Biodegradable polymer membrane used as septal splint

Use of alloplastic implants for correction of deviated nasal septum: Systematic review and meta-analysis

PURPOSE

To systematically reviews the safety and effectiveness of alloplastic implants (AI) in septoplasty.

METHODS

We conducted a comprehensive search in Medline, EMBASE, SCOPUS, CINAHL, and Cochrane Library databases to identify articles on septoplasty using AI. We also manually searched reference lists of included articles. Inclusion criteria involved prospective or retrospective case-series studies of adults with deviated nasal septum (DNS) who underwent septoplasty with AI, with sufficient follow-up data. Two authors independently screened articles, reviewed full manuscripts, and extracted data.

RESULTS

Out of 5370 articles, 16 met inclusion criteria, encompassing 884 patients from 14 eligible studies. Most studies had fair quality. AI materials included Polydioxanone (PDS), Polycaprolactone (PCL), Titanium, Macropore, and PolyMax. AI usage improved nasal obstruction in most patients, with 95.6 % (84.8 %-100 %) based on physical examination and 96.9 % (89.6 %-100 %) based on symptoms. AI-related complications occurred in 4.3 % (0 %-12.8 %) of cases, mostly non-serious.

CONCLUSIONS

AI use can be considered as a useful adjunct in septoplasty, with uncommon complications similar to standard procedures. However, due to limited-quality evidence, further prospective controlled studies are needed.

Partial nasal bone reconstruction with acrylic bone cement: experimental study

Background

The aim of this study was to evaluate the effectiveness of acrylic bone cement in partial nasal bone reconstruction.

Methods

This study was conducted using nine New Zealand rabbits. The left nasal bones of the rabbits were included in the experimental group, and the right nasal bones were evaluated as the control group. The partial bone segments on the bilateral nasal bones were marked and removed symmetrically. A synthetic graft material made of acrylic bone cement was placed in experimental group, and the partial bone segment removed from the right side was placed in control group as an autograft. All rabbits were sacrificed at the end of the 28th day. Samples were taken from the grafts and from the surrounding soft tissues for histopathological examination. Acute inflammation, chronic inflammation, vascularization, fibrosis, foreign body reaction, bone proliferation, and the presence of empty lacunae were evaluated under a light microscope for both groups.

Results

Surrounding soft tissue on synthetic and autograft were the same in terms of chronic inflammation. There was no statistically significant difference for vascularization, fibrosis, and foreign body reaction. Synthetic graft and autograft were the same in terms of chronic inflammation, fibrosis, and bone proliferation. There was no statistically significant difference for vascularization, foreign body reaction, and presence of empty lacunae (p > 0.05).

Conclusion

This study showed no significant differences between the use of acrylic bone and the use of an autograft for partial nasal bone reconstruction in terms of graft or tissue healing. Acrylic bone cement may therefore serve as a good alternative for nasal bone reconstruction.

Absorbable plate as a perpendicular strut for acute saddle nose deformities

BACKGROUND

Nasal pyramid fractures accompanied by saddle nose deformities are not easily corrected by closed reduction. We used an absorbable plate as a perpendicular strut to support the collapsed "keystone area" and obtained good results.

METHODS

Between September 2008 and June 2011, 18 patients who had nasal pyramid fractures with saddle nose deformities underwent surgery. Pre- and postoperative facial computed tomographic images and photographs were taken to estimate outcomes. The operative technique included the mucoperichondrial dissection of the nasal septum, insertion of an absorbable plate prepared to an appropriate length to support the "keystone area", and fixation of the absorbable plate strut to the cartilaginous septum.

RESULTS

Functional and esthetic outcomes were satisfactory in all patients. Eleven patients assessed the postoperative appearance of the external nose as 'markedly improved' and 7 patients as 'improved'. The 5 surgeons scored the results as a mean of 4.5 on a 5-point scale.

CONCLUSIONS

The use of an absorbable plate as a perpendicular strut requires no additional procedures because the plate is gradually absorbed. The mechanical strength provided by a buttress between the "keystone area" and the maxillary crest lasts for a long time before the strut is absorbed.

Assessment of biphasic calcium phosphate to repair nasal septum defects in sheep

BACKGROUND

Saddle nose and septal perforations are among the most surgically challenging situations in nasal reconstruction. They require a significant volume of autologous graft and a complex surgical procedure. The aim of this study was to evaluate the biocompatibility of the biphasic calcium phosphate implant in the nasal septum and its ability to replace septal skeleton with unilateral or bilateral exposure.

