Initial Healing Research Articles

Collagen gel contraction assays: From modelling wound healing to quantifying cellular interactions with three-dimensional extracellular matrices

Cells respond to and actively remodel the extracellular matrix (ECM). The dynamic and bidirectional interaction between cells and ECM, especially their mechanical interactions, has been found to play an essential role in triggering a series of complex biochemical and biomechanical signal pathways and in regulating cellular functions and behaviours. The collagen gel contraction assay (CGCA) is a widely used method to investigate cell–ECM interactions in 3D environments and provides a mechanically associated readout reflecting 3D cellular contractility. In this review, we summarize various versions of CGCA, with an emphasis on recent high-throughput and low-consumption CGCA techniques. More importantly, we focus on the technique of force monitoring during the contraction of collagen gel, which provides a quantitative characterization of the overall forces generated by all the resident cells in the collagen hydrogel. Accordingly, we present recent biological applications of the CGCA, which have expanded from the initial wound healing model to other studies concerning cell–ECM interactions, including fibrosis, cancer, tissue repair and the preparation of biomimetic microtissues.

Nanofiber Topographies Enhance Platelet-Fibrinogen Scaffold Interactions.

The initial contact with blood and its components, including plasma proteins and platelets, directs the body's response to foreign materials. Natural scaffolds of extracellular matrix or fibrin contain fibrils with nanoscale dimensions, but how platelets specifically respond to the topography and architecture of fibrous materials is still incompletely understood. Here, planar and nanofiber scaffolds are fabricated from native fibrinogen to characterize the morphology of adherent platelets and activation markers for phosphatidylserine exposure and α-granule secretion by confocal fluorescence microscopy and scanning electron microscopy. Different fibrinogen topographies equally support the spreading and α-granule secretion of washed platelets. In contrast, preincubation of the scaffolds with plasma diminishes platelet spreading on planar fibrinogen surfaces but not on nanofibers. The data show that the enhanced interactions of platelets with nanofibers result from a higher locally accessible surface area, effectively increasing the ligand density for integrin-mediated responses. Overall, fibrinogen nanofibers direct platelets toward robust adhesion formation and α-granule secretion while minimizing their procoagulant activity. Similar results on fibrinogen-coated polydimethylsiloxane substrates with micrometer-sized 3D features suggest that surface topography could be used more generally to steer blood-materials interactions on different length scales for enhancing the initial wound healing steps.

Evolution of Myocardial Tissue Injury: A CMR Study Over a Decade After STEMI

BackgroundIn patients with a first ST-segment elevation myocardial infarction (STEMI), the multi-annual evolution of myocardial tissue injury parameters, as assessed by cardiac magnetic resonance (CMR), has not yet been described. ObjectivesThis study examined myocardial tissue injury dynamics over a decade after STEMI. MethodsSequential CMR examinations (within the first week after STEMI, and at 4, 12, months, and 9 years thereafter) were conducted in 74 patients with STEMI treated with primary percutaneous coronary intervention. Left ventricular function, infarct size (IS), and microvascular obstruction (MVO) were assessed at all time points. T2∗, T2, and T1 mapping (n = 59) were added at 9-year scan to evaluate the presence of iron and edema within the infarct core, respectively. ResultsIS decreased progressively and significantly between all CMR time points (all P < 0.001), with an average reduction rate of 5.8% per year (IQR: 3.5%-8.8%) and a relative reduction of 49% (IQR: 39%-76%) over a decade. MVO was present in 61% of patients at baseline, but was not present at the follow-up examinations. At 9-year CMR, 17 of 59 (29%) patients showed iron deposition within the infarct core, whereas 82% had persistent edema. Persistent iron and edema were associated with greater IS on any occasion (all P < 0.001), as well as the presence of MVO (P < 0.001). Patients with persistent iron and edema showed a lower relative regression of IS (P = 0.005 and P = 0.032, respectively) and greater end-systolic volumes over a decade (all P < 0.012 and P > 0.023, respectively). A T1 hypointense infarct core without evidence of T2∗ iron deposition (14 of 59 [24%] patients) was attributed to lipomatous metaplasia of the infarct. ConclusionsThe evolution of IS is a dynamic process that extends well beyond the first few months after STEMI. Persistence of iron and edema within the infarct core occurs up to a decade after STEMI and is associated with initial infarct severity and poor infarct healing.

