[Trends in DMF in children and adolescents from 1990 to 2009. Research in a changing context]. / Trends in cariësprevalentie bij kinderen en jongeren van 1990-2009. Een onderzoek in een veranderende context.

Since 1987, research has very frequently been carried out in the Netherlands on the oral health of children and adolescents, so-called 'TJZ research'. For an analysis of the trends in caries experience DMF in children and adolescents in the Netherlands, the results of the TJZ research from 1990, 1996, 2005 and 2011 were used. The changing social context and the fact that the age groups studied were different in the different years of survey were taken into account. The TJZ surveys were conducted among 8/9, 14/15 and 20/21-year-olds living in Alphen aan den Rijn, Gouda, Breda and's-Hertogenbosch and consisted of a questionnaire and a clinical oral examination. The results revealed that from 1990 to 2009, depending on age, either a decrease or no significant changes were seen in DMF. However, there is still room for further improvement in oral health in children and adolescents. It is up to the public debate to determine what extent of caries experience is acceptable from a public health perspective.

[Indications for and frequency of intraoral radiographs]. / Indicatie voor en frequentie van intraorale röntgenopnamen.

Radiographs are essential in dental practice today. Due to the exposure of patients to X-rays every radiograph has to be justified. The advantages and disadvantages of risks and diagnostic rewards have to be weighed against one another whenever X-ray imaging is considered. An important factor in this respect is the usefulness (in terms of sensitivity and specificity) of a radiograph and along with that, the monitoring of the quality of the entire process, from positioning the photo up to and including the development or scanning of it. Both for children and adults the indication for taking radiographs must be made on an individual basis. The most important considerations are: caries experience, oral hygiene and nutritional habits and exposure to fluorides. Based on these factors an individual risk assessment can be made and the possible benefit of bitewing radiographs for the dental treatment can be determined. European guidelines give advice on the indications and frequency of radiographs in, among other fields, periodontology, endodontology and implantology.

[Websites of dental practices evaluated]. / Websites van tandheelkundige praktijken langs de meetlat.

In 2013, a dental practice without a website is almost unthinkable. Using a sample of309 dentists drawn from the list of members of the Dutch Dental Association in 2012, a study was carried out to find out whether the dental practice of the general dental practitioner had a website. The content of each website was subsequently inventoried using a questionnaire. Eighty-nine percent of the dental practices had a website. The content of the websites, however, varied enormously. An element such as the professional registration number with a reference to the professional register were absent in 73% of the websites and the date of the most recent update of the website was mentioned only once. The name of the dentist, his or her professional qualification and an email address were missing on respectively 9%, 20% and 9% of the websites. Contracts of the practice with insurance companies were rarely clearly indicated. The websites of many practices would benefit considerably from a significant improvement.

A three-year randomized controlled trial in 6-year-old children on caries-preventive strategies in a general dental practice in the Netherlands.

A parallel-randomized controlled trial on caries-preventive strategies was conducted in a general dental practice with a mixed socioeconomic background patient population. The aim of this study was to test the hypothesis that, compared to regular care consisting of check-ups twice a year with professional fluoride applications and pit and fissure sealants in all permanent molars, a larger caries-preventive effect can be achieved by following a non-operative caries treatment and prevention (NOCTP) strategy or by following, in addition to regular care, an increased number of professional topical fluoride applications (IPFA). A total of 230 children (6.0 years ± 3 months of age) were randomly assigned to the two experimental groups or the control group. After 3 years, 179 participants remained in the study (54 NOCTP, 62 IPFA and 63 control). The children were examined at baseline and at 3 years by the same experienced examiner, who was blinded for the allocation of the children. Caries was scored clinically at the D3 level. Per protocol analysis revealed a mean DMFS increment after 3 years of 0.15 (95% CI -0.05 to 0.35) for NOCTP, 0.34 (95% CI 0.11 to 0.54) for IPFA and 0.47 (95% CI 0.26 to 0.68) for the control group. To account for missing data, multiple imputation was used, after which the mean DMFS increment was 0.11 (95% CI -0.05 to 0.27) for NOCTP, 0.29 (95% CI 0.11 to 0.46) for IPFA and 0.40 (95% CI 0.21 to 0.55) for the control group. Testing the differences with independent samples t test revealed a lower caries increment in the NOCTP group compared to the control group. ANCOVA was used to correct for differences in baseline dmfs, socioeconomic status and perceived dental hygiene burden. The ΔDMFS effect size between the NOCTP and the control group dropped, losing statistical significance (p = 0.06). Although the results in this study are promising, it has yet to be established in a larger study whether NOCTP has the ability to be effective in regular dental practice with a mixed socioeconomic status population.

