Simplified Free Gingival Graft Around Implants Using Medical Grade Tissue Cyanoacrylate: A Case Series Report.

The free gingival graft (FGG) procedure using suturing techniques has been widely utilized to effectively increase the amount of attached keratinized gingiva. However, conventional suturing procedures are time-consuming and technique-sensitive. Simplified FGG procedure around teeth and dental implants using medical grade tissue adhesive (cyanoacrylate) is known to overcome drawbacks of traditional suture techniques. However, the clinical application of cyanoacrylate as a means of stabilizing the graft has not been a common practice. The aim of this report demonstrates simplified FGG procedures around dental implants using cyanoacrylate with follow-up results.

The Effect of Three Surgical Therapies to Increase Keratinized Mucosa Surrounding Dental Implants with Peri-Implantitis: A Pilot Study.

Background and Objectives: The purpose of this pilot study was to evaluate the clinical outcomes of three different methods for increasing the keratinized mucosa (KM) surrounding dental implants with peri-implantitis. Materials and methods: Twenty implant sites with peri-implantitis were divided into: (1) porcine collagen matrix (CM) group: seven implant sites; (2) apically positioned flap (APF) group: eight implant sites; and (3) free gingival graft (FGG) group: five implant sites. The KM width and clinical parameters (probing pocket depth (PPD) and bleeding on probing (BOP)) were measured at time points: before surgery (T0) and 30 (T1), 60 (T2), 90 (T3), and 180 (T4) days after surgery. Results: Regarding KM width, all the groups had significant differences for increasing horizontal and vertical KM width. The CM and FGG groups had greater KM than the APF group. There was a decrease in PPD in all three groups. APF and FGG showed significant differences in PPD at T1 and T2 compared to T0. Only the FGG group showed a significant difference in PPD at T3 and T4 compared with that at T0. BOP values were also reduced in all the groups at T1-T4 compared to T0. The APF and FGG groups showed a significant decrease in BOP. Conclusions: Three surgical therapies presented favorable results for increasing the KM surrounding implants. Compared with the FGG group, the CM showed similar results in increasing the KM around the dental implants with peri-implantitis.

Evaluating Change of Marginal Bone Height with Cone-Beam Computed Tomography Following Surgical Treatment with Guided Tissue Regeneration (Bone Grafting) or Access Flap Alone: A Retrospective Study.

Background and Objectives: This study aimed to evaluate the change of bone height following treatment of human intrabony defects with guided tissue regeneration (GTR) with bone grafting or access flap alone by cone-beam computed tomography (CBCT) scan. Materials and methods: This study was conducted as a retrospective longitudinal study. In this study, a total of 2281 teeth sites were included: the GTR group had 1210 sites, and the Flap group had 1071 sites. In the GTR group, demineralized freeze-dried bone (DFDBA) particles in combination with resorbable collagen membrane were used. No regenerative material was applied to the Flap group. CBCT images were taken twice at baseline and at least 2.5 months postoperatively. Bone heights were measured using software on CBCT images. Results: The bony change between the GTR and Flap groups was significantly different (p = 0.00001). Both males and females in the GTR group had smaller bone loss than in the Flap group. In age groups, significant differences of bony height between the GTR and Flap groups were observed in the subgroups consisting of those 29-45 and 46-53 years old. The non-smoking subjects in the GTR group had higher bone heights than those in the Flap group. In the absence of systemic disease and medicine, bone formation was higher in the GTR group than in the Flap group. In terms of oral position, the #14-17, #34-37, and #44-47 subgroups of the GTR group showed higher levels of bone heights than those of the Flap group. Conclusions. The results of this study indicated that the GTR procedure offers the additional benefit of higher bone heights than the Flap procedure does.

Protein Recognition by Phase Transition of Aptamer-Linked Polythiophene Single Nanowire.

A novel protein recognition platform is developed using aptamer-linked polythiophene nanowires. As the aptamer functionalized poly (3-methylthiophene) nanowire is treated by the specific protein, resonance Raman and photoluminescence signals are simultaneously enhanced. Statistical analyses deliver the capability of a single conjugated polymer nanowire with phase-transition characteristics in response to selectivity and concentration.

Enhanced intrapulmonary delivery of anticancer siRNA for lung cancer therapy using cationic ethylphosphocholine-based nanolipoplexes.