Combinatorial wound healing therapy using adhesive nanofibrous membrane equipped with wearable LED patches for photobiomodulation.

Wound healing is the dynamic tissue regeneration process replacing devitalized and missing tissue layers. With the development of photomedicine techniques in wound healing, safe and noninvasive photobiomodulation therapy is receiving attention. Effective wound management in photobiomodulation is challenged, however, by limited control of the geometrical mismatches on the injured skin surface. Here, adhesive hyaluronic acid–based gelatin nanofibrous membranes integrated with multiple light-emitting diode (LED) arrays are developed as a skin-attachable patch. The nanofibrous wound dressing is expected to mimic the three-dimensional structure of the extracellular matrix, and its adhesiveness allows tight coupling between the wound sites and the flexible LED patch. Experimental results demonstrate that our medical device accelerates the initial wound healing process by the synergetic effects of the wound dressing and LED irradiation. Our proposed technology promises progress for wound healing management and other biomedical applications.

A Comprehensive Review on Wound Dressings and Their Comparative Effectiveness on Healing of Contaminated Wounds and Ulcers

Any accident or operation can result in a wound. In general, bleeding wounds, chronic wound and infectious wounds require special attention for retrieval and wound recovery and management. In the case of germ infection, this is a difficult procedure. The proper management of wound procedures includes initial cleaning, wound healing, infection prevention, germ treatment and dressings. In the process of wound healing and infection prevention, wound dressings play a vital role. A contaminated wound is defined as one that has been exposed to germs and foreign particles but has shown no evidence of infection. Multiple pathogens or infectious organisms are present in the wound, which is known as a chronic wound. This arises frequently in patients who have diabetic feet and pressure ulcers. As a result, diabetes management necessitates a rapid acceleration of foot ulceration. There is no single dressing that can fulfil all of the needs of a patient with an infected foot ulcer or other contaminated wounds. However, each dressing type has a different aid in selecting it. Wound dressings, such as foam and alginates, are very absorbent and useful for wounds that are heavily oozing. As a clinician, he has to deal each and every day with numerous patients with various types of wounds, such as acute, chronic, burn and foot ulcer conditions. Hence, it is very essential and helpful to have proper knowledge about the right type of dressing for a particular wound and also the right time for wound dressings for patients' prognosis from illness. In this present review, we will discuss the various wound dressings and their comparative effectiveness on contaminated wounds and ulcers.

Development and fabrication of co-axially electrospun biomimetic periosteum with a decellularized periosteal ECM shell/PCL core structure to promote the repair of critical-sized bone defects

Periosteum is crucial to the initial healing of bone defects because it provides a stable periosteum-specific microenvironment and abundant osteogenic cells towards bone repair. However, the usage of autologous periosteum is restricted for limited availability. Xenogeneic decellularized periosteum (DP) preserves periosteum-specific cues but the hardly-controlled physicochemical properties render it inconvenient to use widely. Our study aimed to fabricate a tissue-engineered periosteum (TEP) with a continuous periosteum-specifically bioactive surface and tailored physicochemical properties by co-axial electrospinning of poly(ε-caprolactone) (PCL)/periosteal decellularized extracellular matrix (dECM) to promote bone defects healing. Before use, DP was confirmed for effective removal of residual DNA and well preservation of biological components, e.g., collagen and glycosaminoglycans . After optimization of fabrication processes , PCL/dECM co-axially electrospun membrane (PEC) bore an exquisite core-shell structure, which was effectively equipped with composite advantages of dECM and PCL. Notably, PEC stood out in terms of tensile strength and long-term durability within a physiological environment compared to that of the dECM uniaxial electrospun membrane (ECM). Besides, PEC exhibited remarkably better cell proliferation , migration, bio-mineralization, and osteogenic properties as compared to that of the electrospun PCL membrane. Moreover, PEC-TEP could significantly enhance the recovery of critical-sized bone defects in rats than that of PCL-TEP. To the best of our knowledge, biomimetic PEC-TEP was fabricated and used for the first time to repair bone defects. This novel strategy is promising to fabricate a dECM-based advanced membrane for tissue engineering.

Thrombus formation at the inflow cannula of continuous-flow left ventricular assist devices-A systematic analysis.