Trends in oral health in young people in the Netherlands over the past 20 years: a study in a changing context.

OBJECTIVES: From 1 January 2006, the distinction between the health insurance fund and private insurance was abolished and a basic insurance package was agreed for everyone in the Netherlands. Dental treatment for young people below the age of 18 is reimbursed under the terms of this basic package. Dental treatment for adults is not covered in this basic insurance package. Basic principles for nonreimbursing dental care for adults were that any health and financial risks for individual citizens in the future should be acceptable for them with the corollary that the oral health of young adults when they make the switch - from collectively financed care to care to be paid for individually - should be at such a level that the needed oral health care is affordable. To meet this requirement, it is important to have knowledge of the prevalence of oral diseases and trends in oral health in young people from a public health perspective. The aim of this article is to describe trends in caries experience in young people in the Netherlands from 1990 to 2009, taking into account the challenge in methodology concerning this changing social context. METHODS: To describe caries experience in young people, a repeated cross-sectional study design was used. The study consisted of a clinical oral examination and a questionnaire survey. Data were sampled from 8, 14 and 20-year-olds in 1990 and 1996, and 9, 15 and 21-year-olds in 2003 and 2009, living in Alphen a/d Rijn, Gouda, Breda and 's-Hertogenbosch. The DMF index was used for describing caries experience. The trends were studied separately in high and low socioeconomic status (SES) groups. SES was operationalized as the dichotomous variable of educational level of the mother or the adolescent. Multiple imputation was applied to predict the DMFS for missing ages for certain years, which made it possible to test the trends. Linear and logistic regression analyses were used to study the trends through the years. RESULTS: This study showed, according to different age- and SES groups, either declines or no statistically significant changes in caries experience over the last two decades. CONCLUSIONS: No deterioration was shown. However, there is still room for further improvement in oral health in children. Dental professionals and politicians should develop a vision on to what extent caries experience is acceptable in a public health perspective in young people.

[Referral of patients with non-odontogenic oral diseases to an oral and maxillofacial surgeon]. / Verwijzing van patiënten met niet-odontogene mondaandoeningen naar een mond-, kaak- en aangezichtschiurg.

Patients with non-odontogenic oral diseases may be referred to an oral and maxillofacial surgeon by a dentist, a general medical practitioner or a medical specialist. At the department of Oral and Maxillofacial Surgery of a medical centre, a survey involving 96 referred patients with a non-odontogenic oral disease addressed the clinician who was responsible for the referral, the patient characteristics, and the nature and location of the oral disease. From the patients who regularly visited a dentist, 53% were referred by a dentist. From the patients who visited a dentist irregularly, 73% were referred by a general medical practitioner. No significant correlation was found between the nature and location of the non-odontogenic oral disease and the profession of the clinician who was responsible for the referral, with an exception for the tongue, for which a medical specialist was more often responsible for the referral.

Non-participation in a randomized controlled trial: the effect on clinical and non-clinical variables.

Studies reporting clinical and non-clinical parameters of participants and non-participants of clinical trials are scarce. In the available studies non-participants were likely to show less favourable outcomes than participants on both socioeconomic parameters as well as on caries experience. However, the impact of non-participation on the total sample of the research population is not established. In the present study, as part of baseline data collection for a randomized controlled trial on caries-preventive strategies, 346 parents of children 6.0 years (± 3 months) of age were approached to let their child participate. Sixty parents refused, but 56 of them were willing to fill out the same set of questionnaires and to allow their child to be clinically examined once. Parents from participating children had higher socioeconomic status, were more often of autochthonous origin and scored better on knowledge questions than parents of non-participating children. Furthermore, parents of participating children reported a higher willingness to invest, were more likely to hold on to regular meals and their child had lower levels of plaque compared to non-participating children. Surprisingly, the participating children had higher dmfs scores than the non-participating children. Their care index (fs/ds + fs) was higher than that of non-participating children. Based on the findings of this study, the presumption that non-participating children will show less favourable clinical outcomes cannot be supported. Although participants differed from non-participants, they did not differ from the total population. It is suggested that the external validity of a randomized controlled trial on caries-preventive strategies is not necessarily affected by non-participation bias.

Attitudes towards oral health among parents of 6-year-old children at risk of developing caries.