Here, we report a cationic nanolipoplex as a pulmonary cellular delivery system for small-interfering RNA (siRNA). Six nanoliposomes differing in cationic lipids were formulated and screened in vitro and in vivo for cellular delivery functions in lung cells/tissues. Although the six nanoliposomes showed similar siRNA delivery efficiency in vitro, they exhibited significant differences in pulmonary cellular delivery functions in vivo. Among the various nanoliposomes, cationic dioleoyl-sn-glycero-3-ethylphosphocholine and cholesterol (ECL)-based nanoliposomes showed the highest pulmonary cellular delivery in vivo and the lowest cytotoxicity in vitro. The delivery efficiency of fluorescent siRNA in ECL nanoliposomes was 26.2-fold higher than that of naked siRNA in vivo. Treatment with Mcl1 (myeloid cell leukemia sequence 1)-specific siRNA (siMcl1) using ECL nanolipoplexes reduced target expression in B16F10 cell lines, whereas control, luciferase-specific siGL2 in ECL nanolipoplexes did not. In metastatic lung cancer mouse models induced by B16F10 or Lewis lung carcinoma (LLC) cells, intratracheal administration of siMcl1 in ECL nanolipoplexes significantly silenced Mcl1 mRNA and protein levels in lung tissue. Reduced formation of melanoma tumor nodules was observed in the lung. These results demonstrate the utility of ECL nanoliposomes for pulmonary delivery of therapeutic siRNA for the treatment of lung cancers and potentially for other respiratory diseases.

Preparation of electrospun polyurethane filter media and their collection mechanisms for ultrafine particles.

UNLABELLED: Electrospinning is a simple and versatile process to produce polymer nanofibers, which are useful for ultrafine particle filtration. In this study, a polyurethane filter with an average fiber diameter of 150-250 nm was prepared through the electrospinning process and its filtration characteristics were investigated. We found that the electrospun fiber diameter was highly dependent on the polyurethane concentration, electric field, and tip-to-collector distance. As the polyurethane concentration, electric field, and tip-to-collector distance under the same electric field increased, the fiber diameter increased. We also found that the produced filter media had a minimum collection efficiency at particles sizes from 80 to 100 nm, which implies an electrostatic attraction between the filter and the test particles. Furthermore, we observed that interception was a predominant collection mechanism at Peclet numbers higher than 10 in nanofiber filtration for ultrafine particles. IMPLICATIONS: A polyurethane nanofiber filter with excellent mechanical properties was prepared, and the effect of operating conditions on fiber morphology was examined. The filter fabricated by an electrospinning process is charged and has high filtration efficiency due to electrostatic force. Therefore, it can be a good alternative to control hazardous ultrafine particles.

Morphometric analysis of the upper lip in Koreans.

The aims of this study were to provide the various dimensions of the philtrum and upper red lip in Korean young adults and to identify morphological characteristics of these structures in Koreans. A total of 10 dimensions of the philtrum and upper red lip were measured in 251 healthy young adults. Various indices were calculated among the measured features. The philtrum could be classified into three types according to its shape and index data. The mean height of the philtrum was 15.6 mm and the mean width of the mouth was 45.5 mm. The width of the superior and inferior philtrum, the height of philtrum, the width of the mouth, and the height of the upper red lip were significantly larger in males than in females (p < 0.05). A subtle morphological difference in Cupid bow was observed between the genders. There was a negative correlation between the length of the philtral column and the height of the upper red lip (p < 0.05). Furthermore, differences were identified in the dimensions of the philtrum and the upper red lip between Koreans and Caucasians. The results of this study could be a useful morphological basis for correction and reconstruction of the upper lip.

Pyogenic granuloma of the hard palate leading to alveolar cleft: a case report.

This case report describes a rare occurrence of pyogenic granuloma (PG) in the hard palate deviating from its typical gingival location that led to the formation of an alveolar cleft. The aggressive growth pattern of the lesion, with atypical progression from a pedunculated nodule to an alveolar cleft, raised concern. The diagnosis was based on magnetic resonance imaging and computed tomography findings, which revealed a tadpole-shaped lesion originating from the midline hard palate. The differential diagnosis included a minor salivary gland tumor. Surgical excision was performed under general anesthesia and resulted in a mucosal defect without nasolabial fistula formation or bone exposure. The palatal defect was packed with oxidized regenerated cellulose and closed with Vicryl Rapide sutures, both of which contributed to the patient's successful outcomes. Our comprehensive approach, extending across the stages of surgical planning, execution, and postoperative care, demonstrated the advantages of a multidisciplinary strategy for the accurate diagnosis and effective treatment of palatal PGs. This report makes a meaningful contribution to the existing literature on common oral lesions by emphasizing the importance of a broad differential diagnosis and a systematic approach to oral pathologies. It also raises clinical awareness of PGs with atypical presentations and the diagnostic challenge that they pose.

