Phytodentistry: use of medicinal plants.

J Complement Integr Med. 2014; 11(4): 233–251

Review Kavita Hotwani*, Sudhindra Baliga and Krishna Sharma

Phytodentistry: use of medicinal plants Abstract: Finding healing powers in plants is an ancient idea. Herbs have been used as a traditional form of medicine since time immemorial. The natural products derived from medicinal plants have proven to be an abundant source of biologically active compounds, many of which have been the basis for the development of new chemicals for pharmaceuticals. Phytodentistry implies the use of plants and their products in the process of treating disease directly or indirectly. A crucial role is played by phytotherapy in the treatment of stomatological problems. It started with the use of miswak (chewing stick), and it is still relevant today as herbal toothpaste in many parts of the country. India is the largest producer of medicinal herbs and is appropriately called the botanical garden of the world. The use of this readily available, natural and safe resource as a part of dental practice has great potential for a more “Natural and Green Dental Practice”. Plant products have long been used in dentistry as part of various dental materials right from impression materials to eugenol, which forms an integral part of the dental clinic. The use of herbs in dental practice is not limited to only material sciences. A single herb shows a variety of effects like anti-inflammatory, antibacterial, antifungal activity and many more. Hence the incorporation of these herbs in dental practice will prove to be a valuable adjunct in dental treatment. This review is aimed at exploring the perspectives of this holistic treatment approach in dentistry and its benefits as an adjunctive therapy. Keywords: dental health, holistic, phytodentistry DOI 10.1515/jcim-2013-0015 Received May 2, 2013; accepted July 3, 2014; previously published online August 20, 2014

*Corresponding author: Kavita Hotwani, Department of Pedodontics and Preventive Dentistry, Sharad Pawar Dental College, Sawangi, Wardha, Maharashtra, India, E-mail: [email protected] Sudhindra Baliga, Department of Pedodontics and Preventive Dentistry, Sharad Pawar Dental College, Sawangi, Wardha, Maharashtra, India Krishna Sharma, Department of Orthodontics and Dentofacial Orthopaedics, Sharad Pawar Dental College, Sawangi, Wardha, Maharashtra, India

Introduction Oral diseases continue to be a key health problem globally. Dental caries and periodontal diseases are among the most important oral health problems, although conditions such as oral and pharyngeal cancers and oral tissue lesions are also substantial health concerns. The World Health Organization asserts that oral health is a basic human right, yet this is a right enjoyed by few [1]. Despite general advances in the overall health status of the people living in industrialized countries, including oral and dental health, the prevalence of dental caries in school aged children is up to 90% and majority of adults are also affected [2]. Consequently, the global need for alternative prevention and treatment options and products for oral diseases that are safe, effective and economical comes from the rise in disease incidence and increased resistance by pathogenic bacteria to currently used antibiotics and chemotherapeutics. Although several agents being commercially available, these chemicals can alter oral microbiota and have undesirable side effects such as vomiting, diarrhea and tooth staining. For example, bacterial resistance to most of the antibiotics commonly used to treat oral infections (penicillins and cephalosporins, erythromycin, tetracycline and derivatives and metronidazole) has been documented. Other antibacterial agents used in the prevention and treatment of oral diseases, including cetylpyridinium chloride, chlorhexidine, amine fluorides or products containing such agents, are reported to exhibit toxicity and cause staining of teeth, or in the case of ethanol which is commonly found in mouthwashes, it has been linked to oral cancer [3]. The natural phytochemicals could offer an effective alternative to antibiotics and represent a promising approach in prevention and therapeutic strategies for dental caries and other oral infections.

Historical review and Indian system Nature always stands out as an excellent representation to epitomize the outstanding marvel of symbiosis. Throughout the history of mankind, many infectious

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Hotwani et al.: Phytodentistry: use of medicinal plants

diseases have been treated with herbals. Finding healing powers in plants is an ancient idea. Medicinal plants play a vital role for the development of new drugs [4–6]. Hippocrates, in the late fifth century BC, cited 300– 400 medicinal plants [7]. In the first century AD, Dioscorides wrote De MateriaMedica, a medicinal plant catalog that became the prototype for modern pharmacopoeias. The Bible offers descriptions of ~30 healing plants [8]. It is also a fact that one quarter of all medical prescriptions today are formulations based on substances derived from plants or plant-derived synthetic analogs, and according to the WHO, 80% of the world’s population, primarily those of developing countries, rely on plant-derived medicines for their health care [9]. Plantderived drugs came into use in the modern medicine through the uses of plant material as indigenous cure in folklore or traditional systems of medicine. The world is now moving toward the herbal medicine or phytomedicines. Indian subcontinent is a massive repository of medicinal plants that are used in traditional medical healings, which also form a rich source of knowledge. The various indigenous systems such as Siddha, Ayurveda, Unani and Allopathy use several plant species to treat different ailments. In India around 20,000 medicinal plant species have been recorded, but more than 500 traditional communities use about 800 plant species for curing different diseases [4, 10, 11]. In this regard, India has a unique position in the world, where a number of recognized indigenous system of medicine viz., Ayurveda, Siddha, Unani, Homeopathy, Yoga and Naturopathy are being utilized for the health care of people. India is the largest producer of medicinal herbs and is called as botanical garden of the world [12, 13]. According to Gurib-Fakim [9], there are four basic ways in which plants that are used by tribal peoples are valuable for modern medicine – Plants used as sources of direct therapeutic agents – Plants are also used as sources of starting points for the elaboration of semi-synthetic compounds – Plants can serve as sources of substances that can be used as models for new synthetic compounds. – Plants can also be used as taxanomic markers for the discovery of new compounds. Ayurveda is the ancient Indian system of health care and longevity. It involves a holistic view of man, his health and illness. Ayurvedic treatment is aimed at the patient as an organic whole, and treatment consists of salubrious use of drugs, diets and certain practices [14]. There are ~1,250 Indian medicinal plants that are used in

formulating beneficial measures according to Ayurvedic or other ethnicity [15]. The botanicals in the Ayurvedic materia medica have been proven to be safe and effective, through several hundred to several thousand years of use. The exploration of botanicals used in traditional medicine, particularly traditional Asian medicine, may lead to development of novel preventive or therapeutic strategies for oral health [16].

Overview of phytodentistry Phytotherapy is the study of the use of extracts from natural origin as medicines or health-promoting agents. Traditional phytotherapy is often used as synonym for herbalism and regarded as alternative medicine [17]. The term “Phytodentistry” implies the application of phytotherapy in dentistry. For descriptive purpose, each of these herbal remedies can be grouped according to the dental application. This provides a broad classification aimed to utilize phytocompounds for dental therapeutic purposes (Figure 1). This article is a brief review of

Irrigants

Intracanal medicaments Endodontics Pulp-capping agents Dental traumatology

Retreatment agents

Dental caries prevention Zinc oxide eugenol cement

Citric acid

Herb based dental materials

Impression materials

CMCP

Oral mucosal lesions

Gutta-percha

Thymol

Surgical uses

Hemostatic agents

Wound healing

Periodontal uses

Mouthwashes, dentrifrices

Adjunct therapy

Figure 1 Classification of phytotherapeutics according to dental applications.



phytomedicinals that have potential application in prevention and treatment of dental diseases and that incorporate a holistic approach toward oral health care. The plants discussed are commonly available, safe and found to be effective against a variety of microbial diseases, including dental caries (Tables 1–8). The next part of the article will give a detail synopsis regarding scientific literature review and dental applications of these plants.

