No 2 (2005)

The experimental study was made in vitro according to V.N. Tsarev, which made it possible to compare the count of the test-strain bacteria applied to a sample material and the number of adhered to bacteria in 1 sq cm. We used, for the experiment, anaerobic and elective anaerobic bacteria - Streptococcus sangis, Streptococcus mutans, Prevotella intermedia, Prevotellamelaninogenica, Fusobacterium nucleautum and Fusobacterium necroforum - as well as cultures of yeast-loike fungi Candida albicans. The of adhesion of microorganisms to new types of basic plastics was comparatively studied versus Forax aery I plastic. The in vitro research confirm that the new types of basics plastics used by us, unlike Ftorax, are to a less extent colonized by microbe flora. However, it is a fact of public knowledge that the in vivo colonization essentially differ from the in vitro study results.

Alloys of noble metals have been widely used in orthopedic dentistry. The have bee used for manufacturing both re movable and fixed dentures. The frameworks of removable clasp dental prostheses are made of cobalt-chrome alio or of alloys based on foreign-made gold. The range of available Russian gold alloys, i.e. alloy 900, allow 750 (GP750-90-80), super KM, super TZ does not meet the requirements of the international ISO 1562 standard applicabl to gold alloys used for making clasp dental prostheses. The department of hospital orthopedic dentistry and the de partment of materials, Moscow State Medical Dentistry Institute, jointly with the "Supermetal" Company designed > new Russian gold-based alloy for removable clasp dental prostheses "Super-LB" that is in line with the requiremeni of ISO 1562 applicable to type IV gold dental alloys and that is little different from foreign analogues. Finally, presented are the results of research of physical, mechanical and operational properties of the new Russian dental "Super-LB" alloy in comparison to foreign gold-based alloys designed for removable clasp dental prostheses and in comparison to cobalt-chrome alloys

Plasty of defects of jaws by different synthetic materials based on hydroxyapatite and collagen combined with blood enriched by platelets was performed; the plastic procedures included: 1. Gnathoplasty; 2. Reconstruction of the maxilla and lifting of the bottom of the maxillary sinus including installation of intraosteal dental implants in 6 persons; and 3. Plasty of osteal defects after cystectomy. 100% remodeling of materials implanted into mature bone was registered in 48persons, 70% remodeling - in 22persons and 50% remodeling - in 6persons. A comparative evaluation of osteointegration of synthetic bone performed in 124 patients of the control group showed a 100% genesis of mature bone in 22 persons, a 50% genesis - in 98 persons and formation of fibrous and osteoid tissue without mineralization - in 7 persons. The described plastic surgery is a significant factor of genesis of bone and of its remodeling

A method was elaborated for measuring the parameters of tooth resonance, whose frequency shows the condition of the tooth retention apparatus. The resonance frequency of the upper-jaw anterior teeth with periodontitis in the condition of relative physiological norm makes on the average 1200-1300 Hz. Probably, the resonance frequency of tooth fluctuations is apt to go down in pathological periodontium. Measurements of parameters of tooth resonance makes it possible to detect early changes in the tooth retention apparatus, which is important for the diagnosis of periodontal pathologies.

Fifty-three male patients, aged 22 to 52, underwent clinical examinations. 43 of them were pilots of supersonic aviation of the Armed Forces of the Russian Federation and 10 - virtually healthy persons with sonified mouth cavity without any pathological changes in the parodentium. The below clinical indices were used in dental examinations: hygiene, papillary-marginal-alveolar, bleeding and parodontal index. Apart from clinical dental examinations of pilots, the parameters of lipid peroxidation and of antioxidant protection were determined in mixed saliva, i.e. of products reacting with thiobarbituric acid, of ceruloplasmin, superoxide dismutase and catalase. As for persons with a pronounced inflammatory component in the parodentium there clinically registered reliably higher parameters of parodontal indices versus the group of pilots who had pathological changes, in the periodontium, of the dystrophic nature. The examination results of lipid peroxidation and of antioxidant protection showed heterogeneous changes of parameters in two groups of pilots. The detected changes can be conditioned by specific mechanisms of inflammatory and dystrophic signs in the parodontal tissues.

The study was held from June 2004 to September 2004 among 131 dentists. The occupational stress (OS) was diagnosed according to an OS stress scale in 57.3% of those involved in the study. The working conditions, environment, remuneration, career outlooks and self-appraisal were found to affect the OS degree.