Self-controllable proteinic antibacterial coating with bacteria-triggered antibiotic release for prevention of periprosthetic infection.

Periprosthetic infection is a devastating postimplantation complication in which a biofilm layer harboring invasive microorganisms forms around orthopedic implants, leading to severe implant failure and patient morbidity. Despite the development of several infection-triggered antibiotic release approaches, most current antibacterial coatings are susceptible to undesired antibiotic leakage or mechanical disintegration during prosthesis installation. Herein, we propose a self-controllable proteinic antibacterial coating capable of both long-lasting adherence onto titanium implant substrates over the implant fixation period and instantaneous bacterial eradication. Importantly, the pH-dependent reversible metal coordination of mussel adhesive protein (MAP) enabled bacterial concentration-dependent antibiotic delivery in response to infection-induced acidification. In addition, the MAP coating exhibited superior self-healable adhesive properties and scratch resistance, which enabled to avert issues associated with mechanical damages, including peeling and cracking, often occurring in conventional implant coating systems. The gentamicin-loaded MAP coating exhibited complete inhibition of bacterial growth in vivo against Staphylococcus aureus penetrations during implantation surgery (immediate infection) and even 4 weeks after implantation (delayed infection). Thus, our antibiotic-loaded MAP hydrogel coating can open new avenues for self-defensive antibiotic prophylaxis to achieve instant and sustainable bacteriocidal activity in orthopedic prostheses. © 2017 Elsevier Inc. All rights reserved.

Prevalence and factors associated with neck and jaw muscle modulation of tinnitus.

Forceful contractions of neck and jaw muscles have consistently been shown to modulate tinnitus and can be used to screen patients who are responsive to somatic stimulation and, therefore, optimal candidates for somatosensory-based treatment. To identify the factors associated with somatic modulation of tinnitus, 163 patients underwent 19 neck and jaw maneuvers after an extensive physiological and audiological profile was compiled. Overall, tinnitus was modulated in 57.1% of ears tested. Unilateral tinnitus showed greater prevalence of modulation. Neck maneuvers generally decreased tinnitus loudness, whereas jaw maneuvers increased loudness. Female gender and buzzing tinnitus were associated with a high prevalence of modulation and a decrease in tinnitus loudness. Loud tinnitus and low-pitched tonal tinnitus were associated with exacerbation of the condition as a result of somatic testing. Use of these characteristics to select optimal candidates for somatosensory-based tinnitus therapies may be essential for the development of an effective approach for tinnitus treatment.

Technical feasibility and revision efficacy of the sequential deployment of endoscopic bilateral side-by-side metal stents for malignant hilar biliary strictures: a multicenter prospective study.

BACKGROUND: Theoretically, the side-by-side bilateral placement of metal stents may be technically easier than stent-in-stent bilateral placement in stent revision. However, side-by-side placement can be technically challenging, as the deployment of the first stent can preclude the passage of the second stent. AIM: We explored the technical feasibility and revision efficacy of endoscopic bilateral side-by-side stent placement for malignant hilar biliary strictures. METHODS: Forty-four patients with Bismuth type II or higher malignant hilar biliary strictures were enrolled in seven academic tertiary referral centers. Endoscopic placement of side-by-side bilateral metal stents with 7F thin delivery shaft was performed. The outcome measurements were the technical and functional success, adverse events, endoscopic revision success rate, and stent patency. RESULTS: Overall, the technical and functional success rates were 91 % (40/44), and 98 % (39/40), respectively. Two of the failed patients were converted successfully with subsequent contralateral stent-in-stent placement, and the other patients underwent percutaneous intervention. Early stent-related adverse events occurred in 10 %. The endoscopic revision rate due to stent malfunction during follow-up (median: 180 days) was 45 % (18/40; tumor ingrowth in 4 and in-stent sludge impaction/stone formation in 14 patients). The endoscopic revision success rate was 92 % (12/13). Five patients with comorbidity underwent initial percutaneous intervention. The median survival and stent patency periods were 180 and 157 days, respectively. CONCLUSIONS: The sequential placement of a metal stent with a 7F thin delivery shaft in bilateral side-by-side procedures may be feasible and effective for malignant hilar biliary strictures and for endoscopic stent revision.

