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Given the large amount of anthropogenic CO2 emissions, it is advantageous to use CO2 as feedstock for the fabrication of everyday products, such as fuels and materials. An attractive way to use CO2 in the synthesis of polymers is by the formation of five-membered cyclic organic carbonate monomers (5CCs). The sustainability of this synthetic approach is increased by using scaffolds prepared from renewable resources. Indeed, recent years have seen the rise of various types of carbonate syntheses and applications. 5CC monomers are often polymerized with diamines to yield polyhydroxyurethanes (PHU). Foams are developed from this type of polymers; moreover, the additional hydroxyl groups in PHU, absent in classical polyurethanes, lead to coatings with excellent adhesive properties. Furthermore, carbonate groups in polymers offer the possibility of post-functionalization, such as curing reactions under mild conditions. Finally, the polarity of carbonate groups is remarkably high, so polymers with carbonates side-chains can be used as polymer electrolytes in batteries or as conductive membranes. The target of this Review is to highlight the multiple opportunities offered by polymers prepared from and/or containing 5CCs. Firstly, the preparation of several classes of 5CCs is discussed with special focus on the sustainability of the synthetic routes. Thereafter, specific classes of polymers are discussed for which the use and/or presence of carbonate moieties is crucial to impart the targeted properties (foams, adhesives, polymers for energy applications, and other functional materials).

Introduction: Fibroma is a benign tumor that is composed of fibrous connective tissue (CT) and is also known as irritation or traumatic fibroma. It represents a reactive hyperplasia of fibrous CT in response to local irritation or trauma. The aim of the present case report is to evaluate the treatment outcome of two cases of fibroma of the tongue after excision with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser.Case Presentation: Two patients presented with the chief complaint of growth on the dorsal surface of the tongue, which was causing constant irritation as well as esthetic concerns. After examination, the growths were excised with an Er,Cr:YSGG laser in non-contact mode at a power setting of 1.5 W, 20 Hz frequency and with a spray of 9% water and 13% air. This resulted in less blood in the operating field and minimal patient discomfort. No sutures were used; instead, a laser bandage was applied. The healing was uneventful and patients did not require postoperative analgesic...