Graft Suture Research Articles

An In Vivo Biomechanical Study on the Tension–Versus–Knee Flexion Angle Curves of 2 Grafts in Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction: Effects of Initial Tension and Internal Tibial Rotation

The purposes of this study were to determine the relation between the graft tension and the knee flexion angle in the anteromedial (AM) and posterolateral (PL) bundles of a clinically simulated anatomic double-bundle anterior cruciate ligament (ACL) reconstruction procedure and to clarify the effect of initial tension on the tension-versus-flexion curve of each graft, as well as the effect of internal rotation of the tibia on the tension of the 2 grafts. During ACL reconstruction in 30 patients, 2 suture anchors with a No. 1 polyester suture were firmly screwed into the center of the anatomic attachment of the AM and PL bundles on the femur, respectively, and each graft tension was measured with a strain gauge-type tensiometer attached at the end of the suture under 2 conditions of initial tension. The averaged tension-versus-flexion curves were significantly different between the AM and PL grafts under each initial tension condition (P < .0001). The initial tension applied at 30 degrees of knee flexion significantly affected the absolute values of each graft tension at each knee flexion angle (P < .0001) but did not significantly affect the tension-versus-flexion curve pattern of each graft. The maximal internal rotation of the tibia significantly increased the tension on both the AM and PL grafts at knee flexion angles of less than 60 degrees under each initial tension condition (P < .0001). The tension-versus-flexion curves of the 2 sutures, which mimicked the AM and PL grafts reconstructed clinically with the anatomic double-bundle ACL reconstruction procedure, were significantly different in the tension values. Differences in initial tension applied to the 2 grafts significantly affected the absolute values of each graft tension at each knee flexion angle but did not significantly affect the tension-versus-flexion curve pattern. The maximal internal rotation of the tibia significantly increased the tension on both the AM and PL suture grafts at knee flexion angles of less than 60 degrees . Level I, testing of previously developed diagnostic criteria in series of consecutive patients with universally applied gold standard.

Comparison of Initial Fixation Properties of Sutured and Nonsutured Soft Tissue Anterior Cruciate Ligament Grafts With Femoral Cross-Pin Fixation

To determine whether or not suturing a soft tissue graft in a whipstitch fashion is an essential procedure in order to ensure sufficient initial fixation strength of the cross-pin fixation technique in anterior cruciate ligament reconstruction. Porcine digital extensor tendons were used as 4-stranded soft tissue grafts. Specimens were fixated within 52 porcine femoral bone tunnels using a cross-pin fixation technique (RigidFix; Ethicon, Norderstedt, Germany). In group I (n = 28), the looped-over part of the grafts was sutured using a whipstitch technique; in group II (n = 28) the grafts were not sutured. Initial fixation properties were determined using either a single cycle load to failure protocol or a dynamic loading protocol, submitting the graft to 1,000 cycles of flexion-extension loading between 0 degrees and 90 degrees , followed by ultimate loading to failure. The graft-pin interaction and the graft-tunnel interface was histomorphologically visualized in unloaded and dynamically loaded grafts. After dynamic loading, the residual displacement in sutured grafts was lower when compared to nonsutured grafts. The ultimate failure loads were significantly lower in nonsutured grafts when compared to sutured grafts after dynamic loading. The histomorphologic analysis demonstrated intratunnel displacement of nonsutured grafts after dynamic loading, while sutured grafts remained in situ. In cases where the cross-pins had not threaded the tendon loops, sutured grafts provided higher fixation strength and less graft displacement. The results of the present study suggest that suturing the looped-over portion of a quadruple tendon graft provides superior biomechanical graft fixation properties when compared to nonsutured grafts when using the femoral cross-pin fixation technique. Suturing the hamstring tendon graft in a whipstitch fashion is recommended for the femoral cross-pin fixation of an anterior cruciate ligament graft.