Centralization or decentralization of facial structures in Korean young adults.

It is well known that facial beauty is dictated by facial type, and harmony between the eyes, nose, and mouth. Furthermore, facial impression is judged according to the overall facial contour and the relationship between the facial structures. The aims of the present study were to determine the optimal criteria for the assessment of gathering or separation of the facial structures and to define standardized ratios for centralization or decentralization of the facial structures.Four different lengths were measured, and 2 indexes were calculated from standardized photographs of 551 volunteers. Centralization and decentralization were assessed using the width index (interpupillary distance / facial width) and height index (eyes-mouth distance / facial height). The mean ranges of the width index and height index were 42.0 to 45.0 and 36.0 to 39.0, respectively. The width index did not differ with sex, but males had more decentralized faces, and females had more centralized faces, vertically. The incidence rate of decentralized faces among the men was 30.3%, and that of centralized faces among the women was 25.2%.The mean ranges in width and height indexes have been determined in a Korean population. Faces with width and height index scores under and over the median ranges are determined to be "centralized" and "decentralized," respectively.

Efficacy of closed cell self expandable metallic stent for peripheral arterial disease in the porcine iliac artery.

This study aimed to investigate the efficacy of a closed-cell self-expandable metallic stent (SEMS) with or without expanded-polytetrafluoroethylene (e-PTFE)-covering membrane in a porcine iliac artery model. Twelve Yorkshire domestic pigs were divided into a bare closed-cell SEMS (B-SEMS) group (n = 6) and covered closed-cell SEMS (C-SEMS) group (n = 6). Both closed-cell SEMSs were placed in the right or left iliac artery. Thrombogenicity score in the C-SEMS group was significantly higher than that in the B-SEMS group (p = 0.004) after 4 weeks. Angiographic findings of mean luminal diameters at 4 weeks follow-up did not differ significantly between B-SEMS and C-SEMS groups. Neointimal hyperplasia thickness as well as degree of inflammatory cell infiltration and collagen deposition in the C-SEMS group was significantly greater than that in the B-SEMS group (p < 0.001). Closed-cell SEMSs successfully maintained patency for 4 weeks without stent-related complications in the porcine iliac artery. Although mild thrombus with neointimal hyperplasia was observed in the C-SEMS group, subsequent occlusion, and in-stent stenosis did not occur in any of the pigs until the end of the study. Closed-cell SEMS with or without the e-PTFE covering membrane is effective and safe for the porcine iliac artery.

Feasibility of placing a modified fully covered self-expandable metal stent above the papilla to minimize stent-induced bile duct injury in patients with refractory benign biliary strictures (with videos).

BACKGROUND: Endoscopic placement of fully covered self-expandable metal stents (FCSEMS) has been attempted to manage benign biliary strictures, but currently available FCSEMSs may be associated with unintended complications, including de novo strictures, in patients with normal life expectancy. OBJECTIVE: To evaluate the feasibility of an intraductally placed modified FCSEMS to minimize stent-induced bile duct injury in patients with benign biliary strictures. DESIGN: Prospective observational clinical feasibility study. SETTING: Tertiary-care academic center. PATIENTS: This study involved 21 patients with symptomatic benign biliary strictures in whom conventional endoscopic management failed. INTERVENTION: Strictured segments were 15 mm above the ampulla of Vater. The modified FCSEMS has convex margins, a lasso, and an anti-migrating waist on the central portion. Stents were placed entirely above the papilla and removed after 3 to 5 months. MAIN OUTCOME MEASUREMENTS: Success, complications, removability, midterm outcome. RESULTS: FCSEMSs were successfully placed inside the bile duct in all patients. No episodes of pancreatitis, cholangitis, or sepsis were noted during the stenting period. Stent migration occurred in 4 patients (19.0%), but 3 were asymptomatic during follow-up. All stents were removed successfully with rat-tooth forceps without complications. Post-stenting cholangiograms showed improvement of strictures in 20 of 21 patients, without de novo focal stricture. The clinical success rate was 95.2%, with one recurrent stricture. LIMITATIONS: The small number and lack of comparison with other types of FCSEMSs. CONCLUSION: Temporary intraductal placement of a newly modified FCSEMS effectively improved strictures and prevented potential stent-induced complications in patients with benign biliary strictures. Controlled large-scale trials are needed to confirm the long-term efficacy.

