Experimental Study of the Biomechanics of Maxillary Implants under Conditions of Biomechanical Modeling.

We studied the stress-strain state of the bone tissue and maxillary full-arch fixed implantretained denture. Load was applied to the anterior (150 N) and posterior (250 N) parts of the denture supported by 6 or 4 implants, including zygomatic ones and placed by on-all-4 treatment technology. The obtained stress values in the bone tissue, implants, and denture show a large strength margin of structural materials. At the same time, the bone strength values were low, especially around the zygomatic and distal implants of all-on-4-implants-supported dentures when the posterior part of the denture was under load.

[The index assessment of periodontal status in the combined treatment of patients with generalized periodontitis]. / Indeksnaia otsenka sostoianiia parodonta v protsesse kompleksnogo lecheniia bol'nykh s generalizovannym parodontitom.

The authors compare the periodontal status in 94 patients with moderate periodontitis over the course of treatment making use of various splint designs and without splints. The status of the periodontium was assessed basing on the time course of indexes. Administration of various multiple-modality treatment schemes resulted in improvement of the periodontal clinical status in all the patients, though the efficacy of the therapeutic measures was different. The improvement in respect of all the examined parameters was the most manifest only in the group of patients treated with fixed splints with parapulpal fixation or with those pickling-based.

[A comparative analysis of the efficacy of combined treatment in generalized periodontitis of a moderate degree of severity using various splinting designs]. / Sravnitel'nyi analiz éffektivnosti kompleksnogo lecheniia generalizovannogo parodontita srednei stepeni tiazhesti s primeneniem razlichnykh shiniruiushchikh konstruktsii.

Immediate and late results of periodontitis treatment with the use of various types of joining in 74 patients are analyzed. Traditional casts were employed in 34 cases; in 40 patients fragmentary nonremovable casts with parapulpar fixation were used, as were adhesive one-piece, equatory, and intradental casts. The initial condition of the periodontium was similar in all the patients. Periodontal status was compared over the course of treatment with the use of different casts. Mathematical characteristics were used for analysis: periodontal and gingival indexes; osseous index and hygienic condition index, that were determined before, 30 days, and 12 months after treatment. Only two of the four studied indexes evidenced a reliable improvement of the condition after therapy and joining by traditional techniques, but the effect proved to be unstable, and 12 months after treatment both values significantly grew again. When traditional treatment modalities are used, alleviation of the inflammation and improvement of the hygienic condition of the oral cavity depend not so much on the type of joining but mostly on the initial status of the periodontium. A more manifest and stable reduction of the inflammation and improvement of the oral cavity hygienic status were observed in the patients treated with the use of present-day more physiologic cast designs. This evidence considerable advantages of these new designs vs. the traditional ones.