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lignins. Examples of phenolic classes of pharmaceutical interests are: – Capsaicin, isolated from Capsicum sp., is a vanillyl amide of isodecenoic acid and is marketed as an analgesic. – Eugenol is widely used in dentistry due to its antibacterial and anti-inflammatory activities.

Polyphenols

Phytochemical aspect of plants useful in dentistry The chemical compounds available in plants are called phytochemicals. Phytochemistry deals with the chemistry of plant metabolites and their derivatives [8]. The metabolic system of a plant may be regarded as being constituted of regulated processes within which biochemical conversions and mass transfer take place. The metabolic performance can be distinguished into primary metabolism and secondary metabolism. Most of the plant compounds that have been found to be medicinally useful and interesting tend to be secondary metabolites. Phytochemicals that possess many ecological and physiological roles are widely distributed as plant constituents. Some of the metabolites synthesized by the plants that have shown potentially useful medicinal and dental properties are described as follows [18]. The corresponding plants used for dental applications are described in Tables 1–8.

Alkaloids The term alkaloid has been defined as a cyclic organic compound containing nitrogen in a negative oxidation state, which has limited distribution in living organisms. Alkaloids are pharmaceutically significant as, – morphine as a narcotic analgesic – Codeine in the treatment of cough – Colchicine in the treatment of gout – quinine as an anti-malarial – quinidine as an anti-arrhythmic

Phenols and phenolic glycosides Phenols are among the largest group of secondary metabolites. They range from simple structures with one aromatic ring to complex polymers such as tannins and

Polyphenols constitute one of the most common and widespread groups of substances in plants. These are substances that contain at least one aromatic ring with one or more hydroxyl groups in addition to other substituents. Recognition of the antioxidant activities of many polyphenols has realigned thinking toward the health benefits provided by many of these compounds. Polyphenols can be mainly divided into tannins, lignins and flavonoids. (a) Tannins are astringent, bitter plant polyphenols that either bind and precipitate or shrink proteins. The anti-inflammatory effect of tannins helps control all indications of inflammation. The ability of tannins to form a protective layer over the exposed tissue keeps wounds from being infected further. Many human physiological activities, such as stimulation of phagocytic cells, host-mediated tumor activity and a wide range of anti-infective actions, have been assigned to tannins. The mode of antimicrobial action may be related to their ability to inactivate microbial adhesins, enzymes, cell envelope transport proteins and so on. (b) Flavonoids are water-soluble polyphenol molecules containing 15 carbon atoms. They have antioxidant activity. Activities attributed to flavonoids include: anti-allergic, anticancer, antioxidant, anti-inflammatory and antiviral. They show anti-allergic, antiinflammatory, antimicrobial and anticancer activity. Flavonoid compounds exhibit inhibitory effects against multiple viruses. (c) Carotenoids are organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some types of fungus and some bacteria. Most carotenoids have antioxidant activity and they are efficient free-radical scavengers. The use of natural antimicrobials may contribute to control the disordered growth of oral microbiota, thus overcoming problems caused by species resistant to conventional antimicrobials.


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(d) Catechins have been extensively researched due to their occurrence in oolong green teas. It was noticed some time ago that teas exerted antimicrobial activity and that they contain a mixture of catechin compounds. These compounds inhibited in vitro Vibrio cholerae, Streptococcus mutans, Shigella and other bacteria and microorganisms. The catechins inactivate cholera toxin in Vibrio and inhibit isolated bacterial glucosyltransferases in S. mutans, possibly due to complexing activities.

Terpenoids and essential oils The fragrance of plants is carried in the so-called quintaessentia or essential oil fraction. These oils are secondary metabolites that are highly enriched in compounds based on an isoprene structure called terpenes. When the compounds contain additional elements, usually oxygen, they are termed terpenoids. Terpenenes or terpenoids are active against bacteria, fungi and viruses.

Molecular basis of phytodentistry The use of plant biotechnology for dental applications has been in research for long. However, the exact molecular mechanisms are still unclear. This may be due to the fact that a single plant is a storehouse of many different molecules that exert various biological actions. The most common amongst these are the antioxidant, anticancer, antimicrobial and anti-inflammatory effects. These have been applied to dentistry to prevent as well as treat dental diseases. Emerging findings suggest a variety of potential mechanisms of action by which plant metabolites may prevent disease, such as the inhibition of bacterial replication enzymes, the induction of apoptosis in tumor cells, the stimulation of monocytes/macrophages to produce cytokines and the stimulation of myeloperoxidase-dependent iodination of neutrophils. However, the exact mechanism for application of these phytoconstituents in dentistry still needs research.

Perspectives of phytomedicine use in dentistry In the field of dentistry, with the paradigm shift in the understanding and management of dental diseases,

especially dental caries, based on the medical model rather than the surgical one, phytotherapy shows potential beneficial effects. The elimination of cariogenic oral microflora plays a very important role in dental caries prevention. This antimicrobial strategy can be augmented by using naturally occurring phytocompounds. As dental professionals, we all have been using these naturally occurring plants in our routine practice in the form of dental impression materials, eugenol, gutta-percha and so on. However, there is still a need to introspect the wide arena of applications of phytocompounds in dentistry with a holistic approach. Natural products remain a largely unexplored source of effective antibiofilm molecules of potentially low toxicity that could be used in alternative or adjunctive anticaries therapies in dental practice. The emergence of powerful new analytical technologies and advances in biosynthetic chemistry has opened the door to a new era in the development of novel antiplaque/anticaries therapies using naturally occurring agents. More importantly, advances in plant genomics, metabolic engineering and biosynthetic chemistry can now provide reproducible and optimized sources for the isolation and/or production of bioactive agents. Although natural products from traditional medicine or plant-derived foods are generally not expected to have acute toxicological effects, comprehensive safety studies, especially following brief-exposure topical application of these agents, need to be evaluated prior to clinical trials. In addition, innovative delivery systems and improved solubilization methods would greatly enhance the applicability of natural products as anticaries agents [19]. In modern dental practice, we are living in an age of evidence-based dentistry. Any material with potential clinical application must go through a series of tests to demonstrate biocompatibility to the tissues of the oral cavity as well as marked advantages in terms of efficacy in clinical applications when compared to contemporary methods. In vivo studies will also be required for recommending ideal clinical protocols using these materials. Currently, the development and accessibility of information on phytopharmaceuticals and natural medications are gradually gaining the respect of some patients and health professionals. Besides, the exploitation of these substances has a socioeconomic impact. It will lead to an increase in cultivation fields and in the market of informal herbs, as well as in an expansion of small and medium national pharmaceutical laboratories dedicated to manufacturing medicaments of natural and vegetable origin. The identification of phytocompounds having potential uses in dental practice will change dentistry to green



dentistry. Finally, natural agents can be used alone as single molecules, and/or in combination with other agents for enhanced therapeutic effects. The use of natural agents to enhance the cariostatic properties of fluoride could be a promising and potent novel anticaries strategy. Clearly, there is great potential for the discovery of therapeutically relevant compounds from nature. However, careful experimental designs using multidisciplinary approaches in conjunction with the standardization and characterization of natural products are critical for the successful development of novel and useful anticaries chemotherapy. The implementation of standardized and stepwise cross-disciplinary approaches would help to advance this field of investigation in phytodentistry. Thus, in light of the increasing scientific knowledge about the beneficial properties of plant derivatives, this holistic therapy can be applied to the field of dentistry to attain preventive as well as therapeutic benefit for oral diseases. Plants have forever been a catalyst for our healing. Evaluating plants from the traditional Indian system of medicine provides us with clues as to how these plants can be used in the treatment of disease. Many of the plants presented here show very promising activity in controlling oral diseases, warranting further investigation.

