A review of the current literature on management of halitosis

Oral Diseases (2008) 14, 30–39. doi:10.1111/j.1601-0825.2006.01350.x Ó 2007 The Authors. Journal compilation Ó 2007 Blackwell Munksgaard A review of the current literature on management ofhalitosis AMWT van den Broek1, L Feenstra2, C de Baat1 Departments of 1Oral and Maxillofacial Surgery and Special Dental Care and 2Otorhinolaryngology, Erasmus University MedicalCenter, Rotterdam, the Netherlands Halitosis is an unpleasant or offensive odour, emanating social embarrassment. In approximately 80% of all from the oral cavity. In approximately 80% of all cases, cases, halitosis is caused by oral conditions, defined as halitosis is caused by microbial degradation of oral organic oral malodour (Miyazaki et al, 1995; Delanghe et al, substrates. Major degradation products are volatile sul- 1997). There seems consensus that oral malodour results phur-containing compounds. In this review, the available from tongue coating, periodontal disease, periimplant management methods of halitosis and their effective- disease, deep carious lesions, exposed necrotic tooth ness and significance are presented and discussed.
Undoubtedly, the basic management is mechanically wounds, impacted food or debris, imperfect dental reducing the amount of micro-organisms and substrates restorations, unclean dentures and factors causing in the oral cavity. Masking products are not, and anti- decreased salivary flow rate (Yaegaki and Sanada, microbial ingredients in oral healthcare products are only 1992a,b; Morita and Wang, 2001a,b; Morita et al, temporary effective in reducing micro-organisms or their 2001; Kleinberg et al, 2002; Hinode et al, 2003; van substrates. Good short-term results were reported with Steenberghe, 2004; Verran, 2005; Liu et al, 2006).
chlorhexidine. Triclosan seems less effective, essential oils Undoubtedly, the tongue is a major site of oral and cetylpyridinium chloride are only effective up to 2 or malodour production, whereas periodontal disease and 3 h. Metal ions and oxidizing agents, such as hydrogen other factors seem only a fraction of the overall problem peroxide, chlorine dioxide and iminium are active in (Bosy et al, 1994; Stamou et al, 2005; Rosenberg, 2006).
neutralizing volatile sulphur-containing compounds. Zinc The oral malodour arises from microbial degradation seems to be an effective safe metal at concentrations of at of organic substrates present in saliva, crevicular fluid, least 1%. The effectiveness of active ingredients in oral oral soft tissues and retained debris. Major microbial healthcare products is dependent on their concentration degradation products are volatile sulphur-containing and above a certain concentration the ingredients can compounds (Tonzetich, 1977). Non-oral aetiologies of have unpleasant side effects. Tonsillectomy might be halitosis include disturbances of the upper and lower indicated if (i) all other causes of halitosis are managed respiratory tract, some systemic diseases, metabolic properly; (ii) halitosis still persists and (iii) crypts in tonsils disorders, medications and carcinomas (Tangerman, are found to contain malodorous substrates.
2002). The three primary methods for measuring hali- tosis are organoleptic measurement, gas chromatogra-phy and sulphide monitoring.
Before halitosis may be managed effectively, an accurate diagnosis must be achieved. An accuratediagnosis depends on analysis of data collected frompatient history and physical examination. The patient history should contain main complaint, medical, dental Halitosis is an unpleasant or offensive odour emanating and halitosis history, information about diet and habits, from the oral cavity, leading to discomfort and psycho- and third part confirmation confirming an objectivebasis to the complaint. Parts of the physical examinationare extraoral examination, intraoral examination with Correspondence: Ms AMWT van den Broek, Department of Oral and special attention paid to the tongue and the periodontal Maxillofacial Surgery and Special Dental Care, Erasmus University tissues, and upper respiratory tract examination. After Medical Centre, PO Box 2040, 3000 CA Rotterdam, the Netherlands.
