A 16-year-old girl complains of burning. painful, and bleeding gums. Objectively, the gums of her upper and lower jaw are edematous, brightly hyperemic, and bleed when probed. Periodontal pockets are up to 4 mm deep and contain seropurulent exudate. The teeth have pathological mobility of the first degree. X-ray shows uneven resorption of the interalveolar septa up to 1/2 of their height with diffuser osteoporosis of the spongy (cancellous) bone tissue. Make the diagnosis.