EFFICACY OF MORUS ALBA FRUIT EXTRACTS AND CHLORHEXIDINE ON SALIVARY STREPTOCOCCUS MUTANS AND pH LEVELS

INTRODUCTION Streptococcus mutans is the major pathogen involved in the development of dental caries. This is an anaerobic gram positive coccus, naturally present in the oral microbiota and can easily colonize on the tooth surface and initiates production of acid by combining extracellular polysaccharide that results in demineralization of tooth and development of dental caries (Shah et al., 2018). The quantity of colonized surfaces is associated with streptococcus mutans in the saliva. Thus, by decreasing the concentration of Streptococcus mutans in the mouth cavity would have a significant advantage in reducing the occurrence of cariogenic microbes. (Lemos et al., 2019, Forssten et al., 2010, Banas and Drake., 2018) Dental caries is a microbial disease of the oral cavity, which is identified by demineralization of the inorganic substances and dissolution of the organic substances of the teeth. Dental caries has been recognized throughout history and exists around the world, reported to be 44%, but the severity and prevalence changes in different countries (J.V Soames and J.C Southam et al., 2018). In our neighboring countries, the frequency of dental caries is quite high, documented to be 68%, 65% and 64% in China, Iran and India respectively. The prevalence of dental caries in Pakistan is also quite high, around 62%, which is associated with significant morbidity and economic consequences (Reddy K S, et al., 2017, Lu Liu et al., 2013) Dental caries basically involves contact between the tooth structure, the sugars and biofilm formed on the tooth surfaces (Pitts, N. B et al., 2016). The caries process composed of altering periods of demineralization and remineralization of tooth, which, if net demineralization happens over adequate time, results in the initiation of dental caries. The cause of dental caries is lactic acid produced by fermentation of sugars by oral bacteria (Banas and Drake., 2018). The normal pH level of saliva is 6.2- 7.6. At neutral pH, calcium and phosphate ions from the saliva incorporate into the enamel and maintain the structure of enamel, but when the pH level falls below normal, i.e. at 5.5 or below 5.5, the calcium and phosphate ions from the enamel leach out and causes the exchange of minerals ions from hydroxyapatite crystals of enamel into plaque, resulting in demineralization of tooth (J.V Soames Oral pathology 2018).

Dental caries management emphasizes on reducing tooth demineralization by changing eating habits, altering or inhibiting bacterial growth, changing the salivary pH level and buffering capacity (Khirtika et al., 2017, Velmurugan et al., 2013, Yang et al., 2018). Different antimicrobial synthetic mouthwashes, toothpastes, gels, chewing gums and varnishes have been used to improve mouth hygiene and prevent dental caries by aiming cariogenic microorganisms. The prevention of dental caries is done by mouth brushing after meal, by using fluoride toothpastes, antimicrobial mouthwashes, interdental cleaning aids, salivary stimulants (xylitol, mannitol), pit and fissure sealants, and application of topical fluoride on teeth surfaces. Mouth rinses also reduce gingival inflammation and inhibit plaque formation (Velmurugan et al., 2013, Chen and Wang, 2010, Zajkani et al., 2018). Mouthwashes have anticariogenic effects, but have certain disadvantages. They are costly, have side effects including staining of the teeth and burning sensation in the oral cavity (Nayak et al., 2012, Aoun et al., 2018).

Chlorhexidine is gold standard, commonly used and most effective chemical approach to decrease the accumulation of plaque. Daily rinsing mouth with chlorhexidine (0.2%) has been shown to reduce the growth rate of streptococcus mutans in the oral cavity (Velmurugan et al., 2013). However, it has certain side effects, i.e. oral mucosal erosion, parotid swelling, staining of teeth, burning feeling and bitter taste. (Jacob and Nivedhitha, 2018b, Shah et al., 2018, Van der Weijden et al., 2010, Nayak et al., 2012, Solderer et al., 2019) Many populations use medicinal plants as traditional or alternative treatments for various ailments due to their better safety profiles, health beneficial effects, lower cost and easy availability. Among the plant species used for medicinal purposes are those of the genus Morus, includes most commonly used species are Morus alba, rubra and nigra, that have also shown antimicrobial properties against various life threatening infections (Ercisli S et al., 2006). Morus alba commonly called as white mulberry, and it belongs to family Moraceae is otherwise called Tut, shahtoot or mulberry. Morus Alba (white mulberry) is native to China, India, Pakistan and Japan (Kumar V et al., 2008). In the current study, Morus alba fruit extract will be compared with chlorhexidine to Streptococcus mutans against oral pathogens due to its antimicrobial properties.

Statement of the problem Dental caries is highly prevalent across the globe including Pakistan; it causes tooth loss, malocclusion, and temporomandibular joint problems. The associated infections may carry risk of spreading into superficial and deep fascial spaces and, even may cause life threatening infections. Treatment of dental caries is quite expensive and poses an economic burden on our already deprived low socioeconomic population. So, there is need of exploration of natural products that may have antimicrobial and other beneficial effects to decrease the caries activity along with good safety profiles, easily available and cost-effective.

Research question Are the aqueous extracts of Morus alba fruit equally effective as chlorhexidine mouthwash for the prevention of dental caries? Objectives To compare the efficacy of Morus alba fruit extracts with chlorhexidine in patients having dental caries on the basis of reduction in counts of Streptococcus mutans in their saliva.