A novel acrylic orthodontic device for treatment of linguoverted mandibular canine teeth in small dogs.

Linguoverted mandibular canine teeth (LMC) is a common malocclusion in dogs. Several inclined bite-plane techniques using acrylic resin have been introduced to correct LMC in dogs. Although these techniques have suggested modifications to overcome shortcomings, there are still limitations; e.g., high technical sensitivity, as the viscous acrylic resin must still be fabricated in the oral cavity. The authors developed a novel method for small-breed dogs that uses a doughy acrylic resin form to achieve an easy intraoral design and extraoral fabrication. Eight small-breed dogs were presented to evaluate and treat malocclusion causing palatal trauma. First, a Class-1 malocclusion with linguoversion of the mandibular canine teeth (6 dogs with unilateral LMC and 2 dogs with bilateral) was diagnosed based on oral examination. Dogs were treated with the new method using a doughy acrylic resin form for 6 to 7 wk and had posttreatment follow-up 1 y after the procedure. All treated canine teeth were in correct positions 1 y after the appliances were removed. Key clinical message: The authors believe that the new method using a doughy acrylic resin form could be a good alternative for veterinarians to use when treating LMC.

Un nouveau dispositif orthodontique en acrylique pour le traitement des canines mandibulaires linguoverties chez les petits chiens. Les canines mandibulaires linguoverties (LMC) sont une malocclusion courante chez le chien. Plusieurs techniques de plan de morsure incliné utilisant de la résine acrylique ont été introduites pour corriger la LMC chez le chien. Bien que ces techniques aient suggéré des modifications pour surmonter les lacunes, elles présentent encore des limites; par exemple, une sensibilité technique élevée, car la résine acrylique visqueuse doit encore être fabriquée dans la cavité buccale. Les auteurs ont développé une nouvelle méthode pour les chiens de petite race qui utilise une forme pâteuse de résine acrylique pour obtenir une conception intra-orale et une fabrication extra-orale faciles. Huit chiens de petite race ont été présentés pour évaluer et traiter une malocclusion provoquant un traumatisme palatin. Tout d'abord, une malocclusion de classe 1 avec linguoversion des canines mandibulaires (6 chiens avec LMC unilatérale et 2 chiens avec bilatérale) a été diagnostiquée sur la base d'un examen oral. Les chiens ont été traités avec la nouvelle méthode en utilisant une forme pâteuse de résine acrylique pendant 6 à 7 semaines et ont fait l'objet d'un suivi post-traitement 1 an après la procédure. Toutes les canines traitées étaient dans la bonne position un an après le retrait des appareils.Message clinique clé:Les auteurs estiment que la nouvelle méthode utilisant une forme pâteuse de résine acrylique pourrait être une bonne alternative que les vétérinaires pourraient utiliser lors du traitement du LMC.(Traduit par Dr Serge Messier).

Synergistic Effect, Improved Cell Selectivity, and Elucidating the Action Mechanism of Antimicrobial Peptide YS12.

Antimicrobial peptides (AMPs) have attracted considerable attention as potential substitutes for traditional antibiotics. In our previous research, a novel antimicrobial peptide YS12 derived from the Bacillus velezensis strain showed broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria. In this study, the fractional inhibitory concentration index (FICI) indicated that combining YS12 with commercial antibiotics produced a synergistic effect. Following these findings, the combination of YS12 with an antibiotic resulted in a faster killing effect against bacterial strains compared to the treatment with the peptide YS12 or antibiotic alone. The peptide YS12 maintained its antimicrobial activity under different physiological salts (Na+, Mg2+, and Fe3+). Most importantly, YS12 exhibited no cytotoxicity towards Raw 264.7 cells and showed low hemolytic activity, whereas positive control melittin indicated extremely high toxicity. In terms of mode of action, we found that peptide YS12 was able to bind with LPS through electrostatic interaction. The results from fluorescent measurement revealed that peptide YS12 damaged the integrity of the bacterial membrane. Confocal laser microscopy further confirmed that the localization of peptide YS12 was almost in the cytoplasm of the cells. Peptide YS12 also exhibited anti-inflammatory activity by reducing the release of LPS-induced pro-inflammatory mediators such as TNF-α, IL-1ß, and NO. Collectively, these properties strongly suggest that the antimicrobial peptide YS12 may be a promising candidate for treating microbial infections and inflammation.

