A 46-year-old woman complains of bleeding gums, suppuration, teeth mobility. She has been presenting with these signs for 10 years. On examination her upper and lower gums are hyperemic, swollen, bleed on touch. In the area of 42, 41, 31, and 32 periodontal pockets are up to 8 mm deep, contain purulent discharge; these teeth demonstrate mobility of the II-degree, other teeth present with mobility of the I degree. In the area of 42, 41, 31, and 32 X-ray shows interalveolar septa resorption by 1/2 of the root length and signs of osteoporosis. What is the most advisable method of surgical treatment in this case?