Chewing sticks are popular components of the oral hygiene story in Africa. Studies have even suggested that chewing sticks, also called miswaks, are better than toothbrushes in keeping the teeth clean and ensuring oral hygiene. Well, no matter your opinion on this, the fact is that chewing stick is popular among Africans and it has proved to be good in ensuring oral hygiene.
But do you know that chewing stick has chemical constituents that make it very effective in keeping the teeth germ-free? Take a look at the research article below written by Muhammad Ajmal and published in the Journal of Pakistani Medical Association, you will see some amazing components of chewing stick that could prove why it is good for your teeth. Every person that wishes to keep good oral hygiene ought to read this article. It is part of a complete research work done to explain the components of chewing stick that make it amazing.
Chemical Constituents of Chewing-sticks
Some of the important constituents of the chewing-sticks are fluoride, silicone, alkaloids, essential oils (volatile oils), tannins, resins, gums, anthraquinones and related compounds (Table I). The beneficial effects of chewing-sticks in respect of oral hygiene and dental health are partly due to the mechanical action of the fibres and partly due to the pharmacological actions of the various chemical constituents contained therein. This is supported by the observations and research findings of various workers as outlined below:
1.Fluoride and Silicone
Chewing-sticks made from Diospyros, Gar-cinia and Gaultheria species have been found to be rich in fluoride and silicone (Kao and Li, 1968; Losee and Adkins, 1969). Fluoride has-been reported to exert anticariogenic action by (a) strengthening the apatite of teeth due to increased rate of maturation of the enamel surface (b) reducing enamel solubility, (c) favouring the formation of hydroxyl-apatite crystal structure during dissolution and remineralization of enamel, and (d) exerting an inhibitory effect on the growth of micro-organisms or their cariogenic potential by blocking their enzymes (Losee and Adkins, 1969; Peach, 1975). One of the chewing sticks, Diospyros tricolor, rich in fluoride, has been reported to reduce acid production without affecting the rate of growth of cariogenic bacteria (Elvin-Lewis et al., 1974). In addition to fluoride many of the chewing-sticks have been shown to contain silicone which also accounts for the low caries rate seen among the continuous users of such chewing-sticks (Farooqui and Strivastava, 1968).
Many chewing-sticks particularly those belonging to the family Rutaceae contain alkaloids. The alkaloids usually have a bitter taste and exert different types of actions on body tissues. The Fagara species, for example contain alkaloid atarine, which possesses bactericidal, trypanocidal and antimalarial actions (Irvine, 1961). Some other alkaloids are known to exert vasoconstrictor or vasodilator and even analgesic actions (Elvin-Lewis, 1980). All these properties may positively contribute towards dental welfare.
3. Essential Oils
Many chewing sticks such as Aegles marmelos, Aza-dirachta indica, Daniellia oliverae, Fagara zanthoxyloides, Gaultheria procumbens, Pogamia pinnata, Populus euphratica, Rhus cotinus and Zanthoxylum alatum contain essential (volatile) oils which possess characteristic aroma. Many of them exert carminative, anti-septic and analgesic actions. Some of these oils are applied locally on carious teeth, infiammed gums or mucous membranes to relieve pain (Lewis and Elvin-Lewis, 1977).
4. Tannins and Resins
Tannins exert astringent or somewhat irritant action on the mucous membranes. Similarly, resins also possess irritant and many other varied pharmacological properties. They form a coat over the enamel and thus protect against tooth decay. Some of the plants which are known to contain tannins and/or resins are Alchornea cordifolia, Cassia auriculata, Euclea multiflora Garcinia kola, Garcinia mangostana, fatropha curcas, funglans regia, parinari curatellifolia, Rhus curcas, Waltheria indica, and Zanthoylum alatum (Nadkarni, 1954; Lewis and Elvin-Lewis, 1977).
5.Anthraquinones and Related Compounds
Some of the chewing-sticks such as those made from Diospyros barteri, Acacia modesta, Acacia arabica are known to contain anthraquin-ones and/or related compounds (Nadkarni, 1954). These substances exert antibacterial, antidysen-teric and mild laxative effect in different doses. It is possible that continuous use of such chewing-sticks may, in addition to contributing towards oral hygiene, also improve appetite and regulate the peristaltic movements.
Some Pharmacological Properties of Chewing-sticks
1. Antibacterial Effect
Many studies have indicated that certain chewing-sticks possess antibacterial properties and can thus reduce the growth rate and production of acid in cultures of cariogenic bacteria (El-Said et al., 1971; Buadu and Boakye-Yiadom, 1973; Elvin-Lewis et al., 1974; Boakye-Yiadom and Konning, 1976; Manley et al., 1975). Diospyros loureiriana contains an antibiotic while some other type of antibacterial agents are present in plants such as Adina microcephala, Alchornea cordifolia, Azadirachta indica, Citrus aurantifolia, Diospyros bacteri, Fagara zanthoxy-loides, Garcinia kola, Mangifera indica, Mussaendra acuminata, Paullinia pinnata, Tamarindus indica, Vernonia amygdalina, Vitex simplicifolia, and Waltherai indica. The active ingredients in many of these plants have not yet been indentified or isolated. However, in Garcinia morella, broad spectrum activity has been associated with antibiotics Morellin and Gutifferin (Korzybski et al., 1967).
2. Anti-Inflammatory Effect on Gums
It is well known that inflammation of gums occurs quite often during tooth brushing. However, many of the chewing-sticks such as Alnus glutinosa, Antidesma venosum, Azadirachta indica, Dialium guineense, Glycosmia pentaphylla, Gouania lupuloides and Parinari curatellifolia contain substances which possess strong anti-inflammatory effect on gums.
3. Analgesic (Dental) Effect
Extracts of certain plants have been found to be effective in relieving toothache. Local analgesic AMD anaesthetic properties have been demonstrated in many species of the Acacia, Alchornea, Fagara and Zanthoxylum, which are, therefore, used in various preparations to alleviate toothache (Lewis and Elvin-Lewis, 1977). The active principles in many of these plants have not yet been isolated.
4. Anticarcinogenic and Antineoplastic Effect
The anticarcinogenic and antineoplastic activities have been shown in sticks from Dialium guiveense, Diospyros tricolor, Fagara zanthoxy-loides, Garcinia kola, Massularia acuminata and Rhus glabra. The widely used Diospyros species contain metabolites which exert antineoplastic effects (Thomas, 1971). Extract of Fagara macrophylla is scheduled for pharmacological trial in the cancer chemotherapeutic research programme of U.S. National Institute of Health. Thus, it is possible that regular use of such chewing-sticks may help in reducing the incidence of neoplasms especially in the oral cavity.
(The complete article is published in the journal of Pakistani Medical Association)