|Year : 2015 | Volume
| Issue : 1 | Page : 25-30
An ancient herb aloevera in dentistry: A review
Indavara Eregowda Neena1, Edagunji Ganesh2, Parameshwarappa Poornima1, Roopa Korishettar1
1 Department of Pedodontics and Preventive Dentistry, College of Dental Sciences, Davangere, Karnataka, India
2 Department of General Surgery, JJMMC, Davangere, Karnataka, India
|Date of Web Publication||7-Jul-2015|
Indavara Eregowda Neena
Department of Pedodontics and Preventive Dentistry, College of Dental Sciences, Pavilion Road, Davangere - 577 004, Karnataka
Source of Support: None, Conflict of Interest: None
The Egyptians called Aloe the "plant of immortality" because it can live and even bloom without soil. Aloe vera is well-known for its marvelous medicinal properties. These plants are one of the richest sources of health for human beings coming from nature. It has been grown as an ornamental plant widely. Products of the plant are used in the treatment of various ailments. A. vera is gaining popularity in dentistry as it is completely natural and there are no side effects being reported with its use. This paper gives an overview of the uses of this miracle plant and its uses in dentistry.
A. vera has been used in dentistry for its wound-healing effects, gingivitis, plaque control, and curing oral mucosal lesions. A. vera may also reduce the pain and duration of oral ulcers while speeding healing. The dentists should use A. vera at a level high enough to maximize its therapeutic benefit.
Keywords: Aloe vera, dentistry, gingivitis
|How to cite this article:|
Neena IE, Ganesh E, Poornima P, Korishettar R. An ancient herb aloevera in dentistry: A review. J Oral Res Rev 2015;7:25-30
|How to cite this URL:|
Neena IE, Ganesh E, Poornima P, Korishettar R. An ancient herb aloevera in dentistry: A review. J Oral Res Rev [serial online] 2015 [cited 2021 May 18];7:25-30. Available from: https://www.jorr.org/text.asp?2015/7/1/25/160174
| Introduction|| |
The Aloe vera plant has been known and used for centuries for its medicinal and skin care properties. The name A. vera derives from the Arabic word "Alloeh" meaning shining bitter substance while "vera0" in Latin means true. The Greek scientists regarded A. vera as the universal panacea.1 as anti-inflammatory, antiviral, antibacterial, and antioxidative effects are proven in A. vera, its use as an herbal remedy in dental conditions is increasing. 
Among the various currently available herbal agents, the most popular and currently receiving a lot of scientific attention is A. vera. It is a perennial succulent xerophyte, which develops water-storage tissue in the leaves to survive in dry areas of low or erratic rainfall.  The plant has stiff gray-green lance-shaped leaves containing clear gel in a central mucilaginous pulp. Benefits associated with A. vera have been attributed to the polysaccharides contained in the gel of the leaves. It is a cactus-like plant that grows in hot and dry climates. Numerous studies on A. vera are being done to demonstrate the antiviral, antibacterial, analgesic, anti-inflammatory, and wound healing properties. The Aloe barbadensis plant consists of two different parts, each of which produces substances with completely different compositions and therapeutic properties. The parenchymal tissue makes up the inner portion of the Aloe leaves and produces the A. vera gel (or mucilage), a clear, thin, tasteless, jelly-like material. This tissue is recovered from the leaf by separating the gel from the inner cellular debris. The other part of the plant is a group of specialized cells known as the pericyclic tubules, which occur just beneath the outer green ring of the leaf. These cells produce an exudate that consists of bitter yellow latex with powerful laxative-like actions. 
| History|| |
The plant A. vera has a history dating back to biblical times. A. vera has been used for medicinal purposes in several cultures for millennia: Greece, Egypt, India, Mexico, Japan, and China. Egyptian Queens Nefertiti and Cleopatra used it as part of their regular beauty regimes. Alexander the Great and Christopher Columbus used it to treat soldiers' wounds. The first reference to A. vera in English was a translation by John Goodyew in A.D. 1655 of Dioscorides' Medical treatise De Materia Medica. 
