Early wound healing outcomes after regenerative periodontal surgery with enamel matrix derivatives or guided tissue regeneration: a systematic review

Background Proper wound healing after regenerative surgical procedures is an essential issue for clinical success. Guided tissue regeneration (GTR) and application of enamel matrix derivatives (EMD) are common means to regenerate periodontal tissues. Both methods bear considerable advantages due to their special characteristics, but also go along with certain disadvantages. Today, there is no consensus in the literature whether GTR or EMD show better results regarding early wound healing, which is considered a crucial stage in periodontal regeneration. Therefore, the aim of the present systematic review was to compare the early wound healing after regenerative periodontal surgery with either EMD or GTR treatment.MethodsAn electronic literature search in PubMed was performed to identify randomized clinical trials (RCTs) or clinical trials (CTs) comparing regenerative surgery employing EMD and/or GTR in patients with chronic periodontitis. Among the finally included studies, a qualitative and quantitative data extraction regarding early wound healing parameters was performed. Primary outcome parameters were early wound healing index (EWH), flap dehiscence, membrane exposure, suppuration and abscess formation during the first 6weeks. As secondary parameters, swelling and allergic reactions were assessed.ResultsSeven studies reporting 220 intrabony periodontal defects in 199 patients were analysed.Flap dehiscence was observed in two studies in 12% of the GTR treated sites and in 10.3% of those treated with EMD. Membrane exposure was evaluated in five studies and was registered in the 28.8% of the defects, while no dehiscence was reported on the EMD group. Swelling was reported only in one study in 8/16 GTR sites and 7/16 EMD sites. Due to considerable heterogeneity of parameters no meta-analysis was possible.ConclusionsDue to considerable heterogeneity of the published studies a clear beneficial effect of the EMD on the early wound healing outcomes after surgical treatment of periodontal intrabony defects cannot be confirmed.Standardized RCT studies are needed in order to allow for proper comparison of early wound healing after both types of surgical approaches

Comparative effectiveness of hand scaling by undergraduate dental students following a two-week pre-clinical training course

BACKGROUND The Bologna reform resulted in a drastic restructuring of pre-clinical training courses at the University of Zurich. The aim of this study was to assess student pre-clinical scaling/root planning skills after just 8.5 hours of manual training. MATERIAL AND METHODS Three consecutive classes of dental students (n = 41; n = 34; n = 48) were tasked with removing lacquer concrement from the maxillary left canine on a typodont using Gracey and universal (Deppeler M23A) curettes. At baseline (prior to instruction), a timed five-minute session of scaling/root planning was undertaken. The second scaling/root planning session was held immediately following training. Eight experienced dental hygienists and eight lay people served as positive and negative controls, using the same instruments and time limit, respectively. Instrumented teeth were collected, scanned and planimetrically analysed for the percentage of tooth surface cleaned. Statistical analyses were performed to assess the dental students' improvement after the training (Wilcoxon signed-rank test) and to compare it to that of laypeople and dental hygienists (Kruskal-Wallis rank sum test followed by Conover's post hoc test). RESULTS At baseline, the dental students' mean scaling scores of the cleaned surfaces were not significantly different than those of laypeople (29.8%, 31.0%, 42% vs 27.9%). However, after 8.5 hours of manual training, the students' ability to clean the maxillary tooth improved significantly and they achieved mean removal values of 61.7%, 79.5% and 76% compared to the 67.4% (P < .001) of the experienced dental hygienists (Tables Tables  and ). There were no statistically significant differences between the scores achieved by students after training and those achieved by experienced dental hygienists. CONCLUSION A shortened pre-clinical training time was sufficient for students to acquire the basic scaling/root planning skills needed in preparation for clinical training. Further research is needed to identify ways to help students consistently reach highest skill levels

Utilizing Machine Learning to Greatly Expand the Range and Accuracy of Bottom-Up Coarse-Grained Models Through Virtual Particles

Coarse-grained (CG) models parameterized using atomistic reference data, i.e., 'bottom up' CG models, have proven useful in the study of biomolecules and other soft matter. However, the construction of highly accurate, low resolution CG models of biomolecules remains challenging. We demonstrate in this work how virtual particles, CG sites with no atomistic correspondence, can be incorporated into CG models within the context of relative entropy minimization (REM) as latent variables. The methodology presented, variational derivative relative entropy minimization (VD-REM), enables optimization of virtual particle interactions through a gradient descent algorithm aided by machine learning. We apply this methodology to the challenging case of a solvent-free CG model of a 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipid bilayer and demonstrate that introduction of virtual particles captures solvent-mediated behavior and higher-order correlations which REM alone cannot capture in a more standard CG model based only on the mapping of collections of atoms to the CG sites.Comment: 35 pages, 9 figure

