Combining topical dermal infused exosomes with injected calcium hydroxylapatite for enhanced tissue biostimulation.

BACKGROUND: Exosome research continues to flourish. Subsequent knowledge surrounding indications, dose-response, safety, efficacy, and the ability to combine exosome treatment as a "skin primer"-for biostimulation modalities such as calcium hydroxylapatite (CaHA), platelet-rich plasma (PRP), and platelet-rich fibrin matrix (PRFM) is growing rapidly. The objective of this study was to develop safe, reproducible methods of improving topical exosome absorption to enhance the quality of skin either by themselves, or in combination with injectable CaHA. METHODS: Under IRB Approval (International Cell Surgical Society: ICSS-2022-007), 40 patients were enrolled in this study. Twenty patients underwent facial biostimulatory dermal infusion alone, to determine if this method allowed adequate exosome absorption. Five patients underwent facial biostimulatory infusion followed immediately by Dilute CaHA injection (1:1 dilution) to the face. Five patients underwent exosome biostimulatory dermal infusion followed immediately by hyperdilute CaHA (dilution 1:4) injection to the neck. Five patients underwent Facial Dilute CaHA injection (1:1 dilution) alone, without dermal infusion. Five patients underwent neck hyperdilute CaHA injection (1:4 dilution) alone, without dermal infusion. All patients had pretreatment Quantificare 3-D photo-documentation and skin analysis (Quantificare, France). In all patients, the skin was first cleansed with a gentle glycolic acid facial wash (Gregory MD). To induce a "homing inflammatory environment" for the exosomes, sea salt exfoliation was performed (SaltFacial®, SaltMed, Cardiff, CA). A nitric oxide-generating serum (N101 Pneuma Nitric Oxide, Austin, TX) was then applied to act as an enhanced vehicle for absorption. A 3 MHz ultrasound (SaltFacial®, SaltMed, Cardiff, CA) was then utilized to further deepen the absorption of the nitric oxide serum. A topical emulsion containing equal volumes (1.0 cc containing 1 million) of exosomes (Kimera Labs, Miramar, FL), 25 units of botulinum toxin (Xeomin, Merz Aesthetics, Raleigh, NC) and hyaluronic acid (Belatero, Merz Aesthetics, Raleigh, NC) was mixed via back-and-forth propulsion in a 3-cc syringe. When adequately mixed, the emulsion was then applied to the treatment areas. The cavitating ultrasound was then used to aid in the absorption of the emulsion. The patients were then treated with high-intensity LED therapy (SaltFacial®, SaltMed, Cardiff, CA), utilizing the collagen restoration preset program of combination red (660 nm) near-infrared (930 nm) wavelength for 20 min. Post-treatment Quantificare analysis was performed at 15 and 30 days after treatment. RESULTS: Without exception, all dermal infusion alone and CaHA injection alone patients showed an improvement in the tone, quality, and texture of their skin. Quantificare results showed consistent improvement in wrinkles, pores, skin evenness, improved vascularity, and a reduction in oiliness and unwanted pigment. When employed as a skin primer prior to injections (CaHA), enhanced and more rapid results were seen. CONCLUSIONS: Biostimulatory dermal infusion can be achieved utilizing topical placental mesenchymal stem cell-derived exosomes. These exosomes can be used alone, or mixed with ancillary ingredients such as botulinum toxin, hyaluronic acid dermal filler, and CaHA to customize and personalize treatments based upon individual patient needs. Topical absorption is enhanced with sea salt exfoliation, a topical nitric oxide-generating serum, and 3 MHz cavitating ultrasound. Post-absorption activity is enhanced with high-intensity LED treatment. The addition of CaHA injections after the topical exosome "priming of the skin" yielded enhanced skin quality faster than exosomes or CaHA alone.