Despite numerous design iterations, thrombus formation at the inflow cannula of continuous-flow left ventricular assist devices remains an unsolved problem. We systematically investigated the impact of cannula surface on thrombus formation. Thrombus appearance was photographically documented in 177 explanted hearts with the polished (N=46) or sintered (N=131) inflow cannula of the Medtronic HeartWare™ HVAD™ System. Thrombus load was compared for both inflow cannula types. Mean thrombus length was correlated with protruding cannula length. Support duration and the extent of thrombus growth were examined. The prevalence of thrombi at the left ventricular entry site and at the sintered-to-polished transition zone was correlated with left ventricular geometry and hemodynamic parameters. Polished inflow cannulas showed a greater percentage and also a greater mean length of thrombus formation at the entry site than sintered cannulas (91.3% [Pol] vs. 36.7% [sTi]; p<0.0001; mean 7.6mm vs. 1.9mm; p<0.0001). A comparison of the early postoperative period (POD1-90) with long-term support (POD>90) showed an increase in thrombus length originating from the transition zone (1.96±3.41mm vs. 3.03±2.91mm; p=0.013). A sintered titanium surface at the entry site is crucial to enable anchoring of myocardial tissue to the cannula. As thrombus growth progresses on polished surfaces, a greater sintered length seems to be beneficial. After an initial three-month healing period, thrombus load appears to decline during prolonged support duration at the sintered entry site but not at the transition zone.

Evaluation of the efficacy of ipsilateral fibular transfer for reconstruction of large tibial defects in children: a retrospective study

BackgroundReconstruction of large tibial defects is often a major challenge in limb salvage. This study aimed to evaluate initial follow-up results of ipsilateral fibula transfer for the treatment of large tibial defects in children.MethodsA retrospective study was performed between September 2014 and April 2021. Ten children were identified as having large tibial defects. The children underwent ipsilateral fibula transfer. We then evaluated initial healing, tibial length discrepancy, ankle varus/valgus, fibular position, refracture, infection, and function.ResultsFive boys and five girls, with an average age of 7.2 years, were evaluated. The transferred fibula was united in the patients. The mean follow-up period after fibular transposition was 43 months. The patients achieved primary bone union; the mean time to union was 8.4 months (range, 4–18 months). Complications included refracture (30%), infection (40%), tibia malunion (30%), ankle varus (30%), sensory loss of toes (10%), and ankle valgus (10%). No other major complications were observed. All 10 patients were able to perform activities of daily living and return to their normal activities.ConclusionIpsilateral fibula transfer is a salvage surgery for the treatment of large tibial defects in children with congenital pseudoarthrosis of the tibia, traumatic nonunion of the tibia, and/or tibial defect after chronic osteomyelitis. However, long-term results still need to be followed up.

Long-term results of immediate implantation in mandibular posterior teeth with early loading: A retrospective case series

When immediate molar implants first were proposed, submerged initial healing and delayed loading were the norm. It is now recognized that some early loading of a nonocclusal nature can stimulate faster osseointegration, although full occlusal loading is still delayed for 3 or more months. Here, we test the hypothesis that earlier occlusal loading of mandibular premolar and molar immediate implants may be possible. In this retrospective case series study, 18 mandibular molar and nine mandibular premolar teeth were atraumatically extracted and immediate implants placed 1-2 mm apical to buccal and lingual crestal bone. Periimplant gaps received particular allograft covered with acellular dermal matrix barrier. Healing abutments were placed through puncture points in the membranes to help in stabilizing the latter and to permit nonsubmerged site healing. At 6-8 weeks, each implant was evaluated for stability using the Periotest® device and restored if the Periotest® (PTV) value seen was negative. Data were analyzed by t test and MannWhitney U at a significance level of P < 0.05. Retrospective assessment of all 27 implants after 5 years' period of follow up showed all implants to have survived. Overall mean crestal bone loss was determined to be-0.25 ± 0.54 mm. Individual mean bone levels for mesial and distal surfaces were-0.24 ± 0.77 mm and-0.26 ± 0.72 mm, respectively (P = 0.78). A statistically significant difference in bone loss between genders was detected. Overall mean probing depth was 2.09 ± 0.57 mm. Based on the widely used Albrektsson criteria, the overall survival and success rate was 100%. Immediate implants placed into mandibular premolar and molar extraction sockets and allowed nonsubmerged healing may be ready for restoration at earlier times than previously thought possible.

MIF does only marginally enhance the pro-regenerative capacities of DFO in a mouse-osteotomy-model of compromised bone healing conditions.

