Evaluation of a new skin closure device in surgical incisions associated with breast procedures

Comparison of 2-octyl cyanoacrylate with polyester mesh with standard suture and staples in total knee and hip arthroplasty

OBJECTIVE

The use of 2-octyl cyanoacrylate with polyester mesh (OCA-M) has become common in total hip and knee arthroplasty (THA, TKA). We aimed to compare the safety and cosmetic outcomes between OCA-M and standard suture techniques and staples, and determine whether OCA-M can safely be used for TKA.

METHOD

Inclusion criteria were patients who underwent THA or TKA from January 2010 to October 2011 (Suture group), November 2011 to August 2013 (Staple group), March 2017 to September 2018 (OCA-M group). Exclusion criteria was loss of imaging data. Complications during hospitalisation (early complication) and after discharge (late complication) were compared in groups. Plastic and orthopaedic surgeons performed cosmetic evaluations with the modified Vancouver Scar Scale (VSS) and Likert scale at three and six months postoperatively and compared in groups.

RESULTS

A total of 249 arthroplasties (suture group=88 patients; staple group=94 patients; OCA-M group=67 patients) were included in the study. The OCA-M group had a significantly lower early complication rate than the suture group (p=0.015). For THA, the OCA-M group had a significantly lower total complication rate than the suture group (p=0.048). For TKA, there was no significant difference among the three groups. The complication rate in the OCA-M group showed no significant difference between THA/TKA. With regards to the VSS, the OCA-M group was significantly better for cosmetic qualities than the suture group (p=<0.001, p=0.021 at three and six months, respectively). For the Likert scale, the OCA-M group was also significantly better for cosmetic qualities than the suture group and staple group (suture-OCA-M, p=0.003 (three months), p=<0.001 (six months); staple-OCA-M, p=0.027 (three months)).

CONCLUSION

In this study, the OCA-M complication rate was low compared to suturing and similar to stapling. Moreover, better cosmetic outcomes were achieved compared to suturing and stapling.

Topical skin adhesive PRINEO as the ideal wound closure system in cardiac surgery to limit surgical site infection

OBJECTIVE

Surgical site infections (SSIs) are a major source of morbidity after cardiac surgery, involving prolonged hospitalisation. Among the numerous techniques of skin closure and dressings available, the optimal method remains undetermined. The DERMABOND-PRINEO (PRINEO) (PRINEO, Ethicon, J&J) is the only skin closure system which combines a topical skin adhesive with a mesh. Other surgical disciplines have highlighted remarkable results with PRINEO. The aim of this study was to evaluate the effects of PRINEO, used as the final layer in sternotomy closure, in the incidence of postoperative SSIs.

METHOD

This was a retrospective single-centre cohort study including adult patients who underwent cardiac surgery between January 2015 and December 2018. Patients who had undergone heart transplantation or ventricular assist surgery were excluded. Included patients were divided into two groups depending on the type of post-operative wound care technique used. Group 1 consisted of patients who had their sternotomy closed with a standard dressing and group 2 consisted of patients who were treated with PRINEO. The primary endpoint of our study was the occurrence of SSIs and secondary outcomes were the length of hospitalisation and mortality.

RESULTS

A total of 1603 patients were reviewed with the occurrence of 44 SSIs. Both groups were homogeneous in terms of risk factors. The incidence of SSIs was significantly lower in group 2 (PRINEO) than in group 1 (standard dressing) (n=29, 3.8% vs n=15, 1.8%, respectively; p=0.042). However, there was no significant difference in the duration of hospitalisation and mortality.

CONCLUSION

In our practice, PRINEO has proven to be a safe wound closure system after sternotomy, with a reduced SSI rate compared to conventional wound care techniques.

Comparing Dermabond PRINEO versus Dermabond or staples for wound closure: a randomized control trial following total shoulder arthroplasty

BACKGROUND

The method of surgical incision closure after total shoulder arthroplasty is an important factor to consider, as it affects operating room time, procedure cost, cosmetic outcomes, and patient satisfaction. The optimal method of wound management is unknown, but should be cost-effective, reproducible, and provide a reliable clinical result. This study aimed to compare the following wound closure methods after total shoulder arthroplasty: staples, Dermabond, and Dermabond PRINEO. We hypothesized that wound closure time for Dermabond PRINEO would be faster than Dermabond and comparable to that of staples, and Dermabond PRINEO would be more cost-effective than Dermabond and staples, and provide equal or superior closure outcomes to Dermabond and staples.