Uso de hidroxiapatita de cálcio no tratamento da dermatoporose / Use of calcium hydroxyapatite in the treatment of dermatoporosis

A dermatoporose é a síndrome de fragilidade cutânea. Acomete principalmente indivíduos acima de 60 anos, com maior prevalência no sexo feminino. Os principais fatores de risco são: envelhecimento, exposição solar intensa e uso de corticoterapia tópica e sistêmica. Se manifesta clinicamente por atrofia cutânea, púrpuras senis, pseudo cicatrizes estrelares e lacerações, podendo evoluir com hematomas dissecantes e infecções graves. Trata-se de uma doença com grande impacto na qualidade de vida dos pacientes e, até o presente momento, não há terapias com resultados satisfatórios. Hidratação, vitamina C tópica e oral, luz intensa pulsada foram algumas das terapêuticas estudadas. A hidroxiapatita de cálcio é um bioestimulador de colágeno composto por microesferas em um veículo de carboximetilcelulose (Radiesse®). Tem sido usada para estimular a produção endógena de colágeno e consequentemente melhorar a qualidade e espessura da pele. Este efeito do produto poderia melhorar o quadro clínico da dermatoporose. O estudo teve como objetivo avaliar a melhora das lesões purpúricas e da atrofia da pele após aplicação de Radiesse® no antebraço de 5 pacientes portadores de dermatoporose no setor de Dermatologia do Hospital do Servidor Público Municipal de São Paulo. Os 5 pacientes foram submetidos a aplicação de Radiesse® nos antebraços e foram avaliadas 45 e 90 dias após o procedimento, o número de lesões purpúricas, grau de atrofia da pele através do teste de pinçamento e realizado comparação fotográfica. Após o tratamento, observou-se melhora do número das lesões purpúricas, melhora da atrofia da pele e melhora da qualidade de pele quando comparada fotograficamente. Dessa forma, o tratamento com Radiesse® mostrou-se promissor, com resultados satisfatórios e com um bom perfil de segurança. Palavras-chave: Dermatoporose. Púrpura senil. Radiesse. Bioestimulador. Tratamento.

Efficacy of NHP66 Bioactive Cage on Patients with Cervical Spine Injury in Short-Track Speed Skating.

BACKGROUND: Short-track speed skating (STSS) is an extreme sport in pursuit of extreme speed and explosive force. In such a sport, once athletes fall down, they are susceptible to serious cervical spine injury (CSI) under the inertia of high-velocity movement. Nanohydroxyapatite/polyamide 66 (NHP66) bioactive cage is a high-tech product of nanotechnology in the medical field in recent years. With a structure similar to that of human cortical bone, NHP66 bioactive cage has extremely high toughness and strength, which tailors to the needs of STSS. OBJECTIVE: This study mainly analyzed the therapeutic effect of NHP66 on patients with CSI in STSS, aiming to provide new opportunities for the treatment of this patient population. METHODS: A total of 51 patients with CSI treated in our hospital were enrolled, including 19 cases of short-track speed skaters (observation group) and 32 cases of car accidents, falls from heights, or collision injuries (control group). The relevant surgical indicators (operation time, intraoperative blood loss, etc.), the incidence of adverse reactions, the Cobb angle of cervical lordosis before and after surgery, and the fusion segment height of the cage were observed and compared between the two groups. Postoperative pain was evaluated by the visual analog scale (VAS), improvement of spinal cord injury was assessed by the American Spinal Cord Injury Association (ASIA) Impairment Scale, and bone fusion, bone subsidence, and other motor functions were assessed by the Japanese Orthopaedic Association (JOA) score rating system. RESULTS: The operation time, intraoperative blood loss, and incidence of adverse reactions in the observation group were significantly lower than those in the control group. The Cobb angle of cervical lordosis and the fusion segment height of cage increased significantly higher in both groups after surgery. In addition, the VAS scores of the observation group 2 h and 3 d after operation were significantly lower than those of the control group. In terms of improvement of spinal cord injury, ASIA and JOA scores in the observation group were significantly higher than those before treatment and in the control group. There was no significant difference in bone fusion activity between the two groups. CONCLUSIONS: In this study, it is found through experiments that NHP66 has higher safety and application value than autogenous iliac bone, confirming that NHP66 can achieve significant results as a cage for anterior cervical decompression and iliac bone graft fusion and internal fixation in short-track speed skaters after CSI.

Comparison of 24-month voice outcomes after injection laryngoplasty with calcium hydroxylapatite or hyaluronic acid in patients with unilateral vocal fold paralysis.