Treatment of two Asiatic black bears (Ursus thibetanus) with severe injuries and their subsequent release into the wild: a case report.

BACKGROUND: The rehabilitation of injured wildlife and their subsequent release into the wild is a humane act as well as important in wildlife conservation. However, little is known about the animals' fate after release. Therefore, to address these uncertainties, it is essential to adequately describe how the injured animals were treated and managed before releasing into the wild; moreover, post-release monitoring should also be performed. Herein, we document for the first time the process of rescue, surgery, and rehabilitation of severely injured Asiatic black bears (Ursus thibetanus; endangered species in South Korea) and their fate after returning to the wild. CASE PRESENTATION: A six-year-old female (bear-01) and a three-year-old male (bear-02) bears were injured by an illegal snare and collision with a bus, respectively. Bear-01 had broad muscle necrosis and ruptures from the snared ankle on the right thoracic limb, with myiasis, and elbow disarticulation was performed. In bear-02, a non-reducible comminuted fracture of the left humerus was confirmed radiologically, and the operation was performed by using dual plate fixation with hydroxyapatite and recombinant human bone morphogenetic protein-2. The bear-01 and -02 were completely healed approximately 30 and 60 days after surgery, respectively. After that, they underwent rehabilitation for 8 and 25 days, respectively, in an outdoor enclosure similar to their natural habitat. Bear-01 and -02 were released into the wild after 45 and 99 days after surgery, respectively, and their mean daily movement distance during the first 30 days after releasing was 2.9 ± 2.1 and 1.3 ± 1.6 km, respectively. The annual mean 95% Kernel home-range size of bear-01 and bear-02 was 265.8 and 486.9 km2, respectively. They hibernated every winter, gained weight, gave birth to cubs (bear-01), were not found to have any abnormalities in the veterinary tests, and were not involved in any conflicts with humans after returning to the wild. CONCLUSIONS: Bears without one leg or those with dual plates could adapt well in their natural habitat, which shows that our surgical and post-operative treatments were effective. Additionally, minimizing human contact and observing/evaluating behavior during the rehabilitation is essential in reducing human-bear conflicts after release.

Osteogenesis of 3D-Printed PCL/TCP/bdECM Scaffold Using Adipose-Derived Stem Cells Aggregates; An Experimental Study in the Canine Mandible.

Three-dimensional (3D) printing is perceived as an innovative tool for change in tissue engineering and regenerative medicine based on research outcomes on the development of artificial organs and tissues. With advances in such technology, research is underway into 3D-printed artificial scaffolds for tissue recovery and regeneration. In this study, we fabricated artificial scaffolds by coating bone demineralized and decellularized extracellular matrix (bdECM) onto existing 3D-printed polycaprolactone/tricalcium phosphate (PCL/TCP) to enhance osteoconductivity and osteoinductivity. After injecting adipose-derived stem cells (ADSCs) in an aggregate form found to be effective in previous studies, we examined the effects of the scaffold on ossification during mandibular reconstruction in beagle dogs. Ten beagles were divided into two groups: group A (PCL/TCP/bdECM + ADSC injection; n = 5) and group B (PCL/TCP/bdECM; n = 5). The results were analyzed four and eight weeks after intervention. Computed tomography (CT) findings showed that group A had more diffuse osteoblast tissue than group B. Evidence of infection or immune rejection was not detected following histological examination. Goldner trichrome (G/T) staining revealed rich ossification in scaffold pores. ColI, Osteocalcin, and Runx2 gene expressions were determined using real-time polymerase chain reaction. Group A showed greater expression of these genes. Through Western blotting, group A showed a greater expression of genes that encode ColI, Osteocalcin, and Runx2 proteins. In conclusion, intervention group A, in which the beagles received the additional ADSC injection together with the 3D-printed PCL/TCP coated with bdECM, showed improved mandibular ossification in and around the pores of the scaffold.

