Xylitol is a naturally occurring sweetener

Transcription

1 and your teeth

2 What is xylitol? How does it work? Studies have proven that xylitol is an important supplement in the prevention of dental caries. Finnish scientists discovered the uses of xylitol in dentistry in the early 1970 s. Further research into xylitol chewing gum and xylitol pastilles has set the trend, making xylitol an integral part of dental health promotion. The benefits of xylitol are gaining increasing recognition on a worldwide scale. Xylitol is a naturally occurring sweetener Xylitol is a sweetener that occurs naturally. It can be found in such foods as berries, fruit, vegetables and mushrooms. It is even generated by the human body during metabolism. The Finnish name for it,

3 koivusokeri, or birch sugar, derives from the fact that the original way to make xylitol industrially is from birch, by chopping up and rendering down the structural fibre of the wood, xylan. Chemically speaking, xylitol is a 5-carbon polyol sweetener, a sugar alcohol. It differs from other sweeteners such as sorbitol, fructose and glucose because the xylitol molecule has five, instead of six, carbon atoms and the caries-causing bacteria are not able to effectively use xylitol for growth. That is one reason why xylitol helps prevent caries. Xylitol is much sweeter than such substances as sorbitol. It has the same degree of sweetness as sucrose (i.e. ordinary sugar), but 40% less calories. Xylitol has a pleasant cooling effect in the mouth.

4 The course of an acid attack Streptococcus mutans bacteria are the primary cause of tooth decay. S. mutans is a common bacterium that lives in the plaque that is continually building up on the teeth. Every bite of food gives the bacteria energy, allowing them to multiply and start producing acid by a metabolic process. The result is the infamous acid attack. When the ph of this mass of bacteria, or plaque, falls below ph 5.5, calcium and phosphate salts start dissolving from the surface of the enamel. Cavities begin to form, though only very slowly at first. After each meal or snack, it takes over half an hour before the ph of the plaque is restored to the normal level of around 7. If you eat several times a day, salts are dissolved off the enamel more and more deeply and the enamel becomes porous. Xylitol stops acid attack When you take xylitol, the acid attack that would otherwise last over half an hour is stopped in its tracks. Because the bacteria in the mouth causing caries are unable to ferment xylitol in their metabolism, their growth is reduced. The number of acid-producing lactobacilli and streptococci bacteria falls by as much as 90%. Because acids are not formed, the saliva and plaque ph do not fall. The absorption of the bacteria on tooth surfaces is weakened and the amount of plaque decreases.

5 Xylitol stimulates protective saliva and corrects incipient damage to enamel In addition to its effects on bacteria, the sweetness of xylitol stimulates the secretion of saliva. Saliva in itself protects the mouth and teeth. Xylitol also relieves the problem of dryness in the mouth. Saliva containing xylitol is more alkaline than the saliva stimulated by other sweeteners. This means that the buffer capacity of the saliva as well as its calcium and phosphate content rise causing remineralisation of caries damage. Thus any softening of the enamel begins to harden again. Xylitol reduces transmission of Streptococcus mutans bacteria The so-called Mother child study confirms that maternal xylitol chewing gum consumption reduces the mother-child transmission of Streptococcus mutans bacteria, which are the primary cause of tooth decay. The first two years of a child s life are the most important in caries prevention. The study indicates that, in future, intervention against mutans streptococci colonisation may lead to better caries prevention than the traditional caries measures concentrating on increasing the resistance of the teeth. Xylitol helps prevent caries remineralises caries lesions reduces caries rates helps reduce build-up of plaque stimulates saliva How to use xylitol Use chewing gum or pastilles with an adequate xylitol content (min. 50% of all sweeteners) after every meal or snack 3-5 times a day (a daily dose of 5 grammes) regularly on a long-term basis 5-10 minutes at a time

6 World xylitol research The effect of xylitol on the prevention of dental caries has been established in long-term scientific studies. The dental significance of xylitol was discovered in Finland in the so-called Turku sugar studies carried out in by professors Kauko K. Mäkinen and Arje Scheinin at Turku University. Another important milestone was the Ylivieska field studies in Ylivieska, Finland in These studies showed for the first time that the consumption of relatively small daily quantities of xylitol can have a long-term effect on dental caries, and that such use of xylitol can even permanently prevent caries. The first chewing gum to be sweetened with xylitol and to have anticariogenic effects, Xylitol-Jenkki, was launched in 1975 by Leaf. Kauko K. Mäkinen The Michigan xylitol programme: Xylitol chewing gum plays a valuable role in caries prevention and stabilisation The aim of the Michigan Xylitol Programme ( ) was to study the use of xylitol-containing saliva stimulants in the prevention of dental caries. The studies undertaken in this programme consisted of several clinical trials and laboratory investigations and were carried out in Belize (Central America), Michigan, Ohio, Finland and Estonia. The results of the ten-year research project confirm that a chewing gum sweetened 100 % with xylitol plays a valuable role in caries prevention and stabilisation. Such chewing gum used in The Michigan Xylitol Programme was provided by Leaf Finland. The gum was developed and launched as a result of the programme. The Belize Xylitol Chewing Gum Trials In a chewing gum trial on permanent dentition ( ), effects of chewing gum use on the increment of dental caries were compared as a function of sweetener type, proportion of specific sweeteners in the gums, and frequency of chewing, initially in 10-year-old subjects in a 40-month double-blind cohort study. This study was carried out in Belize. The caries prevalence in Belize has been high. The chewing gums had comparable organoleptic properties and essentially the same aggregate percentages of polyols or sugars, comprising either xylitol, sorbitol or sucrose. The chewing gums in the form of either sticks or pellets were chewed either 3 or 5 times/day, during the school year. Gum with high xylitol content has a remineralising effect In long-term dental trials in Belize, the regular consumption of xylitol chewing gum with the highest xylitol content has been shown to have a clear remineralising effect. The xylitol content