OBJECTIVES: Parental attitudes are likely to play a role in achieving and maintaining a desired level of oral health in children. To be useful in individually delivered caries prevention programmes, parental attitudes should be identified at individual level. Q-methodology has been proved successful in identifying attitudes in a wide range of disciplines but in dentistry Q-studies are scarce. In this study Q-methodology was used to identify parents' prevailing attitudes towards the oral health of their children. METHODS: Thirty-nine parents ranked 37 statements regarding the dental health behaviour they apply to their 6-year-old child. They later explained their rankings during a short interview. In Q-methodology, rather than reporting one average composite attitude and opinion, various combinations of opinions and attitudes concerning these statements are identified using by-person factor analysis. RESULTS: Based on their beliefs, attitudes and cognitions, five categories of parents were found: (i) conscious and responsible, (ii) trivializing and fatalistic, (iii) appearance-driven and open-minded, (iv) knowledgeable but defensive and (v) conscious and concerned. CONCLUSIONS: Q-methodology appears to be a fruitful way to structure the complexity of parents' opinions and attitudes towards their children's dental health. It appears that Q-methodology provides comprehensive clusters of individual attitudes, based on various levels of responses to a wide range of questions. The five identified profiles may be useful in developing tailor-made prevention strategies in caries prevention.

Dental students' part-time jobs in dental practices in the Netherlands.

OBJECTIVE: In the Netherlands, the Individual Health Care Professions Act (IHCP Act) allows dental students, amongst other non-qualified individuals, to work under certain conditions in a dental practice. The aim of the study was to determine how many dental students have part-time employment in dental practice and which professional tasks they carry out. We also asked the dental students their opinion about the IHCP Act. MATERIAL AND METHODS: All the enrolled dental students at the Academic Centre for Dentistry Amsterdam (ACTA) in the Netherlands received a questionnaire by e-mail. Within 1 month, two reminders were sent. RESULTS: The response was 44% (427 students). Of the responding students, 71% had paid employment in addition to their study. Twenty-five per cent of all students worked in a dental practice, usually 8 h a week. Study year and age were positively related to working part-time in dental practice. Activities frequently performed were providing chair side assistance, giving oral hygiene instruction, fluoride applications, scaling and root planning. The self-reported knowledge about the IHCP Act was positively related to study year and working in a dental practice. Hardly any information about the requirements of the IHCP Act with regard to delegation of tasks was provided by the employer. CONCLUSION: Many Dutch dental students work in a dental practice, taking over a variety of tasks. Although the self-reported knowledge about the IHCP Act was relatively high, many dental students expressed the need for more detailed information about the legal aspects of their tasks.

Dental hygiene students' part-time jobs in dental practices in the Netherlands.

OBJECTIVE: Many students have paid employment while studying. In the Netherlands, the Individual Health Care Professions Act (IHCP Act) allows dental hygiene students to work under certain conditions in a dental practice. The aim of the study was to determine how many dental hygiene students have part-time job employment in dental practice and which professional tasks they carry out. We also asked the dental hygiene students their opinion of the IHCP Act. METHODS: All the enrolled dental hygiene students (n = 341) at a School of Health in the Netherlands received a questionnaire by email. RESULTS: The response was 52% (176 students). Of the responding students, 75% had paid employment in addition to their study. A proportion of the students (35%) worked in a dental practice. The median number of hours worked per week was eight. Study year, age and prior education were positively related to working part-time in dental practice. Activities frequently performed were giving oral hygiene instruction, fluoride applications, scaling and root planning, providing chair side assistance and giving local anaesthesia. Although the self-reported knowledge about the IHCP Act was high, almost half of the students expressed the need for more detailed legal information. CONCLUSIONS: Many dental hygiene students work in a dental practice, taking over a number of tasks usually performed by the dentist. More information in the dental hygiene curriculum about the requirements of the IHCP Act seems desirable.

[Secular trends of caries prevalence among 6 and 12 year-old youths in the Netherlands]. / Trends in de prevalentie van cariës bij de 6- en 12-jarige jeugd in Nederland.

In order to gain insight into the development of caries prevalence and caries experience among Dutch youth, a meta-analysis was carried out on epidemiological caries data collected in 5 and 6 and 11 and 12 year-olds between 1980 and 2009. From the present analysis it appears that after the mid-1980's a halt occurred in the decline of caries experience in the primary dentition among 5 and 6 year-olds. At the same time, the percentage of children with a caries-free primary dentition who were covered by public health insurance or participated in institutions for youth dental care decreased. Among 11 to 12 year-olds there is no indication that the prevalence of caries in the permanent dentition has changed. Considering the high percentage of 12 year-olds with a caries-free permanent dentition, an additional improvement in oral health for this age-group will be difficult to achieve. The average restorative index of the primary dentition in 5-6 year-old children covered by public health insurance and children in The Hague appears not to have changed dramatically in the last 15 years.

