|
 
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| REVIEW ARTICLE |
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| Year : 2016 | Volume
: 8
| Issue : 2 | Page : 86-91 |
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Applications of ozone therapy in dentistry
Shiva Gupta, D Deepa
Department of Periodontology, Subharti Dental College and Hospital, Meerut, Uttar Pradesh, India
| Date of Web Publication | 13-Oct-2016 |
Correspondence Address:
D Deepa
Department of Periodontology, Subharti Dental College and Hospital, Meerut - 250 005, Uttar Pradesh
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/2249-4987.192243
Ozone is an allotropic form of oxygen, which is effectively used in the treatment of different diseases for more than 100 years. In the present era of increasing antibiotic resistance, ozone therapy is an alternative medical treatment that rationales to increase the amount of oxygen to the body through institution of ozone into the body. Owing to its beneficial biological properties including antimicrobial and immune-stimulating effects, ozone therapy has opened new vistas in treatment modalities of dental pathologies for patients of all ages. The objective of this article is to review the literature available on applications of ozone in dentistry. Keywords: Antimicrobial, dentistry, HealOzone, Nano bubble water (NBW3), ozone, ozone intoxication
How to cite this article:
Gupta S, Deepa D. Applications of ozone therapy in dentistry. J Oral Res Rev 2016;8:86-91 |
| Introduction | |  |
Ozone (O 3 ) is also known as trioxygen or triatomic oxygen, a higher energetic form of atmospheric oxygen (O 2 ) which consists of 3 atoms of oxygen. It is derived from the Greek word "Ozein" which means odorant. It has a defensive role in the earth's ecological harmony as it occurs naturally in the atmosphere and surrounds the earth at an altitude between 50,000 and 100,000 feet. [1] In the stratosphere when an oxygen molecule is stroked by high energy ultraviolet (UV) radiation, it splits into two free oxygen atoms, further these free oxygen atoms collide with oxygen molecules leading to the production of ozone. It is often created by thunder and lightning and is also known for its interaction with industrial pollutants at ground level.
Ozone is a blue gas present in abundance in stratosphere with a concentration of 16-20 mg/m. It swiftly gives up nascent oxygen molecule to form oxygen gas, hence considered as an unstable gas. Due to this instability, it has the highest oxidation potential, approximately 150% greater than that of chlorine when used as an antimicrobial agent. This strong oxidant property has led to use of ozone in medical and dental fields. Periodontitis is a chronic inflammatory disease of the supporting tissues of the teeth caused by specific microorganisms or group of specific microorganisms resulting in progressive destruction of periodontal ligament and alveolar bone with pocket formation, recession, or both. [2],[3] Ozone has found to be effective against Gram-positive and Gram-negative bacteria, fungi, and viruses. [4] The concentration of ozone varies between 1 and 100 μg/ml (0.05%-5%). The objective of this article is to summarize literature available on applications of ozone in dentistry.
| Historical Background | | |
German chemist Christian Friedrich Schonbein, of University of Basel in Switzerland was the first to discover ozone in 1840. The first ozone generator was developed by Werner Von Siemens (1857) in Germany and was first applied in medical field by Dr. C. Lender in 1870 to purify blood in test tubes. The scientific community did not study ozone seriously until 1936 when Dr. Fish, [5] a Swiss dentist used ozone either as gas or ozonated water in his practice. The lack of ozone resistant materials such as Dacron, nylon, and Teflon was the cause of restrictions and hitches of ozone therapy, until 1950 when manufacturing of ozone resistant material began. The first ozone generator for medical use was developed by Joachim Hδnsler, a German physicist and Hans Wolff, a German physician in 1957. However, it was only at the end of 1980s, medical ozone became a subject of dental research and practice. Subsequent to this, it was used increasingly for medical and dental purposes.
