Fogorvosi szemle, 2006 (99. évfolyam, 1-6. szám)
2006-12-01 / 6. szám
248 FOGORVOSI SZEMLE ■ 99. évf. 6. sz. 2006. duction chain. Manufacturers supply zirconium oxide ceramic blanks of equal shape, so a mechanical process is also required for making the prosthesis. High strength zirconia materials cannot be processed using traditional laboratory methods (sintering, pressing, casting). One of the blessings of computerized dentistry is that it enabled the application of zirconium oxide. Frameworks can be milled either from partially sintered Y-TZP-based blanks, or fully sintered Y-TZP-based blanks. With a partially sintered milled framework, the size has to be increased to compensate for prospective shrinkage (20%) that occurs during final sintering. The milling process is faster and the wear and tear of hardware is less than the milling from a fully sintered blank. Hard processing of fully sintered zirconia (HIP) blanks require more time and labor. HIP stands for Hot Isostatic Pressing. High temperature and pressure is applied to condense the material and its gaining approximately 20% more in strength. Mechanical properties of zirconium oxide make it a reliable framework material for crown and bridge-work. The coping is then veneered in the dental laboratory with conventional build-up of specially developed dental porcelains. Introducing some of latest material and technological developments, authors present clinical cases of excellent biocompatibility zirconium oxide restorations, emphasizing medical-biological advantages of research in patient-care. References: 1. Cou P, Karlsson S: Precision of a CAD/CAM technique for the production of zirconium dioxide copings. IntJProsthodont 2004; 17: 577—580. 2. Luthardt RG, Holzhüter M, SandkuhlO, Herold V, Schnapp JD, Kuhlisch E, Walter M: Reliability and properties of ground Y-TZP-Zirconia Ceramics. J Dent Res 2002; 81 (7): 487—491. 3. Tinschert J, Natt G, Mautsch W, Spiekermann H, Anusavice KJ: Marginal fit of alumina-and zirconia-based fixed partial dentures produced by a CAD/CAM system. Oper Dent 2001 ; 26: 367-374. THE EFFECT OF PERIODONTAL TREATMENT FOR THE OUTCOME OF PREGNANCY GORZÓ, I.1, RADNAI, M.1, ELLER, J.2, NOVÁK, T.3, HEFFNER, N.1, PÁL, A.3 1 Department of Dentistry and Oral Surgery, University of Szeged, Hungary; department of Medical Informatics, University of Szeged, Hungary; department of Obstetrics and Gynecology, University of Szeged, Hungary Introduction: It was supposed in the last 15 years that chronic inflammatory periodontal disease may influence the date of childbirth and the weight of the newborn. One way to evidence the possible influence is to treat periodontal disease in a group of pregnant women and compare the results to untreated group, and see whether the longevity of pregnancy and the weight of the newborn increases after treatment. Materials and methods: Altogether 68 postpartum, non-smoking women, without any systemic disease were included into the study. Every mother had threat: ening premature labor. The examined mothers were divided into two groups - 41 of the pregnant women underwent preventive periodontal treatment (test group), the remainder 27 refused the periodontal treatment (control group). The following periodontal parameters were measured: PD, SBI, plaque index frequency of dental calculus mobility, recession. The results were compared with statistical methods. Results: According to the statistical analysis only the SPI values differed significantly between the test and control groups. The average weight of babies was 300 g higher in the treated group (test) than among those who refused the preventive periodontal measurements (control). The difference was highly signifi: cant. The longevity of pregnancy also was compared, but the difference did not prove significant although it j was longer in the treated (test) than in the non-treated (control) group. Conclusion: Our results support those opinions that preventive periodontal treatment may have a positive effect on the weight of the newborn baby, and may increase the longevity of pregnancy in case of threatening premature labor. DIAMETER CHANGES OF GINGIVAL VESSELS IN RESPONSE TO THE LOCAL ENGAGEMENT OF VEGF GYURKOVICS, M1, GYŐRFI, A1, IVÁNYI, I1, FAZEKAS, Á1, ROSIVALL, L2 department of Conservative Dentistry, Faculty of Dentistry, Semmelweis University, Budapest, Hungary; institute of Pathophysiology, Faculty of Medicine, Hungarian Academy of Sciences and Semmelweis University Nephrology Research Group, Budapest, Hungary Background: Vascular endothelial growth factor (VEGF) induces proliferation of endothelial cells, stimulates angiogenesis, and increases vascular permeability in many organs. Nevertheless we have only limited information about its role in gingival hemodynamics. Objectives: The aim of this study is to assess the acute circulatory effect of VEGF on the vital gingiva in rats. Materials and methods: Thirty anesthetized adult male Sprague-Dawley rats (356±37 g) were divided into two
