Dental Risk Assessment for Military Personnel

Military Medicine, Jun 2005 by Richardson, Peter S

In 2002, the U.K. Defence Dental Agency adopted a system of dental risk categories to replace the dental fitness categories detailed in NATO Standard Agreement 2466. Personnel were assessed as being at high, medium, or low risk of experiencing dental morbidity during the next year, and a target was set to have no less than 90% of personnel at low or medium risk. The Persian Gulf War in 2003 provided an opportunity to validate the risk assessment of U.K. troops deployed to Iraq (Operation Telic), when their morbidity experience was compared with the assessments of their risk. Data capture on risk assessment was considerably restricted but, for those for whom the comparison was possible, the predictive value of risk assessment appeared to be poor. However, 50% of all troops who were recorded as having experienced serious morbidity had been categorized as high risk. The system requires refinement of diagnostic criteria to maintain the sensitivity of the diagnosis of high risk while reducing the high false-positive assessment rate.

Introduction

Most NATO nations classify their military personnel into four dental fitness categories according to NATO Standard Agreement (STANAG) 2466, as follows: category 1, fully dentally fit; category 2, dental treatment is required but the condition is not expected to cause a problem within the next year; category 3, treatment is required and the condition is expected to cause a problem within the next year; category 4, dental examination is overdue. In theory, only personnel in dental fitness categories 1 and 2 should be allowed to deploy, but the precise definitions of each category and whether personnel in any categories are prevented from deploying varies from nation to nation. When nations follow STANAG 2466, placing an individual in category 2 is a risk assessment that the person's pathological condition is not so severe that he or she will experience morbidity within 12 months and placing an individual in category 3 is assessing him or her as being at high risk of morbidity over the next year.

Many nations have standard operating policies that mandate that certain types of conditions require classification in category 3. Others give more freedom of classification to clinicians to assess the level of risk. However, I am not aware of any nation that specifies the level of probability of an event occurring that differentiates low risk from high risk or category 2 from category 3.

Several studies investigated the predictive value of category 3 assessment for dental morbidity. Alien and Smith1 found that 85% of deployment sick calls were made by personnel in dental fitness category 3, and McClave and Brokaw2 reported that 50% of personnel identified as class 3 reported to sick call within 12 months. However, Amstutz3 reported that 27% of pathological conditions that subsequently caused morbidity had been charted but not recorded as class 3. Grover et al.4 found that only 34% of personnel identified as high risk reported dentally sick and those personnel formed only 19% of all emergencies. The Danes reported that they found it possible to make 100% of their troops fit for deployment at short notice and they would expect little need for treatment in the field.5 However, Mahoney and Coombs6 demonstrated that the annualized morbidity rates for well-prepared forces ranged between 150 and 200 cases per 1,000 personnel per year, and Alien and Smith1 reported that, even when there were essentially no class 3 personnel deployed, morbidity rates were still 160 cases per 1,000 personnel per year on a U.S. deployment to Sinai. Similarly, Chaffin et al.7 reported that U.S. Army personnel still had a dental emergency rate of 156 cases per 1,000 personnel per year despite no class 3 troops being deployed. Conversely, Jelaca-Bagic et al.8 reported that, in ill-prepared forces, the morbidity rate could rise fivefold to 755 cases per 1,000 personnel per year.

In recent years, the U.K. Armed Forces dental morbidity rates at home bases have tended to be higher than the operational rates experienced during Operation Telic (Table I). This may be because operational troops are better prepared or perhaps because they are less likely to request treatment while on operations: probably a combination of these reasons is closer to the truth.

Paradoxically, the peacetime dental morbidity data for U.K. forces show more dental emergency attendances in units with higher dental fitness rales. The optimal level of dental fitness for producing the least morbidity is in units where ≥80% of personnel have had all of their treatments completed. Morbidity rates are higher in units with fitness levels between 70 and 79% but fall in units with fitness levels between 60 and 69% and only rise again in units with fitness levels of less than 60%. These rather bizarre data are considered to be caused by a cultural disparity among the U.K. Services. The units with the highest fitness levels are universally Royal Air Force (RAF), and the lower fitness levels are universally found in Army units. RAF personnel are, on average, more highly educated and more dentally aware than Army personnel and have much higher expectations of their dental health than do Army personnel. Therefore, they tend to request emergency dental appointments for every minor problem, whereas some Army personnel are so stoical that morbidity must be severe before they can be bothered to request an appointment.