RPD can be classified as which level of prevention?
Primary Prevention
Primary prevention aims to avoid the development of a disease or disability in healthy individuals. Most population-based health promotion activities, such as encouraging less consumption of sugars to reduce caries risk, are primary preventive measures.  Other examples of primary prevention in medicine and dentistry include the use of fluoridated toothpaste, and vaccinations for infectious diseases like measles, mumps, rubella, and polio.
Secondary Prevention
The focus of secondary prevention is early disease detection, making it possible to prevent the worsening of the disease and the emergence of symptoms, or to minimize complications and limit disabilities before the disease becomes severe. Secondary prevention also includes the detection of disease in asymptomatic patients, with screening or diagnostic testing and preventing the spread of communicable diseases.  Examples in dentistry and medicine include screening for caries, periodontal screening and recording for periodontal disease, and screening for breast and cervical cancer.
Tertiary Prevention
The goal of tertiary prevention is to reduce the negative impact of an already-established disease by restoring function and reducing disease-related complications. 
Tertiary prevention also aims to improve the quality of life for people with disease.  In medicine and dentistry, tertiary prevention measures include the use of amalgam and composite fillings for dental caries, replacement of missing teeth with bridges, implants, or dentures, or insulin therapy for Type II diabetes.
Primary level
Secondary level
Tertiary level
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