taking history and proper physical examination, halito- Tel: +31 (0) 10 4633955, Fax: +31 (0) 10 4633098, sis can be classified into categories of genuine (oral or E-mail: [email protected] 17 May 2006; revised 30 August 2006; accepted 1 October 2006 extraoral) halitosis, pseudo-halitosis and halitophobia Management of halitosisAMWT van den Broek et al (Murata et al, 2002). Pseudo-halitosis is obviously not sulphur-containing compounds in morning breath after perceived by others, although the patient stubbornly consumption of a hard, dry bread roll, without any oral complains of its existence. Halitophobia is diagnosed if cleaning procedures (Suarez et al, 2000).
no physical or social evidence exists suggesting that Extreme hyposalivation increased the production of halitosis is present, whereas the patient persists in volatile sulphur-containing compounds (Kleinberg et al, believing that he or she has halitosis. Pseudo-halitosis 2002; Koshimune et al, 2003). However, between a and halitophobia are further left out of consideration.
group of healthy patients with, and a control group In this review, the available management methods of without halitosis, no differences in salivary flow rate genuine halitosis, their effectiveness and significance for were found (Oho et al, 2001). In an earlier study, both clinicians and patients are presented and discussed.
variations in the level of unstimulated saliva could not The available methods leading to lowering of oral explain the variance in volatile sulphur-containing malodour level can be divided into: usage of masking compounds in a group of subjects with bad breath products, mechanical reduction of micro-organisms and (Rosenberg et al, 1991). A lower level of saliva during their substrates, chemical reduction of micro-organisms, the night is physiological. The level of saliva may be and chemical neutralization of odorous compounds, lowered as well by mouth breathing or snoring. The effect, bad morning breath, may be quite easily treated Patients diagnosed as suffering from non-oral halitosis by salivary stimulation. Salivary stimulation by eating should be referred to a clinic for otorhinolaryngology or breakfast, chewing or consuming acid food and saliva internal medicine for appropriate treatment.
substitutes diminished the effect of hyposalivation(Norris et al, 1984; Mackie and Pangborn, 1990; Klein-berg and Westbay, 1992; Edgar et al, 1994; Bots et al, Usage of masking products only is never a real Chewing gum may have a mechanical role in stimu- management of halitosis. Nevertheless, some commer- lating the salivary flow and thus cleaning surfaces of cially available products, such as mints, toothpastes, teeth (Edgar et al, 1994; Reingewirtz et al, 1999; Bots mouthrinses, sprays and chewing gums, attempt to et al, 2004). However, by cysteine challenge testing was control halitosis with pleasant flavours and fragrances.
demonstrated that chewing of a gum without any active Mints and chewing gum without active ingredients had ingredient reduced halitosis only modestly (Wa˚ler, no significant effect on tongue dorsum malodour 3 h 1997a). The basis of cysteine challenge testing is rooted after use (Greenstein et al, 1997; Yaegaki et al, 2002).
in two fundamental aspects of the halitosis process.
After 3 h, similar organoleptic and sulphide monitor When broken down by oral bacteria, cysteine produces scores were observed for subjects who chewed either a hydrogen sulphide. This volatile product, when ionized, menthol-containing gum or a neutral unsweetened gum contributes to the lowering of the oxidation–reduction or no gum. A short masking effect appeared only with potential, which is the primary physico-chemical factor the menthol-containing gum and may be the result of favouring growth of Gram-negative oral anaerobes the menthol (Reingewirtz et al, 1999).
(Kleinberg and Codipilly, 2002). Sugarless chewinggum had no effect on volatile sulphur-containingcompounds concentrations (Yaegaki et al, 2002).