Adjacent segment degeneration after lumbar dynamic stabilization using pedicle screws and a nitinol spring rod system with 2-year minimum follow-up.

STUDY DESIGN: Prospective study evaluating the adjacent segment degeneration after lumbar dynamic stabilization using pedicle screws and a Nitinol spring rod system. OBJECTIVE: To assess the changes of the adjacent and implantation segments after lumbar dynamic stabilization surgery using magnetic resonance imaging (MRI). SUMMARY OF BACKGROUND DATA: Lumbar fusion operations can accelerate the degeneration of adjacent levels. Recently, motion preservation surgery has been attempted for the treatment of lumbar degenerative diseases to prevent degeneration of adjacent levels. However, there is a controversy over whether lumbar dynamic stabilization accelerates degeneration of adjacent levels. METHODS: We performed the dynamic stabilization procedure in patients with grade 1 degenerative lumbar spondylolisthesis, lumbar spondylotic stenosis with segmental instability, or a herniated lumbar disc with segmental instability. Postoperative MRI scans were taken for >2 years in all enrolled 25 patients. We compared the findings regarding disc degeneration in the cranial, implantation, and caudal segments between the preoperative period and 2-year-plus postoperative period using T2-weighted sagittal MR images. In addition, we investigated the progression of the central and foraminal stenosis of the adjacent cranial and caudal levels. RESULTS: Three of the 25 cranial adjacent discs (12.0%) and 4 of the 25 (16%) caudal adjacent discs demonstrated progression of degeneration after dynamic stabilization. One of the 13 discs in the implantation segment demonstrated progression of degeneration, and 2 of the 13 discs in the implantation segment showed improvement of their disc degeneration (disc rehydration). A total of 5 (10.0%) of the 50 segments (3 cranial and 2 caudal adjacent) showed increased spinal stenosis postoperatively. Among the 5 cases, 3 patients had symptomatic adjacent stenosis. CONCLUSION: According to our results, lumbar dynamic stabilization using pedicle screws and a Nitinol spring rod system may not prevent adjacent level degeneration completely.

Anatomical verification and designation of the superficial layer of the temporalis muscle.

The temporalis muscle, which is one of the masticatory muscles, enables elevation and retraction of the mandible. Direct injury to the temporalis muscle, facial nerve, or temporal fat pad during cranial-base surgery can cause temporal hollowing. The temporalis muscle is currently described in almost all atlases and textbooks as comprising a single layer. In this study, a superficial layer of the temporalis muscle is described, clarifying the anatomy of this muscle. Twenty heads of adult cadavers were dissected. The gross anatomy of the temporalis muscle was examined after removing the skin, subcutaneous tissue, superficial temporal fascia, and deep temporal fascia. The superficial layer of the temporalis muscle was clearly distinguishable from the deep layer. The superficial layer originated from the same region as the deep layer, and the muscle fibers of the two layers were intermingled in the superior part of the muscle. The deep layer of the temporalis muscle, which is referred to in textbooks and atlases simply as the temporalis muscle, was exposed after removing the superficial layer. The existence of this superficial layer was confirmed herein both histologically and by magnetic resonance imaging. Henceforth, the superficial layer of the temporalis muscle must be included in descriptions of the temporalis muscle in anatomy textbooks and atlases. The findings of this study are important not only from the perspective of simply acquiring correct anatomical knowledge, but also from the surgical perspective in preventing temporal hollowing during related surgical procedures.

Efficacy of thermoplastic polyurethane and gelatin blended nanofibers covered stent graft in the porcine iliac artery.

