|Year : 2022 | Volume
| Issue : 3 | Page : 57-61
Propolis: A natural remedy to clinical problems in pediatric dentistry
Sanhati Biswas, K Premkishore
Department of Pediatric and Preventive Dentistry, Rungta College of Dental Sciences and Research, Bhilai, Chhattisgarh, India
|Date of Submission||10-Feb-2022|
|Date of Decision||25-Mar-2022|
|Date of Acceptance||26-Mar-2022|
|Date of Web Publication||20-Jun-2022|
House No. 43, Shyamange, Lokenath Nagar, Bagdogra, Darjeeling - 734 014, West Bengal
Source of Support: None, Conflict of Interest: None
Physiology of a child is much different from an adult and a child should not be considered a small-sized adult. They have different developmental pharmacokinetics due to which they are more sensitive to drug effects. This has led to the adoption of new dental materials derived from natural origin instead of conventional chemicals to reduce the side effects and complications. Propolis is one such natural substance that is widely used for various clinical trials in dentistry and has shown very promising results. Due to its anti-inflammatory, anticariogenic, and immunomodulating effects, it has now become quite familiar material in dental applications. It is eco-friendly, economical, complications free, easily available, and easy to use in daily dental practices. Hence, it has opened a new field of research and analysis for scientists and researchers.
Keywords: Dental implication, green dentistry, propolis
|How to cite this article:|
Biswas S, Premkishore K. Propolis: A natural remedy to clinical problems in pediatric dentistry. J Prim Care Dent Oral Health 2022;3:57-61
|How to cite this URL:|
Biswas S, Premkishore K. Propolis: A natural remedy to clinical problems in pediatric dentistry. J Prim Care Dent Oral Health [serial online] 2022 [cited 2022 Oct 1];3:57-61. Available from: http://www.jpcdoh.org/text.asp?2022/3/3/57/347800
| Introduction|| |
The most important aspect of pediatric dentistry is to preserve the primary teeth until its natural exfoliation as it acts as a natural space maintainer in a child's oral cavity until the eruption of permanent teeth. Deciduous teeth facilitate mastication, guides phonetics, proper growth of jaws, and esthetic requirements of the child during the growth period. The most common cause of early exfoliation of deciduous teeth is pulp necrosis. Pulp therapy in children is not easy due to the complex anatomy of deciduous teeth. Another thing to keep in mind during the treatment of the pediatric age group is that they are more sensitive to drug formulations as there is a difference in developmental pharmacokinetics. They have increased brain/body weight ratio and higher blood–brain barrier permeability along with more body water versus lipid in early life and difference in serum protein composition. To reduce the side effects of these drugs, the modern era of medical science is shifting to more natural methods with a motto of “Green Dentistry.” The recent advancements in this field include the use of natural products instead of allopathic or synthetic antibiotics to overcome the antibiotic resistance of some bacterial strains.
Propolis is one such natural substance that is widely used for various clinical trials in dentistry, and the results are very promising. Propolis or bee glue is a resinous mixture that honey bees produce by mixing saliva and beeswax with exudate gathered from tree buds, sap flows, or other botanical sources. Propolis has waxy nature and mechanical properties which is used by bees to construct and repair their hive for sealing openings and cracks and smoothing out the internal walls. Honey and beeswax have been used as medicines since ancient times. It was used as a healing product for mucocutaneous wounds by Romans. It has been listed as an official drug in the 17th century due to its antibacterial activity in the London pharmacopoeias. Propolis has various therapeutic effects including anti-inflammatory, antifungal, antiprotozoal, and antioxidant activity. Strains such as Actinomyces naeslundii, Porphyromonas gingivalis, Fusobacterium nucleatum, Veillonella parvula, Lactobacillus acidophilus, Peptostreptococcus anaerobius, Peptostreptococcus micros, Prevotella oralis, and Prevotella melaninogenica showed inhibition in growth due to ethanolic propolis. Nowadays, there is has shown to increase the prevention of gingivitis and microbial infections.
| Characteristics of Propolis|| |
Propolis is lipophilic in nature. It contains around 50% resins, 30% waxes, 10% essential oils, 5% pollen, and 5% of various organic compounds. However, the chemical composition and physiological properties of raw propolis depend on the geographical factors of the area such as climate, temperature, and source. Its lipophilic nature makes it easily soluble in various types of solvents for use in therapeutic purposes. The physical form of propolis changes with temperature. It ranges from hard to brittle at freezing temperature, soft at 20°C–30°C to sticky, and gummy at temperature <45°. It becomes liquid at the temperature of 60°C–70°C, but for some samples, the melting point may be as high as 100°C. Therapeutic uses of propolis is summarised in [Table 1].
| Therapeutic Uses of Propolis in Pediatric Dentistry|| |
Endodontic therapy of primary teeth
The purpose of endodontic treatment of deciduous teeth is the removal of infected and necrosed pulp tissue along with the elimination of contamination by pathogenic bacteria without irritating the periapical tissues.
