Institute of Dentistry, University of Turku, Turku, Finland Prevention of mother-child transmission of mutans streptococci with xylitol Eva Söderling Institute of Dentistry, University of Turku, Turku, Finland

Contents Xylitol and dental caries Mechanisms of action of xylitol Mother-child transmission of mutans streptococci Mother-child study: study design and results

Diet and dental caries A healthy diet as such is no threat to teeth Constant snacking is a risk to dental health!

Diet and dental caries… Sugarfree products are useful in improving poor snacking habits Xylitol is the most beneficial sugar substitute – suitable for self-care!

Xylitol/clinical studies Xylitol is most effective in the caries prevention of eruptive teeth (Ylivieska 1988, Belize 1996, Estonia 2000) The ”therapeutic” effects of xylitol appear only in habitual use and with high enough frequencies/doses

Estonian xylitol study (Alanen et al. 2000)

Xylitol adds to caries prevention obtained with fluorides, advice on diet and oral hygiene

Contents Xylitol and dental caries Mechanisms of action of xylitol Mother-child transmission of mutans streptococci Mother-child study: study design and results

Xylitol: a 5-carbon polyol Xylitol is found in nature; fruits, berries... Sweetness equal to sucrose Natural component of the human metabolic pathways

Mechanisms of action No acid production Reduces plaque by suppressing formation of adhesive macromolecules, especially glucans Selects for less virulent mutans streptococci (oral flora?) Xylitol:C5

No acid production from xylitol No acid production in plaque even after long-term consumption Creates conditions favouring remineralisation specific effects on remineralisation? Xylitol:C5

No acid production from xylitol

No acid production from xylitol

The amount of plaque Xylitol reduces plaque ”Xylitol-plaque” shows low adhesiveness to the teeth, xylitol makes plaque easier to brush off Xylitol suppresses formation of adhesive macromolecules, especially glucans

Xylitol reduces plaque

Xylitol reduces plaque formation

Xylitol chewing gum does not replace toothbrushing

Mutans streptococci Xylitol selectively suppresses mutans streptococci The effect on mutans streptococci is transient Xylitol selects for less virulent mutans streptococci

Xylitol inhibits growth of mutans streptococci

Effect of xylitol pulsing on oral streptococci S.milleri S.mutans ADJ, 1991,36,213-5

Xylitol selects for mutans streptococci not inhibited by xylitol Naturally occuring ms which do not form xylitol-5-P from xylitol can ”ignore” xylitol These Xr cells form a small percentage of the ms if no xylitol is consumed During regular xylitol consumption the Xr ms can multiply normally while ms inhibited by xylitol (Xs cells) decrease Xr less virulent than Xs??

Effect of habitual xylitol consumption on plaque vs Effect of habitual xylitol consumption on plaque vs. saliva mutans streptococci levels Log CFU

Xylitol makes mutans streptococci to shed more easily to the saliva

Contents Xylitol and dental caries Mechanisms of action of xylitol Mother-child transmission of mutans streptococci Mother-child study: study design and results

S.mutans infection in infants S. Mutans infection in infants with and without oral development nodules (ODN). N children with nodules = 103, N without nodules = 85. Wan et al. JDR 2001.

The window of infectivity for mutans streptococci

The earlier the mutans streptococci are colonised, the higher is the risk for caries

Transmission of mutans streptococci The mother (infecting person) has high salivary mutans streptococci counts Several daily saliva contacts between the child and the mother must take place

Reducing mutans streptococci in the mother during eruption of primary teeth: Reduces on long-term basis the the mother-child transmission of mutans streptococci Influences beneficially the future caries experience of the child

Methods to prevent the acquisition of mutans streptococci Information on mother-child transmission of ms, advice on diet and oral hygiene Chemical methods (chlorhexidine) Xylitol

Contents Xylitol and dental caries Mechanisms of action of xylitol Mother-child transmission of mutans streptococci Mother-child study: study design and results

Mother-child study Eva Söderling and Pauli Isokangas Institute of Dentistry, Turku Ylivieska Health Centre, Ylivieska

Subjects At baseline 195 mothers with high salivary ms counts 2-year examination: 169 mother-child pairs 6-year examination: 147 children

Study groups Xylitol group: xylitol chewing gum (65%) appr.4 times a day Fluoride (F; control) group: fluoride varnish (2.26%) treatments 2 times a year Chlorhexidine (CHX) group: CHX varnish (40%) treatments 2 times a year All interventions discontinued when the child was 2 years old

Xylitol chewing gum

CHX and F varnishes

Study design Child 3 months: xylitol consumption starts in Xylitol group Biannually: F or CHX varnish treatments in the F and CHX groups Child 2 years: Xyl/F/CHX interventions discontinue Annual follow-up of dental health Microbiological follow-up

Microbiological methods Saliva/mothers and plaque/children annually until the 3-year examination Saliva/children at the 6-year examination Plate culturing on MSB agar of both salivary and plaque mutans streptococci

Results

Mutans streptococci of the mothers: 7 . 5 6 4 P r e g n a c y 1 2 A o f h i l d ( s ) F C H X High salivary mutans streptococci counts in all groups throughout the study No differences between the study groups

Mother-child transmission of mutans streptococci At two years of age, the children in the Xylitol group showed significantly less ms colonisation as compared to the control groups At six-year of age, the Xylitol group still showed the lowest ms counts

Children showing mutans streptococci colonisation (%)

Childrens salivary mutans streptococci counts at 6 years Söderling et al.,2001

The results of plate culturing of mutans streptococci and the chairside SM Strip mutans test were in good agreement

Dental health The differences between the groups found in the early ms colonisation (2 years) were reflected in the caries occurence At the age of 5 years the need of restorative treatment was 71-74% lower in the Xylitol group as compared to the F and CHX groups CHX was not effective in the study design used

Results of the mother-child study have been confirmed by an independent, also federally funded study from Sweden (unpublished)

Xylitol recommendations:

Recommended target groups Children with erupting teeth Subjects with high caries risk Caries-active individuals Elderly dentate subjects Patients with xerostomia Mothers of infants

Recommended intake of xylitol: forms and frequency Chewing gums and lozenges give maximal oral retention and contain no components ”disturbing” the effects of xylitol Products with a high xylitol concentration recommendable For optimal preventive effects 3-5 daily intakes, preferably after each meal

Recommended intake of xylitol: chewing gum Chewing until the sweet taste disappears (appr. 5 min) Children: one chewing gum pellet 3-5 times a day Adults: two chewing gum pellets 3-5 times a day

Thank you! Kam-Sa-Ham-Ni-Da! Kiitos! Institute of Dentistry, Turku