Successful management of proteinuria and systemic hypertension in a dog with renal cell carcinoma with surgery, telmisartan, and amlodipine.

An 11-year-old neutered male Yorkshire terrier dog was presented with a 3-week history of hematuria and anorexia. A unilateral renal mass was detected and surgically removed. The renal mass was diagnosed on histopathologic examination as a renal carcinoma. Supportive medical therapy was carried out and persistent systemic hypertension was managed using telmisartan.

Gestion réussie de la protéinurie et de l'hypertension systémique chez un chien atteint d'un carcinome rénal à l'aide d'une chirurgie, de telmisartan et d'amlodipine. Un chien Yorkshire terrier mâle stérilisé âgé de 11 ans a été présenté avec une anamnèse de 3 semaines d'hématurie et d'anorexie. Une masse rénale unilatérale a été détectée et excisée par chirurgie. La masse rénale a été diagnostiquée à l'examen histopathologique comme étant un carcinome rénal. Une thérapie médicale de soutien a été réalisée et l'hypertension systémique persistante a été gérée à l'aide de telmisartan.(Traduit par Isabelle Vallières).

Growth-inhibition patterns and transfer-factor profiles in arsenic-stressed rice (Oryza sativa L.).

Arsenic (As) accumulation in rice owing to uptake from the soil is a critical human health issue. Here, we studied the chemical properties of As-treated soils, growth inhibition patterns of As-stressed rice plants, changes in the As content of soil and soil solutions, and the relationship between As accumulation and As transfer factor from the soil to the rice organs. Rice plants were cultivated in a greenhouse under four concentrations of As: 0 (control), 25, 50, and 75 mg kg-1. A significant positive correlation was found between available P2O5 and exchangeable K and between As concentration and available P2O5 or exchangeable K. The As concentration for 50% shoot growth inhibition was 50 mg kg-1. As levels in roots and shoots were positively correlated with the growth stages of rice. The transfer factor (TF)root/soil increased with As concentration at the tillering stage but decreased at the heading stage. TFroot/soil and TFshoot/soil were higher at the heading stage than at the tillering stage. As accumulation in the 25 mg kg-1 treatment was higher during the heading stage, whereas no difference was found at the tillering stage. As accumulation was related to plant biomass and soil As concentration. We found that As accumulation was greater at As concentrations that allowed for plant growth and development. Thus, species-specific threshold concentrations must be determined based on As phytotoxicity for the phytoremediation of As-contaminated soils. Hence, developing practical approaches for managing safe crop production in farmlands with an As contamination of 25 mg kg-1 or less is necessary.

Proteomic analysis of gingival tissue and alveolar bone during alveolar bone healing.

Bone tissue regeneration is orchestrated by the surrounding supporting tissues and involves the build-up of osteogenic cells, which orchestrate remodeling/healing through the expression of numerous mediators and signaling molecules. Periodontal regeneration models have proven useful for studying the interaction and communication between alveolar bone and supporting soft tissue. We applied a quantitative proteomic approach to analyze and compare proteins with altered expression in gingival soft tissue and alveolar bone following tooth extraction. For target identification and validation, hard and soft tissue were extracted from mini-pigs at the indicated times after tooth extraction. From triplicate experiments, 56 proteins in soft tissue and 27 proteins in alveolar bone were found to be differentially expressed before and after tooth extraction. The expression of 21 of those proteins was altered in both soft tissue and bone. Comparison of the activated networks in soft tissue and alveolar bone highlighted their distinct responsibilities in bone and tissue healing. Moreover, we found that there is crosstalk between identified proteins in soft tissue and alveolar bone with respect to cellular assembly, organization, and communication. Among these proteins, we examined in detail the expression patterns and associated networks of ATP5B and fibronectin 1. ATP5B is involved in nucleic acid metabolism, small molecule biochemistry, and neurological disease, and fibronectin 1 is involved in cellular assembly, organization, and maintenance. Collectively, our findings indicate that bone regeneration is accompanied by a profound interaction among networks regulating cellular resources, and they provide novel insight into the molecular mechanisms involved in the healing of periodontal tissue after tooth extraction.

