Concentrated growth factor (CGF) is 100% blood-derived, cross-linked fibrin glue with platelets and growth factors. Human CGF clot is transformed into membrane by a compression device, which has been widely used clinically. However, the mechanical properties of the CGF membranes have not been well characterized. The aims of this study were to measure the tensile strength of human CGF membrane and observe its behavior as a scaffold of BMP-2 in ectopic site over the skull. The tensile test of the full length was performed at the speed of 2mm/min. The CGF membrane (5 × 5 × 2 mm³) or the CGF/BMP-2 (1.0 μg) membrane was grafted onto the skull periosteum of nude mice (5-week-old, male), and harvested at 14 days after the graft. The appearance and size of the CGF membranes were almost same for 7 days by soaking at 4 °C in saline. The average values of the tensile strength at 0 day and 7 days were 0.24 MPa and 0.26 MPa, respectively. No significant differences of both the tensile strength and the elastic modulus were found among 0, 1, 3, and 7 days. Supra-periosteal bone induction was found at 14 days in the CGF/BMP-2, while the CGF alone did not induce bone. These results demonstrated that human CGF membrane could become a short-term, sticky fibrin scaffold for BMP-2, and might be preserved as auto-membranes for wound protection after the surgery.

Total temporomandibular joint replacement (TMJR) is a surgical procedure in which end-stage temporomandibular joint disorders are replaced with an alloplastic prosthesis between the mandible and the base of the skull when autogenous grafts are inadvisable. These alloplastic prostheses may be available as stock or custom-made prostheses consisting of the mandibular condyle and glenoid fossa components. Although the first total temporomandibular joint prosthesis was used in the 1960s, we present the case of a 20-year-old female patient, probably the first case of total temporomandibular joint arthroplasty in Nepal, performed at Dhulikhel Hospital in Kavrepalanchok. The patient underwent bilateral TMJR with a custom joint prosthesis for recurrent TMJ ankylosis. Postoperatively, the patient noticed significant improvements in mouth opening, chewing ability, facial esthetics and, most importantly, her self-esteem and confidence.

Fresh compact bone, the candidate graft material for bone regeneration, is usually grafted for horizontal bone augmentation. However, the dense calcified structure inhibits the release of growth factors and limits cellular and vascular perfusion. We aimed to create mechano-chemically altered dense skull bone by ultrasonic treatment, along with partial demineralization using commercially available acidic electrolyzed water (AEW). The parietal skull bone of an 11-month-old Wistar rat was exposed and continuously treated with a piezoelectric ultrasonic scaler tip for 1 min, using AEW (pH 2.3) or distilled water (DW, pH 5.6) as irrigants. Treated parietal bone was removed, cut into plates (5 × 5 × 1 mm³), grafted into the back subcutaneous tissues of syngeneic rats, and explanted at 1, 2, and 3 weeks. AEW bone showed an irregular surface, deep nano-microcracks, and decalcified areas. SEM-EDS revealed small amounts of residual calcium content in the AEW bone (0.03%) compared to the DW bone (0.86%). In the animal assay, the AEW bone induced bone at 2 weeks. Histomorphometric analysis showed that the area of new bone in the AEW bone at 2 and 3 weeks was significantly larger. This new combination technique of AEW-demineralization with ultrasonic treatment will improve the surface area and three-dimensional (3D) architecture of dense bone and accelerate new bone synthesis.

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Introduction: Cementoenamel junction (CEJ) represents the anatomic limit between the crown and root surface and is defined as the area of the union of the cementum and enamel at the cervical region of the tooth. However, the type of CEJ in the Nepali population is not well documented. Objective: In the present study, the authours attempt to characterize the morphological type of CEJ in the Nepali population. Methods: This is a descriptive cross-sectional study using a total of 300 CEJs from the Nepali population visiting the Kathmandu University School of Medical Sciences, Department of Dental Surgery, Dhulikhel Hospital (KUSMS-DH) between January 2023 to August 2023. Extracted teeth were sectioned to 250μm thickness and observed under the light microscope to determine the type of CEJ. Results: Most of the samples presented type I CEJ. Type I, II, and III CEJ were seen in 149 (49.67%), 103 (34.33%), and 48 (16%) of the samples respectively. Additionally, 110 (73.34%) of the samples showed similar types of CEJ in both the buccal and palatal sides of the same tooth while 40 (26.66%) had different types of CEJ within the same tooth. Conclusions: Type I CEJ is the most common in the Nepalese population. The type of CEJ shows variation within the same teeth in different areas.