Mouth Washes – A Paradigm Shift from Chlorhexidine Gluconate to Essential Oil Mouthwash A Meta Analysis

Background: The purpose of this review is to systematically evaluate the effects of an essential-oil mouthwash compared to a chlorhexidine mouthwash with respect to plaque and parameters of gingival inammation. Methods: PubMed databases were searched for studies up to and including may 2015. A comprehensive search was designed and the articles were independently screened. Articles that evaluated the effects of the essential oil mouthwash compared to chlorhexidine mouthwash were included. A meta-analysis was performed, and weighted mean differences were calculated. Results: A total of 17 unique articles were found, of which 11 articles met the eligibility criteria. A meta-analysis of long-term studies (duration > 3 months) showed that the essential oil mouthwash provided signicantly better effects regarding prophylactic plaque control than chlorhexidine Conclusion: In long-term use, the standardized formulation of essential oil mouthwash is more reliable than chlorhexidine mouthwash. analysis random effects the and


Introduction:
Man in the recent times has achieved a giant leap in the eld of dentistry. With the increase in the knowledge and attitude of the newer technological enhanced patients, the concept of treatment is now increasingly been replaced by prevention 1 . The paradigm is now been shifted from disability limitation to treatment of diseases. Gingivitis is not an exemption here. This reversible form of the disease has seen in the last two decades shows a paradigm shift from treatment to prevention. With improvement at genetic and molecular levels, understanding the disease cause and disease progression has now become easier.
With knowledge empowerment in this sector, a lot has been achieved in the treatment and prevention sector. It has been always the mindset of a dental patient that prevention is always better than cure as it is rightly said an ounce of prevention is better than a pound of cure. In the eld of dentistry especially with regards to dentistry rings the bell of chlorhexidine in the mind of the dentist. Gingivitis and various forms of periodontal disease have always been attributed to the complex formation of plaque adherence, accumulation, initiation and progression of disease on the bio lm. Enriched information is now increasingly available on the complex mechanism involved in bio lm and plaque formation 4 . Listerine the rst ever formed essential oil antiseptic was given to the world by Joseph Lawrence Lister in the year 1879 1 . Though this has been introduced almost a millennium to chlorhexidine, the usage of essential oil mouthwashes has been limited for the treatment of halitosis in the dental eld. With the antiseptic chlorhexidine discovery in the 1940's when it was rst introduced to the world by Imperial Chemical Industries in England 1 . 1950's saw chlorhexidine as a popular general antiseptic in comparison with essential oil mouthwash wash 2 . The ability to inhibit oral plaque by chlorhexidine was rst observed by Schroeder in 1969 3 and it was evidenced in a more scienti c manner by Loe and Schiott 1972 4 . From time immemorial plaque buildup was challenged indispensable by chlorhexidine gluconate with practically no replacement or alternate strategies available for it. Since then a war is waged as to which is mightier -chlorhexidine or essential oil mouthwash! Chlorhexidine (CHX) is a broad-spectrum antimicrobial agent that destroys the cell membrane by precipitation and coagulation of the cytoplasmic proteins of the microbial ora. Chlorhexidine mouth rinses are available in the form of 0.2% and 0.12% and it has been show that their e cacy is similar at similar doses 5 . Essential oil mouthwash also inhibits plaque formation by destroying the cell membrane in addition to interference with the in ammatory process. The prophylactic usage of gold standard chlorhexidine and essential oil mouthwash remains a debatable topic. With the usage of antibiotics, chlorhexidine has been scrutinized in the recent times due to complication of resistance and increased staining properties, the usage of chlorhexidine is now warranted. Reports by both the American and British professional societies have now given an insight so as to the usage of prophylactic usage of mouth rinses. Chlorhexidine is still considered as the gold standard for its antimicrobial action but due to increased plaque formation, staining capacity and resistance may now limit its continued use 1 . These Arguments bring us to light about the fact that -chlorhexidine can still be considered as a gold standard for prophylactic prevention or the time has come for its reconsideration.

Materials And Methods:
For this Meta analysis, studies that were randomized clinical trials (RCTs) or controlled trials in healthy human subjects comparing the effects of chlorhexidine gluconate and essential oil mouthwashes on plaque levels for at least 3 months were included. There was no restriction on the amount or percentage of the mouthwashes. The plaque levels in all the included study were taken with one of the following

Results:
The meta analysis done by the random effect models showed that out of eleven studies (table 1) that were analyzed, eight studies favor the use of essential oil mouthwash 9,11,14−19 in-comparison with only one study 13 that favors the effect of chlorhexidine extract. Only two studies 10, 12 remain neutral agreeing to the null hypothesis that there is no difference in the effect of both the mouth washes (Fig. 1).

Discussion:
The prevention treatment of bio lm on the surface of the tooth has been a herculean task for dentists.
The removal of the bio lm can be achieved both at the patient and at the professional level. At the patient level this process of removal is furthermore complicated by the complex dexterity required during mechanical tooth cleaning process 20 . The e ciency of cleaning is both time and technique bound. Hence in order to ease this process, mouth washes are frequently prescribed prophylactically by the dentist. Chlorhexidine has enjoyed being the dentist's favorite prescription for a greater period of time. The effectiveness of chlorhexidine has been well documented. The mechanism of action of chlorhexidine has been thoroughly researched with substantivity remaining undoubtedly the indisputable mechanism of action. Substantivity is de ned as the ability of a substance to bind to tissue surfaces and be released over time, thus providing sustained antibacterial activity 21 . With the increase in the usage antibiotic resistance is now emerging phenomena that has gained popularity and attention. Antibiotic resistance is a serious concern that is now challenging the prophylactic usage in practically all elds.
Studies done by S. M. Clark et al 22 and Carolyne Horner et al 23 have reported signi cant antibiotic resistance. It has also come to light that increased staining of teeth associated with long term chlorhexidine use is now a frequent patient aftermath complaint. Furthermore the usage has now been scrutinized with su cient studies supporting the fact that prolonged chlorhexidine usage is directly proportional with levels of calculus formation. Studies done by Overholser et al, 24 Grossman et al, 25 Charles CH et al 10

Recommendations:
The debatable issue regarding the usage of chlorhexidine and essential oil mouthwashes can now be suggested based on the inference drawn from the present study that: 1. Prophylactic use of chlorhexidine should now be prescribed with caution. Their usage should be encouraged only for therapeutic purposes.
2. Further essential oil mouthwashes can be used for a prolonged interval for prophylactic regime.
3. Essential oil mouthwashes can be used to cater to the needs of the population that require extra care and dexterity that includes the handicapped, differently abled and geriatric population.
4. Longitudinal studies are now required to endorse the fact that chlorhexidine causes increased calculus formation and antibiotic resistance with special regard to oral cavity.

Declarations
The authors declare no competing interests. box forest plot used for the random effects model.