Periodontal disease and fluoride bone levels in two separate Iberian red deer populations

Abstract

The mandibles of 209 red deer (Cervus elaphus hispanicus) from 6 months to 15 years old, shot between 2001 and 2002 in the Sierra de Andújar Natural Park (n = 173) and National Park of Doñana (n = 36) in southern Spain, were studied in order to assess spatial variations in the occurrence of periodontal disease and bone fluoride levels in two separate populations. Similarities were found in periodontal disease prevalence between the study areas (20.8% in Sierra de Andújar Natural Park and 33.3% in National Park of Doñana), and enamel defects or abnormal abrasion (7-10%, respectively). There were also variations in fluoride levels according to the area and the occurrence of periodontal disease, irrespective of age. Fluoride content was significantly lower in deer in Sierra de Andújar (250.5 AE 158.9 mg F/kg ash) than in Doñana (752.4 AE 451.0 mg F/kg ash), and the higher levels of bone fluoride occurred in mandibles showing periodontal disease in both areas (358.6 AE 201.7 and 1224.9 AE 422.34 mg F/kg, respectively). The fluoride levels were lower than expected, typical of non-polluted areas, and there was no significant influence of the occurrence of enamel defects on the bone fluoride concentration. In these areas pathologically increased attrition, enamel discolouration or enamel surface lesions seem not to be caused by fluorosis, so that special care must also be taken in using macroscopic lesions instead of fluoride determination as an indicator for monitoring the magnitude of environmental contamination. Research into the global mineral content and possible deficiencies in certain minerals such as selenium, phosphorus and calcium interacting with fluoride is necessary in order to understand the high prevalence of periodontal disease in younger animals and the higher concentrations of fluoride in mandibles with periodontal disease.

Dental fluorosis and skeletal fluoride content as biomarkers of excess fluoride exposure in marsupials

“…The range of dental lesions observed in the marsupials, including enamel discoloration, enamel defects such as hypoplasia, pitting and flaking, and increased tooth wear, was similar to the characteristic dental lesions described for fluoride toxicosis in eutherian mammals (Kierdorf et al, 1993(Kierdorf et al, , 1996a(Kierdorf et al, ,b, 2000Shupe et al, 1984;Walton, 1988), as expected from the evolutionary convergence between marsupials and eutherians (Madsen et al, 2001). Although the observed dental abnormalities could in principle also result from congenital disease, malnutrition, mineral deficiencies, or disease such as parasitism during crown formation in juveniles (Azorit et al, 2012;Brook et al, 1997;Suckling, 1989), resources at this high-fluoride site have not been limited over the previous decade and a previous investigation that assessed gastrointestinal parasite levels, and levels of calcium, phosphorus and selenium in macropodid bones at this site, did not reveal any differences when compared to low-fluoride areas (Clarke et al, 2006). In addition, the histopathological changes documented in the dental enamel of marsupials from this known highfluoride site support the diagnosis of dental fluorosis (Kierdorf et al, unpublished observations).…”

“…We suspect that this swamp wallaby had dispersed from the high-fluoride area after eruption of the permanent dentition. Such aberrant cases highlight that special care must be taken in using macroscopic lesions in the absence of fluoride determination, as an indicator for monitoring the magnitude of environmental contamination by fluoride (Azorit et al, 2012).…”

Severe Dental Fluorosis in Juvenile Deer Linked to a Recent Volcanic Eruption in Patagonia

“…Whereas subadult red deer in unpolluted Spain averaged 79 ppm of dry bone fluoride, adults 8 to 15 yr old averaged 310 ppm (Azorit et al, 2012). Antlers constitute an unusual form of bone in that they are shed and regrown each year.…”