METHODS

A randomized, prospective clinical trial comparing wound closure time and cost for 2 surgeons' traditional technique with that of Dermabond PRINEO was conducted. This study included at least 18 subjects in each group. Surgeon 1's patients were randomized to traditional Dermabond or Dermabond PRINEO, whereas surgeon 2's patients were randomized to staples or Dermabond PRINEO. Cosmetic outcomes and satisfaction scores were collected at 6 weeks and 3 months, postoperatively. Incisions were photographed, at both the 6-week and 3-month visits, and subsequently evaluated by a plastic surgeon blinded to the treatment method.

RESULTS

The wound closure time for surgeon 1 was significantly faster for Dermabond PRINEO vs. Dermabond, and surgeon 2 closed significantly faster with staples vs. Dermabond PRINEO. The mean cost of closure was significantly less with Dermabond PRINEO compared with Dermabond, whereas the mean cost of staples was significantly less than Dermabond PRINEO. For both surgeons 1 and 2, there were no significant differences in patient satisfaction at 6 weeks or 3 months. In addition, the wound closure methods did not produce differing cosmetic outcomes.

CONCLUSIONS

Although significant, the closing time for each method did not differ by a clinically relevant amount. Staples were the most cost-effective closing method, followed by Dermabond PRINEO. As neither method was superior over the other in terms of patient satisfaction, adverse events, and cosmetic outcomes, cost-effectiveness may be the greatest differentiator between the 3 methods.

Allergic dermatitis after knee arthroscopy with repeated exposure to Dermabond Prineo™ in pediatric patients: Two case reports

BACKGROUND

Allergic contact dermatitis (ACD) secondary to Dermabond Prineo™ is rare, but documented. To our knowledge, there are no described reports of this ACD reaction within the pediatric population following arthroscopic surgery.

CASE SUMMARY

We report two cases of pediatric ACD upon second exposure to Dermabond Prineo™ after knee arthroscopy. Both cases presented within two weeks of the inciting second exposure. The cases resolved with differing described combinations of sterile cleaning, diphenhydramine, and antibiotic administration. No long-term sequelae were found.

CONCLUSION

This case report elucidates the rare complication of allergic dermatitis secondary to Dermabond Prineo™ repeat exposure use in pediatric arthroscopy.

Polyester mesh dressings reduce delayed wound healing rates after total hip arthroplasty compared with silver-impregnated occlusive dressings

Background

New dressings purport to reduce surgical wound complications after total hip arthroplasty (THA). This study compared delayed wound healing rates and reoperations between 2 increasingly popular dressings: a silver-impregnated occlusive (standard) dressing and a 2-octyl cyanoacrylate adhesive with polyester mesh.

Methods

This retrospective cohort study reviewed 431 consecutive THAs performed by 2 surgeons between January 2017 and May 2019. One hundred and eight were excluded for not using standard or mesh dressings. A final 323 cases were separated into 2 cohorts: mesh (n = 186) and standard dressings (n = 137). Standard dressings were removed at 1 week. Mesh persisted until nonadherent, approximately 3-4 weeks. The surgeon assessed delayed wound healing at the 2-week postoperative visit. Secondary outcomes include deep infection and return to the operating room for a wound-related diagnosis. Differences were determined using the chi-square test.

Results

There were no demographic, comorbidity, or surgical differences between groups. There were 22 total cases of delayed wound healing with 7 (3.8%) in the mesh group and 15 (10.9%) in the standard dressing group (P = .01). There were no significant differences in reoperations (2 [1.1%] vs 2 [1.5%], P = .76) or deep infections (2 [1.1%] vs 1 [0.7%], P = .75).

Conclusions

Mesh dressings are a safe and reliable dressing type for THA and were associated with a decrease in early wound healing complications when compared with standard, silver-impregnated occlusive dressings in this retrospective series. The mesh tension sharing properties and longer duration of occlusive protection may explain this difference.

Level of Evidence

Level III.

Subcuticular sutures for skin closure in non-obstetric surgery

BACKGROUND

Following surgery, surgical wounds can be closed using a variety of devices including sutures (subcuticular or transdermal), staples and tissue adhesives. Subcuticular sutures are intradermal stitches (placed immediately below the epidermal layer). The increased availability of synthetic absorbable filaments (stitches which are absorbed by the body and do not have to be removed) has led to an increased use of subcuticular sutures. However, in non-obstetric surgery, there is still controversy about whether subcuticular sutures increase the incidence of wound complications.