In Vitro Evaluation of Hydroxyapatite-Coated Titanium Implant with Atmospheric Plasma Treatment.

Plasma treatments are becoming a popular method for modifying the characteristics of a range of substrate surfaces. Atmospheric pressure plasma (APP) is cost-efficient, safe and simple compared to high-pressure plasma. This study examined the effects of a low-temperature APP treatment of a hydroxyapatite (HA)-coated Ti (HA-Ti) surface. The APP treatment made the HA-Ti surfaces more hydrophilic without changing surface morphologies. The APP-treated HA-Ti (APP-HA-Ti) surface showed enhanced cell spreading, cell proliferation, and alkaline phosphatase (ALP) levels with more developed cellular networks, and the formed extracellular matrix (ECM) was fused perfectly with the HA substrate than that on the HA-Ti surface. In conclusion, an APP treatment is a potential surface-modifying method that can enhance the cell affinity at the early stages in vitro.

Analysis of Removal Torque of Injection Molded Zirconia Implants; An Experimental Study on Beagles.

This study compared the removal torque between injection molded zirconia implants and titanium implants with resorbable blast media (RBM) surfaces in beagle humeri. Fifteen screw-shaped implants were classified into 3 groups; titanium implant with RBM surface (Group RT), injection molded zirconia implant (Group Zr) and injection molded zirconia implant with sand-blasted surface (Group ZrS). Implants were inserted into beagle humeri. After 12 weeks, removal torque values were measured. The Zr group has a slightly higher removal torque value than the RT and ZrS groups but there were no significant differences among groups. Zirconia implants shows a similar removal torque to RBM titanium implants. This in vivo study showed injection molded zirconia implants could be an alternative to RBM titanium implants in terms of removal torque.

Effects of PMMA and Cross-Linked Dextran Filler for Soft Tissue Augmentation in Rats.

This study was conducted for evaluation of the ability to maintain efficacy and biocompatibility of cross-linked dextran in hydroxypropyl methylcellulose (DiHM) and cross-linked dextran mixed with PMMA in hydroxypropyl methylcellulose (PDiHM), compared with hyaluronic acid (HA) filler. Saline and HA solution was administered in the negative and positive control groups, and DiHM and PDiHM were administered in the test groups (n = 10 in each group). The site of cranial subcutaneous injection was the mid-point of the interpupillary line, and the site of intraoral submucosal injection was the ridge crest 2 mm below the cervical line of the mandibular left incisor. Before and immediately after filler injection, intraoral photos and lateral cephalometric radiographs were taken for analysis and comparison of the effect of the filler on the injection sites. The filler injected areas were converted into sequential size changes (%) of the baseline. Histomorphologic examination was performed after 12 weeks. The smallest value in the filler injected area was observed during the experimental period in the normal saline group (p < 0.001), which was almost absorbed at 4 weeks (7.19% ± 12.72%). The HA group exhibited a steady decrease in sequential size and showed a lower value than the DiHM and PDiHM groups (saline < HA < DHiM, PDHiM, p < 0.001). DiHM and PDiHM tended to increase for the first 4 weeks and later decreased until 12 weeks. In this study on DiHM and PDiHM, there was no histological abnormality in cranial skin and oral mucosa. DiHM and PDiHM filler materials with injection system provide an excellent alternative surgical method for use in oral and craniofacial fields.

Antibacterial releasing titanium surface using albumin nanoparticle carriers.

We developed a simple and highly efficient method for delivery from titanium (Ti) surfaces using albumin nanoparticle carriers. A Ti disc with a resorbable blasting media surface was used as a metal implant with a localized drug delivery structure. Human serum albumin (HSA) nanoparticles loaded with chlorhexidine (CHX) diacetate salt hydrate as the model drug were fabricated using a desolvation technique. The CHX-loaded HSA nanoparticles produced were cross linked with glutaraldehyde (GA). The nanoparticles were pre-coated with positively-charged polyethylenimine (PEI) molecules and then immobilized via electrical interactions on the negatively charged Ti disc surface. Our results suggested that the PEI-coated HSA nanoparticles loaded with CHX (PEI-CHX-HSA) were incorporated successfully and well-dispersed on the Ti disc surfaces. The agar diffusion test on the Ti surface treated with PEI-CHX-HSA nanoparticles showed a larger growth inhibition zone of Streptococcus mutans versus the control Ti surface, suggesting that this innovative delivery platform imparts potent antibacterial activity to the Ti surface. Thus, CHX, which inhibits the growth of oral bacteria, can be efficiently incorporated onto Ti surfaces by using HSA nanoparticles.

