Mother-child study

Mothers' xylitol chewing gum use protects their children from dental caries

The mother-child study started in the early 1990's is the first clinical study on the effect of the use of xylitol by mothers on the colonisation of their children with Streptococcus mutans 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 Pauli Isokangas of the Health Care Centre in Ylivieska

The study confirmed that maternal xylitol chewing gum consumption 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 Streptococcus mutans, 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 early 1990's. The aim of the study was to explore whether mothers' habitual xylitol consumption could prevent the mother-child transmission of S. mutans, 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 S. mutans) or chlorhexidine (CHX; supposed to reduce transmission of S. mutans) varnish 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 Streptococcus mutans levels of the samples were determined both using plate culturing and a strip test.

Xylitol gum efficiently prevented the transmission of Streptococcus mutans

169 mother-child pairs, with the child at the age of two, participated in the study. In the xylitol group only 10 % (see table) of the children became colonised with mutans streptococci bacteria, 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 the mutans streptococci.

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 %.

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 mutans streptococci colonisation may lead to better caries prevention than the traditional caries measures 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: 882-887, 2000.

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): 1885-1889, 2000.

 

Follow-up study

 

Mothers' Xylitol Usage Has Long-term Effects on a Child's Dental Health in Primary Teeth

Earlier studies have shown that the composition of the bacterial strain acquired in infancy has an effect on the formation of cavities in teeth. Of oral bacteria, particularly mutans streptococci increase a child's risk of developing cavities. The most common channel of mother-child transmission for these bacteria is saliva.

The doctoral dissertation of Marja-Liisa Laitala, Licentiate in Dentistry, is a follow-up study of an earlier mother-child study that indicated that mother-child transmission of mutans streptococci was reduced fivefold when xylitol was used. Leaf's 100% xylitol chewing gum was used in the mother-child study. Laitala's study examined the dental health in primary teeth of approximately 500 children. The number of dental treatments for these children were monitored from birth until 10 years of age.

Primary teeth can be maintained completely cavity-free for a long period of time by influencing the composition of the bacterial strain transmitted from a mother to her child. The improved health of primary teeth continues up to their falling off. When early formation of cavities in primary teeth is prevented, the number of treatment visits needed for primary teeth fillings decreases, which in turn lowers the dental treatment costs of health centres.

Long-term benefits and cost-effectiveness

The current follow-up study indicated that the benefits of xylitol usage by mothers are long-term and that xylitol usage is also an economically sound option. Infants are spared of toothache and any fear or pain that dental treatment might cause. Filling treatment results in schoolchildren are often better if there have been no treatment procedures in infancy. This way it is possible to save health care resources and reduce health care costs.

Children whose mothers have a great deal of mutans streptococci in their saliva have a high risk of developing cavities. The risk group children, whose mothers used 100% xylitol chewing gum regularly when the child was under two years of age, had their first cavities in primary teeth on average at the age of 8 and 40% less caries. The difference could still be seen at the age of 10.

In comparison, in the teeth of the children with mutans streptococci colonisation, the first cavities started to appear before five years of age. The prevention of mutans streptococci colonisation improved the dental health of children with a high caries risk to the average level of their age group.

The study by Marja-Liisa Laitala shows that making an effort to prevent children's caries by targeting mothers reduces cavity formation in children's teeth for up to ten years. This type of self-treatment through using xylitol does not require substantial resources nor dentist consultations. When children's filling treatment visits decrease, municipalities save money as less resources are needed.

 

Marja-Liisa Laitala: Dental Health in Primary Teeth after Prevention of Mother-Child Transmission of Mutans Streptococci. A Historical Cohort Study on Restorative Visits and Maternal Prevention Costs. Dissertation at the University of Turku 24 September 2010.

The dissertation is published in the electronic publication archive of the University of Turku at https://oa.doria.fi/handle/10024/63589