The Endoscope as an Adjunct to Correction of Nipple Inversion Deformity

Correction of the inverted nipple requires release of constricting fibrous tissue and suspension of the nipple. Despite the simplicity, lasting repair is often difficult to achieve, as is the ability to assure preservation of functioning lactiferous ducts during release. Since 2002, the authors have used the endoscope to guide selective division of retracted fibrous bands, followed by the use of a dermal fat graft and purse-string suture to the base to achieve stable nipple projection. In this series of 28 nipples of 15 patients, the patients were followed up for a mean period of 14 months (range, 6 to 26 months). The outcome was judged to be excellent in 23 nipples (82 percent) and fair in five (18 percent). There were no instances of any changes in sensitivity of the nipple-areola complex. Four patients experienced lactation afterward. The endoscope clearly delineated band from duct. The authors' technique was able to maintain excellent projection, with preservation of breast feeding as well as normal breast sensation, except in grade IIIB inverted nipples.

Lateral canthal anchoring for correction of lower eyelid retraction

目的 探讨外眦锚着术在睑袋术后并发下睑退缩修复中的应用,寻找一种理想可靠的修复方法.方法 应用外眦锚着术修复下睑退缩126例(207只眼),对其中20例(33只眼)单纯施行经外眦眦固定术,以缩紧外眦腱;35例(57只眼)施行3 mm睑板条外眦成形术;26例(45只眼)行经外眦眦固定术,同时行Hamra释放弓状缘和保留眶脂肪的下睑成形术;45例(72只眼)行睑板条技术,同时行Hamra术.结果 术后75例(123只眼)得到6～12个月的随访,平均随防时间8个月.除1例(1只眼)较重的下睑退缩矫正不全外,其余美容外观和功能均获得满意效果.没有明显的并发症发生,仅有1例发生轻微的缝线刺激反应,在随访期间恢复正常.结论 外眦锚着术在轻到中、重度的下睑退缩修复中是一项有效方法,既能达到改善眼睑外观,又能恢复眼睑功能的目的,并发症少,患者满意。

Intraoperative Anterior Cruciate Ligament Graft Contamination

Abstract Intraoperative anterior cruciate ligament graft contamination is a rare but potentially devastating occurrence for any surgeon to encounter. Most instances in our experience have happened when a surgeon first enters practice or is operating in a new environment with new staff. Based on the currently available literature and the senior author’s personal experience with 3 cases, intraoperative cleansing of the graft followed by implantation is a reasonable option. The protocol used successfully in these 3 cases includes getting the graft off of the floor immediately, removing any suture material in the graft, cleansing the graft for 15 to 30 minutes each in chlorohexidine and triple antibiotic solution, followed by a normal saline rinse. All graft sutures should then be replaced. The graft should then be resized and the tibial and femoral tunnels adjusted if needed. After implantation of the graft, additional intraoperative and postoperative intravenous antibiotic and/or oral antibiotic administration is also recommended for the first 1 to 2 weeks. Close clinical follow-up is also very important the first 6 weeks postoperatively and should include candid communication with the patient and family.

Femoral Interference Screw Placement Through the Tibial Tunnel: A Novel Method Without Graft Damage

Abstract A frequently encountered problem in endoscopic 1-incision anterior cruciate ligament (ACL) reconstruction is the difficulty involved in accurately inserting the femoral interference screw without significant and undesirable divergence between the screw and the graft when a femoral interference screw is fixed through the anteromedial portal. To minimize divergence, the authors demonstrated a modified, easy, and reproducible procedure that can be performed without causing graft injury or requiring special instrumentation. A ligament reconstruction route is created with the use of an ACL guide system. Lead graft sutures are pulled through the anteromedial portal by way of the femoral tunnel and out the anterolateral thigh first. The tendon graft is then inserted through the anteromedial portal and up into the femoral tunnel. A guidewire is introduced through the tibial tunnel into the femoral tunnel. An appropriately sized BioScrew (Linvatec, Largo, FL) is inserted, with the use of a guidewire inside the screw, through the tibial tunnel into the femoral tunnel. The graft is then retrieved through the anteromedial portal and is inserted through the tibial tunnel. Finally, the tendon graft in the tibial tunnel is similarly fixed with a BioScrew of the same size. Moreover, this novel approach is feasible for all tendon grafts (bone–patellar tendon–bone grafts, quadriceps tendon–patellar bone grafts, and hamstring tendon grafts).