Mechanical reduction of micro-organismsand their substrates Brushing the teeth, flossing, using toothpicks Mechanical reduction of micro-organisms and their Mechanical cleaning of teeth, such as brushing the teeth, substrates can be achieved by taking a solid breakfast, flossing and using toothpicks reduced the amount of improving hyposalivation, using chewing gum, brushing oral bacteria and substrates, thereby presumably redu- the teeth, flossing, using toothpicks, tongue cleaning and cing oral malodour (Coil et al, 2002; Tanaka et al, 2003). However, clinical studies revealed that brushingthe teeth exclusively was not very effective in reducing Breakfast, improving hyposalivation and chewing gum oral malodour scores (Yaegaki and Sanada, 1992c; Fasting, during longer periods or during the night, was Kleinberg and Codipilly, 2002). Furthermore, in sub- suggested as being a physiological cause of temporary jects free of caries, periodontal disease and tongue halitosis, so-called bad morning breath, resulting from coating, exclusively brushing the teeth had no appreci- stagnation of epithelial and food debris on the soft oral able influence on the concentration of volatile sulphur- tissues. Passage of solid food over the surface of the tongue could remove the tongue coating (Kleinberg and compared with no brushing and rinsing the mouth with Westbay, 1992). Subjects who exhibited early morning halitosis, showed significant reductions of hydrogensulphide by 60% and methyl mercaptan concentrations by 83% 1 h after breakfast, without any oral cleaning Various instruments can be applied to the tongue and by procedures (Tonzetich and Ng, 1976). Subjects who gentle pressure the majority of the tongue coating can be were free of caries, periodontal disease and visible scraped off (Yaegaki et al, 2002). Brushing the dorsum of the tongue with a toothpaste was more effective than cally substantially reduced concentrations of volatile brushing the teeth. Levels of volatile sulphur-containing compounds could be reduced for at least 1 h by mouthrinse produced significant reductions in volatile brushing the teeth and the tongue, and then rinsing sulphur-containing compounds levels and in organolep- the mouth with water (Tonzetich, 1971, 1978; Tonzetich tic scores (Rosenberg et al, 1991; van Steenberghe et al, and Ng, 1976). Other studies found a relationship 2001; Carvalho et al, 2004). Similar results with 0.12% between tongue cleaning and the reduction of both chlorhexidine-(di)gluconate were reported in combina- organoleptic scores and levels of volatile sulphur- tion with teeth and tongue brushing (Bosy et al, 1994; containing compounds (Bosy et al, 1994; Suarez et al, De Boever and Loesche, 1995). A mouthrinse containing 2000; Seemann et al, 2001). In patients with high levels 0.025% chlorhexidine was only moderate effective, of oral malodour, a regular toothbrush was statistically whereas a concentration of 0.2% was much more significantly less effective in tongue cleaning than a effective and even showed a tendency to improved effect device that brushed and scraped, or a scraper. Because during 3 h (Young et al, 2003a). In adolescents with of the limited duration of the effect, the efficacy halitosis, organoleptic scores were significantly reduced remained questionable (Seemann et al, 2001). Scraping after tongue cleaning with a hard toothbrush, wetted the tongue after cysteine challenge testing reduced with 0.12% chlorhexidine gluconate. It was not possible halitosis only modestly, but brushing the tongue dorsum to discriminate between the influence of the mechanical was remarkably effective (Kleinberg and Codipilly, cleaning and the chlorhexidine (Cicek et al, 2003).
2002). Two weeks of tongue brushing or scraping by a Therefore, it is uncertain if the results were due to group of patients free of periodontitis resulted in chlorhexidine, to cleaning of the teeth and the tongue, or negligible reductions in bacteria on the tongue, whereas to both. Chlorhexidine has the side effects of tooth the amount of tongue coating decreased significantly.