PURPOSE: The objective was to evaluate the long-term voice outcomes in pa-tients with unilateral vocal fold paralysis treated with injection laryngoplasty using either cal-cium hydroxylapatite (CaHA) or hyaluronic acid (HA). METHODS: A single-centre retrospective study was performed. There were 75 patients with dysphonia due to unilateral vocal fold paralysis: injected with CaHA or injected with HA. We analysed Voice Handicap Index-30 (VHI), videostroboscopic images, auditory-perceptual (GRBAS), and acoustic measures (MDVP) in 6, 12, and 24 months after augmentation. RESULTS: The mean change in VHI 24 months after augmentation was 29.14 in the CaHA group, and 22.88 in the HA group. There was an improvement of glottal gap 6, 12, and 24 months after augmentation in both groups. The GRBAS parameters were similar in both groups throughout the whole period. The MDVP pa-rameters decreased 6 and 12 months after augmentation and were similar in both groups. There were 4 patients augmented with CaHA (12.5%) who needed reintervention within 2 years of surgery and another 4 (9.3%) augmented with HA. CONCLUSION: This study demonstrates that there are no long-term differences in voice outcomes or number of reaugmentations for injection laryn-goplasty with CaHA compared to HA.

A Randomized, Evaluator-Blind, Split-Face Study Evaluating the Safety and Efficacy of Calcium Hydroxylapatite for Jawline Augmentation.

INTRODUCTION: Jawline augmentation with calcium hydroxylapatite has not yet been evaluated in a prospective study with a split-face design. This study aims to perform the first randomized controlled, split-face study on the efficacy and safety of calcium hydroxylapatite for jawline augmentation using the needle and cannula technique. OBJECTIVE: To perform the first randomized controlled, split-face study on the efficacy and safety of calcium hydroxylapatite for jawline augmentation using the needle and cannula technique. MATERIALS AND METHODS: This is a single-site, randomized, evaluator-blind trial enrolling a total of 10 healthy subjects with at least Grade 1 (mild) on a 4-point Jawline Scale. One side of the face was randomized to receive 1 to 2 syringes of calcium hydroxylapatite with lidocaine (total of 3 mL) for correction of wrinkles and folds along the jawline using both the cannula and needle method, and a balancing treatment will be performed 1 month later. Blinded investigator and subject evaluations will be performed immediately after treatment and at the 30-, 60-, and 90-day visits. RESULTS: Ten subjects were enrolled and completed the trial. There was a improvement in the degree of wrinkling and skin sagging in the 4-point Jawline Scale, with an average of a 1.3-point improvement in the scale on the day of treatment and at the Day 30 visit, which remained improved greater than baseline after 3 months as graded by blinded investigators. The Clinician Global Aesthetic Improvement Score for the treated side versus control, as assessed by blinded investigators, demonstrated a improvement with a 2.3-point improvement on the 5-point scale, and by the final visit on Day 90, most patients had a much improved appearance from baseline. CONCLUSION: This study demonstrates that calcium hydroxylapatite is effective and safe for restoration and augmentation of the jawline using the unique needle and cannula technique.

In Vitro and In Vivo Efficacy of New Composite for Direct Pulp Capping.

OBJECTIVES: To investigate physicochemical properties, dentin bonding, cytotoxicity, and in vivo pulp response of experimental self-adhesive composites tailored to direct pulp capping. MATERIALS AND METHODS: Experimental composites were prepared with beta-tricalcium phosphate and hydroxyapatite nanoparticles adsorbed with simvastatin and glutathione added at 0% (control resin), 1 wt% (Res 1%), and 10 wt% (Res 10%). A commercial light-curable calcium hydroxide (Ca(OH)2) (Ultra-Blend Plus) was used as control material. The physicochemical properties investigated were flexural strength and modulus, calcium release, and degree of conversion. Dentin bonding was assessed by the push-out test. Proliferation and cell counting assays were performed to evaluate in vitro cytotoxicity using fluorescence microscopy. In vivo pulp capping was performed on molars of Wistar rats, which were euthanized after 14 days and evaluated by histological analysis. RESULTS: No statistical difference was observed in flexural strength and cell viability (p > 0.05). Res 10% presented higher modulus than control resin and Ca(OH)2. Also, Res 10% attained statistically higher degree of conversion when compared to other experimental composites. Ca(OH)2 showed higher calcium release after 28 and 45 days of storage, with no statistical difference at 45 days to Res 10%. All experimental composites achieved significantly higher bond strength when compared to Ca(OH)2. While no significant difference was observed in the cell proliferation rates, resins at lower concentrations showed higher cell viability. In vivo evaluation of pulp response demonstrated no pulp damage with experimental composites. CONCLUSIONS: The experimental composite investigated in this study achieved adequate physicochemical properties with minor in vivo pulpal inflammation and proved to be a valuable alternative for direct pulp capping.

