Ear Cartilage Research Articles

Implanted cartilaginous grafts following rhinoplasty: A retrospective histopathological study.

To describe histopathological features of rhinoplasty-related implanted cartilages, 83 cartilages surgically removed from 42 patients (2 men and 40 women) with a median age of 28.0 years (range, 21-47 years) following correction/revision rhinoplasty were examined. These cartilages included 16 autologous costal cartilages (ACCs), 14 irradiated homologous costal cartilages (IHCCs), 24 autologous nasal cartilages (ANCs), 2 irradiated homologous nasal cartilages (IHNCs), 14 autologous ear cartilages (ECs) and 13 combined cartilaginous grafts. The median chondrocytic viability in ACCs (35.9%) was higher than that of IHCCs (0.0%) and ECs (21.4%) (both, P<0.001), and showed no significant differences compared with the viability in ANCs (41.3%) (P=0.455). The median organized rate of chondroid matrix in ACCs, IHCCs, ANCs and ECs was 2.5, 1.4, 0.9 and 2.0%, respectively, and there were no significant differences among them (P=0.909). The present study revealed not only enlarged chondrocytic lacunae, chondrocytic cloning and binucleated/trinucleated chondrocytes, but also a possible transition between chondrocytes and fibroblasts in 6 ACCs, 3 ANCs and 1 EC, lipomembranous fat necrosis (LFN)-like bodies in 15 ACCs, 14 IHCCs, 3 ANCs and 5 ECs, and chondrocytic vacuolar changes in 15 ACCs, 22 ANCs, 2 IHNCs and 16 ECs. A histological transition between LFN-like bodies and chondrocytic vacuoles was focally observed in 2 ACCs and 1 ANC. The present findings suggested that the stability of implanted cartilage did not depend on chondrocytic viability only. Viable chondrocytes preserve implanted chondroid matrix, but also may, in part, induce organization through their transformation into fibroblasts. LFN-like bodies are considered to be an underrecognized form of vacuolar change-related chondrocytic necrosis.

Sodium Carboxymethylcellulose Serves as Sustained-Release Agents for Providing Analgesia at the Donor Site After Costal Cartilage Harvesting in Ear Reconstruction.

The postoperative pain experienced at the donor site following ear reconstruction using autologous costal cartilage significantly impacts patients' quality of life. Sodium carboxymethylcellulose demonstrates a favorable sustained release property, and its potential to prolong the analgesic effect of ropivacaine remains unexplored. The present study aimed to investigate the analgesic efficacy of ropivacaine gel formulated with sodium carboxymethylcellulose as a sustained-release agent on the donor site of costalcartilage. A retrospective analysis was conducted on a total of 75 patients who underwent costal cartilage ear reconstruction. The patients were divided into three groups based on the different analgesic methods applied to the cartilage donor site: ropivacaine solution group, ropivacaine gel group, and ropivacaine solution combined with gel group. The visual analog scale (VAS) and patient-controlled analgesia (PCA) were used to evaluate the severity of chest pain. The study included a total of 60 patients undergoing ear reconstruction, with 20 patients in each group. The VAS chest pain score and the frequency of PCA application were lower in both the ropivacaine gel group and the ropivacaine solution combined with gel group compared to the ropivacaine solution group. There was no significant difference observed between the ropivacaine gel group and the ropivacaine solution combined with gel group. The utilization of sodium carboxymethyl cellulose as a sustained-release agent in the formulation of ropivacaine gel has been found to effectively prolong the duration of pain relief and alleviate postoperative discomfort at the donor site following ear reconstruction with costal cartilage harvesting. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Long-Term Surgical Outcomes of Intermediate Cleft Rhinoplasty.