Effect of application of a PVP-iodine solution before and during subgingival ultrasonic instrumentation on post-treatment bacteremia: A randomized single-center placebo-controlled clinical trial

BACKGROUND: To assess the effect of concomitant subgingival rinsing with 10% PVP-iodine during subgingival instrumentation on the prevalence and magnitude of bacteremia of oral origin. MATERIALS AND METHODS: Subgingival instrumentation was performed with water or PVP-iodine rinse in patients with periodontitis. Prior to instrumentation, subjects gargled for 1 min with the allocated liquid. Pockets were then rinsed for 1 min and subgingivally instrumented with liquid-cooled (water/PVP-iodine) ultrasonic scalers (1 min). Two minutes later, a blood sample from the arm vein was drawn using a lysis centrifugation blood culture system for quantitative microbiological analysis. Non-parametric statistical tests were performed to assess differences in the prevalence and extent of bacteremia between groups. RESULTS: Of the 19 samples in each group, oral-borne bacteremia was detected in 10 of the control and 2 of the test samples. With an average of 3.0 [1;5] colony forming units, significantly less bacteria and bacteremia were found in the test group compared to the controls (12.2 [1;46]) (p=0.003). Anaerobic bacteria were not found in the test group. CONCLUSIONS: Bacteremia after subgingival instrumentation with concomitant PCP-iodine rinsing is reduced but not eliminated. Therefore, it might be recommended for patients at a high risk of endocarditis or infection of endoprostheses. However, preventive antibiotic treatment should not be omitted. This article is protected by copyright. All rights reserved

OpenMSCG: A Software Tool for Bottom-Up Coarse-Graining

The “bottom-up” approach to coarse-graining, for building accurate and efficient computational models to simulate large-scale and complex phenomena and processes, is an important approach in computational chemistry, biophysics, and materials science. As one example, the Multiscale Coarse-Graining (MS-CG) approach to developing CG models can be rigorously derived using statistical mechanics applied to fine-grained, i.e., all-atom simulation data for a given system. Under a number of circumstances, a systematic procedure, such as MS-CG modeling, is particularly valuable. Here, we present the development of the OpenMSCG software, a modularized open-source software that provides a collection of successful and widely applied bottom-up CG methods, including Boltzmann Inversion (BI), Force-Matching (FM), Ultra-Coarse-Graining (UCG), Relative Entropy Minimization (REM), Essential Dynamics Coarse-Graining (EDCG), and Heterogeneous Elastic Network Modeling (HeteroENM). OpenMSCG is a high-performance and comprehensive toolset that can be used to derive CG models from large-scale fine-grained simulation data in file formats from common molecular dynamics (MD) software packages, such as GROMACS, LAMMPS, and NAMD. OpenMSCG is modularized in the Python programming framework, which allows users to create and customize modeling “recipes” for reproducible results, thus greatly improving the reliability, reproducibility, and sharing of bottom-up CG models and their applications

Healthcare-associated infections (HAIs) during the coronavirus disease 2019 (COVID-19) pandemic: A time-series analysis

OBJECTIVE: To use interrupted time-series analyses to investigate the impact of the coronavirus disease 2019 (COVID-19) pandemic on healthcare-associated infections (HAIs). We hypothesized that the pandemic would be associated with higher rates of HAIs after adjustment for confounders. DESIGN: We conducted a cross-sectional study of HAIs in 3 hospitals in Missouri from January 1, 2017, through August 31, 2020, using interrupted time-series analysis with 2 counterfactual scenarios. SETTING: The study was conducted at 1 large quaternary-care referral hospital and 2 community hospitals. PARTICIPANTS: All adults ≥18 years of age hospitalized at a study hospital for ≥48 hours were included in the study. RESULTS: In total, 254,792 admissions for ≥48 hours occurred during the study period. The average age of these patients was 57.6 (±19.0) years, and 141,107 (55.6%) were female. At hospital 1, 78 CLABSIs, 33 CAUTIs, and 88 VAEs were documented during the pandemic period. Hospital 2 had 13 CLABSIs, 6 CAUTIs, and 17 VAEs. Hospital 3 recorded 11 CLABSIs, 8 CAUTIs, and 11 VAEs. Point estimates for hypothetical excess HAIs suggested an increase in all infection types across facilities, except for CLABSIs and CAUTIs at hospital 1 under the no pandemic scenario. CONCLUSIONS: The COVID-19 era was associated with increases in CLABSIs, CAUTIs, and VAEs at 3 hospitals in Missouri, with variations in significance by hospital and infection type. Continued vigilance in maintaining optimal infection prevention practices to minimize HAIs is warranted

Success of 6-mm Implants with Single-Tooth Restorations: A 3-year Randomized Controlled Clinical Trial