7 started in Finland is evidently in direct relation to the degree of caries reduction: the higher the xylitol content, the more effectively caries reduction was achieved. There was also a correlation between frequency of use and results. Nine groups were studied, comprising 1277 subjects. One control group was provided with no gum at all; four xylitol gum-chewing groups received either pellet- or stick-shaped gum for either 3 or 5 supervised sessions/school day; one group used sorbitol pellet gum for 5 sessions/school day; two groups used either xylitol or sorbitol pellet gums 5 times/school day; one group used sucrose gum 5 times/school day. The primary response variable was the development of frank carious surface lesions, which were detectable by the physical loss of enamel and probable extension of lesions to the dentine for those tooth surfaces, which were not cavitated at the baseline or which had not erupted at the baseline. Statistical comparisons were made according to the relative risk for caries associated with the use of each of the chewing gum types, when compared to the Nogum group. The use of 100 % xylitol chewing gum had the most significant caries- preventing effect The findings of the research show that there is an anti-caries hierarchy among polyol-sweetened chewing gums. Although sorbitol-sweetened gum is clearly less cariogenic than sugar gum, combination with xylitol decidedly enhances its anticaries effectiveness, which becomes much greater when the ratio of xylitol to sorbitol is increased to 3:2 (See table below) The largest caries reductions were observed in a group receiving 100% pellet- shaped xylitol chewing gum. The sorbitol and xylitol/sorbitol mixture gums were less effective than the 100% xylitol gum, but they still reduced caries rates significantly when compared to the No-gum or sucrose gum. All xylitol- containing gums reduced the relative risk of caries increment compared to sugar, no-gum and sorbitol gum. References Mäkinen, K.K., Hujoel, P.P., Bennett, C.A., Isotupa, K.P., Mäkinen, P.-L. and Allen, P Polyol chewing gums and caries rates in primary dentition: a 24-month cohort study. Caries Research. 30: Mäkinen, K.K. Bennett, C.A., Hujoel, P.P., Isokangas, P.J., Isotupa, K.P., Pape, H.R., Jr. and Mäkinen, P.-L Xylitol chewing gums and caries rates: A 40-month cohort study. Journal of Dental Research. 74: DMFS Scores Group Baseline 28 months 28 months Number of minus baseline subjects No gum Sugar gum Sorbitol gum Sorbitol/xylitol gum 3: Xylitol/sorbitol gum 3: Xylitol stick gum, 3/day Xylitol stick gum, 5/day Xylitol pellet gum, 3/day Xylitol pellet gum, 5/day DMFS scores refer to the number of decayed, missing or filled surfaces of teeth. The DMFS scores show changes in the caries index over a 28-month follow-up period. Positive scores mean an increase and negative scores a decrease in the incidence of caries. Turku University, Institute of Dentistry.

8 Mother-child study: Mothers xylitol chewing gum consumption protects their children from dental caries Eva Söderling The mother-child study started in the early 90 s is the first clinical study on the effect of the use of xylitol by mothers on the colonisation of their children with mutans streptococci and subsequent dental health. The study was designed and carried out by doctors Eva Söderling, docent at the University of Turku, Institute of Dentistry, and Dr. Pauli Isokangas of the Health Care Centre in Ylivieska The study confirmed that the xylitol consumption of the mothers reduced the mutans-transmission 5-fold as compared to the control group receiving f-varnish treatments. Xylitol both reduces the numbers of mutans streptococci as well their transmission properties, which is proposed to explain the results. Dental caries is an infectious disease The earlier the primary teeth are colonised with mutans streptococci, the higher the risk of future caries. The risk of colonisation is highest in children aged about two years. It is usually the mother who inadvertently passes the infection to the child. Frequent saliva contacts through food-tasting or pacifier- cleaning are the most likely routes of passing the infection from mother to child. Mothers used xylitol gum daily for two years The joint project of the Institute of Dentistry, University of Turku and the Ylivieska Health Care Centre started in the early 90 s. The aim of the study was to explore whether mothers habitual xylitol consumption could prevent the mother-child transmission of mutans streptococci, and how the result would be reflected in caries occurrence in the children. Altogether 195 pregnant women with high salivary mutans streptococci levels were invited to the study. In the xylitol group, the mothers chewed xylitol chewing gum approximately four times a day for about two years. The use of the xylitol gum was started before the first primary teeth erupted to ensure that the xylitol-effect on the oral flora was established. In the two control groups, the mothers received either fluoride (F; no effect on transmission of mutans streptococci) or chlorhexidine (CHX; supposed to reduce transmission of mutans streptococci) varnis applications, 6, 12 and 18 months after delivery. All interventions discontinued when the child was two years old. Both saliva and plaque samples were collected from the mothers and their children during the study. The mutans streptococci levels of the samples were determined using both plate culturing and a strip test. Xylitol chewing gum efficiently prevented the transmission of mutans streptococci At two years of age 169 mother-child pairs participated in the study. In the Xylitol group only 10 % (see graphic) of the children became colonised with mutans streptococci, even though the salivary bacteria levels of their mothers were not reduced during the xylitol consumption period. The researchers emphasise that xylitol did thus not reduce the children s colonisation by reducing that of their mothers, but rather by affecting the transmission properties of mutans streptococci. The first two years in a child s life are the most important in caries prevention. The study results indicate that, in future, intervention against colonisation of mutans streptococci with xylitol supplements/contributes to traditional caries prevention methods concentrating on increasing the resistance of the teeth. References Söderling E, Isokangas P, Pienihäkkinen K, Tenovuo J. Influence of Maternal Xylitol Consumption on Acquisition of Mutans Streptococci by Infants. J Dent Res, 79: , 2000 References: Isokangas P, Söderling E, Pienihäkkinen K, Alanen P. Occurrence of Dental Decay in Children after Maternal Consumption of Xylitol Chewing Gum, a Follow-up from 0 to 5 Years of Age. J Dent Res, 79 (11): , 2000.