The risk/benefit ratio of operating on the cleft nasal deformity in the period of mixed dentition remains debated. This study characterizes our 18-year experience with intermediate cleft rhinoplasties to add data and nuance to the discussion. We performed a retrospective cohort study of patients who underwent intermediate cleft rhinoplasty from 2006 to 2023. Demographic information and operative details were collected. Primary outcomes were operative complications and need for subsequent rhinoplasty. Three-hundred and forty-two patients undergoing 372 intermediate rhinoplasties were included: 150 (40.3%) with no graft/implant, 165 (44.4%) with iliac crest cartilage graft, 36 (9.7%) with ear cartilage, 19 (5.1%) with a resorbable plate, and 3 (0.8%) with nasal cartilage. Use of iliac crest graft predicted fewer subsequent rhinoplasties independent of age at surgery, age at most recent follow-up, sex, race, syndromic status, cleft severity, intranasal stenting duration, and surgeon (β=-0.234, p=0.012). Employment of a V-Y chondromucosal flap in the unilateral cleft lip group (β=-0.401, p=0.002) and placement of a columellar strut graft in the bilateral cleft lip group (β=-0.450, p=0.028) predicted fewer subsequent rhinoplasties. The proportion of rhinoplasties utilizing iliac crest grafts increased over time (r(372)=0.806, p<0.001). Most (55.0%) patients with follow-up beyond age 18 (n=60) did not require subsequent rhinoplasty. Iliac crest cartilage grafting as a columellar strut in bilateral clefts and a chondromucosal V-Y advancement in unilateral clefts were associated with a decreased need for future rhinoplasty. Further work is needed to understand the risk/benefit ratio, surgical burden, and patient-reported outcomes of intermediate rhinoplasty.

Bat Ear Correction Steps and Outcomes for Better Life Support.

An unusually projecting human ear is known as a prominent ear, otapostasis, or bat ear. It might be both bilateral and unilateral. The scapha and antihelix of the big concha are not well formed. It is the outcome of cartilage deformity that occurred during early ear development in utero. After the child reaches five years old, the abnormality can be corrected at any time. In order to prevent psychological suffering, the procedure should ideally be performed as soon as possible. Otoplasty correction is reshaping the ear cartilage to bring the ear closer to the side of the head. The cartilage is reshaped, but the skin is left in place. Hearing remains unaffected by the operation. It is mainly done for aesthetic reasons. Although they are uncommon, the post-operative consequences from the operation include hematoma development, keloid formation, infection, and asymmetry in the ears. Otoplasty is a cosmetic operation that involves permanent sutures to alter the size, shape, or location of the ear. The main purpose of otoplasty is to treat promin auris, or bulging ears. Promin auris, the principal indication for otoplasty, is the subject of this review. The indications, contraindications, and method utilized in otoplasty are reviewed in this exercise, which also emphasizes the need of pre- and post-operative care for patients having this surgery. Otoplasty results are generally lifelong and will improve the self-confidence. The goals of otoplasties are to make the ears appear more natural in comparison to the head and help with the overall contour of the ears. Final ear surgery results will be visible after a two week recovery period, with small improvements appearing for up to 12 months post-procedure. A proper understanding of the diagnosis, indications, and surgical techniques will lead to positive outcomes in otoplasty.

“Mortise and Tenon Joint” Technique to Improve the Stability of Three-Dimensional Costal Cartilage Framework in Fully Expansion Ear Reconstruction

Objective: For full expansion of ear reconstruction, the stability of a cartilage framework is very important. However, most techniques for framework fabrication focus on three-dimensional structure and adequate projection. Few studies are available on improving the stability of the reconstructed framework. This study introduces a new “mortise and tenon joint” technique to create a more stable framework in fully expansion ear reconstruction. Methods: A total of 137 patients with microtia underwent full expansion ear reconstruction with the “mortise and tenon joint” technique from January 2018 to July 2022. Results: Hematoma was found in 2 patients after the expander was implanted and evacuated timely to save the flap. Ear cartilage framework exposure occurred in 3 patients after the second stage of surgery. The wounds were debridement and covered by a retroauricular fascia flap with a skin graft. No other complications, such as infection, expander exposure, or rupture, were observed. All patients were followed up for 6 to 12 months after ear reconstruction and asked to fill in a form anonymously about their satisfaction with the reconstructed ear. One hundred thirty-four patients (97.8%) were satisfied with the results. Conclusions: In fully expansion ear reconstruction, the “mortise and tenon joint” technique improves not only the stability of the cartilage framework but also the stereoperception of the reconstructed ear. Most patients who underwent the new technique were satisfied with clear contour and delicate substructures of the reconstructed ear, matched skin color, and long-term dimensional stability.