staining and an unpleasant taste at concentrations from Therefore, tongue cleaning seems to reduce the sub- at least 0.2% (Jones, 1997; Young et al, 2003a). Tooth strates for putrefaction, rather than the bacterial load staining seems to be the result of a local precipitation chromogens found within foodstuffs and drinks. Fur- thermore, the activity of chlorhexidine is reduced in the Professional oral health care was delivered by dental presence of anionic agents, found in certain types of hygienists once a week to a group of elderly patients, toothpaste (Jones, 1997). Chlorhexidine concentrations needing daily nursing care. The dental hygienists cleaned in mouthrinses till 0.12% and mucosa exposure not the teeth, the dentures, the buccal mucosa and the exceeding 1 min twice a day, seem the best procedure to tongue. They used hand scalers, an electric toothbrush, protect tastes in clinical practice (Marinone and Savoldi, an interdental brush and a sponge brush. A control group received only denture cleaning and swabbing theoral cavity with a sponge brush. The professional care reduced the levels of methyl mercaptan significantly (Adachi et al, 2002). Patients with periodontitis under- phenylether, is the most widely used antibacterial and went a one-stage full-mouth disinfection, combining antiplaque agent in oral care products. It is insoluble in scaling and root planing of teeth with the application of water and has to be solubilized in organic solvents or chlorhexidine, or consecutive root planings per quad- detergents. Triclosan has a broad spectrum of antimi- rant at a 1- to 2-week interval. The full-mouth disinfec- crobial activity against bacteria, especially the Gram- tion resulted in a faster and additional reduction negative anaerobic species (Brading et al, 2004). The in organoleptic scores, even after 2 months. However, antimalodour effect was not maintained when oils, oily the levels of volatile sulphur-containing compounds substances and uncharged detergents were used as remained unchanged in both groups (Quirynen et al, solubilizers (Young et al, 2002). A toothpaste contain- ing 0.3% triclosan, 2.0% of a copolymer of polyvinylmethyl ether maleic acid and 0.243% sodium fluoridehas been shown in double-blind clinical trials to be significantly better than a placebo toothpaste in redu- Toothpastes and mouthrinses with antimicrobial prop- cing organoleptic scores up to 12 h. However, the erties can reduce oral malodour by reducing the number benefit of triclosan was relatively small, when compared of micro-organisms chemically (Brading and Marsh, with the placebo toothpaste. The copolymer is claimed 2003). Often used active ingredients in these products to improve the retention of the triclosan within the oral are chlorhexidine, triclosan, essential oils and cetylpy- cavity (Niles et al, 1999; Sharma et al, 1999). Addition ridinium chloride. Other effective chemical agents are of a special grade of silica did not further improve the allylpyrocatechol, L-trifluoromethionine and dehydro- efficacy of the toothpaste in reducing organoleptic scores (Sharma et al, 2002). The same toothpaste was associ-ated with a significant decrease of hydrogen sulphide- producing bacteria (Sreenivasan, 2003; Vazquez et al, Chlorhexidine has a bactericidal and bacteriostatic 2003). An increase of volatile sulphur-containing com- antiplaque effect as a result of the dicationic nature of pounds, occurring during the development of experi- the chlorhexidine molecule (Addy and Moran, 1997; mental gingivitis, was reduced by toothpastes containing Jones, 1997). In several studies, a 0.2% chlorhexidine 0.3% triclosan (Nogueira-Filho et al, 2002). Raising the Management of halitosisAMWT van den Broek et al level of triclosan from 0.2% to 0.3% in a calcium closely related to some oral mucosal lesions, such as oral carbonate-based system, was suggested enhancing its submucous fibrosis, oral leukoplakia and oral cancer (Jeng et al, 2001; Avon, 2004). Arecoline and safrole arethought to be the major toxic ingredients in betel quid (Shieh et al, 2003). Study results exhibited marked In the history of mankind, the Egyptians made exten- depression of the volatility of methyl mercaptan by sively use of essential oils for cosmetics as well as betel quid and by a mixture of areca fruit and slaked medicinal purposes. Among others the products were lime paste. The depression was more marked when used in the embalming process. During the following increasing amounts of slaked lime paste were added or periods, the medicinal properties of essential oils were when the slaked lime paste was replaced with alkaline applied for several health problems. Essential oils are salts (Wang et al, 2001). A bioassay-guided fraction- odorous, volatile products of plant secondary metabo- ation yielded allylpyrocatechol as the major active lism, many of them possessing strong antimicrobial principle. This non-toxic product showed promising properties (Kalemba and Kunicka, 2003). The short- antimicrobial activity against obligate anaerobes (Ramji term effect of a mouthrinse containing essential oils and menthol was evaluated in comparison with a placebo.
