TY JOUR TI TYPES OF CHANGES IN THE CONDITION OF THE MUCOUS MEMBRANE OF THE MAXILLARY SINUSES DURING PROLONGED CONTACT WITH TITANIUM STRUCTURES AND THEIR OUTCOMES KW titanium structures KW mucous membrane of the maxillary sinuses KW chronic sinusitis KW inflammation KW polyposis KW hyperplasia KW fibrosis KW respiratory complications JO Actual problems in dentistry AU Dovgerd, A.A. AU Sivolapov, K.A. PY 2025 IS 21 PB TIRAZH Publishing House