1. periodontal disease; gum disease
Wikipedia definition
2. PeriodontitisPeriodontitis  /ˌpɛrioʊdɒnˈtaɪtɪs/ or pyorrhea /ˌpaɪəˈriə/ is a set of inflammatory diseases affecting the periodontium, i.e. , the tissues that surround and support the teeth. Periodontitis involves progressive loss of the alveolar bone around the teeth, and if left untreated, can lead to the loosening and subsequent loss of teeth.
Read “Periodontitis” on English Wikipedia
Read “歯周病” on Japanese Wikipedia
Read “Periodontitis” on DBpedia


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