| Aloe Vera and Health Benefits|| |
A. vera, the miracle herb, is proven itself in being beneficial in many health functions. It is a source of 19 out of 20 essential amino acids which is required by our body, and these amino acids help in smooth functioning of our complex enzyme system. The next most useful benefit of A. vera is its source of vitamins, which includes A, B, C, E, and folic acid. As this plant grows in soil rich in minerals, it becomes a rich source of calcium, sodium, potassium, magnesium, iron, copper, and zinc. A. vera is also thought to be a good antiviral, antibacterial, and antifungal, as the inner gel is surrounded by polysaccharides which are able to defend our body from all these attacks. It is also proved to be an effective anti-inflammatory agent with analgesic properties. Studies have shown that the extracts of this gel have an inhibitory action on the arachidonic acid pathway via cyclooxygenase (COX) inhibiting inflammation. A. vera is proved to be beneficial in dermatological problems and helps in good skin tone by increasing the activity of fibroblasts. These fibroblasts produce collagen and elastic fibers and give the skin its structure. The moisturizing effect of A. vera due to polysaccharide components provides and sustains moisture in tissues. A large number of studies have shown the healing property of A. vera. It improved healing by increasing the blood supply, which increased oxygenation as a result. Davis et al., in his study examined the possibility of Aloe gel being an active growth substance as mannose-6-phosphate was the major sugar in Aloe gel. 
Different mechanisms have been proposed for the wound-healing effects of Aloe gel, which include keeping the wound moist, increasing epithelial cell migration, more rapid maturation of collagen, and reduction in inflammation. A 1996 study reported that a high molecular weight polypeptide constituent from the gel demonstrated a healing effect on excisional wounds in rats. Glucomannan, a mannose-rich polysaccharide, and gibberellin, a growth hormone, interact with growth factor receptor on the fibroblast, thereby stimulating its activity and proliferation, which in turn increases collagen synthesis after topical and oral application. Yagi et al. reported that A. vera gel contains a glycoprotein with cell proliferating-promoting activity, while Davis et al. noted that A. vera gel improved wound healing by increasing blood supply (angiogenesis), which increased oxygenation as a result. Angiogenesis is the growth of new blood capillaries and is a part of tissue regeneration. A 1993 study showed that topical application of A. vera gel reestablished vascularity of burn tissue for a guinea pig, although no specific constituents were identified. The A. vera gel polysaccharide acemannan was shown to activate macrophages, an effect that improved wound healing in a rat model. Two years later, Davis et al. reported that the low molecular weight component of freeze-dried A. vera gel stimulated blood vessel formation in a chick chorioallantoic membrane (i.e., a vascular membrane derived from developing chicken eggs); in addition, a methanol soluble fraction of the gel which contains a glycoprotein with mainly cell proliferating-promoting activity stimulated the proliferation of artery endothelial cells in an in vitro assay and induced them to invade a collagen substrate. Skin hydration effect: It was proposed that the A. vera gel formulations with higher concentrations (0.25% w/w and 0.5% w/w) improved skin hydration possibly by means of a humectant mechanism. Humectant mechanism means that the Aloe gel works by attracting water from the dermis below and by helping to keep this water bound in the stratum corneum.
Aloe has excellent anti-aging effect by producing the collagen and elastin fibers making the skin more elastic and less wrinkled as reported in an in vivo study conducted on mouse ears by Davis et al. One of the main reasons for this lies in the plant's unique ability to increase production of human fibroblast cells between 6 and 8 times faster than normal cell production. Fibroblast cells are found in the dermis of the skin and are responsible for the fabrication of collagen, the skin's support protein which keeps skin firm, supple, and youthful-looking. It was found that A. vera not only improved fibroblast cell structure but also accelerated the collagen production process.
It inhibits the CXO pathway and reduces prostaglandin E2. Recently, the novel anti-inflammatory compound called C-glucosyl chromone was isolated from gel extracts. In addition, the peptidase brady kinase was isolated from Aloe and shown to break down the bradykinin, an inflammatory substance that induces pain.
The activity of A. vera inner gel against both Gram- and Gram-negative bacteria has been demonstrated by several different methods. Streptococcus pyogenes and Streptococcus faecalis are two microorganisms that have been inhibited by A. vera gel. A. vera gel reportedly was bactericidal against Pseudomonas aeruginoa while acemannan prevented it from adhering to human lung epithelial cells in a monolayer culture.
A processed A. vera gel preparation reportedly inhibited the growth of Candida albicans.
This action may be direct and indirect: Indirect due to stimulation of immune system, and direct due to Aloe emodin. Aloe emodin in A. vera makes it so that certain viruses are not able to function. Therefore, A. vera is virucidal to herpes simplex virus type 1 and type 2, Varicella zoster virus, pseudorabies virus, and influenza virus according to the research of Thomson. During the course of these studies, it was found that the virucidal activity was due to the anthraquinones extracted from the inner leaf of Aloe and the roots, bark, or leaves of a number of other anthraquinone-containing plants. The results indicated that Aloe emodin directly affected both DNA- and RNA-containing enveloped viruses but had no effect on naked one.