Auricular deformity correction with simultaneous reconstruction of the conchal bowl using autologous ear cartilage for “flat ear”: A novel surgical technique

Backgrounds"Flat ear" is a subtype of Grade II conchal-type microtia characterized by severely underdeveloped conchal bowl. Traditional surgical techniques often rely on autologous costal cartilage, which poses several risks and complications. This study aimed to introduce a novel surgical technique using autologous ear cartilage in auricular deformity correction surgery with simultaneous conchal bowl reconstruction for “flat ear”. MethodsA total of 19 patients were involved in this single-center, retrospective cohort study. All patients underwent the described surgical technique. The data before the surgery, immediately after the surgery, and at the last follow-up were collected, including length, width, perimeter of auricle and depth of conchal bowl. Patient satisfaction was assessed via the Visual Analog Scale (VAS). ResultsThe study included 12 males and 7 females, with an average age of 10.67 ± 3.86 years. Postoperative results showed significant improvements in auricular measurements, with the affected ear achieving near symmetry with the normal ear. The mean conchal bowl depth was restored from a preoperative 4.33±1.78mm to 17.32±1.28mm postoperatively. VAS scores for patient satisfaction increased significantly from 1.44±0.92 preoperatively to 7.72±1.49 postoperatively, with stability observed at the last follow-up. ConclusionThe novel technique offers a promising alternative to traditional costal cartilage-based auricular deformity correction surgery, providing excellent aesthetic outcomes and high patient satisfaction. This approach may expand treatment options for patients with "flat ear" and related auricular deformities, with reduced invasiveness and potential for future auditory rehabilitation.

3D-Printing of retainer for post-otoplasty morphology preservation

Congenital external auricular anomalies necessitate surgical correction for normal ear appearance. Despite high success rates, recurrence is common due to the elasticity of ear cartilage. Postoperative support and stress on the anatomical structures can effectively maintain the surgical results. This study aims to develop a personalized, 3D-printed retainer for post-otoplasty support, utilizing structured light-scanning and stereolithography 3D printing to improve postoperative outcomes with greater accuracy and consistency. Retainers were designed using Rhinoceros software to fit and support the ear based on these models. BioMed Flex 80A Resin was employed for 3D printing the retainers, ensuring biocompatibility and mechanical strength. Mechanical testing was conducted to assess the cured resin&amp;rsquo;s tensile and compressive properties, as well as its stress relaxation behavior. Finite element analysis (FEA) was performed to assess stress distribution and deformation for optimal support. Clinical validation was conducted involving 20 patients wearing the retainer for 8 h daily for a week, with satisfaction measured using the C-QUEST 2.0 scale. Clinical assessments were performed with 20 post-otoplasty patients treated with either a retainer or an external stretching device. The results indicated that high-precision, biocompatible, patient-specific retainers were successfully produced. BioMed Flex 80A Resin demonstrated strong performance under strain and good stress retention. FEA indicated uniform stress distribution and effective support in critical areas, ensuring structural stability. Clinical validation reported high satisfaction rates (85%), with minor issues in comfort and weight, suggesting a need for individualized adjustments. Clinical assessments demonstrated superior performance in maintaining auricular width and helix-mastoid (H-M) distance compared to the external stretching device. The personalized 3D-printed retainer offers a promising solution for post-otoplasty support, providing consistent, effective, and biocompatible results.

Auricular cartilage regeneration using chondroitin sulfate-based hydrogel with mesenchymal stem cells in rabbits.