Systemic Administration of PTH Supports Vascularization in Segmental Bone Defects Filled with Ceramic-Based Bone Graft Substitute.

Non-unions continue to present a challenge to trauma surgeons, as current treatment options are limited, duration of treatment is long, and the outcome often unsatisfactory. Additionally, standard treatment with autologous bone grafts is associated with comorbidity at the donor site. Therefore, alternatives to autologous bone grafts and further therapeutic strategies to improve on the outcome and reduce cost for care providers are desirable. In this study in Sprague-Dawley rats we employed a recently established sequential defect model, which provides a platform to test new potential therapeutic strategies on non-unions while gaining mechanistic insight into their actions. The effects of a combinatorial treatment of a bone graft substitute (HACaS+G) implantation and systemic PTH administration was assessed by µ-CT, histological analysis, and bio-mechanical testing and compared to monotreatment and controls. Although neither PTH alone nor the combination of a bone graft substitute and PTH led to the formation of a stable union, our data demonstrate a clear osteoinductive and osteoconductive effect of the bone graft substitute. Additionally, PTH administration was shown to induce vascularization, both as a single adjuvant treatment and in combination with the bone graft substitute. Thus, systemic PTH administration is a potential synergistic co-treatment to bone graft substitutes.

Gellan gum/alginate-based Ca-enriched acellular bilayer hydrogel with robust interface bonding for effective osteochondral repair.

The treatment of osteochondral (OC) defects remains challenging because of the lack of economical and feasible therapeutic strategies for OC repair and reconstruction. In this study, we report an integrated bilayer hydrogel with robust interface binding force (40 kPa) by facilitating the diffusion of calcium ions to the secondary crosslink of the bilayer hydrogel, in which gellan gum and sodium alginate acted as the chondral layer, gellan gum and hydroxyapatite acted as subchondral layer. This integrated construct has high cytocompatibility, and can seed with mesenchymal stem cells (MSCs) related to different functional protein expression for cartilage and bone formation, respectively. Furthermore, in the rabbit critical-sized osteochondral defect model (4.0 mm in diameter and 8.0 mm in depth), the calcium enriched hydrogel act as a calcium reservoir, promote neovascularization at week 4, and repair the critical defect at week 8, demonstrating the feasible preparation of an acellular hydrogel for OC repair.

Adverse events following injection laryngoplasty: An analysis of the MAUDE database.

OBJECTIVE: Injection laryngoplasty (IL) is considered safe in both the operating room and clinical setting. However, safety data is limited to single-institution studies with reduced sample sizes. The objective of this study is to examine a national database for adverse events related to IL in an effort to further confirm the safety of this procedure and better characterize potential complications. MATERIALS AND METHODS: Retrospective analysis of the Manufacturer and User Facility Device Experience (MAUDE) database for reported adverse events of IL procedures utilizing calcium hydroxyapatite (CAHA), hyaluronic acid (HA) and carboxymethylcellulose (CMC) implants from 2009 to 2020. RESULTS AND ANALYSIS: We identified 47 reported adverse events. The average patient age was 54 years old. 59.3% of patients were female. Adverse events more frequently involved the use of CAHA compared to HA or CMC (n = 27, 57.4%, n = 13, 27.7% and n = 7, 14.9%, respectively). The most common adverse events were laryngeal edema (n = 18, 39.1%), improper placement of injected material (n = 12, 26.1%), persistent dysphonia (n = 13, 28.3%), and post-injection dysphagia or odynophagia (n = 11, 23.9%). Major events, defined as requiring emergency room treatment, hospitalization, or surgical intervention accounted for 29 (60.4%) of cases. Four cases of edema required intubation, and one patient necessitated a surgical airway. CONCLUSION: Complications arising from IL range from minor events to airway obstruction and may happen with a variety of injectable materials including CAHA, HA and CMC. Few cases of airway obstruction requiring immediate intervention were identified, confirming the safety of IL in both the operative and office setting.

Prospective Clinical Trial Evaluating the Long-Term Safety and Efficacy of Calcium Hydroxylapatite for Chest Rejuvenation.