Review of dental applications Endodontics The use of phytomedicine for endodontic purposes has gained considerable importance due to a variety of actions in a single herb. Herbs have been used as an antimicrobial agent against various endodontic pathogens. Herbs have also been long used in various endodontic medicaments and dressings with obtundent and soothening effects.

Endodontic irrigants They are commonly used for root canal debridement as part of chemo-mechanical preparation. Local wound debridement in the diseased pulp space is the main step in root canal treatment to prevent the tooth from being a source of infection. Sodium hypochlorite solutions are recommended as the main irrigants. This is because of their broad antimicrobial spectrum as well as their unique capacity to dissolve necrotic tissue remnants. In addition, chelating solutions are recommended as adjunct irrigants

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to prevent the formation of a smear layer and/or remove it before filling the root canal system [20]. However, in the dental literature several mishaps during root canal irrigation have been described, ranging from damage to the patient’s clothing, splashing the irrigant into the patient’s or operator’s eye, to injection through the apical foramen, or air emphysema and allergic reactions to the irrigant. The accidents during endodontic therapy may occur when the root canal is dried with compressed air, which may be expressed through the apical constriction into the periapical tissues. Shovelton [21] presented 13 cases that had signs of emphysema of the face, the suborbital region and neck. Also, sodium hypochlorite can lead to severe tissue reactions characterized by pain, swelling, hemorrhage and potentially secondary infection or lasting paresthesia when injected beyond the dermis and into soft tissue. If the area becomes secondarily infected by pathogenic flora, there is a risk for sepsis and endocarditis. These chemical and toxicological concerns related to their use have renewed the interest in search of newer alternatives [22]. The medicinal plants investigated as potential endodontic irrigants are chamomile, white tea tree, mustard tree, neem tree, Indian mulberry tree and green tea extracts (GTEs). In addition, propolis, which is a resinous mixture that honeybees collect from tree buds, sap flows or other botanical sources, has also been investigated for endodontic purposes (Table 1). Matricaria recutita and the tea tree oil have been considered effective agents in removing root canal smear layer. Both showed better properties than 2.5% sodium hypochlorite (NaOCl) and distilled water [23]. When a comparison of cleaning effectiveness of chamomile hydroalcoholic extract and tea tree oil to 2.5% NaOCl solution as an intracanal irrigant for the removal of the smear layer was made, chamomile extract was found to be significantly more effective than distilled water and tea tree oil [24]. Also, a high antimicrobial activity of Salvadora persica extract against aerobic and anaerobic microorganisms was demonstrated at 15% concentration [25]. Such antimicrobial effect of alcoholic extract of S. persica is believed to be due to its high chemical contents of chlorides, tannins, trimethylamine, salvadorine, nitrate, thiocynate and sulfur [23]. Azadirachta indica is a common medicinal tree in India, which is considered holy. It is known since 2000 years as one of the most versatile medicinal plants having a wide spectrum of biological activity. In Sanskrit, it is called “arishtha” meaning reliever of sickness and is regarded as the village dispensary of India [26]. In an in vitro study comparing the antibacterial efficiency of


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Table 1


Endodontic irrigants. Active phytochemical constituent

Action

Native of Europe, grown in Jammu and Kashmir, Himachal Pradesh

Terpenoids, flavonoids

Sedative, anticonvulsant, antispasmodic, analgesic, antiinflammatory, antiseptic

White tea tree (cajeput Melaleuca leucadendron tree/swamp tea tree)

Indigenous to Burma, Thailand, Australia; grown in Indian gardens and parks

Essential oil, terpenes

Antimicrobial

Mustard tree Salvadora persica (miswaak/tooth brush tree)

Arid regions, on saline lands and in coastal regions

Volatile oils, flavonoids, alkaloids, terpenoids, tannin

Antimicrobial, used as a traditional oral hygiene aid

Neem tree/margosa tree

Azadirachta indica

Native to Burma, found all over India

Terpenoids

Antimicrobial, antifungal, antiviral, antipyretic, antiinflammatory, antioxidant

Indian mulberry

Morinda citrifolia

Sub-Himalayan tracts, Darjeeling, Konkan

Anthraquinones, lignans, flavonoids

Anti-inflammatory

Green tea

Camellia sinensis

Cultivated in Assam, Darjeeling

Polyphenols

Stimulant, diuretic, astringent, anticancer effects

Propolis

Resinous mixture that honey bees collect from tree buds, sap flows, or other botanical sources.

Flavonoids

Antimicrobial, antiinflammatory, anesthetic, cytostatic and cariostatic

Sr. No Plants reviewed (common name)

Chamomile (German chamomile)

Botanical name of plants Geographical habitat

Matricaria chamomilla

neem leaf extract and 2% sodium hypochlorite against Enterococcus faecalis, Candida albicans and mixed culture, it was concluded that neem leaf extract has a significant antimicrobial effect against all the microorganisms. Use of neem as an endodontic irrigant might be advantageous because it is a biocompatible antioxidant and thus not likely to cause the severe injuries to patients that might occur via NaOCl accidents [26]. Similarly, propolis and Morinda citrifolia juice were found to be effective against E. faecalis in dentine of extracted teeth as antimicrobial irrigant [27]. Green tea polyphenols, the traditional drink of Japan and China, is prepared from the young shoots of the tea plant Camellia sinensis. The antimicrobial activity is due to inhibition of bacterial enzyme gyrase by binding to ATP-B subunit. Green tea exhibits antibacterial activity on E. faecalis plaknotic cells. It is also found to be a good chelating agent [28]. It is proven to be safe, containing active constituents that have beneficial physiologic effect apart from its curative property such as antioxidant, antiinflammatory and radical scavenging activity and may have an added advantage over the traditional root canal irrigants [29].

Propolis is resinous material/sap that is collected after it oozes out from tree bark and bud. After bees have collected propolis they mix it with wax flakes and their saliva in the hive. This mixture is what they use to cover the interior of the hive. The bees not only use propolis as a building material and structural defense mechanism but their health is maintained as a result of its immune system enhancing properties. Propolis forms the bees’ external immune defense system, making the beehive one of the most sterile environments known to nature. It is known that propolis exhibits several pharmacological properties such as antimicrobial, antiinflammatory, healing, anesthetic, cytostatic and cariostatic properties [30]. The results of an in vitro analysis showed that the antibacterial activity of propolis against E. faecalis was between calcium hydroxide and chlorhexidine [31].

Intracanal medicaments Intracanal medicaments are routinely employed in endodontic therapy. The main reasons for their use include the



Table 2

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Intracanal medicaments.

Sr. No Plants reviewed (common name) Propolis

Botanical name of plants

Geographical habitat

Resinous mixture that honey bees collect from tree buds, sap flows or other botanical sources.