Cartilage is an avascular and alymphatic tissue that lacks the intrinsic ability to undergo spontaneous repair and regeneration in the event of significant injury. The efficacy of conventional therapies for invasive cartilage injuries is limited, thereby prompting the emergence of cartilage tissue engineering as a possible alternative. In this study, we fabricated three-dimensional hydrogel films utilizing sodium alginate (SA), gelatin (Gel), and chondroitin sulfate (CS). These films were included with Wharton's jelly mesenchymal stem cells (WJ-MSCs) and intended for cartilage tissue regeneration. The hydrogel film that were prepared underwent evaluation using various techniques including scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, assessment of the degree of swelling, degradation analysis, determination of water vapor transmission rate (WVTR), measurement of water contact angle (WCA), evaluation of mechanical strength, and assessment of biocompatibility. The rabbit ear cartilage regeneration by hydrogel films with and without of WJ-MSCs was studied by histopathological investigations during 15, 30, and 60 days. The hydrogel films containing CS exhibited superior metrics compared to other nanocomposites such as better mechanical strength (12.87 MPa in SA/Gel compared to 15.56 in SA/Gel/CS), stability, hydrophilicity, WVTR (3103.33 g/m2/day in SA/Gel compared to 2646.67 in nanocomposites containing CS), and swelling ratio (6.97 to 12.11% in SA/Gel composite compared to 5.03 to 10.90% in SA/Gel/CS). Histopathological studies showed the presence of chondrocyte cells in the lacunae on the 30th day and the complete restoration of the cartilage tissue on the 60th day following the injury in the group of SA/Gel/CS hydrogel containing WJ-MSCs. We successfully fabricated a scaffold composed of alginate, gelatin, and chondroitin sulfate. This scaffold was further enhanced by the incorporation of Wharton's jelly mesenchymal stem cells. Our findings demonstrate that this composite scaffold has remarkable biocompatibility and mechanical characteristics. The present study successfully demonstrated the therapeutic potential of the SA-Gel-CS hydrogel containing WJ-MSCs for cartilage regeneration in rabbits.

A multicrosslinked network composite hydrogel scaffold based on DLP photocuring printing for nasal cartilage repair.

Natural hydrogels are widely employed in tissue engineering and have excellent biodegradability and biocompatibility. Unfortunately, the utilization of such hydrogels in the field of three-dimensional (3D) printing nasal cartilage is constrained by their subpar mechanical characteristics. In this study, we provide a multicrosslinked network hybrid ink made of photocurable gelatin, hyaluronic acid, and acrylamide (AM). The ink may be processed into intricate 3D hydrogel structures with good biocompatibility and high stiffness properties using 3D printing technology based on digital light processing (DLP), including intricate shapes resembling noses. By varying the AM content, the mechanical behavior and biocompatibility of the hydrogels can be adjusted. In comparison to the gelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA) hydrogel, adding AM considerably enhances the hydrogel's mechanical properties while also enhancing printing quality. Meanwhile, the biocompatibility of the multicrosslinked network hydrogels and the development of cartilage were assessed using neonatal Sprague-Dawley (SD) rat chondrocytes (CChons). Cells sown on the hydrogels considerably multiplied after 7 days of culture and kept up the expression of particular proteins. Together, our findings point to GelMA/HAMA/polyacrylamide (PAM) hydrogel as a potential material for nasal cartilage restoration. The photocuring multicrosslinked network ink composed of appropriate proportions of GelMA/HAMA/PAM is very suitable for DLP 3D printing and will play an important role in the construction of nasal cartilage, ear cartilage, articular cartilage, and other tissues and organs in the future. Notably, previous studies have not explored the application of 3D-printed GelMA/HAMA/PAM hydrogels for nasal cartilage regeneration.

Factors Associated With Outcomes of Facial Reconstruction After Mohs Micrographic Surgery.

Retrospective cohort study. To determine patient, defect, and surgical factors associated with facial reconstructive outcomes. Post-Mohs Micrographic Surgery (MMS) facial reconstructions performed at a single institution between 2015-2020 were reviewed. Patient demographics, comorbidities, defect characteristics, type and timing of reconstruction, and postoperative complications and revisions were collected. Data was analyzed with multivariable logistic regressions. 245 defects in 220 patients (median age 66 years, 143 (65%) female) were included. Most were located on the nose (68%), and median size was 3.0cm2 (IQR 1.32-7.5cm2). Defect size over 10cm2 (OR 5.176, 95% CI 1.353-19.808) and two-staged melolabial flaps (OR 4.021, 95% CI 1.525-10.603) were associated with complications after univariate analysis. Nasal tip defects (OR 2.324, 95% CI 1.076-5.019) were associated with minor revisions. Major revisions were associated with nasal sidewall (OR 2.873, 95% CI 1.125-7.336) and tip (OR 2.780, 95% CI 1.145-6.749) defects, ear cartilage grafts (OR 3.373, 95% CI 1.382-8.231), two-staged paramedian forehead flaps (OR 19.273, 95% CI 6.864-54.112), and delayed reconstruction over 14 days (OR 5.727, 95% CI 1.298-25.281). On multivariable analysis, defect size over 10cm2 (aOR 4.972, 95% CI 1.286-19.073) and two-staged melolabial flaps (aOR 4.575, 95% CI 1.628-12.857) were independently associated with complications, while two-staged paramedian forehead flaps (aOR 14.421, 95% CI 3.976-52.310) were independently associated with major revisions. More complex reconstructions with larger defects and interpolated flaps were associated with revision surgery and complications of facial reconstruction following MMS.