Tendon Augmentation Grafts: Biomechanical Failure Loads and Failure Patterns

The purpose of this study was to determine the load to failure strengths and modes of failure of various commercially available tendon augmentation xenografts and allografts. Experimental laboratory study. GraftJacket (Wright Medical Technology, Arlington, TN), CuffPatch (Arthrotek, Warsaw, IN), Restore (Depuy, Warsaw, IN), Permacol (Tissue Science Laboratories, Covington, GA; licensed to Zimmer, Warsaw, IN), and TissueMend (TEI Biosciences, Boston, MA; licensed to Stryker Howmedica Osteonics, Kalamazoo, MI) measuring 2 x 5 cm were hydrated according to manufacturers guidelines, a horizontal mattress stitch 5-mm wide was placed 5 mm from the narrow edge of the graft. Tensile loads to failure were applied on the suture while an Instron machine held the graft material and mean loads to failure of the suture graft construct were obtained and modes of graft failure noted. The mean loads to failure were obtained: GraftJacket thin (157 N), GraftJacket MaxForce (182 N), GraftJacket Extreme (229 N), CuffPatch (32 N), Restore (38 N), Permacol (128 N), and TissueMend (70 to 76 N). Failure occurred principally by suture pull-through in all specimens and patterns tended to vary by implant type. CuffPatch and TissueMend tended to fail by isthmus pullout, whereas Restore and Graft jacket failed by end pullout. The tissues were statistically stratified into four groups depending on the material. Human skin (GraftJacket) was the strongest followed by porcine skin (Permacol) and bovine skin (TissueMend). Both in turn were stronger than the porcine small intestine submucosa (Restore and CuffPatch) (P < 0.001). Suture retention can be reliably tested with a narrow range of standard error utilizing this testing methodology. Skin has higher loads to failure than intestine submucosa. Failure modes differed significantly among the implant types, suggesting that suturing methods for each implant should be considered independently before use. These data cannot be interpreted to suggest that one graft material is clinically superior to another. Rather, each has different properties that the surgeon should recognize when considering their use. These grafts have been used as augmentations and substitutions in tendon repairs and as a material for interpositional arthroplasty. These data show that the successful use of these materials requires adequate separation of the fixation sutures and provides an understanding of how each material will fail if subjected to excessive loading during the rehabilitation period.

A New Surgical Technique for Anterior Segment Ectasia: Tectonic Lamellar Sclerokeratoplasty

A 41-year-old patient with severe anterior segment ectasia and a previous history of failed corneal graft was treated by placing a 14-mm tectonic corneoscleral allograft in the eye to support both the corneal and the scleral thinning. Nylon 10-0 interrupted sutures were used at the sclero-scleral junction. The host conjunctiva, including the limbal area, was carefully sutured to the donor limbal area. Three months postoperatively, the graft was stable with no progression of the ectasia. The suturing of a corneoscleral graft over a severely ectatic cornea may be an acceptable technique for providing tectonic tissue support and stabilizing eyes with severe anterior segment ectasia.

Prospective Evaluation of the St. Jude Medical Aortic Connector for Aortic-to-Autologous Vessel Graft Anastomoses

: Evolving technologies of proximal anastomosis devices meet the endeavor of surgeons to minimize manipulation of the ascending aorta during surgical myocardial revascularization. The objective of this study was to compare the patency rate of the saphenous vein coronary bypass grafts in which the proximal anastomoses were performed with automatic connector devices to the suture technique. : From September 2002 through July 2003, 86 patients underwent coronary artery bypass grafting with at least 1 vein graft anastomosed to the ascending aorta with the Symmetry G2 connector. Six-month clinical and angiographic follow-up, including Core-Lab quantitative coronary angiography (QCA) and corrected TIMI frame count (CTFC), was performed. : Eighty patients had at least 1 connector successfully implanted. Freedom from MACE (cardiac mortality myocardial infarction and target vessel reintervention) was 72/80 (90%). Six patients underwent a target vessel reintervention on the connector grafts. Six-month (mean 193 ± 36 days) angiography patency rates for the connector grafts were 72/81 (88.89%), 37/40 (92.5%) in sutured grafts, and 60/62 (96.8%) in arterial grafts. By QCA, 64/65 (98.5%) patent connector-grafts were free from more than 50% stenosis (1 connector-graft with a 51% stenosis). CTFC showed 65/65 (100%) patent connector-grafts with nonrestrictive flow. : Saphenous vein grafts anastomosed to the aorta with the Symmetry G2 connector have early and midterm patency rates comparable to the conventional sutured anastomoses. These results support the efficiency of the second generation of symmetry aortic connectors.