Based on its masking effect, the experimental mouth- rinse was more effective against oral malodour than the Methyl mercaptan arises from the bacterial metabolism placebo during 0.5 h. At 1 h and up to 3 h, the greater of methionine. It was shown with an in vitro study that effectiveness was maintained by a sustained reduction in the growth of Porphyromonas gingivalis, a periodontal the levels of odorigenic bacteria (Pitts et al, 1981, 1983).
micro-organism that produces large amounts of mer- In clinical trials, an essential oil-containing toothpaste captan, was strongly inhibited by L-trifluoromethionine, as well as an essential oil-containing toothpaste with a fluorinated derivative of methionine (Yoshimura et al, addition of 1% zinc citrate, were significantly and equally more effective than a control toothpaste inreducing oral malodour from 1.5 to 2 h (Olshan et al, Full-strength oxidizing lozenges were effective in redu-cing tongue malodour over a period of 3 h (Greenstein et al, 1997). The effect may be due to the activity of Quaternary ammonium compounds, such as benzalko- dehydroascorbic acid, generated by peroxide-mediated nium chloride and cetylpyridinium chloride, inhibit oxidation of ascorbate present in the lozenges.
bacterial growth (Xiong et al, 1998). A chromatograph-ically determined significant reduction in both the hydrogen sulphide and methyl mercaptan levels of subjects with good oral health was reached with amouthrinse, containing a quaternary ammonium com- Toothpastes, mouthrinses, lozenges and other products pound and alcohol (Solis-Gaffar et al, 1975). Daily can reduce halitosis by chemically neutralizing odorous usage of a two-phase oil–water mouthrinse containing compounds, including volatile sulphur-containing com- cetylpyridinium chloride reduced oral malodour over a pounds. Often used active ingredients of these products 6-week period, when compared with a similar mouth- are metal ions and oxidizing agents. Metals, such as rinse without cetylpyridinium chloride (Kozlovsky et al, zinc, sodium, stannous and magnesium are thought to 1996). A similar cetylpyridinium containing mouthrinse interact with sulphur. The interaction forms insoluble was effective with an 80% reduction of volatile sulphur- sulphides. The mechanism proposed is that metal ions containing compounds during 3.5 h (Yaegaki and oxidize the thiol groups in the precursors of volatile Sanada, 1992c). Using cysteine challenge testing, a sulphur-containing compounds (Tonzetich, 1978; Ng mouthrinse containing cetylpyridinium plus domiphen and Tonzetich, 1984). However, no positive correlation bromide was minimally effective in reducing halitosis was found between metal ions affinity for sulphur and (Kleinberg and Codipilly, 2002). Also using cysteine their inhibiting effect on volatile sulphur-containing challenge testing, a mouthrinse containing 0.025% compounds (Wa˚ler, 1997b). Oxidizing agents might cetylpyridinium was not more effective than water, reduce halitosis by reducing conditions necessary for whereas a concentration of 0.2% was only moderately metabolizing sulphur-containing amino acids to volatile Betel quid, composed of Piper betel leaves or inflores- Mouthrinses containing zinc were effective in reducing cences, fresh areca fruit and slaked lime paste, is a oral malodour, as registered by the usual measurement natural masticator in many countries. Tobacco can be methods (Schmidt and Tarbet, 1978; Tonzetich, 1978).
added to the mixture, but betel leaves are also chewed Zinc has to be present in a specific quantity. The exclusively. Among others, it is used to remove halitosis addition of 0.5 mg zinc acetate to a mouthrinse and a (Wang et al, 2001; Ramji et al, 2002). However, epide- chewing gum showed no significant effect, but the miological studies showed that betel quid chewing is addition of 2 mg resulted in significant reductions of 45% of volatile sulphur-containing compounds levels was reported of severe hypermagnesaemia, following (Wa˚ler, 1997a). Using cysteine challenge testing, a chronic gargling with Epsom SaltÒ, which resulted in mouthrinse containing zinc chloride was effective in coma, cardiopulmonary arrest, and finally the death of reducing halitosis, depending on the concentration. At a concentration of 12 mM zinc, the effectiveness was morepronounced and prolonged than at a concentration of 3 mM (Kleinberg and Codipilly, 2002). A mouthrinse The potential of hydrogen peroxide for reducing the containing 1% zinc was most effective 1 h after use, but levels of salivary thiol precursors of oral malodour was was still very effective after 3 h. The mouthrinse had a investigated in 10 volunteers. The mean reduction by somewhat unpleasant taste, whereas a 0.1% concentra- 1-min tooth brushing with a toothpaste containing tion was found acceptable, but had only a minor effect.
0.67% hydrogen peroxide and 5.48% sodium bicar- The unpleasant taste may be overcome in commercial bonate was 59% 0.5 h after application. However, it products by masking with other ingredients (Young was not possible to discriminate between the influence of hydrogen peroxide and of sodium bicarbonate.