The initial phase of fracture healing is crucial for the success of bone regeneration and is characterized by an inflammatory milieu and low oxygen tension (hypoxia). Negative interference with or prolongation of this fine-tuned initiation phase will ultimately lead to a delayed or incomplete healing such as non-unions which then requires an effective and gentle therapeutic intervention. Common reasons include a dysregulated immune response, immunosuppression or a failure in cellular adaptation to the inflammatory hypoxic milieu of the fracture gap and a reduction in vascularizing capacity by environmental noxious agents (e.g. rheumatoid arthritis or smoking). The hypoxia-inducible factor (HIF)-1α is responsible for the cellular adaptation to hypoxia, activating angiogenesis and supporting cell attraction and migration to the fracture gap. Here, we hypothesized that stabilizing HIF-1α could be a cost-effective and low-risk prevention strategy for fracture healing disorders. Therefore, we combined a well-known HIF-stabilizer - deferoxamine (DFO) - and a less known HIF-enhancer - macrophage migration inhibitory factor (MIF) - to synergistically induce improved fracture healing. Stabilization of HIF-1α enhanced calcification and osteogenic differentiation of MSCs in vitro. In vivo, only the application of DFO without MIF during the initial healing phase increased callus mineralization and vessel formation in a preclinical mouse-osteotomy-model modified to display a compromised healing. Although we did not find a synergistically effect of MIF when added to DFO, our findings provide additional support for a preventive strategy towards bone healing disorders in patients with a higher risk by accelerating fracture healing using DFO to stabilize HIF-1α.

734 Have I lost my large rupture cavity? The fingerprint of atherosclerotic plaque healing detected by serial optical coherence tomography imaging

Abstract A 64-year-old man, prior smoker, with a history of paroxysmal atrial fibrillation was referred to our hospital due to worsening dyspnoea, progressively worsening angina, and a positive stress EKG testing. Coronary angiography (CAG) showed an angiographically intermediate stenosis of the mid left anterior descending (LAD) artery and a focal, complex lesion of the distal right coronary artery (RCA) (Figure 1A and B, red arrow). Treatment of the LAD stenosis was deferred based on a negative fractional flow reserve value (i.e. 0.85). Optical coherence tomography (OCT) imaging (ILUMIEN OPTIS, Abbott Vascular, Santa Clara, CA) was performed to better characterize the RCA lesion, which disclosed a ruptured thin-cap fibroatheroma (TCFA) with a large ‘empty’ cavity (Figure 1C–G, red arrows) and overlying ‘layered’ tissue (Figure 1H, white arrowheads). Based on these OCT findings, suggestive of initial plaque healing, and on a large residual lumen dimension (i.e. minimum lumen area, MLA, at the rupture site: 7.7 mm2), this lesion was not treated with percutaneous coronary intervention. The patient was discharged on aspirin, edoxaban, metoprolol, rosuvastatin, and ezetimibe, and remained clinically stable for more than 1 year. Due to angina recurrence, a new CAG was performed 18 months after the first admission, revealing a progression of the mid LAD stenosis that was treated with a 2.5/28 mm drug-eluting stent, and an improvement of the RCA lesion angiographic appearance (smooth contour) (Figure 1A′–B′). RCA OCT imaging was repeated demonstrating a complete healing of the large rupture cavity with all the hallmarks of the reparative process (Figure 1C′–H′): (1) re-established fibrous cap integrity and smooth vessel lumen profile; (2) thickening of the fibrous cap and reduction of lipid burden (i.e., transformation of TCFA into thick-cap fibroatheroma, ThCFA); (3) replacement of the ‘empty’ cavity with new ‘granulation tissue’; (4) initial calcification of the plaque; (5) heterogeneous signal-rich layers with distinct optical-signal intensity (layered, ‘onion-like’ pattern); and (6) mild lumen narrowing (MLA at the rupture site: 6.9 mm2).

Unravelling the effect of healing conditions and vulcanizing additives on the healing performance of rubber networks

Self-healing rubbers have steadily been growing during the last decades. Various strategies have been studied to transform the vulcanized rubber into a reversible cross-linked network with multiple repair cycles. However, a detailed description on how the chemical constituents of a rubber formulation affect the healing properties of the vulcanizate is unknown and has not been reported until now. In this research, the individual effects of both the curing agent (sulfur and peroxide) and the activating complex (zinc oxide and stearic acid) have been assessed on the healing capability of a styrene-butadiene rubber (SBR) compound. The analysis of different healing conditions revealed that pristine materials should be subjected to the same thermal treatment as the healed samples to obtain scientifically sound values of the healing efficiency. Results also showed that each component affected the healing at different time scales, with the activating complex being responsible for the initial physical healing stage. Meanwhile, sulfur would act at later stages as dynamic healing moiety, enabling disulfide exchange reactions. In conclusion, the mechanical recovery of a rubber network can be potentially tailored depending on the relation between the chemical components of the rubber formulation.