A Contemporary Review of Trachea, Nose, and Ear Cartilage Bioengineering and Additive Manufacturing.

The complex structure, chemical composition, and biomechanical properties of craniofacial cartilaginous structures make them challenging to reconstruct. Autologous grafts have limited tissue availability and can cause significant donor-site morbidity, homologous grafts often require immunosuppression, and alloplastic grafts may have high rates of infection or displacement. Furthermore, all these grafting techniques require a high level of surgical skill to ensure that the reconstruction matches the original structure. Current research indicates that additive manufacturing shows promise in overcoming these limitations. Autologous stem cells have been developed into cartilage when exposed to the appropriate growth factors and culture conditions, such as mechanical stress and oxygen deprivation. Additive manufacturing allows for increased precision when engineering scaffolds for stem cell cultures. Fine control over the porosity and structure of a material ensures adequate cell adhesion and fit between the graft and the defect. Several recent tissue engineering studies have focused on the trachea, nose, and ear, as these structures are often damaged by congenital conditions, trauma, and malignancy. This article reviews the limitations of current reconstructive techniques and the new developments in additive manufacturing for tracheal, nasal, and auricular cartilages.

3D Printing of Maturable Tissue Constructs Using a Cell‐Adaptable Nanocolloidal Hydrogel

Abstract3D‐printed cell‐laden hydrogels as tissue constructs show great promise in generating living tissues for medicine. Currently, the maturation of 3D‐printed constructs into living tissues remains challenge, since commonly used hydrogels struggle to provide an ideal microenvironment for the seeded cells. In this study, a cell‐adaptable nanocolloidal hydrogel is created for 3D printing of maturable tissue constructs. The nanocolloidal hydrogel is composed of interconnected nanoparticles, which is prepared by the self‐assembly and subsequent photocrosslinking of the gelatin methacryloyl solutions. Cells can get enough space to grow and migrate within the hydrogel through squeezing the flexible nanocolloidal networks. Meanwhile, the nanostructure can promote the seeded cells to proliferate and produce matrix proteins through mechanotransduction. Using digital light process‐based 3D printing technology, it can rapidly customize cartilage tissue constructs. After implantation, these tissue constructs efficiently matured into cartilage tissues for the articular cartilage defect repair and ear cartilage reconstruction in vivo. The 3D printing of maturable tissue constructs using the nanocolloidal hydrogel shows potential for future clinical applications.

New Method Using Local Affected Cartilage and Flap for the Cleft in Question Mark Ear.

As a rare auricular deformity, despite numerous surgical procedures for correcting moderate-to-severe question mark ears described in past studies, there remains a need to explore a more cost-effective approach. The optimal utilization of ear cartilage and surrounding skin while achieving superior outcomes continues to pose a significant challenge. From 2018 to 2023, twenty-four patients with unilateral question mark ear were enrolled in this study. Seven of them were severe type deformities (absence of lower part of auricle), and seventeen were moderate (only cleft between helix and lobule). All patients were treated with new method using local cartilage and flap without damage in unaffected area. All patients were satisfied with significant improvement of question mark ear and the overall symmetrical appearance. The surgical scar was not obvious. No complications were observed. The follow-up period revealed that the corrective procedure kept producing the symmetrical and cosmetic results. Our new method enables optimal utilization of deformed tissue and surrounding skin, rendering this method effective and reliable for correcting moderate-to-severe question mark ears. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Characterization of Acellular Cartilage Matrix-Sodium Alginate Scaffolds in Various Proportions.

