Maxillary sinus pathology treatment in implant-prosthetic rehabilitation: Summary of the Doctoral Thesis in Medical Sciences: 323.01 – Stomatology

Abstract

Actuality and importance of the studied problem Prosthetic rehabilitation has become a method of choice in treating patients without teeth (edentulous patients). Following tooth extraction, there is a progressive atrophy of the alveolar process, and often, specialists face a deficiency in bone support. In the lateral areas of the upper jaw, besides the atrophy of the alveolar process at the crown, there is also pneumatization of the maxillary sinus with resorption of the alveolar crest at the apical part. The most commonly used method for bone augmentation in the lateral areas of the upper jaw is the sinus lift (SL) procedure, which has proven its high efficiency and predictability over time. However, one of the primary conditions for performing SL is that the maxillary sinus (SM) must be intact. At the same time, there needs to be more data in the specialized literature regarding the criteria and boundaries for assessing the functional state of the maxillary sinus. It is well-established that the primary reason for postoperative complications of SL is the pathological state of the maxillary sinus before the operation [6, 7]. Sinus mucosal thickening is found in 23.7%-28.2% of patients, mucosal cysts in 8.9%-19.4%, and acute sinusitis in 3.6%- 6.5% of patients seeking implant-prosthetic rehabilitation [8, 9]. Beaumont (2005) reported that 40% of patients seeking SL have pathology of the maxillary sinus [5]. Analyzing the functional state of the maxillary sinus, the thickness of the Schneiderian mucosa, and the permeability of the natural ostium play a vital role in determining the indications and contraindications for SL. The issues and questions highlighted above, as well as many others encountered in our routine practice and by other specialists in the field, have motivated us to initiate this study. The purpose of the Study To evaluate the optimal treatment methods for maxillary sinus conditions in pre-implant preparation and to develop recommendations for the insertion of endosseous dental implants involving the operated maxillary sinus. Research Objectives Develop a methodology for clinical and paraclinical examination of patients indicated for the sinus lift procedure. Study the advantages and disadvantages of existing surgical techniques for pre-implant preparation in patients with maxillary sinus conditions. Evaluate the role of the osteomeatal complex in surgical treatment planning. Assess the role of anatomical deviations of the endonasal structures in the treatment of sinusitis and the planning of the sinus lift. Develop a method to clean the maxillary sinus in combination with a sinus lift in a single surgical stage through an intraoral approach. Scientific research methodology A controlled clinical study was conducted with randomized patient selection, comprising a total of 128 participants. The research subjects were divided into two groups. The study group included 65 patients undergoing sinus lifting with the presence of maxillary sinus pathology,

where functional endoscopic sinus surgery clearance was performed, followed by implant- prosthetic rehabilitation. The control group consisted of 63 patients who underwent surgical

treatment following modified Caldwell-Luc procedure, with subsequent implant-prosthetic rehabilitation.

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The study groups were compared based on the following outcome criteria:  Lund-Kennedy scale assessment;  OMU (osteomiatal unit) status assessment;  Sinus mucosa thickness assessment;  Persistence of postoperative pain (days);  Duration of the surgical intervention (minutes);  Healing duration (months);  Presence/absence of anterior maxillary sinus wall defect. Approval for the thesis topic was obtained during the Scientific Council meeting of the "Nicolae Testemițanu" State University of Medicine and Pharmacy (USMF), number 6, dated November 1, 2016. Positive feedback from the Research Ethics Committee for the study was obtained during the session on June 17, 2016. Scientific Novelty and Originality A step-by-step methodology for diagnostic rhinoscopy of sinus lifting candidates was developed. A step-by-step algorithm for CBCT examination of sinus lifting candidates was created. It was demonstrated for the first time that OMU blockage in maxillary sinusitis is usually secondary and occurs due to increased swelling of the sinus membrane. It was proven that anatomical deviations of endonasal structures are important factors but not determinants in the pathogenesis of sinusitis. The first endooral osteoplastic access to the maxillary sinus was developed. A novel method for treating fungal sinusitis in combination with sinus lifting through endooral access was proposed. Guidelines for the treatment of sinus lifting candidates with maxillary sinus conditions were developed. Implementation of Scientific Results The study results are applied in clinical practice and in the teaching process at the Department of Oro-Maxillofacial Surgery and Oral Implantology "A. Guțan" of USMF "Nicolae Testemițanu". Implementation details are provided in the Annex. Approval of Scientific Results: The results were presented in 27 active participations at national and international scientific forums, including various conferences and congresses. Thesis Publications: The main thesis materials were published in 2 articles with Impact Factor, 4 articles in category B journals, 3 articles in category C journals, 3 abstracts in international scientific conference proceedings, 1 single-author publication, and 2 innovation certificates. Thesis Volume and Structure: The thesis text consists of 136 pages of processed computer-based content, including a list of abbreviations, introduction, 4 chapters, general conclusions, practical recommendations, bibliography with 219 sources, and 2 annexes. The illustrative material includes 16 tables, 50 figures, and 2 formulas.