Biodegradable magnesium barrier membrane used for guided bone regeneration in dental surgery

Barrier membranes are commonly used as part of the dental surgical technique guided bone regeneration (GBR) and are often made of resorbable collagen or non-resorbable materials such as PTFE. While collagen membranes do not provide sufficient mechanical protection of the covered bone defect, titanium reinforced membranes and non-resorbable membranes need to be removed in a second surgery. Thus, biodegradable GBR membranes made of pure magnesium might be an alternative. In this study a biodegradable pure magnesium (99.95%) membrane has been proven to have all of the necessary requirements for an optimal regenerative outcome from both a mechanical and biological perspective. After implantation, the magnesium membrane separates the regenerating bone from the overlying, faster proliferating soft tissue. During the initial healing period, the membrane maintained a barrier function and space provision, whilst retaining the positioning of the bone graft material within the defect space. As the magnesium metal corroded, it formed a salty corrosion layer and local gas cavities, both of which extended the functional lifespan of the membrane barrier capabilities. During the resorption of the magnesium metal and magnesium salts, it was observed that the membrane became surrounded and then replaced by new bone. After the membrane had completely resorbed, only healthy tissue remained. The in vivo performance study demonstrated that the magnesium membrane has a comparable healing response and tissue regeneration to that of a resorbable collagen membrane. Overall, the magnesium membrane demonstrated all of the ideal qualities for a barrier membrane used in GBR treatment.

Advanced platelet-rich fibrin (A-PRF) has an impact on the initial healing of gingival regeneration after tooth extraction

ObjectivesPlatelet-rich fibrin (PRF) is widely used in wound healing because it contains several growth factors, including vascular endothelial growth factor (VEGF). In this study, we investigated the effects of advanced PRF (A-PRF) in early-stage gingival regeneration after tooth extraction. MethodsBlood sample was collected from females beagle dogs (age: 12 months) before tooth extraction for A-PRF preparation. All animals were sacrificed by perfusion-fixation on postoperative days 1, 3, and 7. The upper jaws were prepared for hematoxylin and eosin staining and immunostaining (for CD34 and VEGF). The lower jaw samples were prepared for scanning electron microscope observations. Blood flow in the gingiva before and after surgery was measured using laser Doppler flowmetry. ResultsIn the A-PRF group, a large number of microvessels were observed in the gingival tissue on postoperative day 1. The microvessels in the control group were fewer and sparse. Regarding the vascular resin cast, a large number of new blood vessels were observed on postoperative day 1 in the A-PRF group. A stronger CD34-positive signal was obtained around the blood vessels in the A-PRF group than in the control group. Further, a strong VEGF-positive signal was observed in the perivascular tissue in the A-PRF group. Gingival blood flow was significantly higher in the A-PRF group after surgery. ConclusionA-PRF had a positive impact on angiogenesis in the gingiva through the induction of VEGF expression. Thus, A-PRF may be beneficial for gingival tissue regeneration.

SCALPEL VERSUS DIODE LASER FOR GINGIVAL DEPIGMENTATION: A CASE REPORT

Gingival hyperpigmentation is believed to be a genetic trait in populations and is more appropriately termed physiologic or racial gingival pigmentation a condition, which affects all races differently. Gingival depigmentation is most frequently performed as an esthetic periodontal plastic surgical procedure. There are various procedures like scalpel, laser. Cryosurgery, diamond burs and chemical methods have been used in this procedure. This case report compares the efficacy of two techniques. Maxillary anterior region was treated with scalpel technique and the mandibular anterior region was treated using Diode Laser. Both the treatment modalities were effective in terms of patient acceptance. Scalpel depigmentation resulted in uneventful healing of the treated site. Laser depigmentation showed some beneficial effects like bloodless field during surgical procedure which healed uneventfully. Patient discomfort was more in laser treated site during the initial healing period as compared to scalpel.