Intracanal medicament and root canal irrigant
Intracanal medicaments reduce inflammation and act as an analgesic along with disinfecting the root canal system and preventing resorption of root and periradicular bone.
In an in vitro study, performed by Guven Kayaoglu et al. on extracted tooth to check the efficacy of propolis on intracanal bacteria compared to the convectional intracanal medicament like calcium hydroxide (CaOH2), propolis has shown promising results in the elimination of Gram-positive facultative anaerobe Enterococcus faecalis. The antibacterial effect of propolis on dentinal tubules was found to be as same as CaOH2 and chlorhexidine (CHX).
Another study conducted by Rouhani A et al. suggested that propolis and CaOH2 have similar physical properties as an intracanal medication, but the toxic effects of propolis on periodontal ligament (PDL) fibroblasts and dental pulp are 10 times less than the CaOH2 and can be more easily removed from the canals than CaOH2.
In a study to check the biochemical and radiographic assessment of propolis in pulpectomy, it was concluded that the clinical and radiographic success was mainly attributed to the antioxidant activity of propolis and to a lesser extent to its antibacterial properties. Ethanolic extract of propolis (EEP) exhibited activity against Staphylococcus aureus and Pseudomonas aeruginosa. The study concluded that propolis is a natural and economical alternative when it is used as an irrigator in pulpal therapy (pulpectomy) in pediatric patients. The bactericidal activity of Yucamiel propolis was found positive only against S. aureus and P. aeruginosa, at 20% concentration.
A number of studies over the years have suggested the anti-inflammatory effect of propolis. Bachiega et al. concluded that cinnamic acid and coumaric acid in propolis impede interleukin (IL)-6 and IL-10 but encourage IL-B production by macrophages.
Edara Lillygrace et al. conducted a study comparing the antimicrobial efficacy of triple antibiotic paste and propolis as an intracanal medicament in young permanent teeth, and the results suggested that propolis as intracanal medicament had a similar efficacy in reducing the microbes compared with triple antibiotic paste. They concluded that in young permanent dentition with an open apex, propolis can be used as an intracanal medicament.
Propolis has been found to be an effective irrigating solution for deciduous teeth. It has been observed in a study comparing the effect of saline and propolis on root canal pathogens. The comparison of the mean change (pre-post) of streptococci and Staphylococcus bacterial colony counts in two groups showed a significant difference and higher decrease in streptococci and Staphylococcus colony and E. faecalis and Escherichia coli count in propolis as compared with normal saline.
In order to maintain the pulp vitality of the deciduous teeth when the caries is about to reach the coronal pulp one of the most common procedures that is carried out in children is pulpotomy. It creates a tissue barrier beneath the medicament and preserves the vitality of the pulp. In a randomized, clinical study conducted by Beltagy and Ghoname on primary molars, the success rate of pulpotomized teeth with propolis extract was found 94.12% and 88.24% for formocresol group at the end of the study. Propolis extract-treated teeth were clinically symptom free at 3 and 6 months. After follow-up of 12 months, one case presented with pain related to one tooth treated with propolis extract and another one showed pathological mobility in formocresol group. Histological examination of the propolis-treated teeth revealed mild chronic inflammation, initial calcification, irregular odontoblastic layer, and hyperemic blood vessels after 1 month. Increased intrapulpal calcifications with incomplete dentinal bridges formation and regular odontoblastic layer were evident after 3 months of propolis extract pulpotomy. There was degeneration of odontoblastic layer and no hard tissue formation and hyperaemic pulp in teeth with formocresol pulpotomy. After 3 months, liquefaction necrosis and pulp microabscess formation was evident in formocresol-treated teeth. Propolis extract-based paste is a promising pulpotomy agent.
Direct pulp capping
To preserve the vitality of a traumatized tooth, pulp capping is one of the best choices to prevent the pulp from further bacterial attack. The anterior teeth of children are more prone to fracture due to trauma. Hence, a biocompatible substance is used to initiate the dentin bridge and seal the pulp complex and maintain the vitality.
