The aim of this retrospective, data-based 10-year follow-up study was to assess the effect of dental fear treatment in the Clinic for Fearful Dental Patients (CFDP) in the City of Oulu, Finland, on dental attendance in primary health care as indicated by examinations, emergency visits and missed appointments. During the 10-year-follow-up, those who had been referred to dental fear treatment at an early age (< 10 years) or whose dental fear treatment was considered successful in 2006 [20] had more dental examinations than the rest. As for emergency visits and missed appointments, no association with the success of dental fear treatment was discovered. Among those older than 10 years at the baseline and with 5 or less examinations during the follow-up period, even one emergency visit indicates that the preliminary dental fear treatment outcome in 2006 baseline was not successful.
The patient sample was relatively small and patients of only one specialized unit for dental fear treatment were observed. However, the outcome could be monitored for 57% of the originally treated individuals and 93% of those for whom the short-term baseline outcome was investigated in 2006. Heterogeneity in terms of age in the study population can be considered a shortcoming. The biggest difference between a similar study by Berge et al. [12] and the current one is that here, all patients were included despite their physical or mental status or the dental care they needed. In addition, all the dental procedures needed were performed during dental fear treatment, including dental general anaesthesia as well. Considering the challenges in the study population, the 2- and 10-year outcomes seem satisfactory. On the other hand, the follow-up period in this study from early childhood to adolescence or even adulthood was longer compared to many other studies [17, 18]. Participants success of dental fear treatment as a baseline condition was evaluated in 2006 and has not been evaluated in a similar manner later on. So, it is possible, that in some cases the outcome was positive after 2006, but also some positive outcomes may have been negative later on. However, this work aims to find the longterm impact of dental fear treatment. Length of the monitoring period for some of the participants was even longer than 10 years, which can be considered a strength.
The benefit here is a long monitoring period of 10 years; to our knowledge, this is the only study of its kind in a public dental health setting. In earlier studies, patients were monitored for shorter periods [13, 18] or two separate cohorts were compared [21], or dental fear treatment was given by a psychotherapist [11, 16]. It is also common to use surveys in studies of this kind and the response rates tend to be quite low [17, 22]. Patients with severe dental fear may not participate in such surveys if they avoid dental appointments in general [18]. Data based on patient records, not dependent on participation, is a benefit in a study like the present one, where the study population can be monitored with or without attendance. The Finnish Public Dental Services provides reliable longitudinal data for research purposes [23]. The present study population was 152 patients who made up 93% of the population evaluated in 2006 for the success of dental fear treatment with a follow-up period of about 2 years. Most participants were children living at home at the time of the original dental fear treatment (2000–2006) and still lived in Oulu in 2016 (93%) [20]. Because the lack of nationwide welfare databases before year 2017 records of those patients`who have moved to another area or continued their dental care in private dental offices were missing. This is a shortcoming in this database study.
Irregular or non-existent dental attendance because of dental fear is associated with a vicious circle of dental care avoidance, fear and poor oral health [1, 2, 24]. Avoidance causes suffering for individuals, and expenses for them as well as for society [25]. Finnish dental care system recommends examinations according certain intervals, which explains fewer examinations among the youngest participants. Individual intervals should be shorter if a patient has treatment needs or is at high risk i.e. for dental caries. At the referral all patients had a need for dental treatment: 92.6% had cariological problems or needed extractions which may indicate that they are at risk also for deteriorating oral health if not treated regularly. Thus, despite age, they should have had recall periods (examinations), maximum 1 year. It appears that males had more dental examinations than females. Those with a successful baseline condition had more dental examinations than the ones with no success, which can be considered a sign of regular dental attendance among those with preliminary success. This result is in accord with the findings of the review by Wide-Boman et al. [15].
Dental fear, if not addressed, can persist and complicate life over the years. Adolescents are in their sensitive years of life due to physical as well as mental developmental changes and are at risk of anxiety disorders later in life if the fears are not treated [16]. Children under 10 years have not usually reached their adolescence phase with rapid changes in cognitive and psychological development towards adulthood [26], which may affect the outcome of dental fear treatment and this was the cut-off point of the present dichotomization. The small size of the study population hindered comparing several age groups instead of two. Here, those who belonged to the age group of > 10 years at the time of dental fear treatment tended to have more emergency visits than the ones treated at a younger age. This shows that it is more challenging to have a positive effect on the vicious circle after early childhood years. Males tended to have a higher number of emergency visits (> 10) than females, as has been reported in previous literature [27,28,29]. Details of the clinical situation at the baseline were not available but may have caused the difference.
Our previous study indicated that it is beneficial to treat dental fear at a young age, and the same trend is seen here. Preliminary successful baseline outcome of dental fear treatment was specifically associated with optimal number of dental examinations, which can be considered a sign of regular dental attendance among those with preliminary success. This study indicated that there is an association between dental attendance with a low number of examinations with at least one dental emergency visit and not successful preliminary dental fear baseline condition. It is essential to recognize and bring to regular dental care this vulnerable group, whose dental attendance and avoidance can be influenced by fear treatment. Emergency dental care could be a place for recognizing this group by using dental fear forms, for instance. Research is needed on this topic.
The number of missed appointments per se was fairly low in both age groups, but varied a great deal. The proportion of those with more than 10 missed appointments was 5.9% while the proportion among boys was 9.0% and among girls 1.6%. Male sex seems to be associated with avoidance, as also seen in literature [30]. The figures for all missed appointments were higher here than for general population in the City of Oulu, Finland; 3–5% at the time of the study (Statistics, the City of Oulu Finland 2019) and among those having at least one missed appointment in line with a previous study of Tilja et al. on DGA patients [31]. In our study there was a trend that a successful preliminary baseline condition was associated with no missed appointments.
It has been reported that reduction in dental fear measured by surveys does not necessarily correlate with improved dental attendance [17]. Dental fear surveys are essential in detecting, treating and monitoring dental fear in general practice. Here, the preliminary reduction of dental fear was practice-based, based on successful dental attendance in primary health care after dental fear treatment. The present protocol appeared to be beneficial—the preliminary success of dental fear treatment and later dental attendance were associated. Despite the fairly high preliminary success of dental fear treatment, this study population remains a challenge and special attention should be given to regular recalls of fearful patients, especially as most negative dental treatment experiences may lead to the reactivation of dental fear despite positive former experiences [32]. In the future, similar practice-based studies can reveal the patterns of dental attendance, e.g. after successful dental fear treatment.