The aim of the study was to test whether implants of 6 mm in length perform equally well as 10-mm implants in terms of survival and marginal bone-level changes when supporting single crowns. Patients with a posterior single-tooth gap were randomly allocated to either the placement of a 6-mm (test) or 10-mm implant (control). The treatment protocol allowed for internal sinus lift but not for lateral bone augmentation. After a healing period of 10 wk, implants were loaded with screw-retained single crowns. Survival rates, number of pockets ≥5 mm, and bleeding-on-probing were assessed clinically. The change of marginal bone level and crown-to-implant ratios were analyzed by 2 examiners. Longitudinal intragroup analyses for marginal bone levels were performed applying the Wilcoxon signed rank test. Intergroup differences at baseline and at 3 y were compared using the Mann-Whitney U test. The effect of implant length and crown-to-implant ratio on changes of marginal bone level also was determined. Of 94 implants placed (47 test and 47 control), 78 implants (40 test and 38 control) were available for follow-up examination at 3 y of loading. One test implant was lost during the second year. Hence, implant survival was not significantly different between the 2 groups after 3 y (98% test; 100% control). We found no significant change in the crestal bone level from baseline to 3 y for test and control implants with -0.19 ± 0.62 mm and -0.33 ± 0.71 mm, respectively. The intergroup difference was not significant. Crown-to-implant ratios were not associated with a statistically significant difference in marginal bone loss. However, the number of sites with pockets ≥5 mm was significantly higher in the test group. Based on the 3-y assessment, the use of 6-mm implants can be considered a viable option when reconstructing posterior single tooth gaps (German Clinical Trials Registry: DRKS00006290)

Five-Year Survival of Short Single-Tooth Implants (6 mm): A Randomized Controlled Clinical Trial

The aim of the present study was to evaluate whether 6-mm dental implants in the posterior segments of either jaw perform equally well in terms of clinical and radiographic outcomes when compared with 10-mm implants after 5 y of loading. Patients with single-tooth gaps in the posterior area who were scheduled for implant therapy were randomly assigned to a group receiving either a 6- or 10-mm implant. After a healing period of 10 wk, implants were loaded with a screw-retained single crown and followed up at yearly intervals. Of 96 patients, 86 could be recalled after 5 y. The implant survival rates amounted to 91% (95% confidence interval: 0.836 to 0.998) for the 6-mm group and 100% for the 10-mm group ( P = 0.036). Median crown-to-implant (C/I) ratios were 1.75 (interquartile range [IQR], 1.50 to 1.90) for the 6-mm group and 1.04 (IQR, 0.95 to 1.15) for the 10-mm group, whereas the median marginal bone levels measured -0.29 mm (IQR, -0.92 to 0.23) for the 6-mm group and -0.15 mm (IQR: -0.93 - 0.41) for the 10-mm group after 5 y. The C/I ratio turned out to be statistically significant ( P < 0.001), whereas marginal bone levels showed no significant difference between the groups. The 6-mm implants exhibited significantly lower survival rates than the 10-mm implants over 5 y, whereas there was no difference between upper and lower jaws in terms of survival ( P = 0.58). Lost implants did not show any sign of marginal bone loss or peri-implant infection previous to loss of osseointegration. High C/I ratio and implant length had no significant effect on marginal bone level changes or technical and biological complications (German Clinical Trials Registry: DRKS00006290)

Altered muscular activation during prone hip extension in women with and without low back pain

<p>Abstract</p> <p>Background</p> <p>Altered movement pattern has been associated with the development of low back pain (LBP). The purpose of this study was to investigate the activity pattern of the ipsilateral erector spinae (IES) and contralateral erectorspinae (CES), gluteus maximus (GM) and hamstring (HAM) muscles during prone hip extension (PHE) test in women with and without LBP. A cross-sectional non-experimental design was used.</p> <p>Methods</p> <p>Convenience sample of 20 female participated in the study. Subjects were categorized into two groups: with LBP (n = 10) and without LBP (n = 10). The electromyography (EMG) signal amplitude of the tested muscles during PHE (normalized to maximum voluntary electrical activity (MVE)) was measured in the dominant lower extremity in all subjects.</p> <p>Results</p> <p>Statistical analysis revealed greater normalized EMG signal amplitude in women with LBP compared to non-LBP women. There was significant difference in EMG activity of the IES (P = 0.03) and CES (P = 0.03) between two groups. However, no significant difference was found in EMG signals of the GM (P = 0.11) and HAM (P = 0.14) among two groups.</p> <p>Conclusion</p> <p>The findings of this study demonstrated altered activation pattern of the lumbo-pelvic muscles during PHE in the women with chronic LBP. This information is important for investigators using PHE as either an evaluation tool or a rehabilitation exercise.</p