Other studies revealed that sodium bicarbonate is not or only minimally active at concentrations below 20% There is a long tradition of using sodium bicarbonate in (Grigor and Roberts, 1992; Brunette et al, 1998). In oral cleaning in Japan. Also in North America, many subjects free of caries, periodontal disease and visible people like to use sodium bicarbonate to clean their tongue coating, mouth rinsing with 3% hydrogen teeth. The popular name of this product is baking soda.
peroxide produced reductions of up to 90% of oral The effectiveness of toothpastes containing sodium volatile sulphur-containing compounds in morning bicarbonate in reducing oral malodour was indicated breath for 8 h, measured chromatographically (Suarez subjectively and also organoleptically and chromato- graphically in reducing the amounts of volatile sulphur-containing compounds (Brunette, 1996). Toothpastes containing 20% or more sodium bicarbonate had a Chlorine dioxide (ClO2) has the power to oxidize the significant malodour-reducing effect for time periods up amino acids methionine and cysteine, both precursors of to 3 h (Brunette et al, 1998). Additional studies are volatile sulphur-containing compounds (Lynch et al, needed to determine how sodium bicarbonate might be 1997). Using a liquid-air spray device, halitosis patients applied most effectively, for instance in toothpaste or were treated with professional cleaning and irrigation of mouthrinse. Furthermore, studies are needed to find out all soft tissues in the mouth with aqueous ClO2. The the working mechanism of sodium bicarbonate. As yet, clinical results were very good, but it was impossible to it is not clarified if the effect is real bactericidal or discriminate between the effect of professional cleaning a transformation of volatile sulphur-containing compo- and the ClO2 (Richter, 1996). One double-blind, cross- over study demonstrated that a single use of a ClO2-containing mouthrinse slightly reduced oral malodour in patients with slightly unpleasant organoleptic scores A toothpaste-containing stannous fluoride was more effective than water, 8 h after tooth brushing, but the double-blind, parallel group study in similar patients patients still suffered from halitosis (Gerlach et al, revealed that the same mouthrinse significantly reduced 1998). Toothpaste containing stannous fluoride and volatile sulphur-containing compounds concentrations amine fluoride showed only minor changes in volatile in mouth air for at least 8 h post rinsing (Frascella et al, sulphur-containing compounds in morning breath of 2000). Using cysteine challenge testing, the effectiveness students who refrained from oral hygiene procedures of a mouthrinse containing 1.0% sodium chlorite (NaClO2) was more pronounced and prolonged thanat a concentration of 0.1% (Kleinberg and Codipilly, Epsom SaltÒ, an agent originally developed in 1695 andderived from a well in Epsom, England, is used as a cathartic in patients with impaired renal function or Sanguinarine has been demonstrated to be effective in treating eclampsia of pregnancy (Morris et al, 1987; chemically neutralizing volatile sulphur-containing com- Nordt et al, 1996). It contains almost 100% magnesium pounds, based on its unique chemical iminium structure.
sulphate. Toxicity is uncommon in healthy subjects at Iminium is a non-metal oxidation catalyst, which, at doses of around 10 g day)1. Minor elevation of serum physiological acidity levels, is able to neutralize cysteine magnesium, is characterized by nausea, headache, as well as hydrogen sulphide and methyl mercaptan flushing, warmth and lightheadedness. At higher doses the cardiovascular, respiratory and neuromuscular sys-tems are affected. Magnesium in serum has the risk of hypermagnesaemia. In large doses, magnesium acts like If different halitosis-reducing agents and ingredients curare (Ferdinandus et al, 1981). In rare cases, people operate by different mechanisms, it is conceivable that are using Epsom SaltÒ as a gargle for halitosis. A case combinations may provide an enhanced or synergistic Management of halitosisAMWT van den Broek et al effect. Some combinations have demonstrated enhanced Table 1 Results of ten relevant studies comparing the effect of several or synergistic effectiveness in clinical trials.