Common or great Arctium lappa burdock

Native to northern Europe; found in western Himalayas, Kashmir and Shimla.

elimination or reduction of microorganisms, rendering canal contents inert and prevention of post-treatment pain. The chemical nature of medicaments employed as intracanal dressings is varied. They come from a number of different groups. Often, different chemicals or drugs are combined in a “cocktail” in an attempt to elicit a variety of effects with a single application [32]. However, the toxicity and potential allergenicity of the commonly used intracanal medicaments, particularly those of the phenolic and aldehyde derivatives has paved way for new research into herbal medicament usage (Table 2). Propolis has been used as an intracanal medicament for endodontic purpose in various trials. It was found that propolis exhibited good in vitro antibacterial activity against E. faecalis in root canals, suggesting that it could be used as an alternative intracanal medicament [33]. Rezende et al. evaluated the antimicrobial activity of two experimental pastes containing propolis extract associated with calcium hydroxide in primary molars of 4- to 8-year-old children. They concluded that the association between propolis and calcium hydroxide was effective in controlling dental infections in vitro [34]. Arctium lappa is a plant that is widely used in folk medicine all over the world for its well-known therapeutic applications. It has antibacterial and antifungal activity, diuretic, antioxidant and anxiolytic action, platelet anti-aggregating effect and HIV-inhibitory action. In dentistry, A. lappa has been investigated due to its antimicrobial potential against oral microorganisms, specifically those associated with endodontic infections [29]. Pereira et al. evaluated in vitro antimicrobial activity of rough extracts from leaves of A. lappa against E. faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and C. albicans. They concluded that A. lappa constituents exhibited a great microbial inhibition potential against the tested endodontic pathogens [35].

Active constituent

Action

Flavonoids

Antimicrobial, anti-inflammatory, anesthetic, cytostatic and cariostatic

Polyacetylene, tannins, terpenoids

Roots-tumor growth inhibitor, cardiac stimulant, diuretic, spasmolytic. Leaves and seeds – anti-inflammatory

Pulp-capping agents There are various materials in routine use for pulp capping, the aim being to induce reparative dentinogenesis across the exposed pulp. Calcium hydroxide is generally accepted as the material of choice. Numerous researchers have advocated direct bonding of pulp exposure although this remains controversial [36]. Herbal products may also be a viable option for pulp capping. Propolis is the most investigated plant product in this regard. Parolia et al. investigated the response of human pulp tissues that were mechanically exposed to propolis and compared it with two existing and commonly used pulpcapping agents [mineral trioxide acetate (MTA) and Dycal]. There was more pulp inflammation in teeth treated with Dycal than with propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp-capping material than teeth treated with Dycal on the 45th day. The response of pulps to propolis as a pulpcapping agent was comparable to MTA and Dycal [37].

Retreatment agents A certain number of cases do not respond to initial endodontic therapy for many reasons; retreatment becomes necessary. Retreating previously filled canal systems demands that antimicrobial irrigants and medicaments gain access to all ramifications of the canal system that may be harboring organic matter and microorganisms. Various removal methods are available, including the use of solvents, heat and mechanical instrumentation, alone or in combination. Solvents are essential for the thorough cleaning of filling material/debris and effective disinfection of the root canal system. Many herbal preparations like Blue-Gum tree oil and Orange oil have been investigated for endodontic retreatment utilizing the solvent actions of the oil (Table 3).


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Table 3


Retreatment agents.




Active Action constituent

Blue-gum tree (Australian gum tree/ Neelgiri oil)

Eucalyptus globules

Native to Australia; cultivated mainly at the hill-stations of India

Flavonoids

Essential oil from leaves – antiseptic, antibiotic, antiviral, antifungal, antispasmodic, decongestant, antiasthmatic

Orange

Citrus aurantium

Cultivated in Khasi hills and Guntur (Andhra Pradesh).

Terpenoid

Essential oil is used as solvent

Eucalyptus oil and orange oil were reported as being as effective as chloroform and xylene to dissolve or soften gutta-percha. Orange oil is readily available, inexpensive, and displays a solvent effect that is close to that of chloroform. In addition, it has antimicrobial activity. Orange solvent has the advantage over other plantderived solvents such as eucalyptus oil in that its viscosity is closer to that of water and it can thus easily be administered through an endodontic irrigating syringe. In addition, orange solvent has a pleasant smell, which is easily acceptable to patients [38, 39]. Dental traumatology Dental avulsion is a traumatic injury characterized by the complete displacement of the tooth from its socket, with damage to the periodontal ligament, cementum, alveolar bone, gingival and pulp tissues. The most Table 4

indicated procedure for this kind of dental trauma is re-implantation, which is a surgical technique consisting of reinserting a tooth in its socket after it has been extracted on purpose or accidentally [40]. Healing following avulsion and replantation is dependent on the extent of pulpal and periodontal ligament tissue damage. Therefore, immediate replantation is the recommended treatment of choice for an avulsed permanent tooth. To achieve a more favorable prognosis following tooth replantation, use of an appropriate interim transport medium is usually advocated. Numerous studies have researched and advocated the use of media like saliva, milk, Hank’s balanced salt solution (HBSS) and ViaSpan. However, current research has indicated the use of newer herbal agents as promising interim transport media for an avulsed tooth [41]. The plant based herbal media in this regard includes popolis, red mulberry juice, garden sage extracts, coconut water and GTEs (Table 4).

Storage media in dental traumatology.




Active constituent

Action

Flavonoids


Anthocyanosides

Fruit – mild laxative. Leaves and root bark – expectorant, diuretic and hypotensive. Leaf – anti-inflammatory

Propolis

Resinous mixture that honey bees collect from tree buds, sap flows, or other botanical sources.

Red mulberry

Morus rubra

Native to eastern North America, Florida and Texas

Garden sage

Salvia officinalis

Native to the Essential oil constituents Mediterranean region; grown as an ornamental plant

Coconut plant

Cocos nucifera

Cultivated chiefly in Kerala, Tamil Nadu and Karnataka

Flavonoids, alkaloids, steroids, saponin

Coconut water contains sugar, fiber, proteins, antioxidants, vitamins and minerals, and provides an isotonic electrolyte balance; consumed as a refreshing drink

Green tea

Camellia sinensis


Polyphenols



Plant – astringent, anti-inflammatory, antispasmodic, antiseptic. Used for sore throat, laryngitis, tonsillitis, stomatitis


The efficacy of propolis extract in maintaining the viability of human periodontal ligament (PDL) cells was evaluated in dogs after storage in this extract. The in vitro results showed that the efficacy of propolis in maintaining functional viability of PDL cells was similar to that of milk. The in vivo results showed that teeth maintained in propolis medium exhibited replacement resorption with significant reduction in tooth length, similar to teeth maintained in saliva and dried teeth [42]. Mori et al. evaluated propolis as storage media for avulsed teeth and the ideal time period for keeping the tooth inside it. According to the results of this study, the use of propolis as a storage media for maintaining avulsed teeth could be highlighted, and the 6-h period was more appropriate [43]. Ozan et al. determined the ability of the juice of Morus rubra fruit to serve as a temporary storage medium for the maintenance of PDL cell viability of avulsed teeth. Results showed that the efficacy of 4.0% and 2.5% M. rubra at 3, 6 and 12 h was found to be significantly better than HBSS. At 24 h, 4% M. rubra was found to be similar to HBSS. Thus the results showed that juice of the fruit sample of M. rubra studied at a concentration of 4% was a more effective storage medium than other groups. Hence the juice of the fruit of M. rubra can be recommended as a suitable transport medium for avulsed teeth [44]. Polat et al. determined the ability of Salvia officinalis extracts to serve as a storage medium for the maintenance of PDL cell viability of avulsed teeth. The results showed 2.5% S. officinalis was a more effective storage medium than the other experimental solutions [45]. In another investigation, skimmed and whole milk, followed by natural coconut water and HBSS, were the most effective media in maintaining cell viability of PDL fibroblasts [46]. GTE has been reported to have remarkable antiinflammatory, antioxidant and anticarcinogenic effects. Hwang et al. investigated in vitro the efficacy of GTE as a storage medium for avulsed teeth. The result indicates that there was no difference in cell viability between GTE and HBSS media, whereas GTE showed higher cell viability than other media. Thus, efficacy of GTE in maintaining the viability of human PDL cells is similar to that of HBSS and higher than that of milk. Therefore, it was concluded that GTE could be a suitable, alternative storage medium for avulsed teeth [47].

