Dental caries and periodontal diseases are the two most prevalent human diseases that are related to and progressed by dental plaque formation and collection on the enamel surface. The removal or inhibition of dental plaque establishment by herbal or natural materials with antibacterial, anti-inflammatory, and antioxidant properties prevents plaque accumulation on the enamel surface, caries, and gingival and periodontal diseases (Faraj et al., 2007) (Ghasemi et al., 2017).

Almost all people have dental caries during their life. Caries prevention strategies include fluoride therapy, fissure sealant therapy, low sugar in the diet, and regular dental visits. Caries prevention by other popular ways is essential in the early-stage to stop caries progression (Deshpande and Jadad, 2008). Modern dentistry aims to prevent caries initiation and enamel remineralization in early stages before cavitation to improve prognosis (Cochrane et al., 2010).

Salivary molecular and enzymatic antioxidants play an essential role in oral health and caries prevention. Individuals with dental caries showed reduced antioxidants than the caries-free group (Ahmadi-Motamayel et al., 2013a, Ahmadi-Motamayel et al., 2018, Hegde et al., 2013, Mahjoub et al., 2014). Vitamin E (α-tocopherol) is a molecular antioxidant with oral health properties (Torshabi et al., 2017).

Sugar-free chewing gums have many beneficial effects on oral health. Chewing gums containing efficacious active herbal and pharmaceutical agents (fluoride and chlorhexidine) with medical properties also increase chewing gum beneficial effects with drug delivery and extended exposure to the teeth and oral cavity. Chewing gums remove biofilms, neutralize plaque acids, increase the salivary flow rate, have a buffering capacity, remineralize enamel, reduce the risk of caries, prevent incipient and initial caries, and have anti-gingivitis properties. Chewing gums can be used as food, cosmetics, drugs, and medical devices that deliver medicines and other therapeutic factors (Dodds et al., 2012) (Hegde et al., 2017).

In vitro and in vivo studies have shown that chewing gums after meals decrease dental caries development, plaque acidity, and demineralization and increase remineralization (Szöke and Bánóczy, 2005) (Beiswanger et al., 1998). Chewing gums also reduce salivary Streptococcus mutans counts (Haghgoo et al., 2015).

Herbal products with medicinal properties can be used in dental and food products such as toothpaste, mouthwashes, chewing gums, and dental materials (Mathai et al., 2017).

Honey is an important, natural, nutritious food with antibacterial, anti-inflammatory, and antioxidants properties. (Pasias et al., 2018, Schmidlin et al., 2014). Honey has an inhibitory effect on Streptococcus mutans, and honey mouthwashes decrease salivary Streptococcus mutants counts (Ahmadi-Motamayel et al., 2013b) (Abdelmegid et al., 2015). Glycyrrhiza glabra (licorice) has immunoregulatory, anti-inflammatory, antiviral, antifungal, and antibacterial properties on oral and periodontal pathogens; it even has cariostatic potential (Sharma et al., 2016a, Sharma et al., 2016b, Yang et al., 2015) (Jain et al., 2013, Peters et al., 2010).

Considering the beneficial effects of chewing gums, Glycyrrhiza glabra, honey, and antioxidant on dental and gingival health, and also caries prevention strategies worldwide, this study aimed to formulate and evaluate the effect of chewing gum containing Glycyrrhiza glabra, honey, and Vitamin E as an antioxidants on oral and gingival health.