Objective: To evaluate the function of Piezo1, an evolutionarily conserved mechanically activated channel, in periodontal ligament (PDL) tissue homeostasis under compressive loading. Materials and Methods: Primary human PDL cells (hPDLCs) were isolated, cultured, and then subjected to 2.0 g/cm ² static compressive loading for 0.5, 3, 6, and 12 hours, respectively. The expressions of Piezo1 and osteoclastogenesis marker gene were assessed by semiquantitative reverse transcription–polymerase chain reaction. In addition, Piezo1 inhibitor, GsMTx4, was used to block the function of Piezo1, and tumor necrosis factor–α was also used as a positive control. After 12 hours of compressive loading the PDLCs were co-cultured with murine monocytic cell line RAW264.7. Immunofluorescence, western blot, enzyme-linked immunosorbent assay, and tartrate-resistant acid phosphatase staining were also used to test the potency of PDLCs to induce osteoclastogenesis and the activation of nuclear factor (NF)-κB. Results: Piezo1, cyclooxygenase-2, receptor activator of NF-κB ligand, and prostaglandin E2 were significantly upregulated under static compressive stimuli. GsMTx4 repressed osteoclastogenesis in the mechanical stress–pretreated PDLCs-RAW264.7 co-culture system. Furthermore, NF-κB signaling pathway was involved in the mechanical stress–induced osteoclastogenesis. Conclusions: Piezo1 exerts a transduction role in mechanical stress–induced osteoclastogenesis in hPDLCs.

Opaqueness of animal tissue can be attributed mostly to light absorption and light scattering. In most noncleared tissue samples, confocal images can be acquired at no more than a 100-µm depth. Tissue-clearing techniques have emerged in recent years in the neuroscience field. Many tissue-clearing methods have been developed, and they all follow similar working principles. During the tissue-clearing process, chemical or physical treatments are applied to remove components blocking or scattering the light. Finally, samples are immersed in a designated clearing medium to achieve a uniform refractive index and to gain transparency. Once the transparency is reached, images can be acquired even at several millimeters of depth with high resolution. Tissue clearing has become an essential tool for neuroscientists to investigate the neural connectome or to analyze spatial information of various types of brain cells. Other than neural science research, tissue-clearing techniques also have applications for bone research. Several methods have been developed for clearing bones. Clearing treatment enables 3-dimensional imaging of bones without sectioning and provides important new insights that are difficult or impossible to acquire with conventional approaches. Application of tissue-clearing technique on dental research remains limited. This review will provide an overview of the recent literature related to the methods and application of various tissue-clearing methods. The following aspects will be covered: general principles for the tissue-clearing technique, current available methods for clearing bones and teeth, general principles of 3-dimensional imaging acquisition and data processing, applications of tissue clearing on studying biological processes within bones and teeth, and future directions for 3-dimensional imaging.

The cranial bones constitute the protective structures of the skull, which surround and protect the brain. Due to the limited repair capacity, the reconstruction and regeneration of skull defects are considered as an unmet clinical need and challenge. Previously, it has been proposed that the periosteum and dura mater provide reparative progenitors for cranial bones homeostasis and injury repair. In addition, it has also been speculated that the cranial mesenchymal stem cells reside in the perivascular niche of the diploe, namely, the soft spongy cancellous bone between the interior and exterior layers of cortical bone of the skull, which resembles the skeletal stem cells’ distribution pattern of the long bone within the bone marrow. Not until recent years have several studies unraveled and validated that the major mesenchymal stem cell population of the cranial region is primarily located within the suture mesenchyme of the skull, and hence, they are termed suture mesenchymal stem cells (SuSCs). Here, we summarized the characteristics of SuSCs, this newly discovered stem cell population of cranial bones, including the temporospatial distribution pattern, self-renewal, and multipotent properties, contribution to injury repair, as well as the signaling pathways and molecular mechanisms associated with the regulation of SuSCs.

Effective therapeutic intervention for central nervous system (CNS) diseases, including brain tumors and neurodegenerative disorders, is significantly challenged by the formidable blood-brain barrier (BBB). This biological barrier severely restricts the passage of most drug candidates, resulting in inefficient delivery to pathological sites and substantially contributing to high clinical trial failure rates for CNS therapies. Engineered nanoparticles have emerged as promising functional material systems capable of navigating these delivery obstacles, offering advantages like encapsulating diverse agents, controlled release, and targeted delivery. This review comprehensively analyzes innovative nanoparticle strategies specifically designed to overcome the BBB and achieve precise CNS delivery via systemic administration. We highlight the critical multi-step biological cascade required for successful therapeutic outcomes: maintaining colloidal stability in circulation, efficiently penetrating the BBB, achieving specific accumulation at the disease site, and effectively engaging target cells. Despite significant advancements, clinical translation of these nanoparticle systems remains limited. A thorough understanding of this multi-step process is paramount to accelerating the clinical application of brain-targeted nanomedicines.

A unilateral scissor bite is a type of severe malocclusion in primary dentition that can influence the development of the mandible and face. The present case report describes an interceptive treatment on a 4-year-old girl with a unilateral scissor bite combined with an anterior crossbite, increased reverse overjet, and overbite on a skeletal Class III base. The patient was treated with a new Prefabricated Functional Appliance (PFA) which was modified from a Frankel-III appliance to induce a mandible to move backwards and relieve an occlusion discrepancy of the dental arch, and a functional dental rehabilitation with resin and myofunctional exercises with a PFA which was modified from an oral screen appliance were performed during the treatment. The total treatment time was 11 months and a satisfactory improvement of occlusion and facial esthetics was achieved. This case report presents a new PFA system and treatment protocol in primary dentition which results in a favorable outcome, and the clinical effectiveness of this appliance system warrants further investigation.