Clove stops toothache, dental problems

It is gaining popularity among herbal medicine practitioners and adherents for the treatment of toothache. But a new study by Indian and Malaysian researchers has shown that clove could be used not just for dental problems but also for cancer, hepatitis, as painkiller, anaesthetic, antibacterial, antiviral, antifungal, anti-inflammatory, and for cardiovascular diseases.

The new study published April 2015 in South African Dental Journal concluded: “Clove has many properties which have been identified in both basic and specific disease- targeted research that could be of benefit in the treatment of periodontal disease. Yet the review shows glaring gaps in research, which is specific to inflammatory periodontal disease.

“Eugenol, an important constituent of clove, has important anti-microbial and anti-inflammatory properties which could be harnessed and designed for the control and cure of periodontal disease. The fast developing fields of pharmaceutical and nano-technology are bound to impact on the designing of eugenol/clove extract formulations.

“There are opportunities wherein specific cell or tissue- targeting technology could effectively deliver the natural remedies in appropriate quantities and form. This will also negate the few cytotoxic properties of these compounds. Concerted effort is needed, as revealed by this review, to initiate investigations, which could bring the findings hidden on the research benches to effective clinical use. Interdisciplinary research especially between pharmacy and clinical periodontics is seriously advocated. This paper suggests that there will be merit in the return to natural medicine for the treatment of periodontal diseases.”

The study is titled “Potential of clove of Syzygium aromaticum in development of a therapeutic agent for periodontal disease: A review.”The researchers include: Senior Lecturer, Department of Clinical Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia,Dr. S. J. PulikottilI; and Senior Lecturer, Department of Periodontology, Vananchal Dental College, and Hospital, Farathiya, Garhwa, Jharkhand, India, S. NathII.

‘Perio’ means around, and ‘dontal’ refers to teeth. Periodontal diseases are infections of the structures around the teeth, which include the gums, periodontal ligament and alveolar bone. In the earliest stage of periodontal disease- gingivitis- the infection affects the gums. In more severe forms of the disease, all of the tissues are involved. It has been shown that if untreated, periodontal disease like gingivitis and periodontitis can eventually lead to tooth loss and other health problems.

Commonly called clove, Syzygium aromaticum (formerly Eugenia aromaticum) belongs to the plant family Myrtaceae. The locals, especially in Lagos call it konofro. It is used as one of the ingredients in preparing the local Zobo drink. The dried flower buds are used in making the popular local drink. Previous studies had validated cloves as next novel drug for epilepsy, convulsion, toothache, tuberculosis, measles and erectile dysfunction.

Also, several studies, including the World Health Organisation (WHO) monographs on selected medicinal plants have validated the folklore uses of cloves in treating microbial infections such as Staphylococcus aureus, Mycobacterium tuberculosis (causative organism for tuberculosis), herpes, polio, measles virus; epilepsy, seizures, convulsion, toothache, ulcer, constipation, sleeplessness (insomnia) and erectile dysfunction.

Antibacterial activity
Natural remedies have been used for a long time for the treatment of various bacterial infections. In the recent practice of medicine, the misuse of antibiotics has led to the development of bacterial resistance. Therefore there is a need for identifying novel antibacterial agents against which there is minimal or no bacterial resistance.

Studies on clove oil or its extract may contribute to the development of novel antimicrobial agents to offset the effects of resistance to antibiotics. Essential oils have anti-quorum sensing activity, which might be important in reducing the virulence and pathogenicity of drug-resistant bacteria. (Quorum sensing is a means of bacterial intercellular communication. Anti-quorum sensing interrupts that process). A combination therapy of clove with antibiotics could be another method of overcoming bacterial resistance.

Several studies have shown the effectiveness of clove against numerous strains of bacteria. Clove oil and eucalyptus oil exhibited antibacterial properties against the most common oral pathogen S. Mutans. Cai and Wu showed preferential growth-inhibition activity of a crude extract of clove against the gram-negative oral pathogens: Porphyromonas gingivalis, Streptococcus mutans, Actinomyces viscosus and Prevotella intermedia. Several other studies have confirmed the in vitro antibacterial activity of clove against gram-negative bacteria like Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa, Proteus vulgaris, Campylobacter jejuni, and Salmonella enteritidis, and gram-positive bacteria like Bacillus subtilis and Staphylococcus aureus. Duraipandiyan, Ayyanar and Ignacimuthu observed antibacterial activity against Bacillus subtilis, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, Ervinia sp, and Proteus vulgaris.

Antifungal activity
Clove possesses fungicidal characteristics in vitro and in vivo due to its phenolic components, carvacrol and eugenol. The potential drawback in the treatment of fungal diseases is the possibility of the development of antimicrobial resistance. Combination therapy with clove could form an alternative treatment method especially in treating fluconazole-resistant or multi-drug resistant fungal diseases. Studies have shown synergistic interaction with the use of eugenol and/or methyl-eugenol or either in combination with fluconazole or amphotericin B.