OBJECTIVES

To examine the efficacy and acceptability of subcuticular sutures for skin closure in non-obstetric surgery.

SEARCH METHODS

In March 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

All randomised controlled trials which compared subcuticular sutures with any other methods for skin closure in non-obstetric surgery were included in the review.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified the trials, extracted data and carried out risk of bias and GRADE assessment of the certainty of the evidence.

MAIN RESULTS

We included 66 studies (7487 participants); 11 included trials had more than two arms. Most trials had poorly-reported methodology, meaning that it is unclear whether they were at high risk of bias. Most trials compared subcuticular sutures with transdermal sutures, skin staples or tissue adhesives. Most outcomes prespecified in the review protocol were reported. The certainty of evidence varied from high to very low in the comparisons of subcuticular sutures with transdermal sutures or staples and tissue adhesives; the certainty of the evidence for the comparison with surgical tapes and zippers was low to very low. Most evidence was downgraded for imprecision or risk of bias. Although the majority of studies enrolled people who underwent CDC class 1 (clean) surgeries, two-thirds of participants were enrolled in studies which included CDC class 2 to 4 surgeries, such as appendectomies and gastrointestinal surgeries. Most participants were adults in a hospital setting. Subcuticular sutures versus transdermal sutures There may be little difference in the incidence of SSI (risk ratio (RR) 1.10; 95% confidence interval (CI) 0.80 to 1.52; 3107 participants; low-certainty evidence). It is uncertain whether subcuticular sutures reduce wound complications (RR 0.83; 95% CI 0.40 to 1.71; 1489 participants; very low-certainty evidence). Subcuticular sutures probably improve patient satisfaction (score from 1 to 10) (at 30 days; MD 1.60, 95% CI 1.32 to 1.88; 290 participants; moderate-certainty evidence). Wound closure time is probably longer when subcuticular sutures are used (MD 5.81 minutes; 95% CI 5.13 to 6.49 minutes; 585 participants; moderate-certainty evidence). Subcuticular sutures versus skin staples There is moderate-certainty evidence that, when compared with skin staples, subcuticular sutures probably have little effect on SSI (RR 0.81, 95% CI 0.64 to 1.01; 4163 participants); but probably decrease the incidence of wound complications (RR 0.79, 95% CI 0.64 to 0.98; 2973 participants). Subcuticular sutures are associated with slightly higher patient satisfaction (score from 1 to 5) (MD 0.20, 95% CI 0.10 to 0.30; 1232 participants; high-certainty evidence). Wound closure time may also be longer compared with staples (MD 0.30 to 5.50 minutes; 1384 participants; low-certainty evidence). Subcuticular sutures versus tissue adhesives, surgical tapes and zippers There is moderate-certainty evidence showing no clear difference in the incidence of SSI between participants treated with subcuticular sutures and those treated with tissue adhesives (RR 0.77, 95% CI 0.41 to 1.45; 869 participants). There is also no clear difference in the incidence of wound complications (RR 0.62, 95% CI 0.35 to 1.11; 1058 participants; low-certainty evidence). Subcuticular sutures may also achieve lower patient satisfaction ratings (score from 1 to 10) (MD -2.05, 95% CI -3.05 to -1.05; 131 participants) (low-certainty evidence). In terms of SSI incidence, the evidence is uncertain when subcuticular sutures are compared with surgical tapes (RR 1.31, 95% CI 0.40 to 4.27; 354 participants; very low-certainty evidence) or surgical zippers (RR 0.80, 95% CI 0.08 to 8.48; 424 participants; very low-certainty evidence). There may be little difference in the incidence of wound complications between participants treated with subcuticular sutures and those treated with surgical tapes (RR 0.90, 95% CI 0.61 to 1.34; 492 participants; low-certainty evidence). It is uncertain whether subcuticular sutures reduce the risk of wound complications compared with surgical zippers (RR 0.55, 95% CI 0.15 to 2.04; 424 participants; very low-certainty evidence). It is also uncertain whether it takes longer to close a wound with subcuticular sutures compared with tissue adhesives (MD -0.34 to 10.39 minutes; 895 participants), surgical tapes (MD 0.74 to 6.36 minutes; 169 participants) or zippers (MD 4.38 to 8.25 minutes; 424 participants) (very low-certainty evidence). No study reported results for patient satisfaction compared with surgical tapes or zippers.

