An experimental study on the construction of tissue engineering corneal stromal stent with Smile derived corneal stromal lens / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the feasibility of constructing corneal stromal scaffolds and the optimal preservation conditions of corneal stromal lenses obtained from the small incision lenticule extraction(Smile)surgery.<p>METHODS: Constructing a bilayer lens by adhering together two corneal stromal lenses with human fibrin sealant(FS). Human corneal fibroblasts were isolated and cultured from Smile derived corneal stromal lenses <i>in vitro</i>, and the toxicity of FS on human corneal fibroblasts was detected by MTT method. The bilayer lenses were then placed in anhydrous glycerin, sodium hyaluronate eye drops, a simulated wet room environment and fetal bovine serum groups respectively, and stored at 4℃ for 14d. The transparency, hardness and stability of the scaffolds were then compared. Afterwards, the bilayer lens scaffolds were stored in anhydrous glycerin at room temperature, 4℃ and -20℃. After 14d of preservation, the diverse effects of temperature on the transparency and hardness of the scaffolds were compared.<p>RESULTS: MTT results showed that the cells of the experimental group and the control group had similar proliferation trend within 0-72h. The cytotoxicity rating of the experimental group was 0 at 36-48h and 1 at 24h and 60-72h. The relative survival rate of the cells within 0-72h was over 90%. FS-bonded bilayer lens scaffold had a smooth surface, close bonding, good transparency and suitable hardness. After 14d of storage at 4℃, none of the nine bilayer lens scaffolds in the anhydrous glycerol group showed signs of cracking cracking after rehydration, and their transparency was good. In the sodium hyaluronate group, three of the nine scaffolds cracked and the remaining six were still intact. In the simulated wet room environment group, none of the 9 scaffolds cracked, but there were different degrees of shrinkage, their surface was rough and transparency was lower. In the fetal bovine serum group, all the 9 stents were cracked, and the single corneal stromal lens was soft and edema was serious. Out of the 15 bilayer lens scaffolds preserved in anhydrous glycerol at room temperature, 2 remained colourless and transparent, 5 slightly yellowed but still remained transparent, 8 yellowed substantially with a significant reduction in transparency. Out of the 15 bilayer lens scaffolds preserved in anhydrous glycerol at 4℃, 5 remained colourless and transparent, and 10 slightly yellowed while remaining transparent. Of the 15 bilayer lens scaffolds preserved in anhydrous glycerol at -20℃, none of the scaffolds yellowed, therefore, remaining colourless and transparent.<p>CONCLUSION: FS is a safe and non-toxic bio-gel. It can be used to glue Smile-derived corneal stromal lenses to construct corneal stromal scaffolds with good stability, high transparency and suitable hardness. Anhydrous glycerol at -20℃ is the best preservation condition for corneal stromal lens scaffolds.

A comparative study of the clinical effects of Fibrin adhesive and Calcium sulfate barrier in the treatment of mandibular class II furcations using Xenograft / 대한치주과학회지

Periodontal regeneration refers to the restoration of bone, cementum and periodontal ligament to their original levels before damage from periodontal disease process. Various surgical techniques to the promotion of periodontal regeneration have been used. Bone graft and guided tissue regeneration have used for the regeneration of furcation involvements which caused by periodontal disease. Fibrin adhesive is agents that have been shown to be effective in periodontal regeneration and biological carrier. Calcium sulfate which is one of the resorbable barrier materials has used for guided tissue regeneration. The purpose of this study was to compare the clinical effects between bone graft using fibrin adhesive and calcium sulfate barrier in the mandibular class II furcation involvement. For the study, twenty-six class II furcation involved teeth were surgically treated. 13 furcation defects(test group) were treated with bonegraft and fibrin adhesive and the others(control group) were treated with bone graft and calcium sulfate barrier. Pocket depth, clinical attachment level and gingival recession were measured at baseline, postoperative 3 and 6 months. The results of the study are as follows: 1. The change of pocket depth and clinical attachment level in both groups was decreased significantly at 3, 6 months than at baseline(p<0.05). 2. The change of gingival recession in both groups was increased significantly at 3, 6 months than at baseline(p<0.05). 3. The change of pocket depth and clinical attachment level in both groups was decreased at 3, 6 months, and the change of gingival recession in both groups was increased at 3, 6 months but there were no statistically or clinically significant differences with both groups. 4. The significant reduction of the pocket depth and clinical attachment level exhibited marked changes at 3 months in both groups. In conclusion, the results of this study suggest that there are no statistically or clinically significant differences between fibrin adhesive and calcium sulfate barrier in the treatment of class II furcations using xenograft.

