Quantity and distribution of plaque in orthodontic patients treated with molar bands

Objective

The placement of orthodontic bands usually increases plaque accumulation due to numerous mechanical retention sites. The purpose of this investigation was to evaluate the amount and distribution pattern of biofilm in the oral (palatal and lingual) and interproximal regions surrounding orthodontic bands.

Materials and Methods

We evaluated the formation of biofilm on 32 orthodontic bands which had been placed intraorally for 6?C37?months. Two parameters were measured: the percentage of surface covered by biofilm (quantity) and the biofilm distribution pattern of accumulation. We measured these two parameters in four regions of interest: the mesial and distal interproximal regions, as well as the mesial and distal regions of the oral attachment.

Results

The quantity of biofilm formation was similar in all four regions of interest, ranging from 13.3% to 16.8%. In contrast to biofilm quantity, distribution patterns differed in the four regions. In the mesial and distal interproximal regions it appeared as extensive insular areas in 87.5% and 71.9%, respectively, whereas it appeared more often supragingival and linear in nature in regions adjacent to the oral attachment, i.e. in 65.6% and 68.8%, respectively.

Conclusion

Our results indicate that firstly, oral hygiene in the palatal and lingual regions of orthodontic bands seems as difficult as it is in the interproximal areas, thus requiring thorough hygiene in both areas. Secondly, orthodontic patients with a history of periodontal disease require special attention regarding the use of orthodontic bands.     

Cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis

OBJECTIVE: To investigate the cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis.
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study.     

Evaluation of treatment outcomes for Stenotrophomonas maltophilia bacteraemia

Objective

The goal of this study was to retrospectively collect data about treatment outcomes in patients diagnosed with Stenotrophomonas maltophilia bacteraemia over a period of 20 years and evaluate these data with respect to the efficacy of treatment options.

Methods

The setting was a 700-bed tertiary care hospital in a large urban area. Hospital databases and medical records provided information about episodes of S. maltophilia, patient characteristics and treatment outcomes. Patients with at least one positive blood culture for S. maltophilia were included in the study. Data were analysed with respect to clinical improvement and mortality ≤30 days after the onset of infection. We compared patient characteristics, laboratory values and treatments by using the Chi-square or Fisher’s exact tests and the Mann–Whitney test.

Results

We investigated 27 patients with S. maltophilia bacteraemia. The focus of infection was a central venous catheter in 18 (67 %) cases. The 30-day mortality rate was 11 %. All patients who were treated with an antibiotic that was effective in vitro against the pathogen recovered clinically and survived ≥30 days after the onset of infection. The most frequently used antibiotic was trimethoprim–sulfamethoxazole administered alone or in combination with a fluoroquinolone.

Conclusions

Despite the fact that S. maltophilia is resistant to multiple antibiotics, the prognosis for patients with S. maltophilia bacteraemia is good when they are treated with antibiotics that are effective against this pathogen in vitro.     

Minimal mechanical load and tissue culture conditions preserve native cell phenotype and morphology in tendon—a novel ex vivo mouse explant model

Appropriate mechanical load is essential for tendon homeostasis and optimal tissue function. Due to technical challenges in achieving physiological mechanical loads in experimental tendon model systems, the research community still lacks well‐characterized models of tissue homeostasis and physiological relevance. Toward this urgent goal, we present and characterize a novel ex vivo murine tail tendon explant model. Mouse tail tendon fascicles were extracted and cultured for 6 days in a load‐deprived environment or in a custom‐designed bioreactor applying low magnitude mechanical load (intermittent cycles to 1% strain, at 1 Hz) in serum‐free tissue culture. Cells remained viable, as did collagen structure and mechanical properties in all tested conditions. Cell morphology in mechanically loaded tendon explants approximated native tendon, whereas load‐deprived tendons lost their native cell morphology. These losses were reflected in altered gene expression, with mechanical loading tending to maintain tendon specific and matrix remodeling genes phenotypic of native tissue. We conclude from this study that ex vivo load deprivation of murine tendon in minimal culture medium results in a degenerative‐like phenotype. We further conclude that onset of tissue degeneration can be suppressed by low‐magnitude mechanical loading. Thus a minimal explant culture model featuring serum‐free medium with low mechanical loads seems to provide a useful foundation for further investigations. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1383–1390, 2018.

     

Real-time assessment of anteroposterior stability of spinal segments

Purpose

While anteroposterior instability of spinal segments is regarded as an important biomechanical aspect in the clinical evaluation of lumbar pathologies, the reliability of the available diagnostic tools is limited and an intraoperative method to quantify stability is lacking. The aim of this study was to develop and validate an instrument to measure the anteroposterior stability of a spinal segments in real-time.

Methods

Torsi of five fresh-frozen human cadavers were used for this study. After pedicle screw insertion, a specifically modified reposition tool composed with load and linear sensors was used to measure the segmental anteroposterior motion caused by 100 N anterior and posterior force during 5 loading cycles on either side of the instrumentation by two different operators. The spinal segments were then resected from the torsi and anteroposterior loading with ± 100 N was repeated in an advanced biomechanical spine testing setup as a reference measurement. The Inter-correlation coefficient (ICC) was used for validation of the “intraoperative” device.

Results

Inter-operator repeatability of the measurements showed an ICC of 0.93 (p < 0.0001) and the bilateral (left–right) comparison had an ICC of 0.73 (p < 0.0001). The ICC resulting from the comparison to the reference measurement was 0.82 (p < 0.0001) without offset correction, and 0.9 (p < 0.0001) with offset correction. The ICC converged at this value already after two of the five performed loading cycles.

Conclusion

An accurate and reliable measurement tool is developed and validated for real-time quantification of anteroposterior stability of spinal segments and serves as a basis for future intraoperative use.

     

Patient-based evaluations of primary care for cardiovascular diseases: a comparison between conventional and complementary medicine

Background Patients with chronic diseases, including cardiovascular conditions, increasingly rely on complementary and alternative medical (CAM) therapies. Objectives The Swiss Program for Complementary Medicine Evaluation offers a unique opportunity to analyse cardiovascular patients’ satisfaction with CAM and conventional medical (COM) therapies. The treatment choices of doctors certified in conventional as well as complementary therapies also could be studied. Methods A national observational evaluation on treatment satisfaction of patients consulting COM or CAM doctors. Out of this evaluation project, data related to patients with cardiovascular diseases were specifically analysed for patient satisfaction with treatment and outcome when treated by COM or CAM doctors. Results Of 199 included doctors (78 COM, 121 CAM) treating cardiovascular patients, COM doctors treated twice as many cardiovascular patients per doctor than CAM doctors. CAM doctors treated less than 1/3 of their cardiovascular patients solely by CAM, while they treated 42% exclusively by COM therapies. Patients seeing a CAM doctor had a significantly longer consultation and were more likely to be highly satisfied with overall treatment outcome and patient‐practitioner communication. Moreover, patients seeing a CAM doctor and being treated solely by a CAM therapy more often report ‘complete fulfilment of outcome expectation’ and ‘high overall satisfaction with treatment’, although their symptoms less often disappear totally than those of COM therapy‐treated patients. Conclusion CAM therapies are not the first treatment choice for cardiovascular diseases. However, even though CAM doctors preferentially apply COM therapies, cardiovascular patients treated by CAM doctors are more likely to be satisfied with the overall treatment outcome, possibly because of the longer and better patient–practitioner interaction.