AUTHORS' CONCLUSIONS

There is no clear difference in the incidence of SSI for subcuticular sutures in comparison with any other skin closure methods. Subcuticular sutures probably reduce wound complications compared with staples, and probably improve patient satisfaction compared with transdermal sutures or staples. However, tissue adhesives may improve patient satisfaction compared with subcuticular sutures, and transdermal sutures and skin staples may be quicker to apply than subcuticular sutures. The quality of the evidence ranged from high to very low; evidence for almost all comparisons was subject to some limitations. There seems to be no need for additional new trials to explore the comparison with staples because there are high-quality studies with large sample sizes and some ongoing studies. However, there is a need for studies exploring the comparisons with transdermal sutures, tissue adhesives, tapes and zippers, with high-quality studies and large sample sizes, including long-term assessments.

Enhanced osteogenic proliferation and differentiation of human adipose-derived stem cells on a porous n-HA/PGS-M composite scaffold

This study explored the applicability, cellular efficacy, and osteogenic activities of porous nano-hydroxyapatite/Poly (glycerol sebacate)-grafted maleic anhydride (n-HA/PGS-g-M) composite scaffolds. Nuclear magnetic resonance (NMR) analyses indicated that approximately 43% of the hydroxide radicals in PGS were displaced by maleic anhydride. Resonance bands at 1036 cm^-1 occurred in scaffolds containing nHA powders, and peak areas increased when n-HA weight increased in PGS-M-n-HA-0.4, PGS-M-n-HA-0.5, and PGS-M-n-HA-0.6 scaffolds. The n-HA/PGS-g-M composite scaffolds exhibited porous microstructure with average pore size of 150-300 µm in scanning electron microscopy (SEM) analysis. Differential scanning calorimetry (DSC) identified the glass transition temperature (Tg) as -25-30 °C, indicative of quality resilience. The modulus of compressibility increased when n-HA content increased. Interestingly, viability of human adipose-derived stem cells (hADSCs) in vitro and expression of the osteogenic related genes RUNX2, OCN, and COL1A1 was enhanced in the n-HA/PGS-g-M composite scaffolds compared to those factors observed in PGS-g-M scaffolds. Finally, simulated body fluid (SBF) tests indicated more apatite deposits on the surface of n-HA/PGS-g-M scaffolds compared to PGS-g-M scaffolds. Overall, porous n-HA/PGS-g-M composite scaffolds possessed acceptable biocompatibility and mechanical properties, and they stimulated hADSC cell proliferation and differentiation. Given these qualities, the composite scaffolds have potential applications in bone tissue engineering.

In situ accurate deposition of electrospun medical glue fibers on kidney with auxiliary electrode method for fast hemostasis

An auxiliary electrode electrospinning method is proposed to deposit N-octyl-2-cyanoacrylate (NOCA) medical glue fibrous membrane on kidney for in-situ fast hemostasis. A metal electrode equipped to the spinning needle is used to confine the divergence angle of jet. Compared to the conventional electrospinning method, the fiber deposition area has reduced by 2.5 times, and it can achieve in-situ accurate deposition. Moreover, it reduces both the external dimension and over-reliance on electricity, which is superior to previous air-flow assisted electrospinning method. In addition, in situ accurate deposition of NOCA on the kidney exhibits fast hemostasis within 10 s, confirming that this auxiliary electrode method can be applied in outdoors for fast hemostasis. Further pathological studies indicate that this auxiliary electrode method can reduce the inflammatory response of tissues due to the better accurate deposition. This portable hand-held device with the auxiliary electrode method may have potential application in fast hemostasis for outdoors due to its accurate deposition and portability characteristics.

A US hospital budget impact analysis of a skin closure system compared with standard of care in hip and knee arthroplasty

Background

Medicare’s mandatory bundle for hip and knee arthroplasty necessitates provider accountability for quality and cost of care to 90 days, and wound closure may be a key area of consideration. The DERMABOND^® PRINEO^® Skin Closure System (22 cm) combines a topical skin adhesive with a self-adhering mesh without the need for dressing changes or suture or staple removal. This study estimated the budget impact of the Skin Closure System compared to other wound closure methods for hip and knee arthroplasty.

Methods

A 90-day economic model was developed assuming 500 annual hip/knee arthroplasties for a typical US hospital setting. In current practice, wound closure methods for the final skin layer were set to 50% sutures and 50% staples. In future practice, this distribution shifted to 20% sutures, 20% staples, and 60% Skin Closure System. Health care resources included materials (eg, staplers, steri-strips, and traditional/barbed sutures), standard or premium dressings, outpatient visits, and home care visits. An Expert Panel, comprised of three orthopedic physician assistants, two orthopedic surgeons, and a home health representative, was used to inform several model parameters. Other inputs were informed by national data or literature. Unit costs were based on list prices in 2016 US dollars. Uncertainty in the model was explored through one-way sensitivity and alternative scenario analyses.

