Bacterial biofilm colonization and persistent chronic inflammation in periodontitis cause periodontal tissue destruction and eventual tooth loss. Bacterial biofilms disruption and immune cell metabolism reprogramming are critical for the treatment of periodontitis. Herein, we developed an injectable MXene-based hydrogel (GQM), composed of oxidized gellan gum, quaternized chitosan, and magnesium–tannic acid-modified MXene nanosheets (MTA-Mg), which serves as a flexible scaffold for targeted delivery of MTA-Mg within periodontal pockets. The GQM hydrogels can be injected into periodontal pockets and targetedly deliver MTA-Mg, which disrupts the dense biofilm efficiently by photothermal effect, while the bacteria are killed through the electrostatic interaction and charge neutralization from quaternized chitosan. MTA-Mg nanosheets serve as interfacial electron transfer to activate oxidative phosphorylation pathway, while delivering the magnesium and tannic acid to improve mitochondrial function, which reprogram the immune cell metabolism by inducing macrophage toward the M2 phenotype. The rat periodontitis model demonstrated that the GQM hydrogel effectively eradicates bacterial biofilms, alleviates inflammation, and reverses alveolar bone resorption, thereby treating periodontitis efficiently. All in all, the GQM hydrogel achieves a synergistic effect of "biofilm disruption–immune metabolic reprogramming" and offers a novel strategy for the reversal of inflammatory bone resorption in periodontitis.

Chronic wound healing remains a significant clinical challenge due to persistent inflammation, oxidative stress, mitochondrial dysfunction, and cellular senescence. A near-infrared (NIR)-responsive polydopamine-resveratrol (PDA@RES) core-shell nanoplatform was developed to address these interconnected pathological mechanisms through synergistic photothermal therapy and drug delivery. The nanoplatform exhibited excellent photothermal conversion capability and demonstrated superior antioxidant and anti-inflammatory effects, effectively scavenging intracellular reactive oxygen species (ROS), restoring mitochondrial membrane potential, and repolarizing macrophages toward a pro-healing phenotype. Mechanistically, the platform activated the AMPK/PGC-1α signaling axis, initiating programmed mitochondrial homeostasis remodeling through enhanced mitophagy and biogenesis, thereby blocking senescence-inducing signals and reversing cellular senescence. The immune microenvironment remodeling subsequently promoted vascular endothelial cell migration and angiogenesis. In diabetic rat models, the NIR-responsive nanoplatform significantly accelerated wound healing by promoting collagen deposition, balancing the immune microenvironment, and facilitating functional vascular regeneration. Notably, the treatment induced nascent hair follicle structures, achieving high-quality regenerative healing rather than scar formation. This study provides an efficient, multi-target synergistic therapeutic strategy for chronic wound healing.

Sufficient bone tissue is required to ensure the long-term stability of implants. Based on the principles of guided bone regeneration, Dr. Istvan Urban proposed the "sausage technique". Research indicates that the horizontal bone augmentation observed with the sausage technique averages (5.3 ± 2.3) mm and the vertical bone augmentation averages (4.2 ± 1.9) mm, which is significantly greater than the outcomes achieved with traditional guided bone regeneration techniques. The sausage technique is reliable because the biological membrane has sufficient elasticity and toughness with the application of membrane screws, which stabilizes the mixture of autologous bone and bone graft materials in the bone grafting area and prevents the grafting materials from being displaced. Using substitute materials for autologous bone graft balances the osteogenic activity and the low graft absorption rate. A ball drill is used to prepare nourishing holes in the cortical bone of the recipient area, providing a pathway for mesenchymal stem cells and bone progenitor cells to migrate to the bone regeneration area. Furthermore, this method accelerates the early angiogenesis of wound healing, fully reduces tension during suturing, and ensures that excessive pressure is not applied to the healing area during suturing. Thus, the sausage technique is consistent and reliable. Despite the good outcomes demonstrated by the sausage technique in clinical applications, its potential complications related to soft and hard tissue have attracted widespread attention. These complications negatively affect the patient's recovery process and influence the final results of the surgery. Therefore, a complete understanding of the complications associated with the sausage technique and their underlying causes is necessary to enhance the clinical safety and effectiveness of the sausage technique. This article summarizes the application principles, clinical effects, barrier membrane applications, selection of bone transplant materials, and related complications of the sausage technique, aiming to provide a reference for clinical application.