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.

Background: Root dentin transparency, one of the age changes in dentin, is considered to be a stable parameter not affected by environmental and pathological factors. The effect of age changes in the transparency of root dentin in Nepalese population have not been established so far. In the present study, we aimed to determine the age of an individual using the root dentin transparency in the Nepalese subjects and attempt to derive the formula to estimate the age applicable to the Nepalese population. Materials and Methods: A cross sectional analytical study was conducted to measure the length of root dentin transparency in the tooth of patients of known age. Correlation of the age and the length of transparent root dentin was determined. A linear regression analysis was carried out to derive a formula applicable to the Nepalese population. Results: The length of transparent root dentin increased linearly with the age of an individual. The newly derived formula was used to calculate the estimated age from the length of transparent root dentin. The difference between the actual age and the calculated age was within 6 years in 63.2% of the sample. Conclusion: A simple and relatively inexpensive method for calculating age by measuring RDT is described.

Introduction: Keratoacanthoma is an epithelial keratinocytic benign tumor. A cutaneous horn is a conical projection of hyperkeratotic epidermis. Keratoacanthoma presenting as a cutaneous horn is rare. Histopathological examination is essential to rule out malignancies, such as squamous cell carcinoma (SCC). Case presentation: A 70-year-old female patient presented with a progressively enlarging horn-like lesion on the left cheek. The lesion had rapidly increased in size over the preceding 3 months. Although the lesion was painless, the patient sought evaluation for the progressive enlargement, risk of malignant transformation, and the need for definitive diagnosis and treatment. Given the clinical suspicion of keratoacanthoma with the possibility of an underlying malignancy such as SCC, complete surgical excision was performed. Histopathological examination confirmed keratoacanthoma. The patient demonstrated satisfactory wound healing without recurrence during the 6-month follow-up period. Clinical discussion: The presented case is rare and closely resembles malignant cutaneous lesions. This case emphasizes the importance of correlating clinical findings with histopathology to establish an accurate diagnosis and guide the surgical approach. Conclusion: Keratoacanthoma associated with a cutaneous horn is an uncommon clinical entity that closely mimics SCC. First, all cutaneous horns should undergo histopathological examination because the underlying lesion cannot be reliably determined clinically. Second, complete surgical excision offers both therapeutic and diagnostic value. Third, early recognition and timely intervention may prevent delayed diagnosis of potentially malignant lesions and improve patient outcomes.