The Caries Experience in Child and Youth Oral Health Care in Denmark from 1972-2022. A Narrative Interpretation of Success

  

    
 
    
1 point
    
2    points 
  
  

    
Childs/parent’s cooperation (risk indicator)
    
God
    
Bad
  
  

    
Caries in progression generally (diagnosis)
    
No
    
Yes
  
  

    
Eruption stage of permanent molars (risk factor)
    
Full occlusion
    
Partial occlusion
  
  

    
Caries in progression occlusally on the erupting    molars (diagnosis)
    
No
    
Yes
  

Table 6B: The criteria for use for the interval planning.

The interval length was determined from the sum of points in Table 6B. One month (8 points), 2 months (7 points), 3 months (6 points), 4 months (5 points) and 6 months or more (4 points). In 1988, impact targets were set for 15- and 18-yr-olds at the dawn of the new millennium, i.e. 12 years after implementation. Impact targets for 15-yr-olds were an average DMFS<1.5 and >2/3 should have a DMFS=0. For the 18-yr-olds, the impact target was an average DMFS<2 and > 50% of the 18-yr-olds should have a DMFS=0. These targets were met in 1999 [35], when the average DMFS in 15-yr-olds in Nexoe municipal dentistry was 0.88 and 71% had a DMFS=0.For the 18-yr-olds, the average DMFS=1.23 and 55% had a DMFS=0.

The Odder model

The Odder model [37], which was implemented in Odder municipal oral health care (PCM) the mid-2005 to 2006, operated with virtually the same risk parameters as in the Nexoe method, but with slightly longer intervals between calls. In contrast to the Nexoe method, the Odder model succeeded in expanding cooperation with the municipality within general health and a health coordinator was appointed. The focus of the health plan was the first 4 years on diet and physical activity. For example, there was zero sugar tolerance in kindergartens and schools.

The Odder model was also distinguished by the dentists being team leaders, while the dental hygienists were key people in examinations and risk assessment and the dental assistants took care of controls and preventive measures. In line with the Nexoe method, the Odder model achieved a large reduction in DMFS, e.g. average DMFS of 15-yr-olds in 2002 in Odder municipality was approx. 3, which fell to <1 in 2012.

Discussion

Figures 2-3 show that the caries experience expressed by the defs/DMF-S indices has decreased significantly among children and adolescents in parallel with the establishment of first the municipal child oral health care scheme in 1972 later replaced by Child and Youth Oral Health Care scheme. Using cross-sectional data, there is a decrease of >85% in average defs on 7 yr-olds from 1972 /73 to 20022 and >90% in average DMFS on 15-yr-olds from 1980/81 to 2022. Similarly, we can see a significant increase in the number of 7- and 15-year-olds with a defs=0/DMFS=0. About 70% of 15-yr-olds had a DMFS=0 in 2022. Data from the Danish Health Authority shows that approximately 20% of the 30% had a DMFS=1-2 and 6% had a DMFS= 3-4. This means that less than 5% had a DMFS of >4. At cohort level (a,b,c,d, Figure 2) and (A-F, Figure 3), there is also a marked reduction in defs/DMFS increment, expressed through the decreasing slopes of the lines towards 2022. The inter-municipal variation in child and adolescents' caries experience, which has been significant over the years [38], has been significantly reduced, at least if you look at data from 2022 (Figure 4), where 94 out of 98 municipalities reported that DMFS=0 in 15-yr-olds was between 60- and 80%. We have only used standard deviations on average defs/DMFS data in this article in the years 1972/73 (for 7-yr-olds) and in 2022 for both 7- and 15-yr olds. This is because standard deviations only became part of SCOR from the year 2000. Standard deviations for 7-yr olds in 1972/73 are due to a special study, conducted by Helm [3].

Data also show that the 4 so-called practice municipalities (where the child and youth oral health care was delivered by Private Practices (PPM’s) over the years) they have achieved the same success in terms of lowering the caries experiences as the PCM’s. In 2019, just before the onset of the COVID-19 pandemic, defs=0 in the 7-yr-olds was 78.8% in the PPM’s (n=551) against 72.8% in the clinic municipalities (n=46645) and for the 15-yr-olds, the figures were 64.7% (n=621) in the PPM’s against 66.8% in the PCM’s (n=48399) [30]. Here it is important to emphasize that dentists and dental hygienists working in the PPM’S must work according to the same regulations as in the PCM’s, including reporting to the SCOR system and perform outreaching (have to contact and treat the children in the municipality) dentistry.

In this article, we have tried to identify initiatives that have played a major role in the improvements achieved over the 50 years and to show that clinical data from municipal dentistry have been able to confirm this (9,13-14,18-20,22-25,27,29,31-39).

As can be seen from Figure 2 and 3, the major significant reduction in defs occurred in the primary teeth of the 7-yr-olds from 1972/73 until 1992 (reduction~64%) and for DMFS in the 15-yr-olds from 1980/81 until 2000 (reduction~73%). From literature review, it can reasonably be documented that the following 7 initiatives have had a major impact on the large reduction in defs/DMFS in the period 1972/73 and up to the turn of the millennium.

