bone morphogenetic proteins (rhBMP-2). In addition, the additive effect of ePTFE membrane on bone formation was evaluated. MATERIALS AND METHODS: Eight-millimeter critical sized calvarial defects were created surgically in 28 male Sprague-Dawley rats. The animals were divided into 2 groups containing 14 animals each. The defects were treated with either rhBMP-2/MBCP block (rhBMP-2/MBCP group) or rhBMP-2/MBCP block/ePTFE membrane (rhBMP-2/MBCP/ePTFE group). A disc-shaped MBCP block (3 mm height and 8 mm diameter) was used as the carrier for the rhBMP-2 and ePTFE membrane was used to cover the rhBMP-2/MBCP block. The histologic and histometric parameters were used to evaluate the defects after 2- or 8-week healing period (7 animals/group/healing interval). RESULTS: The level of bone formation in the defects of both groups was significantly higher at 8 weeks than that at 2 weeks (P < 0.05). The ePTFE membrane has no additional effect compared with the rhBMP-2/MBCP block only. However, at 8 weeks, rhBMP-2/MBCP/ePTFE group showed more even bone formation on the top of the MBCP block than the rhBMP-2/MBCP group. CONCLUSION: These results suggest that the ePTFE membrane has no additive effect on bone formation when a MBCP block is used as a carrier for rhBMP-2.

The effect of polyphosphate on exophytic bone formation / 대한치주과학회지

PURPOSE: It has been shown that the inorganic polyphosphate is effective for the regeneration of bones through the preliminary animal test of rabbits. The most effective concentration of the polyphosphate, however, is not known yet. Moreover, the effectiveness of carriers inside human body is not confirmed.. MATERIALS AND METHODS: In this study, we examined the effect of the concentration of the inorganic polyphosphate on the process of the bone regeneration using the 6 weeks old rabbits with the weight of 2.0 kg in average. We performed the experiment using TR-ePTFE membrane(membrane) filled with collagen immersed in 4%, 8% of inorganic polyphosphate, respectively, following removal of the proper sized cortical bones from the rabbit calvaria. The experimental results were compared with the one of the following four groups: The negative control group for membrane only, the positive control group for membrane filled with collagen, the first experimental group for membrane filled with collagen immersed in 4% of inorganic polyphosphate, and the second experimental group for membrane filled with collagen immerse in 8% of inorganic polyphosphate. The fragments of the tissue with membrane obtained from each group of the sacrificed rabbits for 8 or 16 weeks sustained after surgery were then prestained by the Hematoxylin-Eosin stain and coated by resin to form non-decalcified specimens for the histologic examination and analysis. New bone formation was assessed by histomorphometric and statistical analysis. RESULTS: 1. All groups have shown better bone regeneration at 16weeks than 8weeks. 2. Negative control group has shown more bone regeneration relative to the other groups at 8 and 16 weeks. 3. All experimental groups have shown better bone regeneration relative to positive control group. 4. At 16 weeks, the first experimental group has shown more bone regeneration compared to the second experimental group. Exophytic bone formation is not good at the first and the second experimental groups compared with negative control group. But, the use of 4% inorganic polyphosphate was more effective to bone formation than the use of 8% inorganic polyphosphate. CONCLUSION: With above results, it is suggested the use of inorganic polyphosphate with vehicle under TR-ePTFE membrane.

The effect of human demineralized freeze-dried xenograft on vertical bone formation in beagle dogs / 대한치주과학회지

PURPOSE: The purpose of this study was to evaluate exophytically vertical bone formation in the mandibular premolar area of beagle dogs by the concept of guided bone regeneration with a titanium reinforced e-PTFE membrane combined with human demineralized freeze-dried bone. MATERIALS AND METHODS: Four one-year old beagle dogs were divided into control and experimental group. All mandibular premolars were extracted and surgical vertical defects of 5 mm in height were created in the extracted sockets. At 8 weeks after the extraction, TR e-PTFE membrane sized with 8 mm in length, 5 mm in width, and 4 mm in height was placed on the decorticated mandible, fixed with metal pins and covered with full-thickness flap and assigned as control group. In experimental group, decorticated mandibule was treated with TR e-PTFE membrane and human demineralized freeze-dried bone. The animals were sacrificed at 16 weeks after the regenerative surgery, and new bone formation was assessed by histomorphometric as well as statistical analysis. RESULTS: Average of new bone formation was 38% in the control group, whereas was 25% in the experimental group (p<0.05). Average of connective tissue formation was 42% in the experimental group, whereas was 30% in the control group (p<0.05). The lamellar bone formation with haversian canals was observed in the both groups. In the experimental group, the particles of human demineralized freeze-dried bone were observed after 16 weeks and complete resorption of graft was not observed. CONCLUSION: On the basis of these findings, we conclude that titanium reinforced e-PTFE membrane may be used alone for vertical guided bone regeneration, but demineralized freeze-dried bone has no additional effect on vertical guided bone regeneration.