Results

The analysis predicted that use of Skin Closure System in the future practice could achieve cost savings of $56.70 to $79.62 per patient, when standard or premium wound dressings are used, respectively. This translated to an annual hospital budgetary savings ranging from $28,349 to $39,809 when assuming 500 arthroplasties. Dressing materials and postoperative health care visits were key model drivers.

Conclusions

Use of the Skin Closure System may provide cost savings within hip and knee arthroplasties due to decreases in resource utilization in the postacute care setting.

Laceration Management

BACKGROUND

Traumatic lacerations to the skin represent a fairly common reason for seeking emergency department care. Although the incidence of lacerations has decreased over the past decades, traumatic cutaneous lacerations remain a common reason for patients to seek emergency department care.

OBJECTIVE

Innovations in laceration management have the potential to improve patient experience with this common presentation.

DISCUSSION

Studies have confirmed that delays in wound closure rarely confer increased rates of infection, although comorbidities such as diabetes, chronic renal failure, obesity, human immunodeficiency virus, smoking, and cancer should be considered. Antibiotics should be reserved for high-risk wounds, such as those with comorbidities, gross contamination, involvement of deeper structures, stellate wounds, and selected bite wounds. Topical anesthetics, which are painless to apply, have a role in select populations. In most studies, absorbable sutures perform similarly to nonabsorbable sutures and do not require revisit for removal. Novel atraumatic closure devices and expanded use of tissue adhesives for wounds under tension further erode the primacy of regular sutures in wound closure. Maintaining a moist wound environment with occlusive dressings is more important than previously thought. Most topical wound agents are of limited benefit.

CONCLUSIONS

Recent innovations in wound closure are allowing emergency physicians to shift toward painless, atraumatic, and rapid closure of lacerations.

Consensus Review of Optimal Perioperative Care in Breast Reconstruction: Enhanced Recovery after Surgery (ERAS) Society Recommendations

BACKGROUND

Enhanced recovery following surgery can be achieved through the introduction of evidence-based perioperative maneuvers. This review aims to present a consensus for optimal perioperative management of patients undergoing breast reconstructive surgery and to provide evidence-based recommendations for an enhanced perioperative protocol.

METHODS

A systematic review of meta-analyses, randomized controlled trials, and large prospective cohorts was conducted for each protocol element. Smaller prospective cohorts and retrospective cohorts were considered only when higher level evidence was unavailable. The available literature was graded by an international panel of experts in breast reconstructive surgery and used to form consensus recommendations for each topic. Each recommendation was graded following a consensus discussion among the expert panel. Development of these recommendations was endorsed by the Enhanced Recovery after Surgery Society.

RESULTS

High-quality randomized controlled trial data in patients undergoing breast reconstruction informed some of the recommendations; however, for most items, data from lower level studies in the population of interest were considered along with extrapolated data from high-quality studies in non-breast reconstruction populations. Recommendations were developed for a total of 18 unique enhanced recovery after surgery items and are discussed in the article. Key recommendations support use of opioid-sparing perioperative medications, minimal preoperative fasting and early feeding, use of anesthetic techniques that decrease postoperative nausea and vomiting and pain, use of measures to prevent intraoperative hypothermia, and support of early mobilization after surgery.

CONCLUSION

Based on the best available evidence for each topic, a consensus review of optimal perioperative care for patients undergoing breast reconstruction is presented.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Evidence-Based Scar Management: How to Improve Results with Technique and Technology

BACKGROUND

Scars represent the visible sequelae of trauma, injury, burn, or surgery. They may induce distress in the patient because of their aesthetically unpleasant appearance, especially if they are excessively raised, depressed, wide, or erythematous. They may also cause the patient symptoms of pain, tightness, and pruritus. Numerous products are marketed for scar prevention or improvement, but their efficacy is unclear.

METHODS

A literature review of high-level studies analyzing methods to prevent or improve hypertrophic scars, keloids, and striae distensae was performed. The evidence from these articles was analyzed to generate recommendations. Each intervention's effectiveness at preventing or reducing scars was rated as none, low, or high, depending on the strength of the evidence for that intervention.

