Osteoporosis and its associated low-trauma fractures may have dramatic outcomes in terms of morbidity, mortality, and health care costs. Therefore, effective preventive strategies dependent on early diagnosis and treatment are essential to mitigate the long-term effects of this silent disease.19
This study examined the oral health of adolescent and young adult females suffering from restrictive AN, and in particular the correlation of BMD between DXA and dental panoramic radiographs. General trends in the dental findings included almost impeccable hygiene as determined through dental and periodontal exams, as well as soft tissue findings that suggest overzealous brushing. Our results are important ones for dental providers and hygienists to consider, given that they represent front-line providers for adolescent girls and young women, especially with regard to routine health screening.
Primary outcomes for this study included the MCW as detected on dental panoramic radiographs and bone density as determined by the standard BMD screening tool, DXA. Our choice of outcomes was based in part upon studies in the literature that identified the anterior region of the mandible, considering regions obtained on dental radiographs, as a favorable site for BMD detection.20-22
One study found that the cortical index for diagnosing osteoporosis was noted to have both low sensitivity and specificity.23
Use of MCW measurements, in lieu of mandibular cortical porosity in the mental foramen region, was influenced by the recent release of findings from the OSTEODENT project.24
That project concluded that MCW had better efficacy than the mandibular cortical index in detecting osteoporosis and that there was no benefit in combining the two measurements. Although there has been little consensus as to an appropriate mandibular cortical thickness in the literature, a measurement of ≤3 mm has been suggested as an optimal threshold for further investigation to rule out osteoporosis.22
Taguchi et al.25
claimed that 60% of their patients who presented with an MCW of less than 3 mm were osteoporotic. Horner et al.20
found that reduction of the mandibular cortex below 3 mm in the mental foramen region was also associated with low bone mass at the spine, femoral neck, or forearm. Lastly, Karayianni et al.13
stated that only those subjects with the thinnest mandibular cortices (≤3 mm) warrant referral for further investigation, as they are more likely to have the disease. Interestingly, none of the current participants had a MCW ≤3mm, and the range of measurements from all three observers on all subjects was 3.4 mm to 7.4 mm. These findings may be attributable to the differences in study populations, in that we studied adolescent and young adult females and previous studies have included primarily postmenopausal women. Our results might have differed had we utilized digital radiography and accounted for errors in magnification by including a mechanism in our methodology to control for it. In addition, we also might have improved the accuracy of our findings by utilizing an increased number of examiners for our MCW measurements. However, a previous study found that one important barrier to using cortical width measurements in primary dental care is the significant observer variability in measurement that does not improve with individualized instruction.26
Despite our minimally rigorous methodology, our study showed that there was a weak positive correlation between BMD detected by DXA and MCW as measured on dental panoramic radiographs.
Krall et al.27
found a relationship between calcium and vitamin D supplement intake and the risk of tooth loss in the elderly. Patients with AN have been shown previously to have a better vitamin D status compared to healthy control subjects.28
The benefit is related in part to more consistent compliance with vitamin D supplementation and potentially, to increased levels of bioavailable vitamin D in underweight patients. The positive effects of vitamin D on the oral health of the current patients with AN, in addition to not having the deleterious effects of the binging/purging behavior, may have improved the overall oral health of this current clinic-based sample.
Willumsen and Graugaard29
found that women with eating disorders, overall, have a higher level of dental fear than do women within the general population. Furthermore, they reported that almost half of the women with high dental fear restricted contact with dentists. Their study also found that women with higher dental fear reported more significant dental pathology. These findings suggest that the patients who volunteered to participate in the current study could have potentially had less dental fear, and therefore fewer dental problems as they may have been more compliant with regular cleanings and dental assessments. As a result of the direct association between poorer dental health and higher dental fear, it is likely that we may have enrolled a sample enriched with better dental health, potentially introducing selection bias.
Limitations should be considered and acknowledged. First, the small number of study participants limited our statistical power. Secondly, there was a lack of correction for magnification errors during the radiographic imaging. In addition, not “prestaining” the subjects’ dentition with Red Cote tablets prior to checking for plaque may have led to a less stringent detection of plaque. Most studies have utilized plaque staining per World Health Organization guidelines.30
Finally, some data were obtained via self-report questionnaires which has its own inherent limitations, especially in adolescents.
There is the concern that a dentist may see an under-weight patient who has normal dental health and may over-look other symptomatology associated with AN, especially the classic dental signs of an eating disorder (e.g., increased incidence of caries, tooth enamel erosion). In the absence of these findings, dental professionals (both dentists and hygienists) could be falsely reassured regarding the bone health of AN patients due to a lack of awareness regarding objective findings associated with eating disorders, especially those of the restrictive subtype. This study highlights dental and periodontal findings in young patients with restrictive AN.