Role of mononuclear stem cells and decellularized amniotic membrane in the treatment of skin wounds in rats

ABSTRACT Stem cells (SC) and amniotic membrane (AM) are recognized for their beneficial impacts on the healing of cutaneous wounds. Thus, this study evaluated the capacity of tissue repair in a skin lesion rat model. Forty Wistar rats were randomized into four groups: group I – control, with full-thickness lesions on the back, without SC or AM; group II–injected SC; group III – covered by AM; group IV–injected SC and covered by AM. Lesion closure was assessed using contraction rate (Cr). Histochemical and immunohistochemical analyses were performed, and collagen, elastic fibers, fibroblast differentiation factor (TGF-β), collagen remodeling (MMP-8), and the number of myofibroblasts and blood vessels (α-SMA) were evaluated. On the 7th postoperative day, Cr 1st-7th day levels were higher in groups III and IV. However, on the 28th day, Cr 1st-28th day were higher in the control group. Picrosirius staining showed that type I collagen was predominant in all groups; however, the SC + AM group obtained a higher average when compared to the control group. Elastic fiber analysis showed a predominance in groups that received treatment. Groups II and IV showed the lowest expression levels of TGF-β and MMP-8, and α-SMA was significantly lower in group IV. The application of SC and AM accelerated the initial healing phase, probably owing to their anti-inflammatory effect that favored early formation of collagen and elastic fibers.

Long-term autogenous healing and re-healing performance in concrete: Evaluation using air-coupled surface-wave method

This study aimed at investigating two original topics on self-healing concrete, 1) the prediction of long-term healing progress and 2) the evaluation of re-healing performance for a previously healed but reopened crack, using the air-coupled surface-wave method. Small-scale plate concrete specimens were fabricated with a self-healing binder incorporating ground granulated blast furnace slag, Na2SO4, anhydrite, and graded clinkers. A single flexural crack of 0.25–0.30 mm width was generated near the mid-span of each specimen. Then, the specimens were kept immersed in water, and the healing progress of the cracks was monitored for approximately one year. As a result, the residual surface crack area was reduced to 15.1% of the fully-cracked condition, and the surface wave transmission ratio recovered up to 82.9% of the uncracked condition. A prediction model for the ultimate healing rate and initial healing rate was proposed based on surface-wave results. After the first self-healing process, the specimens were loaded again, and a similar crack was produced at the previously healed zone in each specimen. Then, the re-healing performance was evaluated for about two months. From the second self-healing process, one specimen with a narrow reopened crack showed a satisfactory recovery in surface wave transmission, comparable to that in the first healing.

Is the Low and Short Medial Horizontal Osteotomy a Predictive Factor for Bad Splits in Sagittal Split Osteotomies?

Statement of the problemThe purpose of this study is to determine whether a low and short medial horizontal osteotomy is a predictive factor for determining bad splits in non-syndromic patients undergoing sagittal split osteotomies for dentofacial disorders. Materials and methodsA retrospective cohort analysis was conducted on subjects who received orthognathic surgery from 2017 to 2019 at Parkland Memorial Hospital. Inclusion criteria were a traditional osteotomy defined by Hunsck and Epker or a low and short osteotomy defined by Posnick.1,2 Exclusion criteria were the diagnosis of a syndromic condition, repeat surgery, or concomitant temporomandibular joint surgery. The predictor variable was the type of osteotomy performed, defined as either a low and short or traditional osteotomy. The primary outcome variable was the occurrence of a bad split. Secondary predictor variables were age and sex, defined as male or female, and faculty side (right side) versus resident side (left side). Descriptive, bivariate, and multiple logistic regression analyses were performed with P < .05 used to determine statistical significance. Results and outcomesFifty-nine patients met the defined inclusion criteria. The average age at the time of surgery was 21 years old. The cohort consisted of 27 males and 32 females. Thirty-six patients were treated with bilateral low and short osteotomies, and 23 patients were treated with bilateral traditional osteotomies. Of the 118 total osteotomies performed, there were a total of 9 bad splits (7.6%). There were 3 right-side bad splits and 6 left-side bad splits. The occurrence of a right-side bad split was 3 for the low and short group and 0 for the traditional group. The occurrence of a left-side bad split was 4 for the low and short group and 2 for the traditional group. There were no significant differences between the type of osteotomy performed and the occurrence of a right-side bad split (P = .1607) or a left-side bad split (P = .7695). There was no significant difference between sex and occurrence of a right-side bad split (P = .6640) or a left-side bad split (P = .2862). There was no significant difference between age and occurrence of a right-side bad split (P = .5233) or a left-side bad split (P = .4492). There was no significant difference between faculty side and resident side with regards to bad splits (P = .4903). Discussion and conclusionThe sagittal split osteotomy (SSO) was first reported by Trauner and Obwegeser in 1955, with the horizontal medial osteotomy further modified by Hunsuck to terminate superior and posterior to lingula.1 Posnick developed an additional modification of the SSO to reduce the frequency of unfavorable splits toward the condyle by modifying the medial horizontal osteotomy to terminate below lingula at the level of the mandibular occlusal plane (low) and anterior to lingula (short).2 The occurrence of bad splits using the traditional osteotomy ranges from 1% to 23%, while the incidence of bad splits reported by Posnick in his retrospective analysis was 0%. The results of the present study suggest a low and short osteotomy is at least as reliable as the traditional osteotomy with regards to intraoperative bad splits. Future prospective studies, including split-mouth study designs by this group, will further elucidate the low and short osteotomy as a reliable alternative to the traditional osteotomy.1.The low medial horizontal osteotomy in patients with atypical ramus morphology undergoing sagittal split osteotomy2.Occurrence of a ‘bad’ split and success of initial mandibular healing: a review of 524 sagittal ramus osteotomies in 262 patients