BACKGROUND: Calcium hydroxylapatite (CaHA) is indicated for correcting moderate-to-severe facial wrinkles and folds. Hyperdilute CaHA is increasingly being used for stimulating neocollagenesis to improve skin quality and firmness. OBJECTIVE: This study assessed long-term effects of hyperdilute CaHA for improving chest wrinkle appearance. METHODS AND MATERIALS: Adult female subjects (N=20) were treated with a 1:2 dilution of CaHA and evaluated at week 6, week 12, day 180, and day 360 using validated Merz Décolletage Scales. A Subject Satisfaction Questionnaire was used to assess overall satisfaction on a scale from 0 (Completely Dissatisfied) to 6 (Completely Satisfied). RESULTS: Subjects achieved significant improvements in baseline Merz Décolletage Scale–Dynamic scores at week 6, after a single treatment (P=0.02), at week 12 (two treatments) (P=0.01), day 180 (P=0.01), and day 360 (P<0.01). Subjects also demonstrated significant improvement in baseline Merz Décolletage Scale–At Rest scores at week 6 (P<0.01), remaining significant at week 12 (P<0.01), day 180 (P<0.01), and day 360 (P<0.01). Subject Satisfaction scores increased from 3.25 at day 180 to 3.59 at day 360 using a 7-point scale. CONCLUSION: Hyperdilute CaHA significantly improves the dynamic and resting appearance of wrinkles of the décolleté. These durable improvements persist for at least 1 year. J Drugs Dermatol. 20(5): doi:10.36849/JDD.5680.

Nerve conduit based on HAP/PDLLA/PRGD for peripheral nerve regeneration with sustained release of valproic acid.

The nerve conduits have been developed for nerve defect repair. However, no artificial conduits have obtained comparable results to autografts to bridge the large gaps. A possible reason for this poor performance may be a lack of sustainable neurotrophic support for axonal regrowth. Previous studies suggested nanocomposite conduits can be used as a carrier for valproic acid (VPA), a common drug that can produce effects similar to the neurotrophic factors. Here, we developed the novel bioabsorbable conduits based on hydroxyapatite/poly d-l-lactic acid (PDLLA)/poly{(lactic acid)-co-[(glycolic acid)-alt-(l-lysine)]} with sustained release of VPA. Firstly, the sustained release of VPA in this conduit was examined by high-performance liquid chromatography. Then Schwann cells were treated with the conduit extracts. The cell metabolic activity and proliferation were assayed by 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2-tetrazolium bromide and bromodeoxyuridine staining. A 10-mm segment of rat sciatic nerve was resected and then repaired, respectively, using the VPA conduit (Group A), the PDLLA conduit (Group B), or the autografts (Group C). Nerve conduction velocities (NCVs), compound muscle action potentials (CMAPs), and histological staining were assayed following the surgery. The cell metabolic activity and proliferation were significantly increased (p < .05) by the extracts from VPA-conduit extract compared to others. NCVs and CMAPs were significantly higher in Groups A and C than Group B (p < .05). The nerve density of Groups A and C was higher than Group B. There was no significant difference between Groups A and C. Taken together, this study suggested the sustained-release VPA conduit promoted peripheral nerve regeneration that was comparable to the autografts. It holds potential for future use in nerve regeneration.

Security and reliability of CUSTOMBONE cranioplasties: A prospective multicentric study.

BACKGROUND: Repairing bone defects generated by craniectomy is a major therapeutic challenge in terms of bone consolidation as well as functional and cognitive recovery. Furthermore, these surgical procedures are often grafted with complications such as infections, breaches, displacements and rejections leading to failure and thus explantation of the prosthesis. OBJECTIVE: To evaluate cumulative explantation and infection rates following the implantation of a tailored cranioplasty CUSTOMBONE prosthesis made of porous hydroxyapatite. One hundred and ten consecutive patients requiring cranial reconstruction for a bone defect were prospectively included in a multicenter study constituted of 21 centres between December 2012 and July 2014. Follow-up lasted 2 years. RESULTS: Mean age of patients included in the study was 42±15 years old (y.o), composed mainly by men (57.27%). Explantations of the CUSTOMBONE prosthesis were performed in 13/110 (11.8%) patients, significantly due to infections: 9/13 (69.2%) (p<0.0001), with 2 (15.4%) implant fracture, 1 (7.7%) skin defect and 1 (7.7%) following the mobilization of the implant. Cumulative explantation rates were successively 4.6% (SD 2.0), 7.4% (SD 2.5), 9.4% (SD 2.8) and 11.8% (SD 2.9%) at 2, 6, 12 and 24 months. Infections were identified in 16/110 (14.5%): 8/16 (50%) superficial and 8/16 (50%) deep. None of the following elements, whether demographic characteristics, indications, size, location of the implant, redo surgery, co-morbidities or medical history, were statistically identified as risk factors for prosthesis explantation or infection. CONCLUSION: Our study provides relevant clinical evidence on the performance and safety of CUSTOMBONE prosthesis in cranial procedures. Complications that are difficulty incompressible mainly occur during the first 6 months, but can appear at a later stage (>1 year). Thus assiduous, regular and long-term surveillances are necessary.

