No abstract

The objective of this study was to study the prevalence, characteristics and predisposing factors of tension-type headache in children. An unselected population-based questionnaire study was carried out in 1409 Finnish schoolchildren aged 12 years. Of them, 1135 (81%) returned an acceptably completed questionnaire. The prevalence of episodic tension-type headache in children was 12% (138 of 1135). Children with episodic tension-type headache also often reported characteristics of pain typical for migraine. Children with frequent and persistent episodic tension-type headache reported stabbing and severe occipital pain, phonophobia and abdominal pain significantly more often than children with infrequent episodic tension-type headache. Neck-shoulder symptoms, symptoms of depression and oromandibular dysfunction were each independently associated with episodic tension-type headache. The father's occupation of a lower-level white-collar worker put the child at a four-fold risk for episodic tension-type headache. We conclude that episodic tension-type headache is as common as migraine in children. It can be associated with depression, oromandibular dysfunction and muscular stress. Especially children with frequent and persistent episodic tension-type headache report characteristics of pain typical for migraine.

All field studies have unequivocally reported significant reductions in dental caries occurrence associated with the use of chewing gum containing xylitol. No other xylitol products besides chewing gum have so far been tested in field trials. A 5-year follow-up study with 2- or 3-year xylitol consumption periods began in Estonia in 1994 with 740 10-year-old children in 12 schools at baseline examinations. For the study, 3 clusters each including 3-5 schools were formed on the basis of baseline caries experience. The products were used under the supervision of the teachers 3 times per day during school days but not during weekends or during the 3-month summer holiday. The daily dose of xylitol was 5 g in all groups. The children were examined every year in September by two experienced clinicians. Dental caries was recorded according to WHO criteria. After 3 years, all xylitol groups showed a highly significant 35%-60% reduction in caries incident, compared with the corresponding control groups. The differences between candies, between candies and chewing gum, and between 2- and 3-year users in the xylitol groups were non-systematic, indicating no trends between the groups. The results suggest that not only xylitol chewing gum but also xylitol candies are effective in caries prevention, and that a school-based delivery system seems to offer a practical way to distribute and control the use of the xylitol products.

Studies have shown that prevention of mutans streptococci (MS) colonization in early childhood can lead to prevention of dental decay. In the microbiological part of the present study in Ylivieska, Finland, with 195 mothers with high salivary MS levels, regular maternal use of xylitol chewing gum resulted in a statistically significant reduction in MS colonization in their children's teeth at the age of 2 years compared with teeth in children whose mothers received fluoride or chlorhexidine varnish treatment. The children did not chew gum or receive varnish treatments. For the present study, the children were examined annually for caries occurrence by experienced clinicians who did not know whether the children were colonized with MS. Regardless of the maternal prevention group, the presence of MS colonization in children at the age of 2 years was significantly related to each child's age at the first caries attack in the primary dentition. In children at the age of 5 years, the dentinal caries (dmf) in the xylitol group was reduced by about 70% as compared with that in the fluoride or chlorhexidine group. We conclude that maternal use of xylitol chewing gum can prevent dental caries in their children by prohibiting the transmission of MS from mother to child.

The number of totally edentulous working-age persons is rapidly decreasing in Finland. Edentulism was strongly associated with birth cohorts and is apparently accumulating in a diminishing group of people. Relevant factors that were strongly associated with edentulousness did not vary considerably between the study years.

Occlusal treatments (occlusal splints and occlusal adjustment) are controversial but widely used treatment methods for temporomandibular disorders (TMD). To investigate whether studies are in agreement with current clinical practices, a systematic review of randomized controlled trials (RCTs) of occlusal treatment studies from the period 1966 to March 1999 was undertaken. Eighteen studies met the inclusion criteria, 14 on splint therapy, and 4 on occlusal adjustment. The trials were scored using the quality scale presented by Antczak et al., 1986a (A.A. Antczak, J. Tang, T.C. Chalmers, Quality assessment of randomized control trials in dental research. I. Methods, J. Periodontal Res. 1986a;21:305-314). The overall quality of the trials was fairly low, the mean quality score was 0.43/1.00 (range 0.12-0.78). The most obvious methodological shortcomings were inadequate blinding, small sample sizes, short follow-up times, great diversity of outcome measures and numerous control treatments, some of unknown effectiveness. Splint therapy was found superior to 3, and comparable to 12 control treatments, and superior or comparable to 4 passive controls, respectively. Occlusal adjustment was found comparable to 2 and inferior to one control treatment and comparable to passive control in one study. Because of the methodological problems, only suggestive conclusions can be drawn. The use of occlusal splints may be of some benefit in the treatment of TMD. Evidence for the use of occlusal adjustment is lacking. There is an obvious need for well designed controlled studies to analyse the current clinical practices.

Xylitol is effective as a noncariogenic or even cariostatic sugar substitute. Habitual xylitol consumption appears to select for mutans streptococci (MS) which shed easily into saliva from plaque. We have earlier shown that habitual xylitol consumption of mothers was associated with a statistically significant reduction in the probability of mother–child transmission of MS assessed at 2 years of age. The aim of the present study was to assess the children’s MS counts 1 and 4 years after the maternal xylitol consumption had been discontinued. At baseline, during pregnancy, all mothers (n = 195) showed high salivary levels of MS. The mothers were randomly assigned to xylitol, fluoride (F) and chlorhexidine (CHX) groups. In the xylitol group, the mothers chewed xylitol–sweetened gum, for 21 months, starting 3 months after delivery. In the two control groups, the mothers received CHX or F varnish treatments at 6, 12 and 18 months after delivery. At the 2–year examination, 169 mother–child pairs participated. At the 3–year and 6–year examinations, there were 159 and 147 children in the study, respectively. For children’s MS analyses, visible plaque was collected using toothpicks at the age of 3 and paraffin–stimulated saliva at the age of 6. The persons involved in the collection and analysis of the microbiological samples were blinded as to the study design and group. Both the plaque and salivary MS were cultured on Mitis salivarius agars containing bacitracin. In all groups, the colonization percentages increased during the follow–up. At the 3–year examination, the children’s risk of having MS colonization was 2.3–fold in the F group (95% CI 1.3–4.2) compared to the xylitol group. This difference was statistically significant. Even at 6 years of age, the salivary MS levels were significantly lower in the xylitol group than in the other groups (ANOVA, p<0.001). In conclusion, the earlier demonstrated, xylitol–associated reduction in the probability of mother–child transmission of MS was still found in the children’s MS counts at the age of 3 and 6 years.

Associations between fluctuation of treatment need for temporomandibular disorders (TMD) and age, gender, stress, and diagnostic subgrouping were analyzed in a 2-year follow-up of 391 subjects. All the studied factors were significantly associated with the treatment need for TMD at all examinations. The diagnostic subgroup (TMD arthro, TMD myo, TMD comb, or non-classified) at base line was significantly associated with the fluctuation of the treatment need for TMD also during the follow-up, but age, gender, and stress score were not. In the subgroup needing active treatment for TMD at least once during the follow-up (n = 65), the stress score did not show statistically significant covariation with the treatment need. The diagnostic subgrouping of these 65 subjects at the second and third examination at 12-month intervals did not show any association with the subgrouping at base line or with any studied variable. Detailed descriptive diagnostics may serve well in treatment planning but do not necessarily help us in understanding the nature of TMD.