Medical grade ozone is a mixture of pure oxygen (95%-99.95%) and pure ozone (0.05%-5%). Due to its instability, it is impossible to store ozone over long periods, as within less than an hour after preparation only half of the mixture remains as ozone while the other half is transformed into oxygen. Therefore, it must be prepared immediately before use although association of O 3 with a vehicle with aqueous properties or viscous properties promotes or retards the conversion into oxygen.
Goals of ozone therapy [4] include (i) inactivates and eliminates pathogens, (ii) stimulation of immune system and improves circulation, (iii) reduction of inflammation and pain, (iv) stimulates humoral anti-oxidant system, (v) restore proper oxygen metabolism, (vi) prevention of shock and stroke damage, (vii) induce friendly ecological environment, (viii) improvement in brain function and memory.
| Ozone Generating Systems | | |
The three ozone generating systems are: [6]
- UV system: This system emits UV light at 185 nm producing low concentrations of ozone. An oxygen molecule absorbs light energy in ground state when exposed to UV light and then it dissociates. Later, the oxygen atoms react with other oxygen molecules to form ozone
- Cold plasma system: In this system, an electrostatic field is formed as the voltage jumps between the anode and the cathode rods. Air and water purification are applications of this system
- Corona discharge system: This system generates high concentration of ozone as a direct result of power dissipation. Ozone is formed through an electrical discharge that is diffused over an area using a dielectric to create a corona discharge. Oxygen passed through this corona discharge is converted into ozone. The handling of this design is easy and the ozone production rate can be controlled, hence most commonly used in the medical and dental fields.
| Applications of Ozone in Dentistry | | |
Ozone is a very good alternative and/or an additional disinfectant to standard antiseptics due to its undisputed disinfection power over other antiseptics.
According to Krammer, [7] a German dentist, aqueous ozone can be used:
- As a powerful disinfectant
- To control bleeding
- To cleanse wounds in bones and soft tissues
- To improve healing by increasing the local supply of oxygen to the wound area
- To increase the metabolic processes related to wound healing as ozonated water can increase the temperature in the wound area.
Ozonated water may be used as a mouth rinse in cases of gingivitis, oral thrush or stomatitis, as a spray to cleanse the affected area and todisinfect oral mucosa, as a water jet in treatment of painful gingivitis and stomatitis.
- Diagnostics - vitality test
- Prosthodontics and Restorative dentistry-crown disinfection, cavity disinfection
- Dental diseases - caries, enamel cracks, root canal treatment, tooth whitening, dentinal hypersensitivity, abscess, granuloma, fistulae, aphthae, Herpes infection, stomatitis - candidiasis
- Surgery - implantation, replantation, extraction, wound healing, coagulopathy-prolonged bleeding
- Orthodontics and Orthopedics - temporomandibular joint dysfunctions, trismus, relaxation, myoarthopathy.
Mechanism of action
- Antimicrobial action: [Table 1] [8]
- Ozone leads to destruction of bacteria, fungi, and viruses
- The mechanism of action includes firstly the damage to the cytoplasmic membrane of cells as a consequence to ozonolysis of dual bonds and secondly modification of intracellular contents because of secondary oxidant effect that leads to oxidation of protein loss of organelle function
- Due to the antioxidative ability the human body cells are not damaged and the action remains non-specific and selective to microbial cells
- All vital functions of bacteria (incapable of developing any self-immunity) are stopped as a result of few-seconds-application of ozone
- Gram-positive bacteria are more sensitive to the action of ozone than Gram-negative bacteria.
- Immunostimulating effect: [8],[9]
- The immunocompetent cell proliferation and immunoglobulin synthesis is stimulated as an influence of ozone to cellular and humoral immune system
- The function of macrophages is activated due to which sensitivity of microorganisms to phagocytosis is increased
- This further leads to production of cytokines as a consequence other immune cells are activated
- Biologically active substances such as interleukins, prostaglandins, and leukotrienes, which helpin reduction of inflammation and wound healing are synthesized by ozone
- Anti-hypoxic effect: [9]
- Ozone results in change of cellular metabolism by raising partial pressure of oxygen in tissues and improving the transportation of oxygen in blood
- Certain enzymes such as dehydrogenase, superoxide dismutases, glutathione peroxidases and catalases are activated by repetitive low doses of ozone
- Biosynthetic effect
- Ozone causes activation of protein synthesis mechanism with increased amount of mitochondria and ribosomes in cells that leads to elevation of functional activity and regeneration potential of tissues and organs. [9]
- Vasodilators (nitric oxide) that are responsible for dilatation of arterioles and venules are secreted by ozone. [9]
- Ozone intensifies remineralization potential when acting on the organic substance of mineralized tooth tissues.