Evaluation of Non-invasive Fat Reduction Using a Resistive Electric Transfer-based Radiofrequency Device With Multi-channel Handpieces.

BACKGROUND/AIM: Various devices for non-invasive body shape correction are being developed along with the growth of the beauty industry. Radiofrequency (RF) can selectively reduce subcutaneous fat without causing skin damage. The efficacy of the procedure can be improved by applying RF to a large area simultaneously with multiple handpieces. This study evaluated the safety and efficacy of a new RF device with multi-channel handpieces. MATERIALS AND METHODS: In ex vivo experiments, the RF device was used to treat porcine tissue comprising the skin, subcutaneous, and muscle layers. The device's safety was evaluated by temperature measurements of porcine tissue and histological analysis. In in vivo experiments, the dorsal skin of pigs was treated with the RF device. The safety and efficacy of the device were evaluated by measuring the skin temperature, subcutaneous fat layer thickness, and conducting histological analysis. RESULTS: The skin temperature did not exceed the set temperature during treatment, and skin damage was not observed in histologic analysis in both ex vivo and in vivo experiments. In in vivo experiments, the subcutaneous fat layer thickness and subcutaneous lipocyte size were decreased after treatment. In addition, the fibrous tissue between subcutaneous lipocytes was increased in the RF treatment group compared with the non-treatment group. CONCLUSION: The RF device used in this study effectively reduced the size of subcutaneous lipocytes and increased fibrous tissue without skin damage. Therefore, the safe and effective use of this device for non-invasive fat reduction may be possible in clinical settings.

Outcomes of root canal treatments with three different sealers for 120 fractured maxillary fourth premolar teeth in small-to medium-sized dogs.

Introduction: Tooth fracture is one of the most common traumatic maxillofacial injuries in dogs and cats. For fractures with pulp exposure occurring in functionally important teeth, the literature indicates that root canal treatment (RCT) is an effective therapy option that may be the remedy of choice before extraction. The most commonly reported fractures in the United States involve canine teeth; however, fractures of the maxillary fourth premolars are more common in Korea, where there are many small-and medium-sized dogs. RCT mechanically and chemically removes pulp tissue and bacteria (cleaning and shaping) from the infected root canal, and obturates the root canal with filling material to restore tooth functionality without inflammation. Various techniques, instruments, and materials used in humans have been modified for application in veterinary dentistry. Methods: This study analyzed the results of RCT of the maxillary fourth premolar in 120 small-and medium-sized dogs (weighing less than 25 kg) using three different sealers (silicone-based sealer, bioceramic sealer, and calcium hydroxide-based sealer) through a simple application of the single-cone technique. Results: The overall success rate of RCT in maxillary fourth premolars was 90.83%, with 8.33% no evidence of failure (NEF) and 0.83% failure. Discussion: There were no significant differences between the three different sealers. Furthermore, preexisting periapical lesion (PAL) was reconfirmed as a factor in reducing the success rate of RCT. In addition, the working length and master apical file of each root were analyzed in our study as a novel reference for endodontic veterinarians.

Evaluation of Biocompatibility and Healing Properties of Dural Substitutes Produced by Electrospinning Technology.