Synthetic Bone Graft versus Autograft Obtained from the Spinous Process in Posterior Lumbar Interbody Fusion.

AIM: To compare the clinical and radiological results of using synthetic bone graft versus autograft obtained from the spinous process in posterior lumbar interbody fusion. MATERIAL AND METHODS: This retrospective study included 102 patients with degenerative lumbar spondylolisthesis who underwent one-segment posterior lumbar interbody fusion (PLIF) followed by one-segment posterior transpedicular instrumentation. PLIF surgery was performed using a local solid bone graft obtained from the spinous process in group A and using a synthetic solid calcium hydroxyapatite block in group B. The Oswestry Disability Index (ODI), visual analogue scale (VAS) scores, degree of bone formation, intervertebral disc heights at the operation segment, wound infection, and instrumentation complications were compared between the 6-month and 5-year follow-ups. RESULTS: In both groups, ODI and VAS scores significantly improved at the 6-month and 5-year follow-up. Bone formation at both 6 months and 5 years were higher in group A than that in group B, but without a significant difference when compared. Moreover, the difference in maintaining the intervertebral disc heights was not significant between the two groups. Surgical wound infection more commonly occurred in group B, but without significant difference between the two groups, and rod fractures were observed in two patients in group B; however, no metal breakage was observed in group A. CONCLUSION: Successful fusion of the intervertebral space and intervertebral height restoration can be achieved and maintained with an autograft from the patient's spinous processes.

Impact of a toothpaste with microcrystalline hydroxyapatite on the occurrence of early childhood caries: a 1-year randomized clinical trial.

The aim of this trial was to determine whether a toothpaste with microcrystalline hydroxyapatite is not inferior to a fluoride toothpaste in prevention of caries in children. This double-blinded randomized control trial compared two toothpastes regarding the occurrence of caries lesions using International Caries Detection and Assessment System (ICDAS) ≥ code 1 on the primary dentition within 336 days. The test group used a fluoride-free hydroxyapatite toothpaste three times daily while control group used a toothpaste with fluoride. 207 children were included in the intention-to-treat analysis; 177 of them finished the study per protocol. An increase in caries ICDAS ≥ code 1 per tooth was observed in 72.7% of the hydroxyapatite-group (n = 88), compared with 74.2% of the fluoride-group (n = 89). The exact one-sided upper 95% confidence limit for the difference in proportion of participants with ICDAS increase ≥ 1 (-1.4%) was 9.8%, which is below the non-inferiority margin of 20% demonstrating non-inferiority of hydroxyapatite compared to the fluoride control toothpaste. This RCT showed for the first time, that in children, the impact of the daily use of a toothpaste with microcrystalline hydroxyapatite on enamel caries progression in the primary dentition is not inferior to a fluoride control toothpaste (Clinical Trials NCT03553966).

Development and biocompatibility of the injectable collagen/nano-hydroxyapatite scaffolds as in situ forming hydrogel for the hard tissue engineering application.

Injectable hydrogels attract more attention to hard tissue engineering for the fulfilment of the defects with irregular shapes. Therefore, the researchers investigated the biocompatibility and immune response to the injectable PCL-PEG-PCL-Col/nHA hydrogels in a mouse model. The histological examination was done via H&E. The activation of the immune cells was evaluated by using antibodies against the CD68, CD4, and CD8 markers. The expression of CCL-2, BCL-2, IL-10, and CD31 genes was measured. Moreover, serum levels of the ALT, ALP, AST, and Urea were detected. The results of the chemical analysis showed that the collagen and Nano-hydroxyapatite were successfully integrated into the PCL-PEG-PCL hydrogels. The histological examination revealed a delayed biodegradation rate after the addition of the collagen and Nano-hydroxyapatite. No prominent pro-inflammatory response was found at the site of the injection. There are no significant differences in the levels of the CD68 and CD8/CD4 lymphocyte ratio among groups (p > .05). The expression of the CD31, IL-10 was significantly increased in the PCL-PEG-PCL-Col/nHA hydrogel (p < .05). ALT, ALP, AST, and Urea levels were not altered pre- and post-transplantation of the hydrogels (p > .05). These in vivo results demonstrated that the injectable PCL-PEG-PCL-Col/nHA hydrogels are biocompatible and suitable for further research in hard tissue regeneration.