Establishment of Oral Health Care for School Children in 1972 with subsequent dentistry for 0-6-yr-olds and expansion with 16- and 17yr-olds (Child and Youth Oral Health Care) so that dentistry involved children and adolescents from 0-18 years in 1988.

Continuous focus on brushing twice daily with fluoride-containing toothpaste as well as instruction and training in better plaque removal.

The use of fluoride rinses in schools (primarily 0.2%NaF solution every 14 days)

Local fluoride treatment e.g. with Duraphat varnish (22,800 ppm F) or 2% NaF solutions (9000 ppm F)

Widespread use and subsequent extended indication range for the use of fissure sealing

Changes in the criteria and timing of filling therapy

Working risk related, including viewing the eruption period of the permanent molar teeth as a risk factor

Regarding toothbrush instructions, Kirkegaard [39] conducted a review

of clinical studies back in 1981 and concluded "that brushing may contribute to some extent to a reduction in caries activity, especially on easily accessible tooth surfaces. However, it is difficult to provide completely convincing evidence". Data from SCOR from 1972/73 to 1986/87 showed a gradual improvement in plaque index among children and adolescents. Later clinical studies also showed that the plaque index has become even very low in child and youth oral health care in Denmark [17], so the resources, which the staff in child and youth oral health care have used and still use in this area, have not been in vain.

Fluoride rinses were phased out in the late 80s, when clinical studies showed that local application of fluoride, such as Duraphat varnish, was as effective as rinsing. However, Duraphat varnish was more expensive to use than fluoride rinses [18] and radiological data from Værløse also showed that fluoride rinses were more effective than Duraphat varnish [20]. The first author of this article therefore opens up for a discussion of whether a cost-effective method such as fluoride rinsing [18,20] should be phased out in general in Child and youth Oral Health Care in Denmark. An alternative could be that oral health care in the individual municipalities should instead have considered continuing with rinsing for children at risk and during risk dental ages, for example from 5-6 years of age to the permanent 1st molar teeth were fully erupted. This is to reduce filling-requiring caries on the most caries-prevalent surfaces in both dentitions, namely approximally between the primary molars and occlusally/bucally/palatinally on the 1st permanent molars [25,30]. In municipalities with a fluoride content below e.g. 0.3 ppm in the water supply, it would be obvious to discuss such an effort even today and be highly relevant to the many refugee children who have a high caries treatment need. The counter-argument (from the 2nd and 3rd authors) is that the children and adolescents who needed to rinse would be exposed to a possible stigma. It is more relevant today to organize local oral health care in accordance with what we know about how caries can be controlled [35,36,37, 40].

Although 2/3 of the observed reduction in defs/DMFS in this article expressed in 7- and 15-yr-olds occurred before the turn of the millennium, caries experience continued to decline until 2022 (Figure 2,3).

Possibly prompted by Bratthall and colleagues from Malmö and their work with the Cariogram [41], a computer-based caries risk programme, caries risk assessment became a popular tool in the 1990s and onwards in Child and Youth Oral Health Care Scheme. The risk assessment of caries was considered as the basis for decisions on preventive and conservation treatment, as well as for determining an appropriate call interval. The Nexoe method (Table 6B) and the Odder model used caries risk assessment on children and adolescents, and this measure helped to achieve the results described above. As far as is known, the Nexoe method and the Odder model are the only two programmes with data over a 10 year period or longer, which are described in detail both nationally and internationally [35,36,37]. In all the years, there has also been an extensive national as well as international course activity around the two programs.

SEAL treatment, sealing occlusal caries with or without clinical cavity and radiologically identified dentin caries limited to the outermost 1/2 part of the distance to the pulp introduced by the Qvist group [29] should also have been an initiative that reduced DMFS. But the Qvist group has proposed that the SEAL treatment be registered with a “4“ on the formular (Figure 1), just like a filling, which is why SEAL-treated teeth cannot be directly read in SCOR. SEAL treatments are convincing evidence that the indications for filling therapy have changed over the 50 years of Child and Youth Oral Health Care in Denmark.

    

    

    Figure 1: Example of form and scores used in the public Dental Health System in Denmark for recording caries. The scores and descriptions are shown to the right. The form illustrates the caries status of a 9-year-old child who has both primary (0) and permanent teeth (1) present. Absence of scores in the boxes indicates that the surface is sound in terms of caries. The child has had tooth 84 extracted (score 6) and restorations on 74 and 75 (score 4). In the permanent teeth, there are restorations (score 4) on the occlusal surface on 16, 26, 36, and on the mesial surface on 26. The occlusal surface on tooth 46 and the palatinal pit on 16 are sealed (score 8). The mesial surface on tooth 46 and buccal pit on 36 have active, cavitated caries lesions (score 1), whereas the palatinal pit on 26 has an initial caries lesion (score 0). Finally, the buccal pit on tooth 46 has an arrested caries lesion (score 9). The total deft/s and DMFT/S are given to the right. The d/D component indicates active caries lesions with cavitation (score 1) requiring restorative treatment: the e/M component indicates teeth extracted due to caries (score 6), and f/F restored tooth/surface (score 4) due to caries. Note that scores 0, 7, 8, and 9 are not a part of the def/DMF index.