BACKGROUND/AIM: Dural reconstruction is a critical process after neurosurgical procedures. Improper dural repair leads to serious side-effects, such as cerebrospinal fluid leakage or infection. This is why it is important to properly repair the dura using a dural substitute, and research into dural substitutes is ongoing. The ideal dural substitute should be non-toxic, biocompatible, and capable of maintaining adequate tension and preventing cerebrospinal fluid leakage for extended periods in vivo. This study evaluated the biocompatibility and healing properties of Safe-Seal, poly-L-lactic acid synthetic bioabsorbable dural substitute produced by electrospinning technology. MATERIALS AND METHODS: Safe-Seal, was created by electrospinning, which is a technique for nanofiberizing polymers into three-dimensional structures, and its cytotoxicity was evaluated. The animal study used 30 rats, divided into three groups assessed at two time points (4 and 12 weeks). The study groups were a negative control group with no treatment, an experimental group with Safe-Seal (TDM Co. Ltd., Gwangju, Republic of Korea) implantation, and a positive control group with a commercial product, Redura® (Medprin Biotech, Frankfurt, Germany) implantation. RESULTS: Safe-Seal exhibited no cytotoxic or adverse effects in the in vivo animal study. Histologically, Safe-Seal displayed less inflammatory cell infiltration, less adhesion to brain tissue, and connectivity with the surrounding dura mater as compared to the negative control group and without any significant differences from Redura® in all evaluation criteria. CONCLUSION: Safe-Seal presented adequate biocompatibility in vivo and contributed to the healing of the dura mater at a similar level to that of Redura® when applied to dural defects.

Application of modified porcine xenograft by collagen coating in the veterinary field: pre-clinical and clinical evaluations.

Introduction: This study aimed to identify a collagen-coating method that does not affect the physicochemical properties of bone graft material. Based on this, we developed a collagen-coated porcine xenograft and applied it to dogs to validate its effectiveness. Methods: Xenografts and collagen were derived from porcine, and the collagen coating was performed through N-ethyl-N'-(3- (dimethylamino)propyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) activation. The physicochemical characteristics of the developed bone graft material were verified through field emission scanning electron microscope (FE-SEM), brunauer emmett teller (BET), attenuated total reflectance-fourier transform infrared (ATR-FTIR), and water absorption test. Subsequently, the biocompatibility and bone healing effects were assessed using a rat calvarial defect model. Results: The physicochemical test results confirmed that collagen coating increased bone graft materials' surface roughness and fluid absorption but did not affect their porous structure. In vivo evaluations revealed that collagen coating had no adverse impact on the bone healing effect of bone graft materials. After confirming the biocompatibility and effectiveness, we applied the bone graft materials in two orthopedic cases and one dental case. Notably, successful fracture healing was observed in both orthopedic cases. In the dental case, successful bone regeneration was achieved without any loss of alveolar bone. Discussion: This study demonstrated that porcine bone graft material promotes bone healing in dogs with its hemostatic and cohesive effects resulting from the collagen coating. Bone graft materials with enhanced biocompatibility through collagen coating are expected to be widely used in veterinary clinical practice.

Activation of PRMT1 and PRMT5 mediates hypoxia- and ischemia-induced apoptosis in human lung epithelial cells and the lung of miniature pigs: the role of p38 and JNK mitogen-activated protein kinases.

Severe hypoxic and ischemic injury leads to primary graft dysfunction after lung transplantation. Arginine methylation, which is responsible for the regulation of a variety of biological functions, is mediated by protein arginine methylation transferases (PRMTs). This study examined the role of hypoxia in PRMT activation in A549 human lung epithelial cells, as well as the role of ischemia in PRMT activation in the lung of miniature pigs. In A459 cells, hypoxia increased the expression of PRMT1 and PRMT5, and overexpression of PRMT1 and PRMT5 induced apoptosis. The transfection of PRMT1 and PRMT5 small interfering RNA (siRNA) prevented hypoxia-inducible factor (HIF)-1α expression and apoptosis in A549 cells. Hypoxia-induced expression of PRMT1 and PRMT5 was blocked by p38 and JNK mitogen-activated protein kinase (MAPK) inhibitors, but not by an inhibitor of extracellular signal-regulated kinases (ERK) 1/2. In the lungs of miniature pigs, ischemia stimulated PRMT1 and PRMT5 expression and induced phosphorylation of p38 MAPK (p-p38), phosphorylation of JNK (p-JNK), and apoptotic molecules. These results demonstrate that PRMT1 and PRMT5 are involved in hypoxia and ischemia-induced apoptosis via p-p38 MAPK and p-JNK in in vitro and in vivo models.