A. vera , a great immune stimulant, contains 90% rhodium and iridium (trace minerals) in the acemannan which is one of the polysaccharides which dramatically increases the white blood cells or macrophages and T cells. Thus, immunomodulating effects occur via activation of macrophage cells to generate nitric oxide, secrete cytokines (e.g., tumor necrosis factor, interleukin-1, interleukin-6, and interferon-γ), and present cell surface markers. It helps enlarge the thymus gland in size by 40%. The thymus is what produces the T cells of the immune system.
A. vera has very strong antioxidant nutrients. Glutathione peroxide activity, superoxide dismutase enzymes, and a phenolic antioxidant were found to be present in A. vera gel, which may be responsible for these antioxidant effects. Apart from these, it also contains A, C, and E Vitamins. These free radical components get rid of the toxins and carcinogenic properties, we have in our bodies from the pollution and poor quality foods we eat. We acquire these free radicals in our bodies through absorption of our skin and digestion.
The two fractions from Aloes that are claimed to have anticancer effects include glycoproteins (lectins) and polysaccharides. Different studies indicated antitumor activity for A. vera gel in terms of reduced tumor burden, tumor shrinkage, tumor necrosis, and prolonged survival rates. An induction of glutathione S-transferase and an inhibition of the tumor-promoting effect of phorbol myristic acetate have also been reported which suggest Aloe gel in cancer chemoprevention. Indirect action on antitumor activity is stimulation of the immune response.
Anthraquinones increase intestine water content, stimulate water secretion, and increase intestinal peristalsis. And as mentioned earlier, a group of specialized cells known as the pericyclic tubules, which occurs just beneath the outer green ring of the leaf, produces an exudate that consists of a bitter yellow latex with powerful laxative-like actions. 
| Antioxidant Effects and Free Radical Scavenging Activity of Aloe vera|| |
Three relatively recent reports have demonstrated an antioxidant action for some constituents of A. vera gel. Three aloesin derivatives from Aloe (namely isorabaichromone, feruoylaloesin, and p-coumaroylaloesin) showed potent free radical and superoxide anion-scavenging activities in an assay using the lipid peroxidation rat liver microsomal system as the free radical generator. This lipid peroxidation assay is recognized as a standard technique for measuring the free radical scavenging effects of anti-oxidants. The same study noted that aloesin compounds inhibited COX-2 and thromboxane (Tx) A2 synthase; such actions could explain in part the healing effects of A. Vera. A subsequent study by Hu et al. used a similar assay system for free radicals to confirm the antioxidant action of A. vera extracts. This report also observed that the growth stage of A. Vera plays a significant part in the composition of antioxidant constituents and the antioxidant activity. Finally, a glycoprotein fraction from A. vera (14 kDa) showed a radical scavenging activity against superoxide anion, generated by a free radical generating system known as the xanthine-xanthine oxidase system; this fraction also inhibited COX-2 and reduced Tx A2 synthase levels in vitro. The authors of this study suggested that both specific glycoproteins and aloesin-related compounds played an important role in the anti-inflammatory activity of gel from A. vera leaves. 
| Mechanism of Action|| |
A. vera contains 75 potentially active constituents: Vitamins, enzymes, minerals, sugars, lignin, saponins, salicylic acids, and amino acids. It acts in many ways. A. vera is a potent anti-inflammatory agent; it inhibits the COX pathway and reduces prostaglandin E2 production from arachidonic acid. It is particularly known for its penetrating capacity to reach deeper layers of the dermis when applied topically. It has strong antiseptic properties being bactericidal, fungicidal, and virucidal. It promotes cell growth. It is neurologically calming and also acts as a detoxifying agent. A. vera has been shown to enhance defense mechanisms, and it has a variety of components to help combat periodontal disease and other oral conditions. 
| Aloe vera in Dentistry|| |
There are eight main uses of A. vera in dental practice:
- Periodontal surgery.
- Applications to the gum tissues when they have been traumatized or scratched by toothbrush-dentifrice abrasion, sharp foods, dental floss, and toothpick injuries.
- Chemical burns from accidents with aspirin.
- Extraction sockets.
- Acute mouth lesions such as herpetic viral lesions, aphthous ulcers, canker sores, and cracks occurring at the corners of our lips. Gum abscesses are soothed by the applications as well.