The development of three-dimensional (3D) bioprinting technology has provided a new solution to address the shortage of donors, multiple surgeries, and aesthetic concerns in microtia reconstruction surgery. The production of bioinks is the most critical aspect of 3D bioprinting. Acellular cartilage matrix (ACM) and sodium alginate (SA) are commonly used 3D bioprinting materials, and there have been reports of their combined use. However, there is a lack of comprehensive evaluations on ACM-SA scaffolds with different proportions. In this study, bioinks were prepared by mixing different proportions of decellularized rabbit ear cartilage powder and SA and then printed using 3D bioprinting technology and crosslinked with calcium ions to fabricate scaffolds. The physical properties, biocompatibility, and toxicity of ACM-SA scaffolds with different proportions were compared. The adhesion and proliferation of rabbit adipose-derived stem cells on ACM-SA scaffolds of different proportions, as well as the secretion of Collagen Type II, were evaluated under an adipose-derived stem cell chondrogenic induction medium. The following conclusions were drawn: when the proportion of SA in the ACM-SA scaffolds was <30%, the printed structure failed to form. The ACM-SA scaffolds in proportions from 1:9 to 6:4 showed no significant cytotoxicity, among which the 5:5 proportion of ACM-SA scaffold was superior in terms of adhesiveness and promoting cell proliferation and differentiation. Although a higher proportion of SA can provide greater mechanical strength, it also significantly increases the swelling ratio and reduces cell proliferation capabilities. Overall, the 5:5 proportion of ACM-SA scaffold demonstrated a more desirable biological and physical performance.

Differential Expression of Noncoding RNAs Revealed Enhancer RNA AC016735.2 as a Potential Pathogenic Marker of Congenital Microtia Patients.

Congenital microtia is a complex maxillofacial malformation with various risk factors. This study aimed to find potential pathogenic noncoding RNAs for congenital microtia patients. We collected 3 pairs of residual ear cartilage samples and corresponding normal ear cartilage samples from nonsyndromic congenital microtia patients for microarray experiments. The differentially expressed RNAs were screened, and enrichment analysis and correlation expression analysis were performed to elucidate the function of the differentially expressed genes (DEGs). We further investigated the most significantly differentially expressed long noncoding RNA (lncRNA), AC016735.2, through follow-up analyses including RT-qPCR and Western blotting, to validate its differential expression in residual ear cartilage compared with normal ear cartilage. SiRNA was designed to study the regulatory role of AC016735.2, and cell proliferation experiments were conducted to explore its impact on residual ear chondrocytes. Analysis of the microarray data revealed a total of 1079 differentially expressed RNAs, including 305 mRNAs and x lncRNAs, using a threshold of FC>1.5 and P<0.05 for mRNA, and FC>1.0 and P<0.05 for lncRNA. Enrichment analysis indicated that these genes are mainly involved in extracellular matrix regulation and embryonic development. AC016735.2 showed the highest differential expression among the eRNAs, being upregulated in residual ear cartilage. It acts in cis to regulate the nearby coding gene ZFP36L2, indirectly affecting downstream genes such as BMP4, TWSG1, COL2A1, and COL9A2. Significant differences were observed in the expression of lncRNAs and mRNAs between residual ear cartilage and normal auricular cartilage tissues in the same genetic background of congenital microtia. These differentially expressed lncRNAs and mRNAs may play crucial roles in the occurrence and development of microtia through pathways associated with extracellular matrix regulation and gastrulation. Particularly, AC016735.2, an eRNA acting in cis, could serve as a potential pathogenic noncoding gene.

The Effects of Radial Cartilage Incision on the Growth of Rabbit Ear.

Recently, radial cartilage incision (first-stage) at an early age combined with free auricular composite tissue grafting (second-stage) can effectively correct the concha-type microtia with the moderate or severe folded cartilage in the middle and upper third auricle, but radial cartilage incision's effects on the growth of the ear remain to be determined. The authors aimed to evaluate the effects of radial cartilage incision in young rabbits model. Ten New Zealand white rabbits were included in our experiment. Two ears of each rabbit were divided randomly into two groups. The experimental group was operated with radial cartilage incision, and no intervention was given to the control group. The ear width, length, and perimeter were noted every two weeks. Auricular surface area was noted at 4 and 22 weeks old. The repeated measures ANOVA was used to describe ears' growth trend. A paired-sample's t test is conducted to test whether there are significant differences among the variables through the SPSS25.0 software. The growth tendencies of the ear length, width, and perimeter were observed and analyzed. The growth curves of the experimental ears were similar to that of the control. There was no significant difference in the increased ratio of surface area among the two groups. The cartilage of the experimental ears showed no change in biomechanical properties compared to that of control group. This study shows that radial cartilage incision at an early age does not influence the growth of rabbit ear length, width, perimeter, and surface area and also does not change the biomechanical properties of the cartilage. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Measurement of the Mechanical Impedance of Ear Cartilage and Development of a Coupler for Vibrator Evaluation of Cartilage Conduction Hearing Aids