Titanium dioxide nanotube modified implants: an animal study on bone formation.

This study examined the bone response to titanium dioxide nanotube modified implants. A total of 24 implants were placed in the femur of 4 beagles. Before placement, screw-shaped implants were classified into 3 groups; machined surface (group M), titanium dioxide nanotube modification of the machined surface (group MN) and titanium dioxide nanotube modification of the RBM surface (group RN). The texture morphology was observed via scanning electron microscopy. Animals were euthanized after 4 and 12 weeks of submerged healing and the histologic and histomorphometric analyses were performed. Groups MN and RN showed a significantly higher percentage of mineralized bone than that in group M (p < 0.05). The results of this in vivo study constitute significant evidence that the presence of the titanium dioxide nanotubes enhance osseointegration of implants.

The effect of rhBMP-2 and PRP delivery by biodegradable ß-tricalcium phosphate scaffolds on new bone formation in a non-through rabbit cranial defect model.

This study evaluated whether the combination of biodegradable ß-tricalcium phosphate (ß-TCP) scaffolds with recombinant human bone morphogenetic protein-2 (rhBMP-2) or platelet-rich plasma (PRP) could accelerate bone formation and increase bone height using a rabbit non-through cranial bone defect model. Four non-through cylindrical bone defects with a diameter of 8-mm were surgically created on the cranium of rabbits. ß-TCP scaffolds in the presence and absence of impregnated rhBMP-2 or PRP were placed into the defects. At 8 and 16 weeks after implantation, samples were dissected and fixed for analysis by microcomputed tomography and histology. Only defects with rhBMP-2 impregnated ß-TCP scaffolds showed significantly enhanced bone formation compared to non-impregnated ß-TCP scaffolds (P < 0.05). Although new bone was higher than adjacent bone at 8 weeks after implantation, vertical bone augmentation was not observed at 16 weeks after implantation, probably due to scaffold resorption occurring concurrently with new bone formation.

Successful Surgical Outcome of Feline Inductive Odontogenic Tumor in Three Cats.

BACKGROUND/AIM: A feline inductive odontogenic tumor (FIOT) is a rare type of tumor that is unique to young cats. CASE REPORT: Herein, we report on three cats (aged 6 months to 2.5 years) that had a bulging mass on the maxilla. On diagnostic imaging, cases 1 and 3 had bone expansion in the affected area, and all three cats were diagnosed with FIOT by histological examination. Maxillectomy and/or incisivectomy techniques were performed according to the tumor site with an intended surgical margin of 5 mm. To increase both precision and safety, a piezoelectric surgical instrument was used. The local advancement flaps were used to repair the surgical sites. The surgical outcomes were excellent, and there were no major complications related to the surgery or tumor recurrences during long-term follow-up (3-5 years) for any of the cats. CONCLUSION: The results from this study were excellent, which may have been due in part to the choice of the surgical instrument that allowed for the implementation of precise and accurate surgical excision and the tension-free flap method for preventing dehiscence of the surgical site.

Composite system of PLCL scaffold and heparin-based hydrogel for regeneration of partial-thickness cartilage defects.

Delivering isolated chondrocytes with matrix is a promising approach to promote the cartilage repair. The present study attempted to combine the advantages of porous scaffold and hydrogel in delivering chondrocytes to partial-thickness cartilage defects. An electrospun, gelatin-incorporated PLCL scaffold mechanically similar to natural cartilage was fabricated, and chondrocytes were seeded using an injectable heparin-based hydrogel for efficient cell seeding. The scaffold/hydrogel composite showed more enhanced expression of chondrogenic genes and production of GAGs than those prepared without hydrogel. In addition, significant cartilage formation showing good integration with surrounding, similar to natural cartilage, was observed by scaffold/hydrogel composite system in partial-thickness defects of rabbit knees while no regeneration was observed in control defects. Although no exogenous chondrogenic factors were added, it was evident that the scaffold/hydrogel composite system was highly effective and better than the scaffold alone system without hydrogel for cartilage regeneration both in vitro and in vivo.