- Also enables the diffusion of calcium and phosphorus ions to the deeper layers of carious cavities by opening of the dentinal tubules. [10]
| Routes of Ozone Administration | | |
Gaseous form
Gaseous ozone could be administered topically either by an open system or by a sealing suction system to avoid inhalation and adverse effects. Most frequently used in restorative dentistry and endodontics. It is a noninvasive therapy for treatment of dental caries and may be used as a disinfectant before the placement of a direct restoration and also as therapy for hypomineralized teeth. [11]
Ozonated water
It has been shown to be efficacious against Gram-positive and Gram-negative oral microorganisms as well as bacteria in plaque biofilm. In comparison to other chemical cleaners, it appears to be less expensive. [12] Gaseous ozone may be used as a dental disinfectant if applied for 3 min and is considered more effective microbicide than the aqueous form. [13] If ozone gas is inhaled into the respiratory tract [14] it has toxic effects, hence to control oral infections and various pathogensozonated water may be useful. [15] Commercially available as ultra-pure, tripple ozone treatment system.
Ozonized oil
It is competitive antimicrobial agent due to wide accessibility of sunflower oil. It is found efficacious against Streptococci, Enterococci, Staphylococci, Pseudomonas, Escherichia More Details coli and especially Mycobacteria and is used for the cure of fungal infections. [16] Commercially available as Oleozone, Bioperoxoil.
| Other Applications | | |
HealOzone by KaVo
It is an air-based system in which gas is applied in a closed circuit. Its surplus is sucked out and manganese ions neutralize it. The concentration of ozone is 2100 ppm in the cap adjacent to the tissue. Perfect air tightness of the cap is the necessity for the application of ozone. The cost ranges between Rs. 60,000 and Rs. 65,000.
OzonyTron by MYMED
The power of high frequency and voltage is used by this appliance. With the current strength, adjustment of ozone concentration could be done in 5 levels. A double glass camera forms the glass probe which consists of mixture of noble gases which conducts and emits electromagnetic energy. Energy is emitted around the treated area as the tip of the probe gets in contact with the body that causes splitting of environmental diatomic oxygen in singular atomic oxygen and ozone. Ozone concentration in the operation field is 10-100 μg/ml. Therefore, ozone could be applied to the areas that are difficult to reach and inaccessible such as gingival pockets or root canals, as there is no closed circuit here. The cost ranges between Rs. 13,000 and Rs. 15,000.
Product photo (Prozone) by W and H
Prozone is easy to use and safe to apply as the tissue compatible dosages can be preset according to the indication areas of endodontitis and periodontitis. A hygienic procedure is ensured during the gassing of the pockets as the plastic attachments (Perio tips or Endo tips) [17] are exchangeable. The cost ranges between Rs. 5000 and Rs. 10,000.
Ozotop
It is a compact, easy to use table top unit having a free flow ozone delivery system which utilizes corona discharge. Root canals and periodontal pockets could be easily penetrated. In this system, ambient air is utilized that is filtered and dried before it is passed over a ceramic plate, later high voltage is applied which then finally produces ozone. As this is an open system, high volume suction is required. [18] Depending on requirement of treatment ozone is applied at 6, 12, 18, 24 s (e.g., 12 s - surgical disinfection, 18 s - periodontal disinfection).