Antiviral activity
Viruses are highly sensitive to the components of essential oils. The antiviral activity of eugenol has been tested against the herpes simplex-1 (HSV-1) and HSV-2 viruses. Hussein, Miyashiro, Nakamura et.al found that Syzygium aromaticum extract was highly active at inhibiting replication of the hepatitis C virus. Synergistic interaction between acy-clovir and eugenol combination has been seen.

Analgesic activity
For many ages eugenol has been used as a natural remedy for relieving tooth pain. Similarly this technique in modern dental practice has been adopted by many clinicians, in which eugenol can act as an analgesic agent. Eugenol exhibited an analgesic effect in different experimental pain models in mice. Kurian and co-workers studied the anti-nociceptive ability of eugenol (100mg/kg) in several mouse models and found that the effect was more pronounced in the inflammatory phase than the neurogenic phase. Eugenol can, however, alleviate neuropathic pain. Guenette, Beaudry, Marier et al. in their study in male Sprague-Dawley rats, showed that eugenol, at a dose of 40mg/kg, was capable of prolonging reaction time to thermal stimuli. All these results suggested the possible use of eugenol as an analgesic agent.

Anaesthetic activity
Eugenol is cheap and is an easily available topical anaesthetic. It is relatively user-friendly and can be used effectively in lower concentrations than other local anaesthetics. It is rapidly metabolized and excreted, thus requiring no withdrawal period. Eugenol shows good anaesthetic effects on inflamed pulpal tissues.

Anti-tumour (cancer) activity
Clove essential oil has been reported to show anti-carcinogenic and anti-mutagenic potential. To overcome the toxic effects of synthetic drugs, clove essential oil can be used to inhibit, delay, block, or reverse the initiation of and promotional events associated with carcinogenesis. Sesquiterpenes found in Syzygium aromaticum were investigated as potential anticarcinogenic agents. Volatile oils display cytotoxic action towards the human tumour cell lines PC-3 and Hep G2 50. A derivative of eugenol, dihydro-eugenol, has been shown to induce apoptosis of human cancer cells. Studies have demonstrated that eugenol provides protection from chemically induced skin cancer.

Cardiovascular activity
The consumption of polyphenol-rich foods like clove can lower the risks for cardiovascular disease, arterial sclerosis and other disease related to oxidative stress. Eugenol produces dose-dependent, reversible vasodilator responses, negative inotropic effects in heart muscle, hypotensive effects and smooth muscle relaxant effect.
Potential of clove for treatment of periodontal disease

Clove exhibited antibacterial activity against gram-negative anaerobic periodontal pathogens, including Porphyromonas gingivalis and Prevotella intermedia. Clove may reduce periodontal inflammation by modulation of the signalling pathway (NF-kB); and suppression of IL-6, COX-2 and TNF-α.52-55 Besides its anti-inflammatory properties, clove also has antioxidant property. It has an important property for reducing the oxidative stress, which is often seen in periodontal disease. It promotes DPPH scavenging activity, hydroxyl radical scavenging and inhibits lipid peroxidation. It exhibits antifungal activity against Candida albicans (causes thrush) and antiviral activity against Herpes simplex virus (HSV) 1 and 2. Analgesic and anaesthetic properties of clove could be a natural way of performing painless dental and oral procedures. Additionally, Karmarkar, Choudhury, Das et al. observed that dried clove buds rich in eugenol and eugenol derivative were effective in preventing bone loss and this property would be beneficial for treating periodontal disease.

All these studies demonstrated that therapy with clove and its active components like eugenol can be beneficial for the treatment of periodontal disease as a natural anti-plaque or anti-gingivitis agent. Research has been particularly lacking in the areas of periodontal disease control. Clove can be effectively incorporated in therapeutic agents formulated against periodontal diseases in the form of mouthwashes, toothpastes, topical agents and local drug delivery devices.
Cytotoxicity of clove

Clove oil and its components are generally recognized as ‘safe’, but the in vitro study by Prashar et al. demonstrated cytotoxic properties of both the oil and eugenol towards human fibroblasts and endothelial cells. The cytotoxicity may be a function of more than one component. Clove oil was found to be highly cytotoxic at concentrations as low as 0.03 per cent (v/v) with up to 78 per cent of this effect attributable to eugenol and phenolic terpene. The second component β-caryophyllene did not contribute towards cytotoxicity. Localised irritation of the skin, ulcer formation, allergic contact dermatitis, tissue necrosis, reduced healing and in rare cases even anaphylactic-like shock are some the observed reactions when using dental products containing eugenol. Hartnoll, Moore and Douek reported severe side effects after clove oil ingestion such as hepatotoxicity, generalized seizures and disseminated intravascular coagulopathy. Further research is still required to clearly define the cytotoxic effects of clove.