EVIDENCE SYNTHESIS Relationship between periodontal disease and osteoporosis Emma Megson BSc BDent, Kostas Kapellas BScDent(Hons) and P. Mark Bartold BDS BScDent PhD DDSc FRACDS(Perio) Colgate Australian Clinical Dental Research Centre, Dental School, University of Adelaide, Adelaide, South Australia, Australia Abstract Background For many years an association between the low bone density of osteoporosis and increased risk of periodontal bone loss has been suspected. In this review the relationship between osteoporosis and periodontal disease is considered. Methods For this narrative review a very broad search strategy of the literature was developed using both PubMed and Scopus databases using the search words “perio” and “osteoporosis”. The reference lists from the selected papers were also scanned and this provided an additional source of papers for inclusion. The inclusion/exclusion criteria, were also quite liberal with only those papers dealing with bisphosphonates and osteonecrosis of the jaws, osteoporosis in edentulous individuals, as well as those not written in English being excluded. Results The data available suggest that reduced bone mineral density is a shared risk factor for periodontitis rather than a causal factor. However, more prospective studies are required to fully determine what, if any, relationship truly exists between periodontitis and reduced bone mineral density. Conclusions More prospective studies are required to determine what, if any, relationships exist between periodontal disease and reduced bone mineral density. Key words: bone density, osteoporosis, periodontal disease, tooth loss. Introduction Osteoporosis is a skeletal disorder characterised by a reduced apparent bone density or ‘too little bone in the bone’, which increases the risk of fracture. 1 The condition is generally diagnosed by Dual Energy X-ray Absorptiometry (DEXA), which allows patients to be classified as having osteoporosis, osteopenia or normal bone density based on site- and gender-specific cut-off values of the standard deviations (T-scores) from a reference group of young normal adults. These classification categories are: T-score below -2.5, osteoporosis; T-score between -1.5 and -2.5, osteopenia; and T-score > -1, normal. 2 Some authors prefer to base the normal range on the more conventional two standard devia- tions above and below the young normal means. 1 Data from the Third National Health and Nutrition Exami- nation Survey (NHANES III) 3 on adults aged 50 years or older in the USA estimate that 13–18% (4–6 million) of women have osteoporosis, as do 3–6% (1–2 million) of men. 4 However, these levels are projected to increase to 12 million cases of osteoporosis by 2010 and 14 million by 2020 in the USA alone, because of the ageing population. 5 Osteoporosis is a major public health problem because of the estimated 9 million associated fractures worldwide each year, including 1.6 million hip fractures. 6 Hip fractures in the elderly double the risk of death over the first 12 months of fracture, 7 with 20–30% of hip fracture patients dying within 12 months. 8–10 Those who survive suffer significant declines in functional status and quality of life, 10–13 and nearly 20% of hip fracture patients require long-term nursing home care, 11 an experi- ence regarded as worse than being dead by many of the elderly. 14 The main risk factor in women is the menopause, which is associated with an increase in bone resorption 15 associated with a fall in calcium absorption and rise in calcium excretion 16 that raises calcium requirement. In experimental animals, osteoporosis can be induced by calcium deficiency and/or ovariectomy because the mainte- nance of the serum calcium takes precedence over the integ- rity of the skeleton. Correspondence: Professor Mark Bartold, Colgate Australian Clinical Dental Research Centre, Dental School, University of Adelaide, Adelaide, SA 5005, Australia. Email: mark.bartold@adelaide.edu.au doi:10.1111/j.1744-1609.2010.00171.x Int J Evid Based Healthc 2010; 8: 129–139 © 2010 The Authors International Journal of Evidence-Based Healthcare © 2010 Blackwell Publishing Asia Pty Ltd