An Alternative Surgical Procedure for the Management of Keratoglobus

To describe an alternative surgical technique in stabilizing peripheral corneal thinning in keratoglobus corneas with severe ectasia. A 27-year-old man with keratoglobus and severe corneal ectasia in his remaining functional eye was managed by surgically placing an allograft corneoscleral ring around the limbus to support the mid-peripheral thinned cornea. Nylon 10-0 interrupted sutures were used only at the limbus. The allograft corneoscleral ring had an outer diameter of 14.5 mm and an inner opening of 7.0 mm. Conjunctiva was draped over and sutured to the donor corneoscleral ring graft. Cornea and vision are stable at 18 months' follow-up. The peripheral suturing of a corneoscleral ring graft over the periphery of the cornea maybe an acceptable technique for providing tectonic tissue support and stabilizing eyes with keratoglobus.

Morphology after synergistic terminal end-to-side nerve graft repair: Investigation in a nonhuman primate model

BACKGROUND: Functional efficacy of synergistic terminal end-to-side nerve graft repair in a median nerve defect model in nonhuman primates was recently published elsewhere. The purpose of this study was to investigate the morphology of the end-to-side repair site and the nerve graft used after synergistic terminal end-to-side nerve graft repair. METHODS: Experiments were carried out in seven adult baboons. Synergistic end-to-side nerve graft repair bridging from the terminal motor branch of deep branch of the ulnar nerve to the thenar motor branch of the median nerve was performed after transection of the median nerve at forearm level. Specimens were harvested three months after surgery. Chromotrope aniline blue was used for staining neural collagenic connective tissue. S100-antibody was used to quantify the number of Schwann cells. Axon counts were performed using NF (neurofilament) antibody staining. To enable profound morphological assessment, specimens were harvested 5 mm proximal to the end-to-side nerve graft repair site (deep branch of ulnar nerve), at the end-to-side nerve graft repair site (proximal graft), and at the distal end-to-end nerve graft suture site. The contralateral terminal deep branch of ulnar nerve served as a control. RESULTS: The area of collagenic connective tissue was 6% larger at the end-to-side repair site and 28% larger at the distal end of the nerve graft. Highest mean values were found at the distal site of the nerve graft. This was due to very strong collagenization of the nerve graft of animal number six. In other words, there was a moderate enhancement of collagenic connective tissue within the nerve graft in six animals. Schwann cell counts showed similar values within all nerve segments. There was no difference when compared to nonoperated control. The number of axons distal to the end-to-side repair site was smaller by 19% on average. Additionally, we found an average 23% decrease of axons at the end-to-end coaptation site compared to data of the deep branch of ulnar nerve. CONCLUSIONS: The results in this morphological study of synergistic end-to-side nerve graft repair at the level of very peripheral terminal motor branches in a nonhuman primate model demonstrate effective distal axonal sprouting and successful Schwann cell survival. As expected, we found a modest increase of neural collagenic connective tissue within the nerve graft in most animals (6 out of 7 animals).

