The molecular and cellular mechanisms responsible for the etiology and pathogenesis of Alzheimer’s disease (AD) are not clearly defined, but progress is being made. Researchers know that inflammation within the brain is thought to be a major factor in the development of the disease. Studies suggest that peripheral infection/inflammation might affect the inflammatory state of the central nervous system.(1) Chronic periodontitis is a prevalent infection that is associated with gram-negative anaerobic bacteria and the elevation of serum inflammatory markers including C-reactive protein. Recently, chronic periodontitis has been associated with several systemic diseases including AD. In this article we review AD, its causes, prevalence, and treatments. In another, we will examine the link between AD and periodontal disease.Relevant data for researchers and professionals We can begin our learning by reviewing the current state of AD in the USA. A look at 2012 Alzheimer's Disease Facts and Figures provides statistical data on Alzheimer's disease in the United States, as well as data on other forms of dementia.(2) Specific information given includes: • Overall number of Americans with Alzheimer's, both nationally and by state; • Proportion of women and men with Alzheimer's and other dementias; • Prevalence of Alzheimer's; • Estimates of lifetime risk for developing Alzheimer's disease; • Costs of dementia for individuals, families, local and state government, and the nation's health system, from acute services to long-term care and hospice; • Number of family caregivers, hours of care provided, economic value of unpaid care nationally and for each state, and the impact of caregiving on caregivers; • Mortality due to Alzheimer's disease, both nationally and by state, and death rates by age.(2) AD is a type of dementia that causes problems with memory, thinking and behavior. Symptoms usually develop slowly and get worse over time, becoming severe enough to interfere with daily tasks.(3) AD is the most common form of dementia, an overall term for memory loss and other intellectual abilities serious enough to interfere with daily life. AD accounts for 50 to 80 percent of dementia cases.(3) It is not a normal part of aging, even though most of those afflicted are 65 years of age or older. It is a progressive disease, getting worse over time. There is no cure, but some medications can slow the progression of AD. The U.S. Food and Drug Administration (FDA) has approved two types of medications, cholinesterase inhibitors (Aricept, Exelon, Razadyne, Cognex) and memantine (Namenda), to treat the cognitive symptoms (memory loss, confusion, and problems with thinking and reasoning) of AD.(4) Memantine (Namenda) is approved by the FDA for treatment of moderate to severe AD’s, while the others are meant to treat earlier stages of AD. Memantine is prescribed to improve memory, attention, reason, language and the ability to perform simple tasks. It can be used alone or with other AD disease treatments. There is some evidence that individuals with moderate to severe AD who are taking a cholinesterase inhibitor might benefit by also taking memantine.(4) Donepezil (Aricept) is the only cholinesterase inhibitor approved to treat all stages of Alzheimer’s disease, including moderate to severe.