A chlorhexidine and zinc mouthrinse had a strong effect on volatile sulphur-containing compounds and was effective for at least 9 h. Control rinses with chlorhex- idine or zinc alone had a respectively moderate and strong effect for 1 h, but these effects diminished with time, respectively, fast and slightly (Young et al, 2003b).
Zn2+ > triclosanZn2+ > Na+/triclosan A cetylpyridinium chloride and zinc mouthrinse had a good synergistic effect on volatile sulphur-containing compounds levels after 1 h, but minimal above the effect Chlorhexidine, cetylpyridinium chloride and zinc A solution containing chlorhexidine, cetylpyridium chloride and zinc lactate, was more efficient in reducing organoleptic scores and levels of volatile sulphur- containing compounds than a placebo mouthrinse (vanSteenberghe et al, 2001; Quirynen et al, 2002; Rolda´n CHX, chlorhexidine; CPC, cetylpyridinium chloride; EO, essential oils;ClO et al, 2003). The effectiveness of this solution was 2, chlorine dioxide; Alc, alcohol; Sn2+, stannous; Na+, sodium; Zn2+, zinc; Cu2+, cupric; Am+, amine; /, in combination with; >, confirmed in a double-blind placebo-controlled study effect significantly better than …; ¼, effect not statistically significant managing halitosis, though there are no clinical studies The addition of 2% zinc to sodium bicarbonate con- supporting this treatment. Only if other causes of taining toothpastes diminished chromatographic meas- halitosis are managed properly and halitosis still per- urements significantly after 3 h (Brunette et al, 1998).
sists, and if crypts in tonsils are found to contain Using cysteine challenge testing, a mouthrinse freshly malodorous substrates, tonsillectomy may be indicated combining 0.1% NaClO2 and 6 nM zinc chloride, was (Darrow and Siemens, 2002). Clinical studies are exclu- much more effective when compared to separate mouth- sively reported on Helicobacter pylori infection, the rinses with 0.1% NaClO2 or 6 nM zinc chloride. If the main factor of inflammatory and ulcerative changes in agents were combined and left for 4 days, the effective- the gastric mucosa (Hoshi et al, 2002). One report is ness was drastically reduced and further deterioration presented on management of malodorous intestinal continued with time (Kleinberg and Codipilly, 2002).
gases by Escherichia coli (Henker et al, 2001).
Sanguinarine, containing iminium, in combination with If clinical examination in 260 halitosis patients did not zinc was 67% more effective in reducing volatile reveal any cause, a C13-urea test for detecting H. pylori sulphur-containing compounds from incubated saliva was carried out. Twenty-one tests were performed and than zinc alone (Boulware and Southard, 1984).
seven (33.3%) were positive. This percentage was similarto the percentage of positive tests, found in the Ônormal’ Comparison of different (combinations of) agents European population. Three patients started a therapy The results of studies on the effectiveness of oral of amoxicillin, metronidazole and omeprazole. How- healthcare products containing ingredients against hali- ever, none of them noticed a decrease of halitosis tosis are controversial and sometimes contradictory.
Ten relevant studies have been carried out to compare Omeprazole and amoxicillin significantly reduced the effect of several products (Rosenberg et al, 1992; sulphide monitor and organoleptic scores in about Kozlovsky et al, 1996; Gerlach et al, 1998; van Stee- 80% of H. pylori-positive dyspeptic patients, whereas nberghe et al, 2001; Young et al, 2001; Borden et al, mouth rinsing with chlorhexidine failed. The remaining 2002; Quirynen et al, 2002; Ro¨sing et al, 2002; Carvalho 20% of patients were positively treated by omeprazole, et al, 2004; Rolda´n et al, 2004). The results of these amoxicillin and clarithromycin. Unfortunately, these patients were not examined for intraoral causes ofhalitosis (Ierardi et al, 1998).
In children with H. pylori infection, symptoms of halitosis were assessed by a questionnaire. After 6 weeks Reports on management of non-oral aetiologies are very therapy by lansoprazole, amoxicillin and clarithromy- scarce. Tonsillectomy is often cited as in indication for cin, the halitosis scores were improved significantly.