METHODS

Thirty sheep underwent anterior nasal septum perforation. Only 20 septa were repaired with the implant exposed to nasal content on bilateral (group 2) and unilateral (group 3) sides. After 45 days of spontaneous cicatrization, the surface of new airway mucosa covering implants and the amount of closure were evaluated macroscopically. Light microscopy, histomorphometry, immunohistochemistry, and transmission electron microscopy were performed to assess soft-tissue growth and differentiation. Statistical analysis was performed by means of the Mann-Whitney test.

RESULTS

The mean rate of mucoperichondrial flap recovery of the implant was 66 percent in group 2 and 82 percent in group 3, and was significantly different from that of the control group (p < 10(-4)). The mean amount of closure was 32 and 64 percent, respectively (p < 10(-3)). The thickness of the perichondrium was greater than the control on both sides (p < 10(-4)). Vascularized soft tissues and bone formation invaded pores of implants. No pathologic inflammation was observed in submucosa. Moderately differentiated and well differentiated newly formed epithelium were the most frequent types observed, with good correlation between immunostaining and morphologic features.

CONCLUSION

These data suggest a good biocompatibility of biphasic calcium phosphate and its ability to repair the nasal septum in sheep.

Porous hollow membrane sheet for tissue engineering applications

In spite of the present advances in the scaffolds fabrication and bioreactor systems, the ability to create functional thick tissue masses in vitro is still a great tissue engineering challenge. To overcome this problem, the fabrication of a capillary bed, for nutrient supply to and waste product removal from the tissue engineering construct as it grows, is essential. However, the technical construction of a capillary-like architecture is complex and challenging. This study reports, for the very first time, a simple method to design and fabricate a porous hollow membrane sheet (PHMsh) to provide both a capillary bed and a scaffold to support tissue growth. The PHMsh composed of a flexible porous sheet involving parallel porous channels and can be used as flat-, rolled-, or sandwiched-shape scaffold. The PHMsh was fabricated from poly(epsilon-caprolactone) polymer solution using solvent casting methods (i.e., immersion precipitation and air casting). Optical microscopy and scanning electron microscopy were used for the morphological analyses. The PHMsh was surface treated using n-hepthylamine plasma polymer (HApp) and X-ray photoelectron spectroscopy confirmed successful surface coating. Human umbilical vein endothelial cells (HUVECs) and fibroblast cells were used to evaluate the capability of PHMsh toward cell adhesion. The HApp coating enhanced both HUVEC and fibroblast cells adhesion. The obtained preliminary results demonstrated the successful fabrication of the PHMsh, with potential application for tissue engineering scaffolds, particularly in large tissue mass generation under perfusion systems in vitro, which is our future research direction.

Biphasic calcium phosphate to repair nasal septum: the first in vitro and in vivo study

Our objective was to evaluate the cytocompatibility and biocompatibility of biphasic calcium phosphate (BCP) in the nasal respiratory airway. In vitro, the attachment rate was quantified on BCP disks with normal human epithelial cells at 1, 3 and 24 h by determining N-acetyl beta-D-hexosaminidase activity. Proliferative activity of cells was indirectly assessed by MTT assay at 3, 9, 15 and 21 days. Plastic surfaces were used as positive control. In vivo, 15 rabbits underwent anterior nasal septum perforation and 10 septa were repaired with BCP disks. Five non-implanted animals were sacrificed at 3 months. Two groups of five implanted animals were sacrificed at 1 and 2 months. The surface of new airway mucosa covering BCP disks was evaluated macroscopically. During both steps, light microscopy, immunohistochemistry and scanning electron microscopy were performed. Statistical analysis was performed with the Mann-Whitney U-test. In vitro, at 1 and 3 h, the attachment rates were significantly better than on the plastic surface (p < 10(-2)). Mitochondrial activity increased on both surfaces but began 6 days later than on plastic. After 21 days of culture, cells were confluent and formed a monolayer covering the implant even in the bottom of the pores. In vivo, no perforations in the control group closed spontaneously. The mean rate of closure was 63% in the 1 month group and 64% in the 2 month group (p > 0.05). Implants were invaded by inflammatory reaction covered by incomplete differentiated respiratory epithelium. Throughout the study, all immunohistochemical findings remained positive. These data suggest a good affinity between BCP and nasal epithelial cells. BCP could be used to rebuild nasal septa.