Combined Hard Palate Spacer Graft, Midface Suspension, and Lateral Canthoplasty for Lower Eyelid Retraction: A Tripartite Approach

Eyelid retraction is an unfortunate consequence of cosmetic surgery, trauma, and disease states. It is frequently symptomatic and may be associated with dry eye syndrome and corneal compromise. The pathophysiology of lower eyelid retraction usually involves some degree of lateral canthal tendon laxity, middle lamella scarring, and malar descent. The authors describe for the first time a series of patients whose lid retraction was treated with a tripartite procedure that addresses all three pathophysiologic components simultaneously and rehabilitates the patients cosmetically and functionally. The authors retrospectively reviewed the records of 17 patients (24 eyelids) operated on between 1999 and 2003 by one senior surgeon. The age of the patients ranged from 26 to 77 years (mean, 50.3 years), and all presented with significant scleral show (average, 2.0 mm) and symptomatic corneal exposure from a variety of causes. Preoperatively, all patients were noted to have a combination of lower eyelid laxity, middle lamellar contracture, and malar descent. Preoperative and postoperative examinations included Shirmer's test, a measurement of scleral show, and a slit-lamp examination. Mean follow-up time was 13 months. All patients underwent a triad of hard palate spacer grafting, lateral canthal suspension, and midface elevation. All 17 patients (representing 24 retracted eyelids) had complete resolution of scleral show (2.5-mm average correction) and were uniformly satisfied with their cosmetic and functional outcome at last follow-up. Preoperative dry eye symptoms resolved in all patients in the series. There were no major complications and only two minor complications (corneal irritation from graft sutures in one patient and an oronasal palatal fistula in another), both of which resolved in the early follow-up period. The combination of hard palate spacer grafting, lateral canthoplasty, and midface suspension is an effective, aesthetic, and functional treatment for moderate to severe lower eyelid retraction resulting from multiple causes. This tripartite procedure is associated with predictable results, a low morbidity rate, and high patient satisfaction.

Missile-caused median nerve injuries: results of 81 repairs

Background Missile-caused median nerve injuries have rarely been reported in current literature. We present repair outcome for all median nerve injuries in which the median nerve was severed either by missile injury or secondarily in the subsequent resection of a neuroma in continuity. Methods Prospective study included 81 casualties with proximal, intermediate, or distal complete median nerve lesions, repaired by nerve graft or direct suture. Final outcome was defined at least 4 years postoperatively, on the basis of motor recovery, sensory recovery, neurophysiological recovery, and patient's judgment on the outcome, each estimated by 0 to 5 points and according to the total sum, as poor, insufficient, good, or excellent. The last 2 modalities were considered to be successful. Results Successful outcome was obtained in 68.7% of distal, in 33.3% of intermediate, and in 10% of proximal repairs. Average outcomes were good, insufficient, and poor, respectively ( P < .001). Nerve defect and preoperative interval were both significantly shorter on average for patients with successful outcome than for those with unsuccessful outcome ( P < .001 and P = .007, respectively), but only preoperative interval and height of repair were independent predictors for successful outcome. Age of patient, associated ulnar nerve complete lesion, and manner of repair did not influence the outcome significantly ( P > .05). Conclusions The level of repair, duration of preoperative interval, and length of nerve defect significantly influence outcome after median nerve repair, but only level of repair and duration of preoperative interval were independent predictors for successful outcome.

Comparison of Clinical Results According to Amount of Preserved Remnant in Arthroscopic ACL Reconstruction using Quadrupled Hamstring Graft

Purpose: To analyze the clinical results in an ACL reconstruction according to the amount of the tibial remnant of the ACL using a hamstring graft and looped sutures. Materials and Methods: Sixteen patients who were followed up for at least 12 months after the ACL reconstruction with four strands of a hamstring tendon using a looped suture technique were enrolled in this study. The average follow-up was 35.1 months. At the last follow-up period, the patients were evaluated using the International Knee Documentation Committee (IKDC) scale and the HSS score, Lachman test, ant. drawer test, KT-1000, one-leg hoop test and proprioceptive function test (motion and position sense). They were then divided two groups according to whether they had more or less than 30% of the ACL remaining. The final results of the two groups were statistically compared. Results: Average HSS score improved from 65.8 (preoperative) to 95.2 (last follow-up). No significant differences in functional outcome and mechanical stability were found except for proprioception. Regarding the threshold of the detection of the passive motion test at 30 degrees (p=0.030) and the reproduction of the passive positioning test at 15 degrees (p=0.032) and 30 degrees (p=0.024), the more remnant preserved group (>30%) showed better results than the less preserved group. Conclusion: Preserving the tibial remnant will preserve function of the mechanoreceptors and be helpful to the recovery of the function and healing of a graft after surgery.