Histomorphometric study on effect of the polyphosphate for bone regeneration / 대한치주과학회지

In this study, author examined the effect of the concentration of the inorganic polyphosphate on the process of the bone regeneration by using the 6 weeks old rabbit with the weight of 2.0kg in average. we performed the experiment by using TR-ePTFE membrane filled with collagen immersed with 1%, 2%, and 4% of inorganic polyphosphate, respectively, after removing the proper sized cortical bones from the calvaria of rabbit. The experimental results were compared with the one of the following four groups: The control group for membrane only, experimental group I for membrane filled with collagen immersed with 1% of inorganic polyphosphate, experimental group II for membrane filled with collagen immerse with 2% of inorganic polyphosphate, experimental group III for membrane filled with collagen immersed with 4% of inorganic polyphosphate. The fragments of the tissue with membrane were obtained from each group of the sacrificed rabbits for 4 or 8 weeks sustained after surgery, were then prestained and coated. New bone formation was assessed by histomorphometric and statistical analysis. We may draw the conclusions from these experiments as following: 1. Collagen was an excellent carrier with a minimal inflammatory reaction and sustaining the form. 2. The sample of the 8th week group has shown the best bone regeneration compared with the cases of all groups including the control group. 3. The samples of collagen immersed with 2% and 4% of inorganic polyphosphate have shown more bone regeneration relative to the sample of the 1% inorganic polyphosphate. 4. The new bone regeneration was shown actively in the group for membrane filled with collagen immersed with 4% of inorganic polyphosphate. With above results, it is strongly suggested the use of inorganic polyphosphate with vehicle under TR-ePTFE membrane.

Histologic evaluation of the regenerated bone using bone graft materials / 대한치주과학회지

This study was performed to evaluate the effect of bone graft materials including demineralized freeze-dried bone, freeze-dried bone, deproteinized bovine bone on space-making capacity and bone formation in guided bone regeneration with titanium reinforced ePTFE membrane(TR-ePTFE). Adult male rabbits(mean BW 2kg) were used in this study. Intramarrow penetration defects were surgically created with round bur on calvaria of rabbits. TR-ePTFE membrane was adapted to calvarial defect and bone graft materials were placed. Animals were sacrificed at 2, 8, 12 weeks after surgery. Non-decalcified specimens were processed for histologic analysis and prepared with Villaneuva bone stain. The results of this study were as follows: 1. TR-ePTFE membrane was biocompatible and capable of maintaining the space-making. 2. Tissue integration was not good at TR-ePTFE membrane. Fixation was not enough. so, wound stabilization was not good. 3. In animals using deproteinized bovine bone, demineralized freeze-dried bone, bone formation was little. 4. In animals using freeze-dried bone, bone formation was better. Within the above results, bone formation may be inhibited when wound stabilizafion was not good.

Clinical and histopathological study using platelet-rich plasma and bone graft in the localized alveolar bone defects / 대한치주과학회지

Alveolar ridge defects may limit or restrict placement of implants. The purpose of this study was to evaluate clinical and histopathologic results which occur following guided bone regeneration using platelet-rich plasma, bovine bone powder and e-PTFE membrane in the localized alveolar bone defects. Ten patients who required guided bone regeneration in implant placemnet, were slelected. Alveolar crest height and width were measured at baseline and, afer 2nd surgery 5 months later At 5 months , we obtained histopathological results as follows: 1. Alveolar crest height was an average of 8.20+/-3.74 mm preoperatively and decreased to an average of 7.40 +/-1.84 mm postoperatively. There was no significant difference. 2. Alveolar crest width was an average of 4.25+/-2.03 mm preoperatively and significantly increased to an average of 7.20+/-2.44 mm postoperatively (P<0.01) 3. The change of Alveolar crest height and width were 0.80+/-1.40 mm, 2.95+/-1.09 mm 4. Histopathological evaluations revealed new bone formation with graft material and laminated bone containing the presence of osteocyte-like cell In conclusion, guided bone regeneration using platelet-rich plasma, bovine bone powder and e-PTFE membrane would provide a viable therapeutic alternative for implant placement in the localized alveolar defect or implant failure