Dental caries prevention Ubiquitousness and increasing prevalence of dental caries makes it one of the most important problems in public health. Due to high cost and lack of resources at primary

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level, prevention is better in dental caries. Since the origin is related to bacteria, antibacterial therapy is mainstay of treatment [48]. Lack of high efficacy with antibacterial agents, unwanted effects and resistance to these agents are drawing attention of scientists to search for new and better drugs. Plant products are currently gaining attention for treatment of various ailments including dental diseases. Although fluoride, delivered in various modalities, remains the mainstay for the prevention of caries, additional approaches are required to enhance its effectiveness. Natural products offer a rich source of structurally diverse substances with a wide range of biological activities, which could be useful for the development of alternative or adjunctive anticaries therapies. Phytomedicinals may aid in dental caries prevention as well as treatment by combating bacteria. However, it is a challenging approach owing to complex chemistry and isolation procedures to derive active compounds from natural products. Nevertheless, natural substances potentially active against virulent properties of cariogenic organisms have been identified like garlic, peppermint, clove, turmeric, green tea, neem tree and so on (Table 5). It is postulated that the phytomedicinals aid in dental caries prevention as well as treatment by combating bacteria through various modes as follows [19, 49]: – Inhibitors of bacterial growth – Inhibitors of acid production and acidurance – Inhibition of exopolysaccharide synthesis – Inhibition of bacterial adherence – Increase the susceptibility of the microorganism through action of secondary metabolites [49] When the antimicrobial activity of garlic on oral pathogens associated with dental caries was evaluated, it was effective against gram-positive species S. mutans and Streptococcus sobrinus. These results support the traditional medicinal use of garlic and suggest the use of allicin which is considered the most therapeutic constituent of garlic for alleviating dental diseases [50]. Chen et al. examined the effects of filtered garlic extracts on the acid production and the growth of S. mutans. Results showed that garlic extracts could enhance the rate of acid production and inhibit the growth of S. mutans. They concluded that despite the stimulation of acid production, garlic might prevent dental caries by the stimulation of salivary secretion and inhibition of bacterial growth in the oral cavity. Thus, garlic may have potential to prevent dental caries [51]. Rasooli et al. assessed the antimicrobial and biofilm formation preventive properties of Mentha piperita and Rosmarinus officinalis essential oils and chlorhexidine


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Table 5


Dental caries prevention. Botanical name of plants


Garlic

Allium sativum

Native to Central Asia, Alkaloids, saponins, steroids, cultivated all over India lipids, flavonoids

Antibiotic, bacteriostatic, fungicide, antithrombic, hypotensive, hypoglycemic, antimicrobial

Peppermint

Mentha piperata

Native to Europe; cultivated in Maharashtra, Kashmir and Punjab

Oil – digestive, mild sedative, antiseptic, antiviral, the essential oil has both antibacterial and antifungal properties

Clove

Syzygium aromaticum

Cultivated in Tamil Nadu Volatile oil, tannins and Kerala

Turmeric

Curcuma longa

Cultivated all over India, Tarmins particularly in West Bengal, Tamil Nadu and Maharashtra

Green tea

Camellia sinensis


Propolis

Resinous mixture that honey bees collect from tree buds, sap flows or other botanical sources.

Neem tree/ margosa tree

Azadirachta indica



against S. mutans and Streptococcus pyogenes. The minimal bactericidal concentrations of the M. piperita and R. officinalis oils and chlorhexidine were 6,000, 2,000, 8,000 ppm and 1,000, 4,000, 1,000 ppm for S. mutans and S. pyogenes, respectively [52]. The anti-cariogenic properties of clove extracts was investigated for cell adhesion, cell-surface hydrophobicity and glucan synthesis activities of S. mutans. The extracts were found to reduce the synthesis of water insoluble glucan by almost 50% at a concentration as low as 0.5 mg/mL. The findings indicate that clove extracts exert inhibitory effects on the cariogenic properties of S. mutans [53]. Kim et al. evaluated the antibacterial effects of turmeric on a S. mutans biofilm by examining the bactericidal activity, inhibition of acidogenesis and morphological alteration. It showed similar bactericidal effect to that of chlorhexidine but the dose of turmeric was one twentieth that of chlorhexidine. Turmeric has strong bactericidal activity, inhibitory effects on acidogenesis, and alters the microstructure of S. mutans biofilm. Thus, turmeric has potential in anti-S. mutans therapy for the prevention of dental caries [54].

Active constituent

Volatile oil containing menthol

Action

Anti-inflammatory, antibacterial. Oil is employed as a local analgesic for hypersensitive dentine and carious teeth Antibacterial, antiseptic

Polyphenols


Flavonoids


Terpenoids

Antimicrobial, antifungal, antiviral, antipyretic, antiinflammatory

Miller et al. reviewed that various components in green and black teas, notably simple catechins, have properties in vitro that suggest an anti-cariogenic activity. These include [24]: – a direct bactericidal effect against S. mutans and S. sobrinus; – prevention of bacterial adherence to teeth; – inhibition of glucosyltransferase, thus limiting the biosynthesis of sticky glucan; – inhibition of human and bacterial amylases. Studies in animal models show that these in vitro effects can translate into caries prevention. A limited number of clinical trials in man suggest that regular tea drinking may reduce the incidence and severity of caries. If substantiated, this could offer a very economical public health intervention [55]. Libério et al. reviewed the in vitro and in vivo effects of propolis on S. mutans growth, bacterial adherence, glucosyltransferase activity and caries indicators. Investigations carried out with crude propolis extracts, isolated fractions and purified compounds showed reductions in S. mutans



counts and interference with their adhesion capacity and glucosyltransferase activity, which are considered major properties in the establishment of the cariogenic process. Data from in vivo studies have demonstrated reductions in S. mutans counts in saliva, the plaque index and insoluble polysaccharide formation. These findings indicate that propolis and/or its compounds are promising cariostatic agents. However, the variation in the chemical composition of propolis due to its geographical distribution is a significant drawback to its routine clinical use. Thus, further studies are needed to establish the quality and safety control criteria for propolis in order for it to be used in accordance with its proposed activity [56]. A study was conducted to evaluate the antimicrobial effects of neem on the microorganisms S. mutans, Streptococcus salivarius, Streptococcus mitis and Streptococcus sanguis that are involved in the development of dental caries. Neem extract produced the maximum zone of inhibition on S. mutans at 50% concentration. Even at 5% concentration neem extract showed some inhibition of growth for all the four species of organisms [57]. Vanka et al. evaluated the antibacterial effect of neem mouthwash against salivary levels of S. mutans and lactobacillus tested over a period of 2 months. Also its effect in reversing incipient carious lesions was assessed. Results showed Table 6

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that S. mutans was inhibited by neem mouthwashes, with or without alcohol as well as chlorhexidine [58].

Herb based dental materials Traditional herbs have an array of applications as biomaterials. Almost all the modern dental materials have their roots in these phytocompounds. The commonly used materials in routine dental practice of herbal origin includes zinc oxide eugenol cement, impression materials (agar agar and alginate), gutta-percha root canal filling material, citric acid, camphorated monochlorophenol medicament and thymol (Table 6).