Customized thermoformed dental appliance
For application of ozone gas hard- or medium-soft thermoformed dental appliance could be prepared which extends 2-3 mm beyond the affected gingival area and a free space for gas circulation is left. For the inlet and outlet of gas, 2 ports should be attached at distal and mesial of the treatment area, respectively. Light or medium body silicone is used to recline edges of the appliance and light-cured dam applied for complete sealing of the borders. Both hard and soft tissues of the affected area could be treated with this appliance. Indicated areas where such an appliance is hard to use or uncomfortable to the patient, polyvinylchloride (PVC) or silicone cap might be used.
Irrigation with ozonated water
As ozone water is highly effective in killing of both Gram-positive and negative micro-organisms, areas affected during and after scaling, root planing and non-surgical pocket curettage might be irrigated with ozone water. In plaque biofilm, the bactericidal activity of ozone water against bacteria is strong.
Ozone Nano bubble water
As the half-life of ozonated water is about 20 min only because of which it degrades back into oxygen, hence its potency must be assured by using it within first 5-10 min after production. To overcome such a problem CHIBA and TAKAHASHI developed ozone Nano bubble water (NBW3) in 2008. In an electrolyte solution, a micro-bubble (≤50 μm in diameter) collapses by means of a physical stimulus like shock leading to the production of Nano bubble (<100 nm in diameter) under high temperature and pressure. If protected against UV rays exposure, the oxidation ability of NBW3 is retained as aqueous ozone for more than 6 months. NBW3 is used as an adjunctive antiseptic in periodontal treatment due to its bactericidal efficacy and usability. The bactericidal activity of NBW3 is more potent against periodontopathic bacteria than an established oral antiseptic, 0.2% chlorhexidine digluconate.
In-office and home use of ozonized olive oil
A blunt 25-G needle or any other appropriate tip can be used to fill pockets with ozonized olive oil and the application can be repeated once a week.
Peri-implantitis
Gaseous or aqueous form of ozone may be used in cases of peri-implantitis. The abutment is fully covered by cutting an appropriate length of PVC or silicone cap. The gingival borders around the implant should be properly sealed. Ozone gas infiltrations can also be used in this situation. During debridement and curettage, irrigation is done with ozonated water. On the treated areas, 3-4 times daily application of ozonized oil can also be advised.
Desensitization of sensitive root necks
Repeated application of ozone spray for 60 s followed by mineral wash on the exposed dentine provides quick and prompt relief from root sensitivity. The penetration of ionic calcium and fluorine deep into the dentinal tubules is prevented by smear layer present over the exposed root surfaces. This smear layer removal by ozone causes opening of the dentinal tubules by broadening their diameter and thus, the calcium and fluoride ions flow into the tubules easily and deeply. Plugging of these Dentinal tubules prevents the fluid exchange through these tubules. The root sensitivity problem can be effectively terminated by ozone within seconds and also lasts longer than those by conventional methods. [19]
Advantages
- Simple, noninvasive, less time consumption eliminates dental phobia.
Disadvantages include
Ozone toxicity if the level increases at 0.0007% per application, not readily available, instability.
Ozone toxicity
When administered of 0.05 ppm for 8 h ozone is not toxic. A maximum concentration of ozone in oral cavity amounts to 0.01 ppm, during ozone therapy. Certain side-effects are cough, nausea, vomiting, headache, epiphora, rhinitis, upper respiratory irritation, shortness of breath, and heart-related problems. [31]
Contraindications include
Acute alcohol intoxication, pregnancy, severe anemia, recent myocardial infarction, hyperthyroidism, active hemorrhage, and thrombocytopenia.
Ozone intoxication
- Patient must be placed in supine position
- Vitamin E
- Ascorbic acid
- Inhale humid oxygen
- N-Acetylcysteine. [6]
| Conclusion | | |
Ozone therapy is more in contrast to the present conventional therapeutic modalities as it is a minimally invasive and conservative approach, quite inexpensive, painless therapy which increases the acceptability and compliance of patient with minimal adverse effects. However, further research is still needed to justify the routine uses of ozone in dentistry.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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