Action potential differences and regeneration effect after microneural suture technique and fibrin adhesive technique in rat sciatic nerve

The purpose of this study was to compare clinical availability of fibrin adhesive technique with microneural suture technique. We applicated fibrin adhesive technique and microneural suture technique on cut sciatic nerve in rat and used to Compound muscle action potential of rat thigh muscle compartment and histologic finding for comparision of clinical availability. The results were as following. 1. Using latency and amplitude in Compound muscle action potential test, we compared microneural suture technique with fibrin adhesive technique for nerve regeneration effect. the means was slightly different between two method. but there's no statistically significant differences. 2. Histologic finding was similar in microneural suture technique and fibrin adhesive technique for regeneration of axon and myelin sheath in destruction site after nerve anastomosis. These results showed that the efficacy of fibrin adhesive technique was similar to that of conventional microneural suture technique. Moreover, fibrin adhesive technique is decreased operating time and imporved of incapability of accessment in conventional suture technique. Therefore this technique is a useful method to nerve anastomosis in nerve enervation and neurotransplantation.

A Histo-Pathological Study of Effect on Bone Regeneration with Fibrin Adhesive / 대한치주과학회지

Several effective treatment methods and materials have been developed for the treatment of furcation involvement. Currently, the combination of guided tissue regeneration (GTR) and bone grafts is the most commonly prescribed method of treating furcation involved defects. But because these cases often present with poor accessibility, placement of the membrane may be difficult and consequently, clinically impractical. In this study, the alveolar bone healing patterns of adult beagle dogs presenting with alveolar bone destruction treated by one of two methods - treatment using solely bone aIlografts (BBP(R)), or treatment using bone allografts (BBP(R)) stabilized by a fibrin adhesive - were comp ared. The effects of the fibrin adhesive on the initial stabilization of the newly formed bone, subsequent regeneration of bone, and the feasibility of the clinical application of the fibrin adhesive were analyzed. The results of the study were as follows: 1. Clinical signs of inflammation at the 4-8 week interval were not observed: but signs of mild inflammation were histologically observed at the 4-week interval. 2. Allografts stabilized by fibrin adhesive showed good bone formation, whereas defects treated with only the allograft material showed incomplete alveolar bone regeneration. 3. Allografts stabilized by fibrin adhesive showed a decrease in the amount old bone with a concurrent increase in the formation of new lamellar bone four weeks post-op, whereas defects treated with only the allograft material showed no new lamellar bone formation at the same interval. 4. In detects treated with only the allograft material, the defective area was filled with connective tissue 8- weeks post-op, whereas fibrin adhesive stabilized allografts showed viable connections between the original bone and the newly formed bone, in addition to neovascularization 8-weeks post-op. The results of this study show that concurrent use of fibrin adhesive materials can stabilize the allograft material and aid in new bone formation Although the stability of fibrin adhesives fall short of the results achievable by GTR membranes, in cases presenting with poor accessibility that contraindicate the use of membranes, fibrin adhesive materials provide a viable and effective alternative to graft stabilization and new bone formation.

Effect of fibrin adhesive on healing of full-thickness wounds in the rat's hard palate

Use biologic fibrin adhesive in otologic surgery: compared with ammonium sulfate fibrin adhesive and tissell® / 영남의대학술지

Successful middle ear surgery requires the availability of al safe, effective bonding material. Side effect caused by synthetic materials have led to the use of biologic adhesive, However, they carry the risk of transmission of infectious diseases if they are prepared from pooled human blood. The adhesive strength of ammonium sulfate fibrin adhesive produce an adhesive strength that is half that of the homologous commercial product. It is, however, good enough for use in several otolaryngological operations, tympanoplasty, facial nerve repair, reconstruction of ossicles. Reconstruction of posterior wall of ear canal and obliteration of frontal sinus and mastoid antrum using bone dust.

Neurosurgical application of fibrin adhesive

We have tried fibrin adhesive, which mimics the end stage of plasmatic coagulation, in 26 patients with various neurosurgical problems such as: repair of cerebrospinal fluid (CSF) leaks, sealing of the vascular anastomosis sites, reinforcements of aneurysmal clippings, and hemostasis after resection of brain tumors. Presented in this report are 11 intracranial aneurysms, 11 brain tumors, 2 lipomyelo-meningoceles, and one each of cerebral arteriovenous malformation and torn dura resulting from a mastoidectomy. Procedures which seemed to be impossible or very difficult by conventional neurosurgical techniques could be accomplished in all cases without any complication. Our experience with fibrin adhesive suggests that it is a valuable adjuvant to various microneurosurgical procedures, and it may be potentially useful for protection of major cerebral veins and venous sinuses during cerebral retraction.

Experimental Studies of the Fibrin-Adhesive-System in Osteochondral Fractures / 대한정형외과학회잡지

A new fibrinogen system, consisting of highly concentrated fibrinogen and thrombin, is going to be applied in many clinical fields. Especially in injuries of the cartilagenous joint surface as chondral or osteochondral fractures, replantation of the fragments must be considered mandarory in order to preserve joint congruence and to prevent further destruction of the articular cartilage. The authors have an encouraging results by using this fibrin adhesive system (F.A.S.) in the experimental works.