Herbs acting on oral mucosal lesions Mucosal lesions include gingivitis, apthous ulcers, thrush and various bacterial and viral lesions. Many of these conditions are self-limiting; consequently, herbal treatments are generally palliative in character. A variety of herbs are found to have a beneficial effect for treatment of these lesions like Aloe vera, rhatany, gum myrrh, licorice, myrtle, coriander, garlic, clove and so on (Table 7).

Herb based dental materials. Botanical name of plants


Active constituent

Dental material

Clove

Syzygium aromaticum

Cultivated in Tamil Nadu and Kerala

Volatile oil, tannins

Zinc oxide eugenol cement, constituent of endodontic sealers,

Palaquium gutta

Palaquium gutta

Southeast Asia and northern Australia, from Taiwan south to the Malay Peninsula and east to the Solomon Islands

Alkaloids, flavonoids

Gutta-percha – endodontic obturating material

Agar agar, Japanese ising

Gelidium amansii

Indigenous to Japan


Agar – impression material

Seaweed

Laminaria digitata

Brown alga found mostly on exposed sites on shores


Alginate – impression material

Lemon

Citrus limon

Cultivated all over India


Citric acid – periodontal root conditioning

Camphor tree

Cinnamomum camphora, Karpura

A tree native to China and Japan and often grown as a hedge plant.

Essential oil

CMCP (Camphorated monochlorophenol) – endodontic intracanal medicament

Mother of thyme

Thymus vulgaris

Native to North America; also found in temperate Himalayas from Kashmir to Nepal; grown in gardens in western India.

Terpenoid phenolic alcohol polyphenols Flavones

Thymol – used in mouthwashes



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Table 7


Treatment of oral mucosal lesions.




Active constituent Action

Herbs for recurrent apthous stomatitis treatment 1. Medicinal aloe Aloe vera Cultivated throughout India, wild Anthraquinone on coasts of Maharashtra, Gujarat and South India. Rhatany

Krameria triandra

Peru, Bolivia, India

Gum myrrh

Commiphora molmol

Arabian peninsula (Oman, Yemen) Volatile oil and Africa (Ethiopia, Somalia, Northeast Kenya)

Licorice

Glycyrrhiza glabra

Native to the Mediterranean regions, Punjab, Jammu and Kashmir and South India.

Glycyrrhizin, flavonoids

Demulcent, expectorant, anti-allergic, anti-inflammatory

Myrtle

Myrtus communis

Cultivated in gardens of Northwestern India and Tamil Nadu.

Phenolic compounds, flavonoids and anthocyanins

Leaves – antiseptic, antimicrobial, antiparasitic.

Herbs for candidiasis treatment Coriander Coriandrum sativum

Tannic acid

Emollient, anti-inflammatory, antimicrobial Astringent. Used topically for wounds; as a lozenge, gargle or mouthwash for gingivitis and pharyngitis Anti-inflammatory, antiseptic, bacteriostatic, antiviral, astringent

Triterpenoids, Cultivated chiefly in Madhya Pradesh, Maharashtra, Rajasthan, essential oils Andhra Pradesh, Tamil Nadu, Karnataka and Bihar

Stimulant, diuretic; hypoglycemic and anti-inflammatory. Oil is bactericidal

Garlic

Allium sativum

Native to Central Asia, cultivated all over India.


Antibiotic, bacteriostatic, fungicide, antithrombic, hypotensive, hypoglycemic, antimicrobial

Clove

Syzygium aromaticum

Cultivated in Tamil Nadu and Kerala

Volatile oil, tannins

Anti-inflammatory

Mild sedative, anxiolytic and hypnotic effects

Flavonoids, phenolic acids, terpenes

Mild sedative, anxiolytic and hypnotic effects

Herbs for viral lesions treatment Lemon balm Melissa officinalis Peppermint

Mentha piperata

Herbs for lichen planus treatment Medicinal aloe Aloe vera

Native to Europe; cultivated in Volatile oil Maharashtra, Kashmir and Punjab. containing menthol

Oil – digestive, mild sedative, antiseptic, antiviral, the essential oil has both antibacterial and antifungal properties

Cultivated throughout India, wild Anthraquinone on coasts of Maharashtra, Gujarat and South India.

Emollient, anti-inflammatory, antimicrobial

Little hogweed

Portulaca oleracea

All over India, cultivated as a vegetable.

Alkaloids, flavonoids, saponins, tannins, phenolic compounds

Mild spasmodic, diuretic. Used in scurvy and in diseases of liver, spleen, kidney and bladder; also in dysuria, stomatitis and dysentery. A paste of leaves is applied to swellings, erysipelas, burns and scalds.

Turmeric

Curcuma longa

Cultivated all over India, particularly in West Bengal, Tamil Nadu and Maharashtra

Tannins

Antibacterial, antiseptic



It has been reported that A. vera gel accelerates the healing of apthous ulcers and reduces the pain associated with them. Ninety patients with histories of recurrent apthous ulcers were separated into three groups, with each group receiving a different treatment (either acemannan hydrogel i.e. A. vera, freeze-dried acemannan hydrogel, or an unspecified over-the-counter product as an active control) four times a day. The groups using acemannan hydrogel in either form healed faster than those using the over-the-counter remedies. The report noted that compared with other remedies for apthous ulcers, the acemannan hydrogel did not have the disagreeable taste and texture associated with traditional therapies and did not sting when applied [59]. However, it has been reported that oral ingestion of A. vera may cause diarrhea, which in turn can lead to electrolyte imbalance, kidney dysfunction, dry mouth, headache and nausea, while topical application may induce contact dermatitis, erythema or phototoxicity. This necessitates further, well-designed trials with sufficient details of the contents of A. vera products to be carried out to determine the effectiveness. Rhatany has also been used in this regard. The biological action of rhatany is caused by the astringent rhataniatannic acid, which is similar to tannic acid. Infusions have been used as a gargle, a lozenge, especially when mixed with cocaine, as a local hemostatic and a remedy for diarrhea. When finely powdered, the dried roots furnished a frequent constituent of tooth powders [60]. It is frequently used in the form of a hydroalcoholic solution (tincture) as a treatment for various oral lesions. Used as such or combined with equal parts of myrrh tincture, it is applied locally to noninfectious canker sores with good results. Treatment is carried out two or three times daily. The tincture is also effective when used as a mouthwash, five to ten drops being added to a glass of water to be functional [61]. Moghadamnia et al. evaluated the efficacy of licorice bioadhesive hydrogel patches to control the pain and reduce the healing time of recurrent apthous ulcer. Licorice patches caused a significant reduction in the diameter of the inflammatory halo and necrotic center compared with the placebo group. According to the results of this study, licorice bioadhesive hydrogel patch can be effective in the reduction of pain and of the inflammatory halo and necrotic center of apthous ulcers [62]. The clinical efficacy of a paste containing Myrtus communis (Myrtle) in the treatment of recurrent apthous stomatitis was evaluated. The data indicated a significant reduction of ulcer size, pain severity, erythema and