CaOH2 is considered the gold standard for pulp capping. But with newer advancements, the use of propolis as a pulp-capping agent has been popular these days. A study was conducted on 47 primary molars and 42 young permanent teeth of children aged 5–8 years to check the efficacy of propolis as pulp-capping agent. Teeth with pulp exposure of 1 mm2 were treated with Syrian crude propolis. After restoration, clinical and radiographical evaluations were performed at 1-, 6-, and 12-month intervals. After follow-up of 1 year, the success rate was 87.23%. In case of young permanent molars, all teeth were considered successful cases with a success rate of 100%.
In another study performed on 28 wistar rat tooth to check the effect of propolis on reparative dentin formation four rat groups were studied. One group was treated with only CaOH2 for 7 days and the second group – a combination of CaOH2 and propolis for 7 days. The group treated with a combination of propolis and CaOH2 for 7 days showed increased expression of IL-10, IL-8, toll-like receptor 2 (TLR-2), vascular endothelial growth factor (VEGF), and transforming growth factor-β (TGF-β) as compared to the group treated with only Ca (OH) 2. The expression of IL-10, TLR-2, TGF-β, and VEGF increased in the treatment group treated with propolis and Ca (OH) 2 for 14 days, while the expression of IL-8 decreased significantly.
Propolis contains flavonoids, phenolics, and other various aromatic compounds. Flavonoids and caffeic acid reduce the inflammatory response by inhibiting lipoxygenase pathway of arachidonic acid. Thus, the results from various studies suggest that propolis can act as an effective pulp-capping agent instead of CaOH2.
Children are not much able to maintain their oral hygiene as a result of that they are more susceptible to plaque accumulation and gingival problems. The use of mouthrinses containing CHX is very popular, and in the pediatric population, it has helped to overcome the gingival problems.
To investigate the effectiveness of propolis against plaque-forming microorganisms, a study was conducted comparing three mouthwashes containing saline as placebo group, second group with CHX, and third group with propolis. Plaque index at baseline and gingival index at baseline were noted after 5-day intervals. The results suggested that propolis has similar effectiveness as saline and is marginally equal to the effectiveness of CHX. Hence, it is a good alternative to chemicals such as CHX.
Another study was conducted using four different mouthrinse containing propolis solutions and mouthrinse containing 0.2% CHX on oral microorganisms and human gingival fibroblasts. In this study, different propolis solutions were used at 10%, 5%, 2.5%, and 1% concentrations. Cultures of fibroblasts were established from gingival biopsies obtained from healthy individuals. Cells used for the experiments proliferated in logarithmic phase between the 7th and 12th passages. The effectiveness of mouthrinse containing propolis samples on oral microorganisms was less than CHX. On the other aspect, propolis samples were found less cytotoxic on human gingival fibroblasts compared to CHX. Thus, propolis can serve as a good antiplaque agent.
It is a well-known fact that “Prevention is better than cure.” Hence, another aspect of pediatric dentistry is to prevent the caries attack on the deciduous teeth at very early stages of a child's dentition. Dental caries is mainly caused by Streptococcus mutans and lactobacillus. The main mechanism of caries occurrence is the fermentation of sugars into organic acids which leads to the demineralization of enamel. Bacteria attach itself to the tooth surface using “glucans” synthesized by S. mutans using glucosyltransferase. This further leads to the progress of caries toward pulp and leads to pain and discomfort during eating.
In a study, the antibacterial effect of propolis was tested on S. mutans count in the oral cavity of children. Saliva was collected before rinsing and after rinsing with diluted propolis solution. The results showed a significant difference in the number of S. mutans between collections on bacterial growth both after the beginning and at the end of treatment. These results showed a reduction in the number of S. mutans. Hence, propolis can be used as a natural substitute for the prevention of S. mutans growth in the oral cavity. Propolis showed a good cariostatic action based on this study.
In another study, cariostatic effect of propolis was compared with xylitol, a sugar substitute. In this study, 30 children of age 8–11 years were enrolled with decayed, missed, and filled teeth index <3. Saliva samples were collected before stimulation and then again collected at 15 min and after 1 h of chewing the two varieties of chewing gums.The amount of S. mutans in saliva was evaluated and the acceptance of the two chewing gums among the children was tested with a questionnaire. Propolis gum showed a statistically significant reduction in the number of colonies as compared to xylitol, and xylitol gum was more accepted than propolis gum by the children.
Storage media for avulsed tooth
Children are more prone to accidents and injury to their jaws due to their nature of playful mood, exploring nature, and less balance. Hence, the most common injury associated with these age groups is avulsion and fracture of the maxillary anterior tooth. Importance should be given to the storage media for the tooth and the extra-alveolar timing before its replantation as they play a significant role in preserving the viability of the periodontal ligament cells.