Cartilage conduction hearing aids (CCHAs) are new devices that have attracted attention in recent years for external auditory canal atresia. In these devices, a vibrator is attached to the ear cartilage to transmit sound through vibration. In this study, we measure the mechanical impedance of the ear concha auriculae, which represents the mechanical load on the vibrator. To evaluate the output of the CCHAs, we develop a coupler simulating the ear cartilage that measures the sound pressure corresponding to the eardrum sound pressure of the normal ear. Consequently, the mechanical impedance of the developed coupler is several times larger than that of the human ear cartilage measured in this study; however, it is an acceptable value considering the difference in the contact area. The output sound pressure of the vibrator with the coupler simulating the ear cartilage roughly simulates the sound pressure in the ear canal with normal hearing (with the ear canal sealed). In this study, the measured mechanical impedance of the human ear cartilage is approximately 20 dB less than that of the mechanical coupler specified in IEC (International Electrotechnical Commission) 60318-6 for the evaluation of the bone conduction vibrator.

Using polypropylene mesh or ear cartilage autograft with mini screws for the treatment of induced cleft hard palate in puppies: A comparative study

Using polypropylene mesh or ear cartilage autograft with mini screws for the treatment of induced cleft hard palate in puppies: A comparative study

Comparison of Polypropylene and Polydioxanone in the Hemitransdomal Suture: A Novel Rabbit Ear Cartilage Model.

Lower lateral cartilage reshaping is one of the basic steps in rhinoplasty. Hemitransdomal suture is frequently used for dome narrowing. Different suture materials can be used for hemitransdomal suture. In this study, we investigated the effectiveness of polypropylene and polydioxanone in hemitransdomal suture by designing a new experimental model in the rabbit ear cartilage. Twelve young adult male New Zealand White rabbits were used. The bipedicled inverted-U-shaped cartilage was elevated in each ear of the rabbits. Two hemitransdomal sutures were applied using 5-0 polypropylene on one ear and 5-0 polydioxanone on the other ear randomly. A 5mm high cartilage mound was created with two hemitransdomal sutures on each side. The sample size was twelve both in the polypropylene group and the polydioxanone group (n=12). All animals were sacrificed after three months. Cartilage mound heights were measured. The samples were examined histologically regarding fibroadipose tissue, inflammation, foreign body granuloma, cartilage degeneration, and the presence of inclusion cyst. Cartilage mound height was significantly higher in the polypropylene group than in the polydioxanone group at the end of the third month [3.75mm (±0.68) vs. 3.03mm (±0.69); p<0.05]. There was no significant difference between the two groups in histological analysis (p>0.05). Polypropylene suture may be more effective in maintaining the shape given to the dome by hemitransdomal sutures in rhinoplasty. No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266.

1064nm Nd:YAG laser promotes chondrocytes regeneration and cartilage reshaping by upregulating local estrogen levels.

Cartilage is frequently used as a scaffolds for repairing and reconstructing body surface organs. However, after successful plastic surgery, transplanted cartilage scaffolds often exhibit deformation and absorption over time. To enhance the shaping stability of cartilage scaffolds and improve patients' satisfaction after reconstructions, we employed the ear folding models in New Zealand rabbits to confirm whether the 1064nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser could promote cartilage reshaping. There was an increase in collagen and aromatase (Cyp19) expression within the ear cartilage after laser treatment. Moreover, we have found that the Cyp19 inhibitor can inhibit the laser's effect on cartilage shaping and reduce collagen and Cyp19 expression. The overall findings suggest that treatment with 1064nm Nd:YAG laser irradiation can enhance estrogen levels in local cartilage tissues by upregulating Cyp19 expression in chondrocytes through photobiomodulation, thereby promoting the proliferation and collagen secretion of chondrocytes to improve cartilage reshaping and stability.