9 In the Xylitol group, only 10% of the children became colonised with Streptococcus mutans. The corresponding results in the control groups were: In the F-varnish group, the colonisation percentage was 49% and, in the CHX group, 29%.

10 The six-year study in Estonia: Xylitol pastilles effectively prevent dental caries Pentti Alanen Several Finnish and international long-term clinical studies have demonstrated that the regular use of xylitol chewing gum helps in caries prevention. The field study in Estonia, which commenced in 1994, is the first study on the effects of the use of xylitol pastilles on dental caries among children. The results of the study show that regular use of xylitol pastilles did reduce caries occurrence by 50% compared to the control group. The Estonian field study was headed by Dr. Pentti Alanen, Professor at the University of Turku, Institute of Dentistry, and Dr. Pauli Isokangas of the Health Care Centre in Ylivieska. The six-year study in Estonia examined the effectiveness of 100% xylitol chewing gum and xylitol pastilles in caries prevention. School distribution Altogether 740 children from 12 schools in the regions of Tallinn and Tartu took part in the study. Most of the children were born in It was estimated that the selected schools should give an overview of the condition of children s teeth in Estonia. Caries prevalence in the study groups ranged from low to average and high. After a clinical examination at the beginning of the field study, the 12 schools were divided into four groups: a control group, which received no xylitol, a xylitol chewing gum group and two xylitol pastille groups. Each group included all levels of caries prevalence; low, average and high. The study used 100% xylitol-sweetened chewing gum and two different xylitol- sweetened pastilles, all provided by Leaf. The study was blinded between the two pastilles. The daily xylitol dosage was five grammes, consisting of six xylitol gum pellets or eight pastilles. The children were given xylitol three times during the school day. On weekends and during the three month summer break, xylitol was not provided. The children s teeth were examined annually, and caries was registered at three levels. The researchers were blinded in

11 the clinical examination, and did not know what product the groups had used. In each annual examination, children were examined by both researchers in order to account for variations in caries registrations between the researchers. Significant caries reduction After two years use, caries reduction in all xylitol groups was approximately 50% compared with the control group. (see graphic) In the study, xylitol was used only on schooldays, approximately 200 days a year. Despite the three-month summer holiday, the prevention effect achieved was as good as in previous xylitol studies, where xylitol for the most part had been used on a daily basis. The study proved that when xylitol is used regularly for a sufficient period, even a three-month break did not reduce its effect. References Alanen P. Isokangas P, Gutmann K: Xylitol Candies in caries prevention: results of a field study in Estonian children. Community Dent Oral Epidemiol 2000; 28: After two years use, caries reduction in xylitol groups was approximately 50% compared with the control group. Endorsements by dental professionals Encouraging endorsements by various health organisations and professional dental associations have been made, helping clinicians, health authorities and consumers to comprehend the utility value of xylitol in caries prevention. The first professional endorsement for a xylitol chewing gum product was awarded to Leaf Finland by the Finnish Dental Association in The Swedish Dental Association s endorsement 1990 The Norwegian Dental Association s endorsement 1991 The Icelandic Dental Association s endorsement 1993 The British Dental Health Foundation s endorsement 1995 The Estonian Dental Association s endorsement 1997 In Switzerland, Leaf xylitol products were granted the Tooth- Friendly label by dental professionals More information: Osallistumisohjeet löytyvät osoitteessa

12 contacts: Leaf Suomi Oy P.O. Box TURKU Finland Tel.: Layout: Viestintätoimisto Jokiranta Oy / Tuuli Holopainen Printed by Painoprisma Oy 2006