Periodontal disease, or gum disease, involves inflammation and infection of gum tissues, including conditions like gingivitis and periodontitis, and is a leading cause of adult tooth loss. It develops from untreated plaque and tartar buildup on teeth and gums. To prevent gum disease, brush teeth twice daily, floss once daily, and have regular dental exams and cleanings. Early signs like red, swollen gums, sensitive teeth, bleeding gums, bad breath, and discomfort while chewing indicate gingivitis, which can progress to periodontitis if untreated. Periodontitis can lead to gum recession, pockets forming around teeth, and potential tooth and bone loss without proper treatment.