Are Hydroxyapatite-Coated Screws a Good Option for Sacroiliac Joint Stabilization? A Prospective Outcome Study.

OBJECTIVE: This is a single-surgeon series to prospectively evaluate the clinical and radiologic results of sacroiliac joint (SIJ) stabilization using hydroxyapatite (HA)-coated, fully threaded screws in patients with SIJ dysfunction. METHODS: A total number of 40 patients underwent percutaneous SIJ stabilization using HA-coated screws between 2013 and 2015 at the University Hospital of LLandough with an age range of 33-84 years. Patients were followed up closely, and outcome scores were collected preoperative and 12 months after surgery. Preoperative and postoperative outcomes were evaluated using patient-reported outcome measures (PROMs), Short Form-36, Oswestry Disability Index, EuroQol-5D-5L, and Majeed Pelvic Scores. RESULTS: Thirty-three patients (8 male and 32 female) out of the 40 patients completed follow-up. There was an overall improvement in all PROMs; however, only mental component of SF-36, Oswestry Disability Index, Majeed Pelvic Scores, and EuroQol-5D-5L were statistically significant. Twenty-one patients (63%) had lysis around the screw, and a subgroup analysis showed that improvement in PROMs was significantly less in patients with lysis around the screw. Four patients with lysis around the screw were offered revision due to ongoing pain. Revision was successful in only 1 patient. CONCLUSIONS: Percutaneous SIJ fixation procedure has been shown to have good clinical outcomes, but the use of HA-coated fully threaded screws in this procedure is not recommended on the basis of patient-reported outcome measures and radiologic findings in this prospective study.

Generation of Filler Emboli as a Mechanism for Filler-Related Blindness.

BACKGROUND: Intra-arterial injection of fillers can lead to occlusion of the ophthalmic artery or its branches supplying the retina or the optic nerve. The mechanism through which this occurs is incompletely understood. We investigated the possibility of generating microparticles after injecting commercially available fillers into a flowing system in vitro. METHODS: Three hyaluronic acid fillers and one calcium hydroxylapatite filler were injected into an artificial saline flow system mimicking arterial systolic blood pressure and corresponding to the diameter of the facial artery. All the saline at the end of the tube was collected, centrifuged, and inspected for filler particles. RESULTS: After injection into the system, all fillers immediately disintegrated into small particles that were carried downstream with the flow of the saline. The saline at the end of the tube contained collections of filler. CONCLUSION: Hyaluronic acid and hydroxylapatite fillers break up into small particles immediately after injection into a flowing system, generating emboli rather than a column of filler. The results of this study lead us to hypothesize another potential mechanism leading to filler-related blindness.

Impact of Vertical Stiffness Gradient on the Maximum Divergence Angle.

INTRODUCTION: During vocal fold vibration, the medial surface of both folds forms a convergent shape during opening and a divergent shape during closing. A greater maximum divergence angle is associated with greater closing forces which will increase the closing speed of the glottis. An increased closing speed results in a greater acoustic intensity and greater vocal efficiency. Indentation testing showed that as the strain increases, the inferior aspect of the folds becomes stiffer than the superior aspect, resulting in the vertical stiffness gradient (VSG). We hypothesize that a reduction of the vertical stiffness gradient will reduce the maximum divergence angle. METHODS: Four excised canine larynges were tested. Stress-strain curves of the superior and inferior aspects of the fold in the mid membranous plane of the baseline larynges were taken using the indentation method. Calcium hydroxylapatite (CaHA) crystals were then injected into the superior aspect of the fold. The stress-strain tests were repeated. Particle imaging velocimetry (PIV) of the intraglottal velocity fields was performed in three larynges at different subglottal pressures in the mid coronal plane for the baseline and CaHA-injected larynges. RESULTS: CaHA injection reduced the inferior-superior stiffness gradient in all larynges. The maximal divergence angle was markedly reduced. In some cases, there was not a divergent angle. DISCUSSION: Marked reduction of the vertical stiffness gradient significantly reduces the maximum divergence angle. Clinical implications will be discussed. LEVEL OF EVIDENCE: NA Laryngoscope, 131:E1934-E1940, 2021.