[Morphological changes in the periodontium from the use of different designs of metal ceramic dentures]. / Morfologichsekie izmeneniia v parodonte pri primenenii razlichnykh konstruktsii metallokeramicheskikh protezov.

Morphological changes in the periodontium during the use of cermet crowns of different design were studied in experimental animals. The status of the periodontium was found to depend on the level of crown fixation with respect to gingival edge. Histological findings had show that position of a cermet crown at the level of the gingival edge does not involve appreciable changes in the periodontium, though preparation of abutment teeth with the formation of a step be considered as preferable. A subgingival position of cermet crowns leads to development of an inflammatory reaction in the periodontium, the severity of this reaction being related to a great measure to the method of the tooth preparation. If a step is formed during preparation of a tooth, the inflammatory changes are less pronounced than when there is no step formed. In the latter case the pathological changes were seen in the periodontium. The authors come to a conclusion that cermet crowns should be fixed at the level of the gingival edge. When making cermet crowns, abutment teeth should be prepared with the formation of a pericervical step.

[Structural changes in the periodontal tissues under measured exposure to intra- and extraoral orthodontic appliances in the unstable bite]. / Strukturnye izmeneniia tkanei parodonta pri dozirovannom vozdeistvii vnutri- i vnerotovoi ortodonticheskoi apparaturoi v smennom prikuse.

Study of the histological characteristics of the teeth, dental rudiments, and periodontal tissues of animals during distraction of the maxilla and distal dislocation of the mandible by "minor", "medium", and "strong" force showed that the type and degree of morphological changes are related to the strength of exposure and duration of orthodontist device application. The minor (1.2 H) and medium (2.5 H) force did not injure the studied structural elements of the periodical complex. Exposure of osseous tissues to a strong (5.0 H) force surpassing the compensatory potential of this tissue caused a complex of changes characterized by predominance of the processes of destruction of bone matter, specifically, by its resorption over its regeneration. These processes were the most evident during distal dislocation of the mandible. Appreciable foci of resorption were observed not only in the alveolar process bone, but in hard tissues (dentin and cement) of deciduous teeth as well. These results demonstrate the necessity of a careful approach to the choice of the intensity of force developed by various orthodontist devices.

[Reparative osteogenesis in the implantation of different modifications of a biocompatible polymer]. / Reparativnyi osteogenez pri implantatsii razlichnykh modifikatsii biosovmestimogo polimera.

Presents a histological picture of the time course of repair osteogenesis in replacement of bone tissue defects with implants made of 4 various copolymers of N-vinylpyrrolidone. Demonstrates excellent morphofunctional qualities of newly formed tissue substrate and its maturity in replacement of bone tissue defects with implants of N-vinylpyrrolidone with butylmethacrylate.

[An experimental study of the action of an intraosseous implant of hydroxylapatite ceramic granules on the processes of reparative bone formation (experimental morphological research)]. / Eksperimental'noe izuchenie vozdeistviia intraossal'noi podsadki granuliata keramiki gidroksilapatita na protsessy reparativnogo kosteobrazovaniia (éksperimental'no-morfologicheskoe issledovanie).

Presents a morphologic picture of the time course of repair osteogenesis after replacement of femoral bone defect in rats by hydroxyapatite ceramic granules. Excellent morphofunctional quality of newly formed bone regenerate in optimal terms is demonstrated.

[Morphological changes in the tissues of the prosthetic field with the use of different designs of metal ceramic bridge dentures]. / Morfologicheskie izmeneniia v tkaniakh proteznogo polia pri primenenii razlichnykh konstruktsii metallokeramicheskikh mostovidnykh protezov.