Stent-grafts composed of expanded polytetrafluoroethylene (e-PTFE), polyethylene terephthalate (PET) and polyurethane (PU) are characterized by poor endothelialization, high modulus, and low compliance, leading to thrombosis and intimal hyperplasia. A composite synthetic/natural matrix is considered a promising alternative to conventional synthetic stent-grafts. This study aimed to investigate the efficacy of thermoplastic polyurethane (TPU) and gelatin (GL) blended nanofibers (NFs) covered stent-graft in the porcine iliac artery. Twelve pigs were randomly sacrificed 7 days (n = 6) and 28 days (n = 6) after stent-graft placement. The thrombogenicity score at 28 days was significantly increased compared at 7 days (p < 0.001). The thickness of neointimal hyperplasia, degree of inflammatory cell infiltration, and degree of collagen deposition were significantly higher at 28 days than at 7 days (all p < 0.001). The TPU and GL blended NFs-covered stent-grafts successfully maintained the patency for 28 days in the porcine iliac artery. Although thrombosis with neointimal tissue were observed, no subsequent occlusion of the stent-graft was noted until the end of the study. Composite synthetic/natural matrix-covered stent-grafts may be promising for prolonging stent-graft patency.

Anchoring of a fully covered self-expandable metal stent with a 5F double-pigtail plastic stent to prevent migration in the management of benign biliary strictures.

OBJECTIVES: Fully covered self-expandable metal stents (FCSEMSs) can be effectively placed in patients with benign biliary stricture (BBS). However, stent migration is an inherent problem of FCSEMSs. We evaluated the efficacy of anchoring with a 5F double-pigtail plastic stent (anchoring stent) to prevent migration of an FCSEMS in patients with BBS. METHODS: Between January 2007 and December 2009, 33 of 37 consecutive patients with BBS who had experienced treatment failure of at least one plastic stent placement were prospectively enrolled in this study. The patients with BBS were randomly assigned to undergo FCSEMS placement with or without an anchoring stent (anchoring group: 16 patients; non-anchoring group: 17 patients). The main outcome measures were the stent migration rate and success rates. RESULTS: The technical success rate was 100% in both groups. Significantly less stent migration occurred in the anchoring group (6.3%, 1/16) than in the non-anchoring group (41.2%, 7/17; P=0.024). The median indwelling time was significantly longer in the anchoring group (154 days; range, 86-176 days) than in the non-anchoring group (114 days; range, 19-162 days; P=0.010). Improvement or resolution of the BBS was confirmed in 15 of 16 patients (93.8%) in the anchoring group, and in 12 of 17 patients (70.6%) in the non-anchoring group (P=0.101). CONCLUSIONS: The placement of an anchoring stent appears to be a simple and effective method of preventing premature migration of FCSEMSs in patients with BBS. Appropriately powered studies are needed to confirm this finding.

Single pixel transmissive and reflective liquid crystal display using broadband cholesteric liquid crystal film.

We propose a single mode transflective liquid crystal display (LCD) which is operated as the transmissive and reflective modes in a single pixel without dividing into sub-pixels. The single pixel transflective LCD was composed of the cross-polarized nematic LCD as a light modulator and the broadband cholesteric liquid crystal film (BCLCF) as a half mirror. The BCLCF, simply prepared by the exposure of ultraviolet light to the mixture of the nematic LC and the reactive mesogen with chirality, selectively reflects a certain circular polarization but transmits the orthogonal circular polarization in entire visible light. The electro-optical properties in both transmissive and reflective modes coincide with each other.

Outcome of palliative self-expanding metal stent placement in malignant colorectal obstruction according to stent type and manufacturer.

BACKGROUND: Self-expandable metallic stents (SEMS) of varying designs and materials have been developed to reduce complications, but few comparative data are available with regard to the type of stent and the stent manufacturer. We analyzed the success rates and complication rates, according to stent type (uncovered vs. covered stent) and individual stent manufacturer, in malignant colorectal obstruction. METHODS: From November 2001 to August 2008, 103 patients were retrospectively included in this study: four types of uncovered stents in 73 patients and two types of covered stents in 30 patients. The SEMS was inserted into the obstructive site by using the through-the-scope method. RESULTS: Technical and clinical success rates were not different between stent type or among stent manufacturers: 100 and 100% (p = ns) and 100 and 96.6% (p > 0.05), respectively, in uncovered and covered stents. Stent occlusion and migration rates were 12.3 and 3.3% (p = 0.274) and 13.7 and 16.7% (p = 0.761), respectively, in uncovered and covered stents, and 11.1, 5, and 9% (p = 0.761) and 25.9, 15, and 0% (p = 0.037) in Wallstent, Niti-S, and Bonastent uncovered stents, respectively. CONCLUSIONS: The placement of SEMS is an effective and safe treatment for patients with malignant colorectal obstruction. Although minor differences in outcome were detected according to the type and the manufacturer of the stents, no statistically significant difference was observed, except in stent migration among the stent manufacturer.