RESULTS

For the prevention of hypertrophic scars, silicone, tension reduction, and wound edge eversion seem to have high efficacy, whereas onion extract, pulsed-dye laser, pressure garments, and scar massage have low efficacy. For the treatment of existing hypertrophic scars, silicone, pulsed-dye laser, CO2 laser, corticosteroids, 5-fluorouracil, bleomycin, and scar massage have high efficacy, whereas onion extract and fat grafting seem to have low efficacy. For keloid scars, effective adjuncts to excision include corticosteroids, mitomycin C, bleomycin, and radiation therapy. No intervention seems to have significant efficacy in the prevention or treatment of striae distensae.

CONCLUSION

Although scars can never be completely eliminated in an adult, this article presents the most commonly used, evidence-based methods to improve the quality and symptoms of hypertrophic scars, as well as keloid scars and striae distensae.

Use of Adipose-Derived Stem Cells to Support Topical Skin Adhesive for Wound Closure: A Preliminary Report from Animal In Vivo Study

The aim of this study was to determine the local and systemic effects of adipose-derived stem cells (ADSCs) as a component of topical skin adhesive in an animal artificial wound closure model. In presented study the cosmetic effects, histological analysis, mechanical properties, and cell migration have been assessed to evaluate the usefulness of ADSCs as supporting factor for octyl blend cyanoacrylate adhesive. The total of 40 rats were used and divided into six groups. In the Study Group, ADSCs were administered by multipoint injection of the six surrounding intrawound areas with additional freely leaving procedure of the cells between the skin flaps just before applying adhesive to close the wound. Five control groups without using ADSCs, utilizing different types of standard wound closure, were created in order to check efficiency of experimental stem cell therapy. In our study, we proved that ADSCs could be used effectively also as a supportive tool in topical skin adhesive for wound closure. However we did not achieve any spectacular differences related to such aspects as better mechanical properties or special biological breakthroughs in wound healing properties. The use of stem cells, especially ADSCs for wound closure can provide an inspiring development in plastic and dermatologic surgery.

Update on Postsurgical Scar Management

Postoperative scar appearance is often a significant concern among patients, with many seeking advice from their surgeons regarding scar minimization. Numerous products are available that claim to decrease postoperative scar formation and improve wound healing. These products attempt to create an ideal environment for wound healing by targeting the three phases of wound healing: inflammation, proliferation, and remodeling. With that said, preoperative interventions, such as lifestyle modifications and optimization of medical comorbidities, and intraoperative interventions, such as adherence to meticulous operative techniques, are equally important for ideal scarring. In this article, the authors review the available options in postoperative scar management, addressing the benefits of multimodal perioperative intervention. Although numerous treatments exist, no single modality has been proven superior over others. Therefore, each patient should receive a personalized treatment regimen to optimize scar management.

Structural and mechanical characterization of bioresorbable, elastomeric nanocomposites from poly(glycerol sebacate)/nanohydroxyapatite for tissue transport applications

Poly(glycerol sebacate) (PGS)/nanohydroxyapatite (nHA) composites were assessed to develop new materials for closure via tissue transport for nonhealing defects (e.g., cleft palate and large skin wounds). The elastic shape memory polymer, PGS, was reinforced with nHA at 3 and 5% loading to increase the mechanical properties compared with the undoped PGS. Differential scanning calorimetry (DSC) was utilized to identify a glass transition temperature (Tg ) of -25°C. X-ray diffraction demonstrated a reduction in the amorphous nature of the material. The Fourier transform infrared photoacoustic spectral (FTIR-PAS) data showed decreased CO bonding and increased hydrogen bonding with increased nHA incorporation. Composites exhibited Young's moduli in the range of 0.25-0.5 MPa and tensile strength of 1.5-3 N. No significant difference in extension to break (∼50 mm) with addition of nHA was observed. The elastic modulus significantly increased for 5% PGS/nHA compared to 0 and 3% PGS/nHA and tensile strength significantly increased for 3% PGS/nHA compared to 0 and 5% PGS/nHA. Degradation of 5% nHA/PGS significantly increased during the second week compared to PGS 0 and 3% PGS/nHA. The accelerated degradation for 5% PGS/nHA coupled with decreased flexibility and tensile strength implies an interruption in crosslinking. By maintaining flexibility and extension while increasing tensile strength, the 3% PGS/nHA doped satisfied the force range desired for closure of soft tissue defects. Based on this work, PGS with 3% nHA shape memory polymers should serve as a good candidate for closure of nonhealing soft tissues. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1366-1373, 2016.