Randomized Controlled Trial Comparing Nylon and Chromic Gut Sutures After Minor Hand Surgery

We sought to compare overall satisfaction with treatment and satisfaction with initial wound healing after closure of office hand and upper extremity surgery wounds using polyamide compared to Chromic gut sutures. We compared 62 patients randomized to polyamide suture closure of an office hand and upper extremity incision (mostly carpal tunnel release and trigger finger release) to 50 patients closed with Chromic gut suture. Patients rated overall treatment satisfaction, satisfaction with initial healing, pain intensity, and upper extremity-specific activity tolerance. Accounting for potential confounding in multivariable linear and logistic regression analysis, we found the following: (1) overall satisfaction with care was unrelated to suture type; (2) satisfaction with initial wound healing and appearance was lower among people with no other comorbidities, but unrelated to suture type; (3) there were no factors independently associated with pain intensity; and (4) excisional biopsy was associated with greater activity tolerance. Our findings suggests that Chromic sutures are a viable alternative to polyamide sutures after office hand surgery, provided that the care team anticipates and develops strategies for concerns that may arise if the sutures take an extended period to fall off. Therapeutic II.

A-38 Post-Intensive Care Syndrome in a Cohort of School-Aged Children &amp; Adolescents Receiving Integrated Care Via a Pediatric Critical Care &amp; Neurotrauma Recovery Program

Abstract Objective We aimed to identify critical issues related to Post-Intensive Care Syndrome (PICS) through an integrated model of care whereby children and families participate in follow-up clinics with a neuropsychologist and a critical care physician. To demonstrate the impact of direct assessment, we present pilot program findings on early identification and treatment of PICS in a cohort of school-aged children and adolescents through a combination of multi-professional direct assessment and parent proxy questionnaires. Method 64 children and adolescents ages 8–17 years participated in the current study. PICS issues related to physical, cognitive, and psychosocial health were screened 1–3 months after discharge from the pediatric intensive care unit (PICU). The primary outcome was nine performance-based neurocognitive measures combined through principal components analysis to create a neurocognitive index (NCI). Pearson correlation (r) was used to determine the NCI association with other PICS measures at the p &amp;lt; 0.05 significance level. Results The NCI accounted for 52% of the overall variance. Better NCI performance was significantly associated with improved quality of life (r = 0.4). Poorer neurocognitive functioning was significantly associated with the presence of intracranial lesions on imaging (r = −0.28), a neurodevelopmental (r = −0.3) or neurocognitive (r = −0.29) disorder clinician diagnosis, and parent-reported sleep disturbances (r = −0.5), fatigue (r = −0.46), and global executive functioning (r = −0.42). Conclusions Performance-based measures of neurocognitive functioning were associated with core PICS features including physical, cognitive, and psychosocial functioning. Direct assessment of neurocognitive and psychosocial functioning in the initial healing phase following PICU admission is needed to provide patients and their families with expedited and comprehensive guidance for recovery.