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exudation level with the paste. Also, the patients’ overall assessment of treatment improved after applying paste containing myrtle. No side effects were reported [63]. The efficacy of extracts from Coriandrum sativum was evaluated against Candida species isolates from the oral cavity of patients with periodontal disease. The oil affected the biofilm formation in C. albicans causing a decrease in the biofilm growth. The activity of C. sativum oil demonstrated in this study showed its potential as a new natural antifungal formulation [64]. Mazzanti et al. evaluated the antiviral activity of a hydroalcoholic extract of lemon balm. It was found that the cytopathic effect of herpes simplex virus (HSV-2) was reduced with the use of lemon balm. The maximum inhibiting effect (60%) was obtained with 0.5 mg/mL. The authors support the use of lemon balm for treating herpes simplex lesions and encourage clinical trials on this medicinal plant [65]. Similarly, Schuhmacher et al. examined the virucidal effect of peppermint oil against herpes simplex virus. The 50% inhibitory concentration of peppermint oil for herpes simplex virus plaque formation was determined to be 0.002% and 0.0008% for HSV-1 and HSV-2, respectively. Peppermint oil exhibited high levels of virucidal activity against HSV-1 and HSV-2 in viral suspension tests. Considering the lipophilic nature of the oil that enables it to penetrate the skin, peppermint oil might be suitable for topical therapeutic use as virucidal agent in recurrent herpes infection [66]. Hosseini et al. evaluated the effectiveness of purslane in the treatment of oral lichen planus (OLP). Approximately 83% of the purslane patients showed partial to complete clinical improvement but 17% had no response. A partial to complete response was observed in all purslane treated patients. According to these findings purslane is clinically effective in the treatment of OLP [67].

Surgical uses The use of phytocompounds has shown promising results in enhancing wound healing as well as for reducing postoperative complications. Some patients have a tendency to bleed excessively after dental surgery for a variety of reasons, making oral surgical procedures more risky for these patients. In this regard, a phytomedicinal hemostat would be an appreciated addition to the surgical armamentarium. Ankaferd Blood Stopper® (ABS) is a unique folkloric medicinal plant extract. The basic mechanism of action of


246


ABS is through the formation of encapsulated protein network providing focal points for vital erythrocytes to aggregate on. The ABS induced protein network formation involves blood cells, particularly erythrocytes, without affecting the physiological individual coagulation systems. ABS is a standardized extract from the following plants: Thymus vulgaris, Glycyrrhiza glabra, Vitis vinifera, Alpinia officinarum and Urtica dioica in a weight ratio of 6:8:7:7:5, respectively. Baykul et al. determined the efficacy of the topical application of ABS on hemorrhagic diathesis following dental procedures under different conditions. ABS was found to be effective within 10–20 min in controlling bleeding in most of the patients after dental surgery. These observations suggest the use of ABS may be a beneficial hemostatic agent for use in patients with hemorrhagic diathesis following tooth extraction. Additional research is needed to clarify the role of this unique medicinal product in the surgical treatment of dental patients with bleeding tendency [68]. Plants have also been used as wound-healing agents. A study was conducted to compare the incidence of alveolar osteitis (AO) in patients treated with either clindamycin-soaked Gelfoam (Pharmacia and Upjohn Co., Kalamazoo, MI) or SaliCept Patches (Carrington Laboratories, Inc., Irving, TX). The SaliCept Patch is a freeze-dried pledget that contains Acemannan Hydrogel (Carrington Laboratories) obtained from the clear inner gel of A. vera L. A retrospective evaluation was performed of the records of 587 patients (1,031 sockets) whose extraction sites had been treated with clindamycinsoaked Gelfoam. A prospective trial was conducted in which 607 patients (1,064 sockets) had two SaliCept Patches placed immediately after extraction. Analysis restricted to mandibular third molar sites showed that 78 of 975 sites (8.0%) in the Gelfoam group developed AO, whereas only 11 of 958 sites (1.1%) in the SaliCept group developed AO (p < 0.0001). Further analysis of all extraction sites revealed that the incidence of AO in the Gelfoam group was 7.6% compared with 1.1% in the SaliCept-treated group (p < 0.0001). The study results suggested that the SaliCept Patch significantly reduces the incidence of AO compared with clindamycin-soaked Gelfoam [69]. The effect of oral and topical application of Calendula officinalis flower extract on excision wounds of Wistar rats was investigated. The day on which the wound was made was considered day 0. Four groups of six animals each were used, of which group I served as untreated control. Groups II and III received 20 and 100 mg/kg b.wt extract orally for 10 consecutive days. Group IV received

a topical application of Calendula extract. On the fourth day, extract treatment produced 43.5% and 60.7% wound closure, and topical application produced 42.2% wound closure, which was significantly higher than the wound closure (32.4%) of the untreated control animals. By eighth day, about 90% of the wound was healed in the extract-treated groups whereas for the control healing was only 51.5%. It was found that 100% wound closure was observed at 20th day in groups III and IV. The data indicated potent wound-healing activity of C. officinalis extract. The authors suggested that Calendula extract treatment to promote the wound to heal much faster is attributable to its capability to enhance the synthesis of connective tissue, especially collagen. This view is supported by the increased hydroxyproline content of granuloma tissue directly indicating the rate of collagen synthesis. Hexosamine, the ground substratum for collagen synthesis, has been shown to increase during the early stages of wound healing and to decrease thereafter. According to the authors, the results obtained in this study showing a significant increase in the level of hexosamine in the drug-treated groups on the initial days could be correlated with the wound-healing efficiency of the drug [70]. Duarte et al. evaluated the effect of Chamomilla recutita on the healing of ulcers in rats. Animals treated with chamomile showed the best results regarding epithelialization and percentage of collagen fibers after 10 days [71]. Another agent Curcumin was shown to be effective in reducing wound-healing time, improving collagen deposition and increasing fibroblast and vascular density in wounds thereby enhancing both normal and impaired wound healing. Curcumin also has beneficial effect as a proangiogenic agent in wound healing by inducing transforming growth factor-beta, which induces both angiogenesis and accumulation of extracellular matrix, which continues through the remodeling phase of wound repair [72].

Periodontal uses Gingivitis is a chronic inflammatory process limited to the gingiva, without either attachment or alveolar bone loss. It is one of the most frequent oral diseases, affecting more than 90% of the population, regardless of age, sex or race. The prevention of gingivitis by daily and effective supragingival plaque control using toothbrushing and dental floss is necessary to arrest a possible progression to periodontitis [73]. Although mechanical plaque control methods have the potential to maintain adequate levels



of oral hygiene, clinical experience and population-based studies have shown that such methods are not being employed as accurately as they should by a large number of people. Therefore, several chemotherapeutic agents such as triclosan, essential oils and chlorhexidine have been developed to control bacterial plaque, aiming at improving the efficacy of daily hygiene control measures. The interest in plants with antibacterial and anti-inflammatory activity has increased as a consequence of current problems associated with the wide-scale misuse of antibiotics that induced microbial drug resistance. Natural products such as Astronium urundeuva, Calendula, A. vera, Curcuma zedoaria and other herbal products have been tested with effective results [74, 75]. A wide range of antimicrobial agents and herbal products are added to dentifrice and mouth rinsing solutions with the aim of preventing caries or biofilm formation [76]. Among the herbal products available in the market today, Parodontax® (GlaxoSmithKline, Middlesex, UK) has been widely tested in dentistry. Besides sodium bicarbonate and sodium fluoride (1,400 ppm), it contains the following herbal products: Matricaria chamomilla (Asteraceae) has anti-inflammatory properties that reduce gingival inflammation; Echinacea purpurea (Asteraceae) stimulates immune response; S. officinalis (Lamiaceae) has antihemorrhagic properties; Commiphora myrrha (Burseraceae) has natural