[Study on delegation. Dental activities by students in dental practices]. / Studeren op delegeren. Tandheelkundige werkzaamheden door studenten in de tandheelkundige praktijk.

Some dental students in the Netherlands have a job in a dental practice next to their study, as the Individual Health Care Professions Act (introduced in 1997 as Law BIG) allows. The aim of the study was to determine how many dental students of the Academie Centre for Dentistry Amsterdam actually work in a dental practice, which kinds of dental activities they perform and whether these meet the requirements of the Act mentioned before. All dental students (n = 947) received a questionnaire by e-mail. The response was 44% (427 students). Of these students, 71% had a job next to their study; 25% worked in a dental practice. Study progress and age were positively correlated with working in a dental practice. Their activities mainly involved chair assistance, giving brushing instructions and fluoride applications, and dental cleaning. These students asseemed that they were better informed about the Individual Health Care Professions Act than other students. The source of this information was not, however, the practice where they worked. It was evident, moreover, that they felt the need for more information concerning the delegation of restricted dental activities.

[The restorative care index in children 1. Factors concerning the child]. / De restauratieve verzorgingsgraad bij de jeugd 1. Patiëntgebonden factoren.

In 2007 a study was undertaken of the restorative care index of the teeth of children under the age of 18. The aim of this study was to gain insight into the factors associated with the restorative care index in children. Factors investigated were (post-) brushing, inspection frequency, sweets-consumption frequency, socio-economic status and treatment or lack thereof by a general practitioner or dentist who works in a clinic for child health care. This study made use of statistics assembled for an earlier study of children formerly covered by public health insurance in the municipality of The Hague and research carried out at child dental clinics. Socio-economic status and the level of oral care were correlated with dental quality. No patient-bound factors were significantly correlated with the level of care. There was however a positive correlation between the'type' of dentist (family dentist or dentist associated with a clinic for child dental care) and the chance of curative treatment (in the case of developing caries).

Oral and salivary changes in patients with end stage renal disease (ESRD): a two year follow-up study.

OBJECTIVES: To compare oral health, salivary flow rate, xerostomia and thirst in end stage renal disease (ESRD) patients remaining on dialysis treatment and after renal transplantation. DESIGN: Longitudinal observation. SETTING: ESRD patients recruited from dialysis centres in Amsterdam, The Hague and Utrecht, The Netherlands. METHOD: At baseline and after two years, salivary flow rates, xerostomia and thirst were determined in 43 ESRD patients. The number of decayed missing filled teeth/surfaces (DMFT/DMFS) was recorded, and periodontal status assessed. RESULTS: After renal transplantation (n = 20), the salivary flow rate increased significantly from UWS = 0.30 +/- 0.21 ml/min to 0.44 +/- 0.29 ml/min (p <0.001) and the level of xerostomia and thirst decreased. After two years, the percentage of bleeding on probing in dialysis patients (n = 23) decreased from 29.5 +/- 25.4% to 10.3 +/- 12.3%, (p <0.05). No differences in DMFT and DMFS were observed between dialysis and renal transplant patients. CONCLUSIONS: DMFT, dental plaque, gingival bleeding and periodontal indices did not change remarkably after two years, comparing dialysis and renal transplant patients. Renal transplantation enhances salivary flow and decreases symptoms of xerostomia and thirst, and hence enhances the potential to improve the quality of life of affected individuals.

[Trends in oral healthcare. Caries prevalence and frequency of visits to the dentist for checkups]. / Trends in mondgezondheid. Cariësprevalentie en frequentie van controlebezoek aan de tandarts.

In 2003 the project 'Changes in oral health and preventive behaviour'was carried out for the sixth time in succession in The Netherlands. Children and adolescents were asked to fill out a questionnaire and to participate in an oral health examination. Compared to the 1996/1997 results 9-year-olds had a lower incidence of FS and DMFS, 14-year-olds had a higher incidence of DS, and 20-year-olds had a larger number of DS and a smaller number of FS, DMFS and DMFT in 2003. The care index in 2003 was between 48% and 68%. Compared to the 1996/1997 results more 21-year olds visited the dentist annually instead of twice a year. Considering possible consequences of the change in the Dutch health insurance system as of January 2006, such tendencies need careful monitoring.