Eradication of bacteria was achieved in only 56% of • oral malodour measurements at a minimum of two appropriate time periods after baseline during Helicobacter pylori-positive patients, who showed no organic lesions on endoscopic examination and no • organoleptic examination by two trained and calib- atrophy of the gastric mucosa histopathologically, rated odour judges or measurement of volatile received omeprazole, amoxicillin and clarithromycin.
sulphur-containing compounds using gas chroma- Endoscopic examination was carried out before and 4–6 weeks after therapy, and halitosis was investigated • evidence of significant reductions in oral malodour by a questionnaire. Patients and their relatives were questioned. The patients with confirmed H. pylori • evidence that at least 80% of the subjects demon- eradication (74%), reported halitosis reduced from strate a reduction to questionable or no oral 61% to 3%. Again, patients were not examined for malodour at some time during the management intraoral causes of halitosis (Serin et al, 2003).
• evidence that microbial resistance does not occur.
None of the studies mentioned in this review meet all A girl with increased formation of malodorous intestinal ADA-guidelines. Any future study should meet these gases was successfully treated with a suspension of living requirements in order to provide evidence-based results.
non-pathogenic bacteria E. coli. The concept of this Nevertheless, within the limitations of the studies treatment is to re-colonize the intestinal tract with reviewed, some careful conclusions can be drawn.
normal or other intestinal bacteria and therefore Undoubtedly, the basic management of halitosis is suppress those contributing to the formation of mechanically reducing the amount of micro-organisms malodorous gases (Henker et al, 2001).
and substrates in the oral cavity, with a special attentionto the tongue. For subjects with healthy oral conditions and only early morning halitosis, taking a solid break-fast is an effective natural mechanical method.
The American Dental Association has established Masking products are not effective in reducing micro- Acceptance Program Guidelines applying to products organisms or their substrates and in neutralizing odor- designed for managing oral malodour of non-systemic ous compounds. With some masking products, such as origin (American Dental Association, 2003; Wozniak, menthol and mint, only a short-term masking effect of 2005). Products considered are active chemical agents as <2 h of halitosis can be expected.
well as mechanical means. Regarding safety and efficacy Chemical reduction of micro-organisms by antimi- crobial ingredients in oral healthcare products is only • clinical study of oral soft tissues and teeth; temporary effective. The effectiveness of the ingredients • monitoring oral flora for the development of is dependent on their concentration and above a certain opportunistic and pathogenic organisms during a concentration the ingredients may have unpleasant side effects. Good short-term results were reported with 3 weeks and 6 months, unless the product has chlorhexidine. Triclosan seems less effective. Essential already been used for plaque and gingivitis control oils and cetylpyridinium chloride are only effective for or whose active ingredient is generally recognized short-time periods of up to 2 or 3 h. Allylpyrocatechol, L-trifluoromethionine and dehydroascorbic acid could • assessment of gingival inflammation with an appro- be promising antibacterial agents. No clinical trials were found comparing the effect of antimicrobial ingredients • examination of pathological conditions, such as in oral healthcare products with the effect of mechan- allergic reaction, oral ulceration, candidiasis and ically reducing bacteria and substrates. Chemical ingre- dients of oral healthcare products seem most effective • examination of effect on hard tooth tissues and when applied in addition to instructions in oral hygiene restorative materials, such as staining, shade alter- and professional mechanical cleaning (Quirynen et al, • assessment of possible toxic or adverse effects; Metal ions and oxidizing agents are active ingredients • patient reports of any changes in taste, saliva flow, of oral healthcare products for chemically neutralizing burning sensation, xerostomia or other characteris- volatile sulphur-containing compounds. Again, the effectiveness of the active ingredients is dependent on • two independent 3-week clinical studies utilizing an their concentration and above a certain concentration the ingredients can have unpleasant side effects. Zinc seems • crossover or parallel group study design; to be an effective safe metal at concentrations of at least 1%. Oxidizing agents, such as hydrogen peroxide, ClO2 • study population of individuals from 21 to 65 years and iminium are reported to be effective for longer of age with intrinsic oral malodour of oral origin; periods of time in patients with slightly unpleasant • exclusion of subjects with advanced periodontitis halitosis. These agents could be used in addition to daily and subjects who smoke or wear oral appliances; mechanical cleaning in order to reach a day-long effect.
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