Abstract
Aims
The aim of this study was to investigate the oral health status of all new recruits and officer cadets entering the New Zealand Defence Force (NZDF) over a one-year period. The second aim was to investigate differences in their clinical status by sociodemographic characteristics, dental visiting patterns, and dental self-care habits. The third aim was to investigate the determinants of their Oral-Health-Related Quality of Life (OHRQoL).
Methods
A cross-sectional study was conducted of recruits entering the NZDF using data from their initial dental examination, posterior bitewing radiographs, orthopantomograph and a socio-dental questionnaire (including Oral Health Impact Profile–14 (OHIP-14)). This data was used to calculate DMFS, DMFT, PSR, third molar eruption and impaction status, and OHRQoL scores.
Results
A total of 874 recruits took part, with an 83.1% participation rate. The majority of the recruits (80.2%) were male, and one in five were Māori. Most of the recruits (88.3%) were aged between 17 and 25 years old. The majority of recruits were in the Army (60.1%), followed by the Navy (28.1%) and the Air Force (11.8%). Two-thirds of recruits reported being routine dental users (visits for check-ups). Over 90% of all the recruits had accessed the State-funded dental care between the ages of 13–18 years. The prevalence of smoking was low at just over one in 20. Three-quarters of recruits brushed their teeth at least twice a day, and just over one in five were regular flossers.
Overall, it was found that the oral health of the recruits and officer cadets was acceptable, but a quarter of all recruits had one or more tooth surfaces with untreated dental caries, and two-thirds had calculus present. Only 30.2% of recruits had no dental caries experience, however, the prevalence of periodontal pocketing was low, at 3.0%. The dental caries data presented in this study shows evidence of the effect of sociodemographic characteristics such as sex, age, ethnicity, and education have on dental caries experience in NZDF recruits. In particular, dental caries experience showed a clear and consistent pattern whereby it was lowest among the youngest group, and greatest in the oldest recruits.
In this study, nearly 90% of recruits had one or more third molars, and nearly 60% had at least one third molar that was unerupted or partially erupted and impacted. Of the mandibular third molars nearly half were unerupted or partially erupted and impacted. The most common type of impaction in mandibular third molars was mesioangular (27.4%), followed by vertical (10.3%), horizontal (9.2%) and then distoangular (1.2%).
The recruits’ mean OHIP-14 score was 7.4 and 18.0% of recruits reported that their oral condition had negatively impacted them in some way “fairly often” or “very often” in the last 12 months, thereby affecting their OHRQoL. Mean OHIP-14 scores were higher for those with greater dental caries experience (especially those with untreated decay or missing teeth due to decay), and older recruits. After controlling for confounders in a negative binomial regression model, OHIP-14 scores were higher for Māori, those who had visited a dental professional in the last two years, and those with untreated decayed teeth, and lowest for those who were routine dental users.
Conclusions
This study is valuable because it reports clinical findings combined with self-reported factors on a sample of young adults from diverse SES and geographical backgrounds in New Zealand. Overall, the oral health of NZDF recruits was acceptable and had vastly better DMFT scores than the 1950s, but a quarter required restorative work and two-thirds needed periodontal treatment. Potential problematic third molars were common necessitating careful assessment (and possible removal) of third molars prior to any operational deployment. Those with poorer oral health status had worse OHRQoL. The findings of this NZDF study reinforce that there are dental caries concerns for young adults in New Zealand. Future similar surveys would be able to use this data to compare a wide range of oral health indicators. It will help the NZDF for its future health service planning, to evaluate changes over time, and to monitor progress to health targets and objectives.