- Chronic oral diseases, Lichen planus and benign pemphigus, gum problems associated with AIDS and leukemia. Migratory glossitis, geographic tongue, and burning mouth syndrome.
- Denture patients with sore ridges and ill-fitting dentures and partials.
- Dental implants.
| Aloe vera in Endodontics|| |
A. vera has an antimicrobial effect against resistant microorganisms found in pulp space that is C. albicans and Enterococcus faecalis. Water, chloroform, and alcohol extracts of A. vera derived from pulp are found to have antibacterial efficacy and can be used as an intracanal medicament. Can be used in root canals as sedative dressing and as file lubricant. The nerve ends in a root canal are very sensitive. A. vera greatly helps to lessen its sensitivity. This gel can be placed inside the pulp chambers, while broaching to make Aloe work in the pulp canals; Aloe can also be used as canal lubricant. During closed dressings, cotton pellet with CMCP drops could be added with a drop of A. vera gel and then sealed with temporary restorations. Soothing healer to periodontal disease sub gingival administration of A. vera gel results in improvement of the periodontal condition and can be used as a local drug delivery system in periodontal pockets. Pockets when filled with gel up to gingival margins and Copake placed over it shows a reduction in pocket depth, gingival index, and plaque index. Gingival and periodontal diseases A. vera greatly reduces the instances of gum bleeding due to its soothing and healing properties, reduces swelling and soft tissue edema. Hence, stops bleeding and restores gums to health, reduces plaque and calculus formation. A. vera should be used as a mouthwash 1 tbsp. swish around the mouth and then swallow it 3 times a day.
| Halitosis|| |
A. vera is natural anti-fungal and antibacterial agent. It protects the sensitive tissue in the mouth, kills bacteria as well as fight tooth decay. Boosts body's ability to create collagen, which strengthens weak and swollen gums. Take a 1/4 cup of pure A. vera gel and dissolve it in about 1/2 cup of water or apple juice. Drink this to soothe acid indigestion, which is a very common cause of bad breath.
| Denture Care|| |
Smoothening A. vera gel onto the denture once or twice a day. A. vera has antifungal benefits, so prevents fungal infections. It prevents denture stomatitis. It can be used along with soft liners.
| Denture Adhesives|| |
It is sticky and viscous nature of gel. It strengthens gums, soothes, and alleviates gum irritation like gum sores (ulcer). It has adequate adhesive strength to wet and dry conditions.
| Aloe vera as a Tooth Gel|| |
It cleanses and soothes teeth and gums and effective in fighting cavities. Anthraquinones help in healing and arresting pain. Less harsh on teeth as it does not have the abrasive elements and hence is a better alternative for people with sensitive teeth or gums. A study by Stanford University revealed that A. vera tooth gel is equivalent, and at times more effective, than the commercial brands, in controlling cavity-causing organisms.
| Aloe vera as a Mouthwash|| |
Mouthwash prevents radiation-induced mucositis by its wound healing and anti-inflammatory mechanism. It reduces oral candidiasis of patients undergoing head and neck radiotherapy due to its antifungal and immunomodulatory properties. Effective substitute for TA in the treatment of oral Lichen planus 1-3 tablespoon of A. vera juice to be used as a mouthwash, then swallowed three times daily.
| Dental Implants|| |
A. vera gel placed around dental implants is found effective to reduce inflammation. A. vera reduces inflammation by its antimicrobial and anti-inflammatory effects, active components with its properties: A. vera contains 75 potentially active constituents: Vitamins, enzymes, minerals, sugars, lignin, saponins, salicylic acids, and amino acids.
| Mechanism of Actions|| |
Glucomannan, a mannose-rich polysaccharide, and gibberellin, a growth hormone, interacts with growth factor receptors on the fibroblast, thereby stimulating its activity and proliferation, which in turn significantly increases collagen synthesis after topical and oral A. vera.
Effects on skin exposure to ultraviolet and gamma radiation
A. vera gel has been reported to have a protective effect against radiation damage to the skin. Exact role is not known, but following the administration of A. vera gel, an antioxidant protein, metallothionein, is generated in the skin, which scavenges hydroxyl radicals and prevents suppression of superoxide dismutase and glutathione peroxidase in the skin.
A. vera inhibits the COX pathway and reduces prostaglandin E2 production from arachidonic acid.
Effects on the immune system
Alprogen inhibits calcium influx into mast cells, thereby inhibiting the antigen-antibody-mediated release of histamine and leukotriene from mast cells.