Missile severances of the radial nerve. Results of 131 repairs.

Reports on missile-caused radial nerve injuries are relatively rare in current literature. We present the outcome after repair of such injuries as well as the factors influencing the result of treatment. Prospective study included 131 complete missile-caused radial nerve severances repaired with nerve graft or direct suture. Final outcome was defined 4 years postoperatively at least, on the basis of motor recovery (M), EMNG recovery (E) and patient's judgement on the quality of outcome (P). Recovery was estimated with 0-5 points and final outcome was defined according to the total sum (0-15 points) as: poor, insufficient, good or excellent. Both the good and the excellent outcomes were considered as successful, and both the poor and the insufficient outcome as unsuccessful. Excellent outcome was noted in 38.2% and good outcome in 47.3% of all patients. Average point score was 9.9 +/- 3.3 points for the whole series (domain of good outcome) and 6.6 +/- 3.0, 10.1 +/- 3.2 and 10.9 +/- 2.2 points for high, intermediate and low repairs, respectively (p<0.01). Useful motor recovery (>or =M3), good EMNG recovery (> or =E3) and affirmative patient's judgement on the outcome (> or =P3) had similar frequencies for intermediate (83.2-89.7%) and low repairs (85.7-92.8%), but for high repairs, good EMNG recovery was more frequent (70%) than were useful motor recovery and affirmative patient's judgement (40%). Successful outcome was noted in 89.3% of direct sutures and in 82.7% of nerve grafts (p>0.05). Patients with a successful outcome had a significantly shorter nerve defect (p<0.001), shorter preoperative interval (p<0.001) and younger age (p<0.05) than patients with an unsuccessful outcome. Significant deterioration of results began with defects longer than 8 cm, preoperative interval longer than 6 months and age above 40 years. The outcome is significantly worse after high radial nerve repairs than after intermediate and low repairs. The length of nerve defect, duration of preoperative interval and age of the patient also influence the repair outcome. Correlation of motor recovery with EMNG recovery and with patient's judgement on the outcome is relatively good, but depends on the level of the repair.

Transtibial tubercle fixation without hardware for anterior cruciate ligament and posterior cruciate ligament reconstruction: A new technique.

Tibial fixation with implants for both anterior and posterior cruciate ligament reconstructions (ACLR and PCLR) can be associated with a wide variety of problems. Common problems encountered include graft-tunnel mismatch when using grafts with bone blocks, graft damage or poor graft fixation using metal or absorbable implants, painful retained hardware requiring removal, and hardware interference during revision surgery. A new technique is presented using transosseous graft suture passage across the tibial tubercle followed by knot tying over a bone bridge. The technique provides a quick, simple, safe, and reproducible alternative for primary or supplemental tibial graft fixation without hardware in ACLR and PCLR.

Effect of fibrin glue derived from snake venom on the viability of autogenous split-thickness skin graft

The aim of this study was to analyze the effect of snake venom derived from fibrin glue on the viability of split-thickness skin graft. Nine crossbreed dogs were used. Full-thickness skin segments measuring 4 x 4 cm were bilaterally excised from the proximal radial area on each dog. A split-thickness skin graft was harvestedfrom left lateral thoracic area using a freehand graft knife, and was secured to the left recipient bed using several simple interrupted sutures of 3-0 nylon (sutured graft). A split-thickness skin graft was harvested from the right lateral thoracic area using a graft knife. Fibrin glue derived from snake venom was applied to the recipient bed, and 8 equidistant simple interrupted sutures of 3-0 nylon were used to secure the skin graft (glued graft). Viable and nonviable areas were traced on a transparent sheet and measured using a Nikon Photomicroscope connected to a KS-300 image analysis system. The skin graft and recipient bed were collected from three dogs at day 7, 15, and 30 postoperative. The glued grafts had statistically higher graft viability than sutured grafts. Histological examination showed that the tissue repair process in the glued grafts was more accentuated than sutured grafts. It was possible to conclude that fibrin glue derived from snake venom increased survival of autogenous split-thickness skin graft.

