Anti‐Swelling, Robust, and Adhesive Extracellular Matrix‐Mimicking Hydrogel Used as Intraoral Dressing

Abstract

in which it resides. In addition to poor dental hygiene, many activities, such as smoking, sucking behavior, spitting, rinsing, eating an improper diet, undergoing radiotherapy, or taking particular medications, such as bisphosphonate, have serious impacts on the healing of an extraction wound. Leaving cotton balls, gauzes, or sponge plugs on the wounds to promote blood clotting is the standard method clinically for treating extraction sockets; However, these temporary dressings cannot provide continuous protection or treatment for wound repair. Due to the lacking of available barrier dressings that prevent oral irritants from entering the socket, delayed wound healing, and other severe postoperative complications, including secondary hemorrhage, dry socket, infection, trismus, and osteonecrosis, often occur. [2] Suturing can help close the socket and control bleeding, but suturing in the confined area inside the oral cavity requires excellent operational skills and a long surgical time. [3] Therefore, it is imperative to develop an intraoral wound healing-specific dressing to provide durable and robust isolation from the wet, dynamic environment of the oral cavity.Due to its softness and high-water content, hydrogel is a popular material for wound dressings. In dentistry, hydrogels, such as chitosan-poly(γ-glutamic acid), [4] collagen, [5] poly(lactic-coglycolic acid), [6] and polyethyleneimine-poly(vinyl pyrrolidone) [7] Due to the wet and dynamic environment of the oral cavity, the healing of intraoral wounds, such as tooth extraction wounds, requires stable and firm wound dressings. In clinical practice, cotton balls and gauzes, sponge plugs, or sutures are used to treat extraction wounds, but none of these means can continuously isolate the wound from the intraoral environment and facilitate ideal healing conditions. Herein, inspired by the natural extracellular matrix, a family of wound dressings is developed for intraoral wound repair. Infiltrating a ductile long-chain hydrogel network into a prefabricated, sturdy macromolecular meshwork and in situ crosslinking endowed the composite hydrogel with controllable swelling behaviors and robust mechanical properties. The macromolecular meshwork functioned as the backbone to support the composite and restricts the swelling of the long-chain hydrogel network. In vitro tests verified that this wound dressing can provide durable protection for intraoral wounds against complex irritations. Furthermore, accelerated wound healing occurred when the wound dressing is applied in vivo on a canine tooth extraction model, due to the effective reduction of acute inflammation. These results suggest that this family of bioinspired hydrogels has great potential for application as intraoral wound dressing.

Specimen Geometry Effect on Experimental Tensile Mechanical Properties of Tough Hydrogels

“…These relatively rigid Alg networks can be combined with relatively stretchable PAM networks, becoming tough DN hydrogels. Based on the same principle and fabrication procedure as for the Alg/PAM DN hydrogel, other kinds of DN tough hydrogels that are composed of a different first-network polymer, such as agar, chitosan, cellulose, polyvinyl alcohol (PVA), i.e., Agar/PAM [ 11 , 12 ], Chitosan/PAM [ 13 , 14 , 15 , 16 ], Cellulose/PAM [ 17 ], and PVA/PAM [ 18 ] DN hydrogels, were also proposed. In addition, post-treatments to enhance the mechanical properties of the Alg/PAM DN hydrogel were usually also demonstrated [ 6 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ].…”

Recent advances in conductive hydrogels: classifications, properties, and applications

“…148–150 At present, anti-swelling hydrogels are mainly constructed by the introduction of rigid polymer meshwork to “lock” the hydrophilic groups, the protonation of zwitterionic polymer to induce the electrostatic repulsion-driven elimination of water molecules, and the introduction of nonswelling polymer and superhydrophobic modification of the hydrogel surface. 151–153 Inspired by natural extracellular matrix (ECM), Wu et al 154 reported a series of anti-swelling hydrogels, which can be applied in dynamic and wet environments, like the oral cavity. A malleable long-chain polymer network was permeated into a sturdy macromolecular framework which was prepared in advance (chitosan).…”

Low-Swelling Adhesive Hydrogel with Rapid Hemostasis and Potent Anti-Inflammatory Capability for Full-Thickness Oral Mucosal Defect Repair

“…Great efforts have been made to minimize the swelling of hydrogels, including the introduction of the double-network (DN) structure, , the use of multiple cross-linking strategies, , and the use in combination with nanocomposites . Although some low-swelling adhesive hydrogels have been reported for intraoral wound treatment, the extensive use of toxic cross-linkers and harmful polar putrefactive solvents (DMF, DMAc, and 1,4-dioxane) may negatively affect the environment as well as personnel health and adversely affect the oral mucosal wounds. , To avoid the harmful impact of hazardous chemicals on the environment and ecosystems, we have made efforts to reduce harmful reagents and chemicals at the source. Plant-derived polyphenols have attracted interest because they can act as a cross-linking agent without adding harmful substances.…”

“…10−12 Their unstable physical properties could impair their adhesion and mechanical properties, preventing them from staying in place and performing their biological functions. Great efforts have been made to minimize the swelling of hydrogels, including the introduction of the double-network (DN) structure, 13,14 the use of multiple cross-linking strategies, 15,16 and the use in combination with nanocomposites. 17 Although some low-swelling adhesive hydrogels have been reported for intraoral wound treatment, the extensive use of toxic cross-linkers and harmful polar putrefactive solvents (DMF, DMAc, and 1,4-dioxane) may negatively affect the environment as well as personnel health and adversely affect the oral mucosal wounds.…”

“…17 Although some low-swelling adhesive hydrogels have been reported for intraoral wound treatment, the extensive use of toxic cross-linkers and harmful polar putrefactive solvents (DMF, DMAc, and 1,4-dioxane) may negatively affect the environment as well as personnel health and adversely affect the oral mucosal wounds. 14,18 To avoid the harmful impact of hazardous chemicals on the environment and ecosystems, we have made efforts to reduce harmful reagents and chemicals at the source. Plant-derived polyphenols have attracted interest because they can act as a crosslinking agent without adding harmful substances.…”