Table 8

247

antiseptic properties and M. piperita (Lamiaceae) has analgesic, antiseptic and anti-inflammatory properties. Ozaki et al. reported that both Parodontax® and a triclosan dentifrice were effective in reducing plaque and gingival indices [77]. Pistorius et al. reported a significant reduction in gingival index for an herbal-based mouthrinse containing S. officinalis, M. piperita, menthol, M. chamomilla, C. myrrha, Carum carvi (Umbelliferae), Eugenia caryophyllus (Myrtaceae) and E. purpurea. They concluded that the mouthrinse could be used daily in patients with periodontal diseases as an adjunctive procedure to reduce gingival inflammation [76]. The commonly investigated phytomedicinals in this regard are medicinal aloe, bloodwort, neem tree, mustard tree, pomegranate and Indian gum tree (Table 8). A mouthrinse containing A. vera was found to reduce gingival inflammation and gingival bleeding and was more effective than Listerine® in reducing counts of aerobic, microaerophilic and anaerobic bacteria [78]. A. vera as a tooth gel is intended to perform the same function as tooth paste which is to eliminate disease causing bacteria in the mouth. A. vera in tooth gel is used to cleanse teeth and gums as effectively as toothpaste does. Because A. vera tooth gel does not contain the abrasives found in most toothpaste, it is less harsh on teeth and is a great alternative for people with sensitive teeth or gums. The antimicrobial efficacy of A. vera tooth gel (Forever Bright,

Periodontal therapy.


Botanical name Geographical habitat of plants

Active constituent

Action

Medicinal aloe

Aloe vera

Cultivated throughout India, wild on coasts Anthraquinone Emollient, anti-inflammatory, of Maharashtra, Gujarat and South India. antimicrobial

Bloodwort

Sanguinaria canadensis

Eastern North America, Canada, Florida

Alkaloids (primarily sanguinarine)

Antibacterial and antiplaque agent (approved by FDA)

Neem tree/margosa tree

Azadirachta indica


Terpenoids

Antimicrobial, antifungal, antiviral, antipyretic, antiinflammatory

Mustard tree (miswaak/tooth brush tree)

Salvadora persica

Arid regions, on saline lands and in coastal regions

Volatile oils, flavonoids, alkaloids, terpenoids, tannin

Antimicrobial, used as a traditional oral hygiene aid

Pomegranate

Punica granatam

Native to Iran; but cultivated throughout India.

Flavones, flavonols, alkaloids

Leaf – used in stomatitis (recommended by The Ayurvedic Pharmacopoeia of India).

Indian gum arabic tree

Acacia arabica

Throughout the drier parts of India

Flavonoids

Stembark – astringent, hypoglycemic. Gum – demulcent (soothing agent for inflammatory conditions)


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Forever Living Products, Scottsdale, AZ) and two popular tooth pastes, pepsodent (Unilever, Englewood Cliffs, NJ) and colgate (Colgate-Palmolive, Canton, MA), was compared, and it was found that A. vera tooth gel was as effective as two commercially popular tooth pastes in controlling all the organisms (S. mutans, C. albicans, Lactobacillus acidophilus, E. faecalis, Prevotella intermedia, Peptostreptococcus anaerobius and S. mitis) used in the study [79]. Studies on the plant extract sanguinarine have shown that it produces moderate reductions in plaque and gingivitis. The zinc present in the formulations could be partly responsible for the effect. Chemically, sanguinarine is a benzophenanthridine alkaloid derived from the alcoholic extraction of powdered rhizomes of the bloodroot plant, Sanguinaria canadensis, which grows in Central and South America and Canada. After precipitation and purification of the alcohol extract, an orange powder containing 30– 35% sanguinarine is obtained. Sanguinarine contains the chemically reactive iminiumion that is probably responsible for its activity. It appears to be retained in plaque for several hours after use and is poorly absorbed from the gastrointestinal tract. Several clinical studies have been carried out into its effects [80]. Pai et al. assessed the effectiveness of neem (A. indica) leaf extract against plaque formation in males between the age group of 20 and 30 years over a period of 6 weeks. A mucoadhesive dental gel containing A. indica leaf extract (25 mg/g) was formulated. The results suggested that the dental gel containing neem extract significantly reduced the plaque index and bacterial count than that of the control group [81]. S. persica is a medicinal plant whose roots have been used by many people in Africa, South America, Middle East and Asia. Babylonian 5000 BC recorded the precise method for the use of the miswak and the fashion ultimately spread throughout the Greek and Roman empire. In fact, the chewing stick which is known as miswak or siwak had fallen into general use by the time the holy prophet Mohammed started his mission in about 543 AD. Prophet Mohammed said that the miswak is an implement for the cleaning of teeth and pleases God [82]. Khalessi et al. compared the oral health efficacy of Persica mouthwash (containing an extract of S. persica) with that of a placebo, in a double-blind, crossover trial. Use of Persica mouthwash resulted in improved gingival health and lower carriage rate of cariogenic bacteria when compared with the pre-treatment values [83]. A hydroalcoholic extract of Punica granatum fruit (HAEP) was investigated for antibacterial effect on

dental plaque microorganisms. HAEP decreased the number of colony forming units of dental plaque bacteria by 84%, comparable to chlorhexidine (79% inhibition) but significantly better than the control rinse (11% inhibition). Both HAEP and chlorhexidine were effective against Staphylococcus, Streptococcus, Klebsiella and Proteus species, as well as Escherichia coli. The ellagitannin, punicalagin, is thought to be the fraction responsible for pomegranate’s antibacterial activity [84].

Herbs used in adjunct periodontal therapy The local delivery of antimicrobial therapy to periodontal pockets has the benefit of administering more drugs at the target site while minimizing the exposure of total body to the drug and the sustained release of antimicrobial in the periodontal pockets. Natural herbs are also known to halt the progression of periodontal disease. It was found that subgingival irrigation with an herbalbased mouthrinse in combination with an oral irrigator led to a significant reduction in both gingival index and sulcus bleeding index. An experimental local drug delivery system containing 2% whole turmeric (gel form) as an adjunct to scaling and root planning was found to be effective in causing significant reduction in plaque index, gingival index and sulcus bleeding index in a split mouth experimental design [76]. The authors recommended this as an adjunctive procedure to reduce gingival inflammation. A preliminary study by a group of Thai researchers investigated the effect of biodegradable chips impregnated with Centella asiatica and P. granatum pericarp on periodontal disease in patients with gum pocket depths of 5–8 mm. It was found that all treatment sites demonstrated a trend toward decreasing plaque and significant improvements were noted in pocket depth and attachment level at 3 months compared to placebo [85]. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission. Research funding: None declared. Employment or leadership: None declared. Honorarium: None declared. Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.



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Medicinal Plants: Their Use in Anticancer Treatment.

Use of medicinal plants by breast cancer patients in Algeria.

Folk use of medicinal plants in Karst and Gorjanci, Slovenia.

Indian Medicinal Plants.

Indian Medicinal Plants.

Neuroprotective effects of medicinal plants.

Antifertility activity of medicinal plants.

Indian Medicinal Plants: Part III.

Indian Medicinal Plants (Part II).

Medicinal plants: another man's poison.

Effect of medicinal plants on wound healing.

Antimalarial activity of Tanzanian medicinal plants.

Cytotoxicity potentials of eleven Bangladeshi medicinal plants.

Use of laser-induced breakdown spectroscopy for the detection of glycemic elements in Indian medicinal plants.

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Medicinal plants for renal injury prevention.

Pharmacologically active tannins isolated from medicinal plants.

Aromatic Medicinal Plants from Tajikistan (Central Asia).

Medicinal plants against hepatitis C virus.

Medicinal plants with potential anti-arthritic activity.