Long-term progression of astigmatism after penetrating keratoplasty for keratoconus: evidence of late recurrence

The authors retrospectively reviewed progression of astigmatism in 80 eyes that underwent penetrating keratoplasty for keratoconus for which a mean follow-up of 20 years (range, 15–25 years) was available. Graft size, suture technique, and time of suture removal had no significant influence on the astigmatism at the last examination. There was stabilization of keratometric astigmatism in the first 7 years after suture removal (4.05 ± 2.29 diopters (D) at year 1, 4.39 ± 2.48 D at year 7). There was a progressive increase in keratometric astigmatism beginning in the 10th year after suture removal and continuing until the last follow-up visit (5.48 ± 3.11 D at year 10, 6.43 ± 4.11 D at year 15, 7.28 ± 4.21 D at year 20, and 7.25 ± 4.27 D at year 25). There was a significant correlation between the preoperative and final axis of astigmatism (P = .0008). The major slit-lamp finding was a peripheral crescent of thinning at the graft–host junction with absence of the Bowman layer on histopathology. The authors conclude the late onset of progressive astigmatism is related to progression of keratoconus in the host cornea.—Michael D. Wagoner

Estudo da regeneração nervosa em nervos tibiais de ratos wistar utilizando o Fluoro-Gold® como marcador neuronal

Os autores estudaram em ratos a regeneração nervosa no enxerto nervoso tradicional, comparando-os com grupo controle, através da contagem no nível da medula espinhal, entre L3 e S1, de motoneurônios marcados por meio de exposição do nervo tibial ao Fluoro-Gold® (FG). No grupo controle, ambos os nervos tibiais foram expostos ao FG®, e em 48 horas, após a perfusão, os motoneurônios foram contados. No grupo experimental, foi ressecado um segmento de 8mm do nervo tibial criando uma falha segmentar. O segmento de nervo de um foi usado para reparar o lado contralateral, utilizando sutura epineural. Após quatro meses, o nervo tibial direito foi exposto ao FG após o enxerto nervoso e, o esquerdo, antes do enxerto. Os motoneurônios foram contados após a perfusão. Ambas as medulas foram cortadas em segmentos de 40mm. Para a análise estatística foram utilizados testes de Wilcoxon e Student. O grupo controle apresentou um significativo aumento de motoneurônios quando comparado ao experimental. No grupo experimental, o número de motoneurônios foi significantemente maior, quando a exposição do nervo tibial ao FG® era feita distalmente ao enxerto nervoso. O enxerto nervoso funciona como um bloqueio parcial para a migração dos axônios em regeneração.

A SOLUTION AND MAINTENANCE OF PERI-IMPLANT PROBLEM; CASE REPORT FOR 5 YEARS PERI-IMPLANT TISSUE

The overall objective of this study is to evaluate the long term results of interpositional connective tissue graft and horizontal and vertical bone augmentation in recessed area of interproximal papilla. Atrophic ridges rebuilt through GBR procedures. For this study, 2 major alterations are made in the surgical technique describes. First, the horizontal and vertical bone augmentation graft is obtained from autograft like ascending ramus or allograft with or without platelet-rich plasma and barrier membrane. Second, connective tissue for interpositional grafting is obtained from hard palate. This interpositioning graft would be success by use of pouch technique or envelope flap technique. From 1998, among over than 120 patients of implant treated. for this study, regardless of 1-staged or 2-staged surgery or type of implant surface treated, 60 implants of 18 patients which has a dissatisfaction on anterior region, food impaction on posterior region subjectively, or has a black-triangle on anterior and flattened inter-implant spaces clinically was selected. Differences of success rate between inter-dental and inter-implants depend on blood supply and distance between implants. Autografts, PRP and anorganic bovine bone Bio-Oss have been successfully employed for isolated augmentation area. It is essential to make the CT graft neovascularize to a recipient site, overcorrection of graft, immobilization of graft and tension-free suture. Based on annual measurements of gross texture, pocket probing depth, attachment level, and width of keratinized mucosa, this 5-year study indicates that interpositional CT graft when used in conjunction with appropriate bone augmentation technique, can become successfully esthetics and yield predictable maintenance results.