The results of experimental morphologic studies carried out in 23 dogs evidence that the status of the denture bed tissue beneath a whole-cast bridge cermet denture depends on the tightness of the denture adhesion to the gingival mucosa. If the denture poorly adheres to its bed, no marked changes in the structural components of the gingiva and the underlying bone support are detectable. If the denture adheres tightly to the gingiva, marked inflammatory dystrophic and destructive changes develop both in the gingiva and in the alveolar crest bone tissue. A complex of structural changes in the epithelium, connective tissue base of the gingival mucosa, and alveolar bone crest were traced. The results evidence that inflammatory dystrophic changes in the gingiva augment and result in the development of erosive ulcerative elements in the gingiva in case of a prolonged tight adhesion of the denture to the denture bed; sometimes decubital ulcers may develop in the gingiva. The resorptive processes take place in the underlying bone tissue, causing like smooth resorption of bone matter or to lacunar resorption. Diffuse rarification of bone tissue is also typical of such cases. Excessive pressure of the denture body in case of its tight adhering to denture bed seems to be detrimental not only for the epithelium, but for deeper structures of the gingival mucosa and the underlying bone structures as well.

[The periodontium in experimental bruxism]. / Sostoianie parodonta pri éksperimental'nom bruksizme.

Time course of morphologic changes in periodontal tissue was studied in 42 miniature pigs with experimental bruxism. An inflammation has developed in the marginal periodontium. At first the inflammatory infiltrate was situated under the epithelial fixation to the tooth involving destruction of the epithelial fixation and formation of pockets, inflammatory infiltrate, and granulation tissue, these destructive changes involving the lower sections of the periodontium. Signs of resorption were detectable in the dental alveolus osseous wall, cement, and dentin. The changes in the periodontal tissue described above appear to result from a complex of factors developing in experimental animals with simulated bruxism.

[A morphological evaluation of the tissue status of the oral mucosa after anesthesia applied with dicaine and pyromecaine solutions]. / Morfologicheskaia otsenka sostoianiia tkanei slizistoi obolochki rta posle applikatsionnoi anestezii rastvorami dikaina i piromekaina.

Effects of aqueous dicaine and pyromecaine solutions on mucosal tissue structures were studied in 40 syrian hamsters. The results evidence that when dicaine, an ether anesthetic, is applied, injuries prevail over reactive phenomena: a manifest cytotoxic effect of the drug can be seen at all phases of the follow-up, this effect being observed both in the mucosal epithelium and in the deeper layers of the mucosa. An amide anesthetic, pyromecaine, is not characterized by a cytotoxic action on mucosal epithelium cells, though in later periods of the experiment it also may induce side effects presenting as an acute inflammatory reaction developing in the subepithelial [correction of polyepithelial] connective tissue stroma and muscular layer.

[A new siloxane material for eliminating defects of the soft facial tissues by an injection method. I. The laboratory and experimental research]. / Novaia siloksanovaia kompozitsiia dlia ustraneniia defektov miagkikh tkanei litsa in''ektsionnym metodom. I. Laboratorno-éksperimental'noe issledovanie.

The authors present the results of laboratory and clinical analysis of vinyl siloxane polymer-based compositions, Pt catalyzer-hardened. Animal experiments have demonstrated high biologic inertness of the implantation material, inducing virtually no irritation of the adjacent tissues. These results confirm the possibility of clinical use of this new material.

[Morphofunctional parallels in the development of pulpitis]. / Morfofunktsional'nye paralleli v razvitii pul'pita.

In 16 mongrel dogs rheodontography was applied to study the functional state of inflamed dental pulp blood vessels. At the same time, pathological investigation of the pulp tissues was performed within 1 h to 40 days after the pulpitis modelling. Direct correlation of purulent-infiltrative pulp changes in acute and chronic inflammation with rheodentographic features was shown. The rheodentographic technique was shown effective for intravital diagnosis of the acute and chronic dental pulp inflammation.

[Age-related morphofunctional characteristics of the oral mucosa]. / Vozrastnye morfofunktsional'nye osobennosti slizistoi obolochki polosti rta.

Histological investigation of 250 fragments of grossly unaltered oral mucosa autopsied from patients aged 6 months to 87 years which had died of various diseases revealed phase relation of the evolution of oral mucosa reflecting its functional states. The morphofunctional characterization of ontogenesis of the mucosa and its derivatives yielded a close correlation of its morphofunctional features in different age groups with the type and course of its pathology.