Anthraquinones present in latex are a potent laxative. It increases intestinal water content, stimulates mucus secretion, and increases intestinal peristalsis.
Antiviral and antitumor activity
These actions may be due to indirect or direct effects. The indirect effect is due to stimulation of the immune system, and direct effect is due to anthraquinones. The anthraquinone aloin inactivates various enveloped viruses such as herpes simplex, varicella zoster, and influenza.
Moisturizing and anti-aging effect
Mucopolysaccharides help in binding moisture to the skin. Aloe stimulates fibroblast which produces the collagen and elastin fibers making the skin more elastic and less wrinkled. It also has cohesive effects on the superficial flaking epidermal cells by sticking them together, which softens the skin.
A. vera contains antiseptic agents: Lupeol, salicylic acid, urea nitrogen, cinnamic acid, phenols, and sulfur. They all have inhibitory action on fungi, bacteria, and virus.
| Side Effects|| |
It may cause redness, burning, stinging sensation, and rarely generalized dermatitis in sensitive individuals. Allergic reactions are mostly due to anthraquinones, such as aloin and barbaloin. It is best to apply it to a small area first to test for possible allergic reaction.
Abdominal cramps, diarrhea, red urine, hepatitis, dependency or worsening of constipation. Prolonged use has been reported to increase the risk of colorectal cancer. The laxative effect may cause electrolyte imbalances (low potassium levels).
Application of Aloe to the skin may increase the absorption of steroid creams like hydrocortisone. It reduces the effectiveness and may increase the adverse effects of digoxin and digitoxin, due to its potassium lowering effect. Combined use of A. vera and furosemide may increase the risk of potassium depletion. It decreases the blood sugar levels and thus may interact with oral hypoglycemic drugs and insulin. Thus, though A. vera has a wide spectrum of the properties and uses, some of them could be myths and some of them could be real magic. In future, controlled studies are required to prove the effectiveness of A. vera under various conditions. 
A. vera is available and used as:
- Toothpaste: Can be used by all patients, safe during pregnancy.
- Jelly: Used for skin infections/lesions-like acne, eczema, psoriasis, generalized itching.
- Hand cream: Used for counteracting frequent hand wash and itching due to wearing of latex gloves.
- Oral spray: For throat infections, painful eruption of wisdom teeth.
- Juice: For correcting irritable bowel syndrome, joint and skin lesion like arthritis, rheumatism (along with topical application of gel), as a routine general tonic, powerful nutritional supplement and antioxidant, used for peptic ulcers, acid reflux, Crohn's disease, candida, etc.
| Toxicity|| |
Ingestion of A. vera is sometimes associated with diarrhea, electrolyte imbalance, kidney dysfunction and conventional drug interactions; episodes of contact dermatitis, erythema, and phototoxicity have been reported from topical application. The diarrhea caused by the laxative effect of A. vera can decrease the absorption of other systemically used drugs. However, these side effects are not seen in all patients. It is hence, important to choose an Aloe product which is pure, stabilized, concentrated, and grown organically. Furthermore, it is desirable to check for the label of accreditation "Seal of Approval of The International Aloe Science Council" as this seal guarantees the desired necessities. 
| Contraindications|| |
Side-effects may be categorized into topical and systemic routes as follow.
| Topical|| |
Redness, burning, and stinging sensation. Allergic reactions are mostly due to anthraquinones, such as aloin and barbalion. It is best to apply it on a small area first to test for possible reaction.
| Systemic|| |
Abdominal cramps, diarrhea, red urine, hepatitis, dependency of worsening of constipation. Prolonged use has been reported to increase the risk of colorectal cancer. The laxative effect may cause electrolyte imbalances (low potassium levels). 
| Conclusion|| |
A. vera may find a promising role in various branches of dentistry in future. Proper diagnosis, knowledge of the traditional medicine, and implementation of that knowledge to the treatment plan are important in ensuring success with this dental therapeutic agent. A. vera has a lot to offer in the field of dentistry, a lot of studies are on the way to utilize the effective antimicrobial property of the miracle plant. Interest is gathering for the use of A. vera in dentistry, and this natural therapy is already proved its unlimited use in our field. Standardization and quality assurance of A. vera products play a key area which needs to be focused. A. vera, a promising herb with its various clinical applications in dentistry, more clinical research should be undertaken and hence that it can establish itself in this field and mankind can be benefitted with its wide range of properties. 
Financial support and sponsorship
Conflict of interest
There are no conflicts of interest.
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