In vitro experimental study was done comparing the cell survival rates of PDL in propolis 50%, propolis 10%, Hanks' balanced salt solution (HBSS), milk, and egg white for different time points. A total of 60 periodontal disease-free anterior single-root teeth were extracted and used for the study. Save-A-Tooth solution marketed in the USA was used as a control group for the study. Each group was evaluated at 1 and 3 h after immersion. Trypan blue was used to determine the cell viability. Cells that took up trypan blue were considered nonviable. Propolis 10% showed more viability of PDL cells as compared to propolis 50%, egg white, milk, and HBSS solution.
In another study, histologic and histometric analysis was done on the influence of propolis 15%, and the fluoride solution was used as root surface treatment on the healing process after delayed tooth replantation. The upper right incisors were extracted from Wistar (Rattus norvegicus albinus) rats. The teeth were divided into three experimental groups: Groups I, II, and III of physiologic saline, 2% acidulated phosphate sodium fluoride, and 15% propolis, respectively, and then replanted. The animals were sacrificed after 60 days of replantation. Teeth treated with physiologic saline showed more inflammatory root resorption compared with those treated with fluoride or propolis. Therefore, propolis can act as a good alternative storage medium for avulsed teeth.
For orthodontic and esthetic corrections in children, there is a need of osseous extension of maxilla and premaxilla. Human skeletal system consists of a connective tissue network which supports bone modeling and remodeling during the initial growth period of a child. A lot of endogenous and exogenous factors are responsible behind this process of bone remodeling. Propolis could inhibit the synthesis of prostaglandin and the inducible cyclooxygenase-2 expression which explains its anti-inflammatory behavior.
An experimental study was done on 36 male rats to determine the bone-healing capacity of the propolis extract where a critical-sized, nonunion, radial bone defect model was repaired in rats, using chitosan and demineralized bone matrix (DBM) scaffolds along with propolis extract. The first two groups with the bone defects were left empty. The rest four groups were of the chitosan, DBM, chitosan-propolis, and DBM propolis. The scaffolds were injected with 0.1 ml of the diluted propolis extract (250 mg/ml) in the chitosan-propolis and DBM-propolis groups. After 56 days of experiment, the healing of radius and ulna complex was evaluated macroscopically. Radiographic evaluation showed significantly better results in the DBM-propolis than in the chitosan-propolis-treated group. Histopathologic evaluation showed that the autografted regions and bone edges were filled with woven bone and hyaline cartilage. DBM-propolis performance in the aspect of biomechanical performance was better as compared to the chitosan-propolis group. Hence, the potential role of DBM-propolis is to improve bone healing and acts as an effective combination in bone tissue engineering.
With the advancements in medical technology for cancer prevention and treatment, there are a lot of studies that are focused on the use of natural agents as anticancer agents. Propolis has been under various researches for some of its chemical components' anticancer effects. It has shown antitumor activity due to the presence of polyphenols. Studies have found that methylated phenols present in propolis prevented the proliferation of human squamous cell carcinoma by suppressing the anti-apoptotic proteins.
In a study effect of propolis extract from Indian stingless bee was tested against namely, MCF-7 (human breast cancer), HT-29 (human colon adenocarcinoma), Caco-2 (human epithelial colorectal adenocarcinoma), and B16F1 (murine melanoma), at different concentrations. Anticancer activity of the EEP was explored by testing the cytotoxic and apoptotic effects on the cancer cells. Cytotoxicity of EEP in four different cell lines (B16F1, MCF-7, HT-29, and Caco-2) was determined by MTT assay and trypan blue dye exclusion assay. EEP expressed a concentration and time-dependent cytotoxic effect. Determination of apoptosis was done by differential staining (ethidium bromide/acridine orange) and TUNEL (deoxynucleotidyl transferase-dUTP nick end labeling) assay. After 24 h, all the cell lines after treatment with 250 μg/mL EEP showed apoptosis. Thus, propolis is fatal for cancer-causing cells though more studies are required for pro-apoptotic activity of EEP.
Allergies related to propolis
Some subjects and patients give evidence of allergic reaction with propolis in case of contact chelitis contact stomatitis, perioral eczema, labial edema, oral pain, peeling of the lips, and dyspnea.,,
| Conclusion|| |
A lot of studies have been done and a lot are still ongoing to study the beneficial effects of this natural propolis. However, more clinical evidences are required for the successful and effective use of propolis as a natural alternative to conventional dental materials in pediatric dentistry. This can only be achieved by cooperation and combined efforts and studies of pharmaceutical science field, pharmacological studies, and dentists.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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